Low-voltage high-reliability MEMS switch for millimeter wave 5G applications

NASA Astrophysics Data System (ADS)

Shekhar, Sudhanshu; Vinoy, K. J.; Ananthasuresh, G. K.

2018-07-01

Lack of reliability of radio-frequency microelectromechanical systems (RF MEMS) switches has inhibited their commercial success. Dielectric stiction/breakdown and mechanical shock due to high actuation voltage are common impediments in capacitive MEMS switches. In this work, we report low-actuation voltage RF MEMS switch and its reliability test. Experimental characterization of fabricated devices demonstrate that proposed MEMS switch topology needs very low voltage (4.8 V) for actuation. The mechanical resonant frequency, f 0, quality factor, Q, and switching time are measured to be 8.35 kHz, 1.2, and 33 microsecond, respectively. These MEMS switches have high reliability in terms of switching cycles. Measurements are performed using pulse waveform of magnitude of 6 V under hot-switching condition. Temperature measurement results confirm that the reported switch topology has good thermal stability. The robustness in terms of the measured pull-in voltage shows a variation of 0.08 V °C‑1. Lifetime measurement results after 10 million switching cycles demonstrate insignificant change in the RF performance without any failure. Experimental results show that low voltage improves the lifetime. Low insertion loss (less than 0.6 dB) and improved isolation (above 40 dB) in the frequency range up to 60 GHz have been reported. Measured RF characteristics in the frequency range from 10 MHz to 60 GHz support that these MEMS switches are favorable choice for mm-wave 5G applications.

Printed Antennas Made Reconfigurable by Use of MEMS Switches

NASA Technical Reports Server (NTRS)

Simons, Rainee N.

2005-01-01

A class of reconfigurable microwave antennas now undergoing development comprise fairly conventional printed-circuit feed elements and radiating patches integrated with novel switches containing actuators of the microelectromechanical systems (MEMS) type. In comparison with solid-state electronic control devices incorporated into some prior printed microwave antennas, the MEMS-based switches in these antennas impose lower insertion losses and consume less power. Because the radio-frequency responses of the MEMS switches are more nearly linear, they introduce less signal distortion. In addition, construction and operation are simplified because only a single DC bias line is needed to control each MEMS actuator.

Radio Frequency Microelectromechanical Systems [Book Chapter Manuscript

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nordquist, Christopher; Olsson, Roy H.

2014-12-15

Radio frequency microelectromechanical system (RF MEMS) devices are microscale devices that achieve superior performance relative to other technologies by taking advantage of the accuracy, precision, materials, and miniaturization available through microfabrication. To do this, these devices use their mechanical and electrical properties to perform a specific RF electrical function such as switching, transmission, or filtering. RF MEMS has been a popular area of research since the early 1990s, and within the last several years, the technology has matured sufficiently for commercialization and use in commercial market systems.

Simulation and test of the thermal behavior of pressure switch

NASA Astrophysics Data System (ADS)

Liu, Yifang; Chen, Daner; Zhang, Yao; Dai, Tingting

2018-04-01

Little, lightweight, low-power microelectromechanical system (MEMS) pressure switches offer a good development prospect for small, ultra-long, simple atmosphere environments. In order to realize MEMS pressure switch, it is necessary to solve one of the key technologies such as thermal robust optimization. The finite element simulation software is used to analyze the thermal behavior of the pressure switch and the deformation law of the pressure switch film under different temperature. The thermal stress releasing schemes are studied by changing the structure of fixed form and changing the thickness of the substrate, respectively. Finally, the design of the glass substrate thickness of 2.5 mm is used to ensure that the maximum equivalent stress is reduced to a quarter of the original value, only 154 MPa when the structure is in extreme temperature (80∘C). The test results show that after the pressure switch is thermally optimized, the upper and lower electrodes can be reliably contacted to accommodate different operating temperature environments.

Gamma-ray irradiation of ohmic MEMS switches

NASA Astrophysics Data System (ADS)

Maciel, John J.; Lampen, James L.; Taylor, Edward W.

2012-10-01

Radio Frequency (RF) Microelectromechanical System (MEMS) switches are becoming important building blocks for a variety of military and commercial applications including switch matrices, phase shifters, electronically scanned antennas, switched filters, Automatic Test Equipment, instrumentation, cell phones and smart antennas. Low power consumption, large ratio of off-impedance to on-impedance, extreme linearity, low mass, small volume and the ability to be integrated with other electronics makes MEMS switches an attractive alternative to other mechanical and solid-state switches for a variety of space applications. Radant MEMS, Inc. has developed an electrostatically actuated broadband ohmic microswitch that has applications from DC through the microwave region. Despite the extensive earth based testing, little is known about the performance and reliability of these devices in space environments. To help fill this void, we have irradiated our commercial-off-the-shelf SPST, DC to 40 GHz MEMS switches with gamma-rays as an initial step to assessing static impact on RF performance. Results of Co-60 gamma-ray irradiation of the MEMS switches at photon energies ≥ 1.0 MeV to a total dose of ~ 118 krad(Si) did not show a statistically significant post-irradiation change in measured broadband, RF insertion loss, insertion phase, return loss and isolation.

Design of RF MEMS switches without pull-in instability

NASA Astrophysics Data System (ADS)

Proctor, W. Cyrus; Richards, Gregory P.; Shen, Chongyi; Skorczewski, Tyler; Wang, Min; Zhang, Jingyan; Zhong, Peng; Massad, Jordan E.; Smith, Ralph

2010-04-01

Micro-electro-mechanical systems (MEMS) switches for radio-frequency (RF) signals have certain advantages over solid-state switches, such as lower insertion loss, higher isolation, and lower static power dissipation. Mechanical dynamics can be a determining factor for the reliability of RF MEMS. The RF MEMS ohmic switch discussed in this paper consists of a plate suspended over an actuation pad by four double-cantilever springs. Closing the switch with a simple step actuation voltage typically causes the plate to rebound from its electrical contacts. The rebound interrupts the signal continuity and degrades the performance, reliability and durability of the switch. The switching dynamics are complicated by a nonlinear, electrostatic pull-in instability that causes high accelerations. Slow actuation and tailored voltage control signals can mitigate switch bouncing and effects of the pull-in instability; however, slow switching speed and overly-complex input signals can significantly penalize overall system-level performance. Examination of a balanced and optimized alternative switching solution is sought. A step toward one solution is to consider a pull-in-free switch design. In this paper, determine how simple RC-circuit drive signals and particular structural properties influence the mechanical dynamics of an RF MEMS switch designed without a pull-in instability. The approach is to develop a validated modeling capability and subsequently study switch behavior for variable drive signals and switch design parameters. In support of project development, specifiable design parameters and constraints will be provided. Moreover, transient data of RF MEMS switches from laser Doppler velocimetry will be provided for model validation tasks. Analysis showed that a RF MEMS switch could feasibly be designed with a single pulse waveform and no pull-in instability and achieve comparable results to previous waveform designs. The switch design could reliably close in a timely manner, with small contact velocity, usually with little to no rebound even when considering manufacturing variability.

MEMS, Ka-Band Single-Pole Double-Throw (SPDT) Switch for Switched Line Phase Shifters

NASA Technical Reports Server (NTRS)

Scardelletti, Maximilian C.; Ponchak, George E.; Varaljay, Nicholas C.

2002-01-01

Ka-band MEMS doubly anchored cantilever beam capacitive shunt devices are used to demonstrate a MEMS SPDT switch fabricated on high resistivity silicon (HRS) utilizing finite ground coplanar waveguide (FGC) transmission lines. The SPDT switch has an insertion loss (IL), return loss (RL), and isolation of 0.3dB, 40dB, and 30 dB, respectively at Ka-band.

Numerical Simulation of Liquid Metal RF MEMS Switch Based on EWOD

NASA Astrophysics Data System (ADS)

Liu, Tingting; Gao, Yang; Yang, Tao; Guo, Huihui

2018-03-01

Conventional RF MEMS switches rely on metal-to-dielectric or metal-to-metal contacts. Some problems in the “solid-solid” contact, such as contact degradation, signal bounce and poor reliability, can be solved by using “liquid-solid” contact. The RF MEMS switch based on liquid metal is characterized by small contact resistance, no moving parts, high reliability and long life. Using electrowetting-on-dielectric (EWOD) way to control the movement of liquid metal in the RF MEMS switch, to achieve the “on” and “off” of the switch. In this paper, the electrical characteristics and RF characteristics of RF MEMS switches are simulated by fluid mechanics software FLUENT and electromagnetic simulation software HFSS. The effects of driving voltage, switching time, dielectric layer, hydrophobic layer material and thickness, switching channel height on the RF characteristics are studied. The results show that to increase the external voltage to the threshold voltage of 58V, the liquid metal began to move, and the switching time from “off” state to “on” state is 16ms. In the 0~20GHz frequency range, the switch insertion loss is less than 0.28dB, isolation is better than 23.32dB.

MEMS and FOG Technologies for Tactical and Navigation Grade Inertial Sensors—Recent Improvements and Comparison

PubMed Central

Deppe, Olaf; Dorner, Georg; König, Stefan; Martin, Tim; Voigt, Sven; Zimmermann, Steffen

2017-01-01

In the following paper, we present an industry perspective of inertial sensors for navigation purposes driven by applications and customer needs. Microelectromechanical system (MEMS) inertial sensors have revolutionized consumer, automotive, and industrial applications and they have started to fulfill the high end tactical grade performance requirements of hybrid navigation systems on a series production scale. The Fiber Optic Gyroscope (FOG) technology, on the other hand, is further pushed into the near navigation grade performance region and beyond. Each technology has its special pros and cons making it more or less suitable for specific applications. In our overview paper, we present latest improvements at NG LITEF in tactical and navigation grade MEMS accelerometers, MEMS gyroscopes, and Fiber Optic Gyroscopes, based on our long-term experience in the field. We demonstrate how accelerometer performance has improved by switching from wet etching to deep reactive ion etching (DRIE) technology. For MEMS gyroscopes, we show that better than 1°/h series production devices are within reach, and for FOGs we present how limitations in noise performance were overcome by signal processing. The paper also intends a comparison of the different technologies, emphasizing suitability for different navigation applications, thus providing guidance to system engineers. PMID:28287483

A novel multi-actuation CMOS RF MEMS switch

NASA Astrophysics Data System (ADS)

Lee, Chiung-I.; Ko, Chih-Hsiang; Huang, Tsun-Che

2008-12-01

This paper demonstrates a capacitive shunt type RF MEMS switch, which is actuated by electro-thermal actuator and electrostatic actuator at the same time, and than latching the switching status by electrostatic force only. Since thermal actuators need relative low voltage compare to electrostatic actuators, and electrostatic force needs almost no power to maintain the switching status, the benefits of the mechanism are very low actuation voltage and low power consumption. Moreover, the RF MEMS switch has considered issues for integrated circuit compatible in design phase. So the switch is fabricated by a standard 0.35um 2P4M CMOS process and uses wet etching and dry etching technologies for postprocess. This compatible ability is important because the RF characteristics are not only related to the device itself. If a packaged RF switch and a packaged IC wired together, the parasitic capacitance will cause the problem for optimization. The structure of the switch consists of a set of CPW transmission lines and a suspended membrane. The CPW lines and the membrane are in metal layers of CMOS process. Besides, the electro-thermal actuators are designed by polysilicon layer of the CMOS process. So the RF switch is only CMOS process layers needed for both electro-thermal and electrostatic actuations in switch. The thermal actuator is composed of a three-dimensional membrane and two heaters. The membrane is a stacked step structure including two metal layers in CMOS process, and heat is generated by poly silicon resistors near the anchors of membrane. Measured results show that the actuation voltage of the switch is under 7V for electro-thermal added electrostatic actuation.

RF MEMS Switches with SiC Microbridges for Improved Reliability

NASA Technical Reports Server (NTRS)

Scardelletti, Maximilian C.; Zorman, Christian A.; Oldham, Daniel R.

2008-01-01

Radio frequency (RF) microelectromechanical (MEMS) switches offer superior performance when compared to the traditional semiconductor devices such as PIN diodes or GaAs transistors. MEMS switches have a return loss (RL) better than -25 dB, negligible insertion loss (IL), isolation better than -30 dB, and near zero power consumption. However, RF MEMS switches have several drawbacks the most serious being long-term reliability. The ability for the switch to operate for millions or even billions of cycles is a major concern and must be addressed. MEMS switches are basically grouped in two categories, capacitive and metal-to-metal contact. The capacitive type switch consists of a movable metal bridge spanning a fixed electrode and separated by a narrow air gap and thin insulating material. The metal-to-metal contact type utilizes the same basic design but without the insulating material. After prolonged operation the metal bridges, in most of these switches, begin to sag and eventually fail to actuate. For the metal-to-metal type, the two metal layers may actually fuse together. Also if the switches are not packaged properly or protected from the environment moisture may build up and cause stiction between the top and bottom electrodes rendering them useless. Many MEMS switch designs have been developed and most illustrate fairly good RF characteristics. Nevertheless very few have demonstrated both great RF performance and ability to perform millions/billions of switching cycles. Of these, nearly all are of metal-to-metal type so as the frequency increases RF performance decreases.

A low-loss, single-pole, four-throw RF MEMS switch driven by a double stop comb drive

NASA Astrophysics Data System (ADS)

Kang, S.; Kim, H. C.; Chun, K.

2009-03-01

Our goal was to develop a single-pole four-throw (SP4T) radio frequency microelectromechanical system (RF MEMS) switch for band selection in a multi-band, multi-mode, front-end module of a wireless transceiver system. The SP4T RF MEMS switch was based on an arrangement of four single-pole single-throw (SPST) RF MEMS switches. The SP4T RF MEMS switch was driven by a double stop (DS) comb drive, with a lateral resistive contact, and composed of single crystalline silicon (SCS) on glass. A large contact force at a low-drive voltage was achieved by electrostatic actuation of the DS comb drive. Good RF characteristics were achieved by the large contact force and the lateral resistive Au-to-Au contact. Mechanical reliability was achieved by using SCS which has no residual stress as a structure material. The developed SP4T RF MEMS switch has a drive voltage of 15 V, an insertion loss below 0.31 dB at 6 GHz after more than one million cycles under a 10 mW signal, a return loss above 20 dB and an isolation value above 36 dB.

A High Isolation Series-Shunt RF MEMS Switch

PubMed Central

Yu, Yuan-Wei; Zhu, Jian; Jia, Shi-Xing; Shi, Yi

2009-01-01

This paper presents a wide band compact high isolation microelectromechanical systems (MEMS) switch implemented on a coplanar waveguide (CPW) with three ohmic switch cells, which is based on the series-shunt switch design. The ohmic switch shows a low intrinsic loss of 0.1 dB and an isolation of 24.8 dB at 6 GHz. The measured average pull-in voltage is 28 V and switching time is 47 μs. In order to shorten design period of the high isolation switch, a structure-based small-signal model for the 3-port ohmic MEMS switch is developed and parameters are extracted from the measured results. Then a high isolation switch has been developed where each 3-port ohmic MEMS switch is closely located. The agreement of the measured and modeled radio frequency (RF) performance demonstrates the validity of the electrical equivalent model. Measurements of the series-shunt switch indicate an outstanding isolation of more than 40 dB and a low insertion loss of 0.35 dB from DC to 12 GHz with total chip size of 1 mm × 1.2 mm. PMID:22408535

Investigation of improving MEMS-type VOA reliability

NASA Astrophysics Data System (ADS)

Hong, Seok K.; Lee, Yeong G.; Park, Moo Y.

2003-12-01

MEMS technologies have been applied to a lot of areas, such as optical communications, Gyroscopes and Bio-medical components and so on. In terms of the applications in the optical communication field, MEMS technologies are essential, especially, in multi dimensional optical switches and Variable Optical Attenuators(VOAs). This paper describes the process for the development of MEMS type VOAs with good optical performance and improved reliability. Generally, MEMS VOAs have been fabricated by silicon micro-machining process, precise fibre alignment and sophisticated packaging process. Because, it is composed of many structures with various materials, it is difficult to make devices reliable. We have developed MEMS type VOSs with many failure mode considerations (FMEA: Failure Mode Effect Analysis) in the initial design step, predicted critical failure factors and revised the design, and confirmed the reliability by preliminary test. These predicted failure factors were moisture, bonding strength of the wire, which wired between the MEMS chip and TO-CAN and instability of supplied signals. Statistical quality control tools (ANOVA, T-test and so on) were used to control these potential failure factors and produce optimum manufacturing conditions. To sum up, we have successfully developed reliable MEMS type VOAs with good optical performances by controlling potential failure factors and using statistical quality control tools. As a result, developed VOAs passed international reliability standards (Telcodia GR-1221-CORE).

Investigation of improving MEMS-type VOA reliability

NASA Astrophysics Data System (ADS)

Hong, Seok K.; Lee, Yeong G.; Park, Moo Y.

2004-01-01

MEMS technologies have been applied to a lot of areas, such as optical communications, Gyroscopes and Bio-medical components and so on. In terms of the applications in the optical communication field, MEMS technologies are essential, especially, in multi dimensional optical switches and Variable Optical Attenuators(VOAs). This paper describes the process for the development of MEMS type VOAs with good optical performance and improved reliability. Generally, MEMS VOAs have been fabricated by silicon micro-machining process, precise fibre alignment and sophisticated packaging process. Because, it is composed of many structures with various materials, it is difficult to make devices reliable. We have developed MEMS type VOSs with many failure mode considerations (FMEA: Failure Mode Effect Analysis) in the initial design step, predicted critical failure factors and revised the design, and confirmed the reliability by preliminary test. These predicted failure factors were moisture, bonding strength of the wire, which wired between the MEMS chip and TO-CAN and instability of supplied signals. Statistical quality control tools (ANOVA, T-test and so on) were used to control these potential failure factors and produce optimum manufacturing conditions. To sum up, we have successfully developed reliable MEMS type VOAs with good optical performances by controlling potential failure factors and using statistical quality control tools. As a result, developed VOAs passed international reliability standards (Telcodia GR-1221-CORE).

Nanoionics-Based Switches for Radio-Frequency Applications

NASA Technical Reports Server (NTRS)

Nessel, James; Lee, Richard

2010-01-01

Nanoionics-based devices have shown promise as alternatives to microelectromechanical systems (MEMS) and semiconductor diode devices for switching radio-frequency (RF) signals in diverse systems. Examples of systems that utilize RF switches include phase shifters for electronically steerable phased-array antennas, multiplexers, cellular telephones and other radio transceivers, and other portable electronic devices. Semiconductor diode switches can operate at low potentials (about 1 to 3 V) and high speeds (switching times of the order of nanoseconds) but are characterized by significant insertion loss, high DC power consumption, low isolation, and generation of third-order harmonics and intermodulation distortion (IMD). MEMS-based switches feature low insertion loss (of the order of 0.2 dB), low DC power consumption (picowatts), high isolation (>30 dB), and low IMD, but contain moving parts, are not highly reliable, and must be operated at high actuation potentials (20 to 60 V) generated and applied by use of complex circuitry. In addition, fabrication of MEMS is complex, involving many processing steps. Nanoionics-based switches offer the superior RF performance and low power consumption of MEMS switches, without need for the high potentials and complex circuitry necessary for operation of MEMS switches. At the same time, nanoionics-based switches offer the high switching speed of semiconductor devices. Also, like semiconductor devices, nanoionics-based switches can be fabricated relatively inexpensively by use of conventional integrated-circuit fabrication techniques. More over, nanoionics-based switches have simple planar structures that can easily be integrated into RF power-distribution circuits.

Applications of Non-linearities in RF MEMS Switches and Resonators

NASA Astrophysics Data System (ADS)

Vummidi Murali, Krishna Prasad

The 21st century is emerging into an era of wireless ubiquity. To support this trend, the RF (Radio Frequency) front end must be capable of processing a range of wireless signals (cellular phone, data connectivity, broadcast TV, GPS positioning, etc.) spanning a total bandwidth of nearly 6 GHz. This warrants the need for multi-band/multi-mode radio architectures. For such architectures to satisfy the constraints on size, battery life, functionality and cost, the radio front-end must be made reconfigurable. RF-MEMS (RF Micro-Electro-Mechanical Systems) are seen as an enabling technology for such reconfigurable radios. RF-MEMS mainly include micromechanical switches (used in phase shifters, switched capacitor banks, impedance tuners etc.) and micromechanical resonators (used in tunable filters, oscillators, reference clocks etc.). MEMS technology also has the potential to be directly integrated into CMOS (Complementary metal-oxide semiconductor) ICs (Integrated Circuits) leading to further potential reductions of cost and size. However, RF-MEMS face challenges that must be addressed before they can gain widespread commercial acceptance. Relatively low switching speed, power handling, and high-voltage drive are some of the key issues in MEMS switches. Phase noise influenced by non-linearities, need for temperature compensation (especially Si based resonators), large start-up times, and aging are the key issues in Si MEMS Resonators. In this work potential solutions are proposed to address some of these key issues, specifically the reduction of high voltage drives in switches and the reduction of phase noise in MEMS resonators for timing applications. MEMS devices that are electrostatically actuated exhibit significant non-linearities. The origins of the non-linearities are both electrical (electrostatic actuation) and mechanical (dimensions and material properties). The influence of spring non-linearities (cubic and quadratic) on the performance of switches and resonators are studied. Gold electroplated fixed-fixed beams were fabricated to test the phenomenon of dynamic (or resonant) pull-in in shunt switches. The dynamic pull-in phenomenon was also tested on commercially fabricated lateral switches. It is shown that the resonant pull-in technique reduces the overall voltage required to actuate the switch. There is an additional reduction of total actuation voltage possible via applying an AC actuation signal at the correct non-linear resonant frequency. The demonstrated best case savings from operating at the non-linear resonance is 50% (for the lateral switch) and 60% (for the vertical switch) as compared to 25% and 40% respectively using a fixed frequency approach. However, the timing response for resonant pull-in has been experimentally shown to be slower than the static actuation. To reduce the switching time, a shifted-frequency method is proposed where the excitation frequency is shifted up or down by a discrete amount deltaO after a brief hold time. It was theoretically shown that the shifted-frequency method enables a minimum realizable switching time comparable to the static switching time for a given set of actuation frequencies. The influence of VDC on the effective non-linearities of a fixed-fixed beam is also studied. Based on the dimensions of the resonator and the type of resonance there is a certain VDC,Lin where the response is near linear (S ≈ 0). In the near-linear domain, the dynamic pull-in is the only upper bound to the amplitude of vibrations, and hence the amplitude of output current, thereby maximizing the power handling capacity of the resonator. Apart from maximizing the output current, it is essential to reduce the amplitude and phase variations of the displacement response which are due to noise mixing into frequency of interest, and are eventually manifested as output phase noise due to capacitive current nonlinearity. Two major aliasing schemes were analyzed and it was shown that the capacitive force non-linearity is the major source of mixing that causes the up-conversion of 1/f frequency into signal sidebands. The resonator's periodic response (displacement) is defined by a set of two first-order nonlinear ordinary differential equations that describe the modulation of amplitude and phase of the response. Frequency response curves of amplitude and frequency are determined from these modulation equations. The zero slope point on the amplitude resonance curve is the peak of the resonance curve where the phase (gammadc) of the response is +/-pi/2. For a strongly non-linear system, the resonance curves are skewed based on the amount of total non-linearity S. For systems that are strongly non-linear, the best region to operate the resonator is the fixed point that correspond to infinite slope (gammadc = +/-2pi/3) in the frequency response of the system. The best case phase noise response was analytically developed for such a fixed point. Theoretically at this fixed point, phase noise will have contributions only from 1/ fnoise and not from 1/f2 and 1/ f3. The resonators phase can be set by controlling the rest of the phase in the loop such that the total phase around the loop is zero or 2pi. In addition, this work has also developed an analytical model for a lateral MEMS switch fabricated in a commercial foundry that has the potential to be processed as MEMS on CMOS. This model accounts for trapezoidal cross sections of the electrodes and springs and also models electrostatic fringing as a function of the moving gap. The analytical model matches closely with the Finite Element (FEA) model.

Finite Ground Coplanar Waveguide Shunt MEMS Switches for Switched Line Phase Shifters

NASA Technical Reports Server (NTRS)

Ponchak, George E.; Simons, Rainee N.; Scardelletti, Maximillian; Varaljay, Nicholas C.

2000-01-01

Switches with low insertion loss and high isolation are required for switched line phase shifters and the transmit/receive switch at the front end of communication systems. A Finite Ground Coplanar (FGC) waveguide capacitive, shunt MEMS switch has been implemented on high resistivity Si. The switch has demonstrated an insertion loss of less than 0.3 dB and a return loss greater than 15 dB from 10 to 20, GHz. The switch design, fabrication, and characteristics are presented.

A 0.2 V Micro-Electromechanical Switch Enabled by a Phase Transition.

PubMed

Dong, Kaichen; Choe, Hwan Sung; Wang, Xi; Liu, Huili; Saha, Bivas; Ko, Changhyun; Deng, Yang; Tom, Kyle B; Lou, Shuai; Wang, Letian; Grigoropoulos, Costas P; You, Zheng; Yao, Jie; Wu, Junqiao

2018-04-01

Micro-electromechanical (MEM) switches, with advantages such as quasi-zero leakage current, emerge as attractive candidates for overcoming the physical limits of complementary metal-oxide semiconductor (CMOS) devices. To practically integrate MEM switches into CMOS circuits, two major challenges must be addressed: sub 1 V operating voltage to match the voltage levels in current circuit systems and being able to deliver at least millions of operating cycles. However, existing sub 1 V mechanical switches are mostly subject to significant body bias and/or limited lifetimes, thus failing to meet both limitations simultaneously. Here 0.2 V MEM switching devices with ≳10 6 safe operating cycles in ambient air are reported, which achieve the lowest operating voltage in mechanical switches without body bias reported to date. The ultralow operating voltage is mainly enabled by the abrupt phase transition of nanolayered vanadium dioxide (VO 2 ) slightly above room temperature. The phase-transition MEM switches open possibilities for sub 1 V hybrid integrated devices/circuits/systems, as well as ultralow power consumption sensors for Internet of Things applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ultrananocrystalline diamond films with optimized dielectric properties for advanced RF MEMS capacitive switches

DOEpatents

Sumant, Anirudha V.; Auciello, Orlando H.; Mancini, Derrick C.

2013-01-15

An efficient deposition process is provided for fabricating reliable RF MEMS capacitive switches with multilayer ultrananocrystalline (UNCD) films for more rapid recovery, charging and discharging that is effective for more than a billion cycles of operation. Significantly, the deposition process is compatible for integration with CMOS electronics and thereby can provide monolithically integrated RF MEMS capacitive switches for use with CMOS electronic devices, such as for insertion into phase array antennas for radars and other RF communication systems.

Vibration nullification of MEMS device using input shaping

NASA Astrophysics Data System (ADS)

Jordan, Scott; Lawrence, Eric M.

2003-07-01

The active silicon microstructures known as Micro-Electromechanical Systems (MEMS) are improving many existing technologies through simplification and cost reduction. Many industries have already capitalized on MEMS technology such as those in fields as diverse as telecommunications, computing, projection displays, automotive safety, defense and biotechnology. As they grow in sophistication and complexity, the familiar pressures to further reduce costs and increase performance grow for those who design and manufacture MEMS devices and the engineers who specify them for their end applications. One example is MEMS optical switches that have evolved from simple, bistable on/off elements to microscopic, freelypositionable beam steering optics. These can be actuated to discrete angular positions or to continuously-variable angular states through applied command signals. Unfortunately, elaborate closed-loop actuation schemes are often necessitated in order to stabilize the actuation. Furthermore, preventing one actuated micro-element from vibrationally cross-coupling with its neighbors is another reason costly closed-loop approaches are thought to be necessary. The Laser Doppler Vibrometer (LDV) is a valuable tool for MEMS characterization that provides non-contact, real-time measurements of velocity and/or displacement response. The LDV is a proven technology for production metrology to determine dynamical behaviors of MEMS elements, which can be a sensitive indicator of manufacturing variables such as film thickness, etch depth, feature tolerances, handling damage and particulate contamination. They are also important for characterizing the actuation dynamics of MEMS elements for implementation of a patented controls technique called Input Shaping«, which we show here can virtually eliminate the vibratory resonant response of MEMS elements even when subjected to the most severe actuation profiles. In this paper, we will demonstrate the use of the LDV to determine how the application of this compact, efficient algorithm can improve the performance of both open- and closed-loop MEMS devices, eliminating the need for costly closed-loop approaches. This can greatly reduce the complexity, cost and yield of MEMS design and manufacture.

Uncertainty quantification in capacitive RF MEMS switches

NASA Astrophysics Data System (ADS)

Pax, Benjamin J.

Development of radio frequency micro electrical-mechanical systems (RF MEMS) has led to novel approaches to implement electrical circuitry. The introduction of capacitive MEMS switches, in particular, has shown promise in low-loss, low-power devices. However, the promise of MEMS switches has not yet been completely realized. RF-MEMS switches are known to fail after only a few months of operation, and nominally similar designs show wide variability in lifetime. Modeling switch operation using nominal or as-designed parameters cannot predict the statistical spread in the number of cycles to failure, and probabilistic methods are necessary. A Bayesian framework for calibration, validation and prediction offers an integrated approach to quantifying the uncertainty in predictions of MEMS switch performance. The objective of this thesis is to use the Bayesian framework to predict the creep-related deflection of the PRISM RF-MEMS switch over several thousand hours of operation. The PRISM switch used in this thesis is the focus of research at Purdue's PRISM center, and is a capacitive contacting RF-MEMS switch. It employs a fixed-fixed nickel membrane which is electrostatically actuated by applying voltage between the membrane and a pull-down electrode. Creep plays a central role in the reliability of this switch. The focus of this thesis is on the creep model, which is calibrated against experimental data measured for a frog-leg varactor fabricated and characterized at Purdue University. Creep plasticity is modeled using plate element theory with electrostatic forces being generated using either parallel plate approximations where appropriate, or solving for the full 3D potential field. For the latter, structure-electrostatics interaction is determined through immersed boundary method. A probabilistic framework using generalized polynomial chaos (gPC) is used to create surrogate models to mitigate the costly full physics simulations, and Bayesian calibration and forward propagation of uncertainty are performed using this surrogate model. The first step in the analysis is Bayesian calibration of the creep related parameters. A computational model of the frog-leg varactor is created, and the computed creep deflection of the device over 800 hours is used to generate a surrogate model using a polynomial chaos expansion in Hermite polynomials. Parameters related to the creep phenomenon are calibrated using Bayesian calibration with experimental deflection data from the frog-leg device. The calibrated input distributions are subsequently propagated through a surrogate gPC model for the PRISM MEMS switch to produce probability density functions of the maximum membrane deflection of the membrane over several thousand hours. The assumptions related to the Bayesian calibration and forward propagation are analyzed to determine the sensitivity to these assumptions of the calibrated input distributions and propagated output distributions of the PRISM device. The work is an early step in understanding the role of geometric variability, model uncertainty, numerical errors and experimental uncertainties in the long-term performance of RF-MEMS.

Integrated MEMS-tunable VCSELs for reconfigurable optical interconnects

NASA Astrophysics Data System (ADS)

Kögel, Benjamin; Debernardi, Pierluigi; Westbergh, Petter; Gustavsson, Johan S.; Haglund, Åsa; Haglund, Erik; Bengtsson, Jörgen; Larsson, Anders

2012-03-01

A simple and low-cost technology for tunable vertical-cavity surface-emitting lasers (VCSELs) with curved movable micromirror is presented. The micro-electro-mechanical system (MEMS) is integrated with the active optical component (so-called half-VCSEL) by means of surface-micromachining using a reflown photoresist droplet as sacrificial layer. The technology is demonstrated for electrically pumped, short-wavelength (850 nm) tunable VCSELs. Fabricated devices with 10 μm oxide aperture are singlemode with sidemode suppression >35 dB, tunable over 24 nm with output power up to 0.5mW, and have a beam divergence angle <6 °. An improved high-speed design with reduced parasitic capacitance enables direct modulation with 3dB-bandwidths up to 6GHz and error-free data transmission at 5Gbit/s. The modulation response of the MEMS under electrothermal actuation has a bandwidth of 400 Hz corresponding to switching times of about 10ms. The thermal crosstalk between MEMS and half-VCSEL is negligible and not degrading the device performance. With these characteristics the integrated MEMS-tunable VCSELs are basically suitable for use in reconfigurable optical interconnects and ready for test in a prototype system. Schemes for improving output power, tuning speed, and modulation bandwidth are briefly discussed.

Special Technology Area Review on Micro-Opto-Electro-Mechanical-Systems (MOEMS)

DTIC Science & Technology

1997-12-01

Optical Interference in Night Vision Systems "* DMD Assisted Intelligent Manufacturing of ................................................... SRI...CONCEPT ......................................... p. 8 FIGURE 3(a): DMD LIGHT SWITCHES...p. 9 FIGURE 3(b): SEM PHOTOMICROGRAPHS OF DMD CHIPS ........................................ p. 9 FIGURE 4: MULTI-USER MEMS PROJECTS (MUMPS

Preface

NASA Astrophysics Data System (ADS)

Dascalu, Dan; Muller, Alexandru

2003-07-01

It is a great pleasure for us to introduce this special issue featuring selected papers from the 13th European Micromechanics Workshop, MME'02, organized by the National Institute for R&D in Microtechnologies (IMT Bucharest). The conference was held in the beautiful mountain resort Sinaia, a former Romanian royal residence, 120 km north of Bucharest. In 1989 the first MME workshop was held in Twente, since then it has traveled from one Western European country to another. MME'02 is the first workshop to have been held in Eastern Europe. MEMS consolidated as an exciting field for research and development over the past decade and the MEMS industry is now a substantial presence. Commercial applications of MEMS technology now include pressure, chemical, acceleration, rotation rate sensors, microphones, microdevices in microfluidic systems for bio-engineering, RF switches and fiber optic networks (optical switches), etc. Microtechnology is one of the major growth markets of the 21st century. Microsystems are now key products in information and communication technology, automotive engineering and are also increasing in the fields of chemistry and life sciences. The 6th Framework Programme, already underway, promotes long-term initiatives in this area of research. After reviewing 72 high-quality abstracts submitted for the conference, the programme organizers selected 68 for presentation during the one and half days of the workshop. There were 62 papers from Europe and six papers from outside Europe (USA, Canada and Singapore). The papers covered materials, processing, modeling and applications of micromachining and micromachined devices. Following the tradition of the MME workshops, non-invited papers were discussed at poster sessions after a short oral presentation. This formula was again highly appreciated and stimulated much discussion between scientists. Five invited papers were also presented orally. These invited talks reviewed the latest technological developments in MEMS topics. This year special attention was devoted to the emerging RF MEMS technology. In addition, a presentation of `Microsystems in FP6' was held as a special invited talk at the end of the conference. The selection of papers for inclusion in this issue was difficult, due to the high quality of the papers of the workshop. The final content is a result of the collaboration of the programme committee and Institute of Physics Publishing staff. We wish to thank our colleagues from the MME'02 programme committee: A G R Evans (Southampton University), M Hill (Cork Institute of Technology) and R Wolffenbuttel (Delft University of Technology). We are grateful to all participants for making the workshop a very stimulating meeting place for the MEMS community in Europe.

High-speed wavelength switching of tunable MEMS vertical cavity surface emitting laser by ringing suppression

NASA Astrophysics Data System (ADS)

Inoue, Shunya; Nishimura, Shun; Nakahama, Masanori; Matsutani, Akihiro; Sakaguchi, Takahiro; Koyama, Fumio

2018-04-01

For use in wavelength division multiplexing (WDM) with high-speed wavelength routing functions, the fast wavelength switching of tunable lasers is a key function. A tunable MEMS vertical cavity surface emitting laser (VCSEL) is a good candidate as a light source for this purpose. The cantilever in MEMS VCSELs has a high mechanical resonance frequency thanks to its small size, but the switching time is limited by the ringing of the cantilever structure. In this paper, we analyzed the mechanical behavior of a cantilever MEMS mirror and demonstrated ringing-free operation with an engineered voltage signal. The applied voltage waveform was optimized in a two-step format and we experimentally obtained ringing free wavelength switching. We measured the transient response of the wavelength by inserting a tunable filter, exhibiting the settling time of less than 2.5 µs, which corresponds to a half period of the cantilever resonance frequency.

Finite element based contact analysis of radio frequency MEMs switch membrane surfaces

NASA Astrophysics Data System (ADS)

Liu, Jin-Ya; Chalivendra, Vijaya; Huang, Wenzhen

2017-10-01

Finite element simulations were performed to determine the contact behavior of radio frequency (RF) micro-electro-mechanical (MEM) switch contact surfaces under monotonic and cyclic loading conditions. Atomic force microscopy (AFM) was used to capture the topography of RF-MEM switch membranes and later they were analyzed for multi-scale regular as well as fractal structures. Frictionless, non-adhesive contact 3D finite element analysis was carried out at different length scales to investigate the contact behavior of the regular-fractal surface using an elasto-plastic material model. Dominant micro-scale regular patterns were found to significantly change the contact behavior. Contact areas mainly cluster around the regular pattern. The contribution from the fractal structure is not significant. Under cyclic loading conditions, plastic deformation in the 1st loading/unloading cycle smooth the surface. The subsequent repetitive loading/unloading cycles undergo elastic contact without changing the morphology of the contacting surfaces. The work is expected to shed light on the quality of the switch surface contact as well as the optimum design of RF MEM switch surfaces.

Projection displays and MEMS: timely convergence for a bright future

NASA Astrophysics Data System (ADS)

Hornbeck, Larry J.

1995-09-01

Projection displays and microelectromechanical systems (MEMS) have evolved independently, occasionally crossing paths as early as the 1950s. But the commercially viable use of MEMS for projection displays has been illusive until the recent invention of Texas Instruments Digital Light Processing TM (DLP) technology. DLP technology is based on the Digital Micromirror DeviceTM (DMD) microchip, a MEMS technology that is a semiconductor digital light switch that precisely controls a light source for projection display and hardcopy applications. DLP technology provides a unique business opportunity because of the timely convergence of market needs and technology advances. The world is rapidly moving to an all- digital communications and entertainment infrastructure. In the near future, most of the technologies necessary for this infrastrucutre will be available at the right performance and price levels. This will make commercially viable an all-digital chain (capture, compression, transmission, reception decompression, hearing, and viewing). Unfortunately, the digital images received today must be translated into analog signals for viewing on today's televisions. Digital video is the final link in the all-digital infrastructure and DLP technoogy provides that link. DLP technology is an enabler for digital, high-resolution, color projection displays that have high contrast, are bright, seamless, and have the accuracy of color and grayscale that can be achieved only by digital control. This paper contains an introduction to DMD and DLP technology, including the historical context from which to view their developemnt. The architecture, projection operation, and fabrication are presented. Finally, the paper includes an update about current DMD business opportunities in projection displays and hardcopy.

Low mass MEMS/NEMS switch for a substitute of CMOS transistor using single-walled carbon nanotube thin film

NASA Astrophysics Data System (ADS)

Jang, Min-Woo

Power dissipation is a key factor for mobile devices and other low power applications. Complementary metal oxide semiconductor (CMOS) is the dominant integrated circuit (IC) technology responsible for a large part of this power dissipation. As the minimum feature size of CMOS devices enters into the sub 50 nanometer (nm) regime, power dissipation becomes much worse due to intrinsic physical limits. Many approaches have been studied to reduce power dissipation of deeply scaled CMOS ICs. One possible candidate is the electrostatic electromechanical switch, which could be fabricated with conventional CMOS processing techniques. They have critical advantages compared to CMOS devices such as almost zero standby leakage in the off-state due to the absence of a pn junction and a gate oxide, as well as excellent drive current in the on-state due to a metallic channel. Despite their excellent standby power dissipation, the electrostatic MEMS/NEMS switches have not been considered as a viable replacement for CMOS devices due to their large mechanical delay. Moreover, previous literature reveals that their pull-in voltage and switching speed are strongly proportional to each other. This reduces their potential advantage. However, in this work, we theoretically and experimentally demonstrated that the use of single-walled carbon nanotube (SWNT) with very low mass density and strong mechanical properties could provide a route to move off of the conventional trend with respect to the pull-in voltage / switching speed tradeoff observed in the literature. We fabricated 2-terminal fixed- beam switches with aligned composite SWNT thin films. In this work, layer-by-layer (LbL) self-assembly and dielectrophoresis were selected for aligned-composite SWNT thin film deposition. The dense membranes were successfully patterned to form submicron beams by e-beam lithography and oxygen plasma etching. Fixed-fixed beam switches using these membranes successfully operated with approximately 600 psec switching delay and as low as a 3 V dc pull-in. From this we confirmed that the SWNT-based thin films have the potential to make fast MEMS switches with a low operation voltage due to its low mass density and high stiffness. However, the copolymer caused a serious reliability issue and a copolymer-free SWNT film deposition method was developed by replacing positive copolymer with a dispersion of positively functionalized SWNTs. The electrical and physical properties of pure single-walled carbon nanotube thin films deposited through a copolymer-free LbL self-assembly process are then discussed. The film thickness was proportional to the number of dipping cycles. The film resistivity was estimated as 2.19x10-3 Ω-cm after thermal treatments were performed. The estimated specific contact resistance to gold electrodes was 6.33x10-9 Ω-m2 from contact chain measurements. The fabricated 3-terminal MEMS switches using these films functioned as a beam for multiple switching cycles with a 4.5V pull-in voltage, which was operated like a 2-input NAND gate. The SWNT-based thin film switch is promising for a variety of applications to high-end nanoelectronics and high- performance MEMS/NEMS.

Internal Model-Based Robust Tracking Control Design for the MEMS Electromagnetic Micromirror.

PubMed

Tan, Jiazheng; Sun, Weijie; Yeow, John T W

2017-05-26

The micromirror based on micro-electro-mechanical systems (MEMS) technology is widely employed in different areas, such as scanning, imaging and optical switching. This paper studies the MEMS electromagnetic micromirror for scanning or imaging application. In these application scenarios, the micromirror is required to track the command sinusoidal signal, which can be converted to an output regulation problem theoretically. In this paper, based on the internal model principle, the output regulation problem is solved by designing a robust controller that is able to force the micromirror to track the command signal accurately. The proposed controller relies little on the accuracy of the model. Further, the proposed controller is implemented, and its effectiveness is examined by experiments. The experimental results demonstrate that the performance of the proposed controller is satisfying.

Internal Model-Based Robust Tracking Control Design for the MEMS Electromagnetic Micromirror

PubMed Central

Tan, Jiazheng; Sun, Weijie; Yeow, John T. W.

2017-01-01

The micromirror based on micro-electro-mechanical systems (MEMS) technology is widely employed in different areas, such as scanning, imaging and optical switching. This paper studies the MEMS electromagnetic micromirror for scanning or imaging application. In these application scenarios, the micromirror is required to track the command sinusoidal signal, which can be converted to an output regulation problem theoretically. In this paper, based on the internal model principle, the output regulation problem is solved by designing a robust controller that is able to force the micromirror to track the command signal accurately. The proposed controller relies little on the accuracy of the model. Further, the proposed controller is implemented, and its effectiveness is examined by experiments. The experimental results demonstrate that the performance of the proposed controller is satisfying. PMID:28587105

RF MEMS microswitches design and characterization

NASA Astrophysics Data System (ADS)

Lafontan, Xavier; Dufaza, Christian; Robert, Michel; Perez, Guy; Pressecq, Francis

2000-08-01

This paper presents the work performed in MUMPs on RF MEMS micro-switch. Concepts, design and characterization of switches are studied. The study particularly focuses on the electrical resistance characterization and modelization. The switches developed uses two different principle: overflowed gold and hinged beam. The realized contacts exhibited high on resistance (~20(Omega) ) due to nanoscopics asperities of contacts and insulating interfacial films. Results of a typical contact cleaning method are also presented.

Piezoelectric MEMS switch to activate event-driven wireless sensor nodes

NASA Astrophysics Data System (ADS)

Nogami, H.; Kobayashi, T.; Okada, H.; Makimoto, N.; Maeda, R.; Itoh, T.

2013-09-01

We have developed piezoelectric microelectromechanical systems (MEMS) switches and applied them to ultra-low power wireless sensor nodes, to monitor the health condition of chickens. The piezoelectric switches have ‘S’-shaped piezoelectric cantilevers with a proof mass. Since the resonant frequency of the piezoelectric switches is around 24 Hz, we have utilized their superharmonic resonance to detect chicken movements as low as 5-15 Hz. When the vibration frequency is 4, 6 and 12 Hz, the piezoelectric switches vibrate at 0.5 m s-2 and generate 3-5 mV output voltages with superharmonic resonance. In order to detect such small piezoelectric output voltages, we employ comparator circuits that can be driven at low voltages, which can set the threshold voltage (Vth) from 1 to 31 mV with a 1 mV increment. When we set Vth at 4 mV, the output voltages of the piezoelectric MEMS switches vibrate below 15 Hz with amplitudes above 0.3 m s-2 and turn on the comparator circuits. Similarly, by setting Vth at 5 mV, the output voltages turn on the comparator circuits with vibrations above 0.4 m s-2. Furthermore, setting Vth at 10 mV causes vibrations above 0.5 m s-2 that turn on the comparator circuits. These results suggest that we can select small or fast chicken movements to utilize piezoelectric MEMS switches with comparator circuits.

Comparative study of 2-DOF micromirrors for precision light manipulation

NASA Astrophysics Data System (ADS)

Young, Johanna I.; Shkel, Andrei M.

2001-08-01

Many industry experts predict that the future of fiber optic telecommunications depends on the development of all-optical components for switching of photonic signals from fiber to fiber throughout the networks. MEMS is a promising technology for providing all-optical switching at high speeds with significant cost reductions. This paper reports on the the analysis of two designs for 2-DOF electrostatically actuated MEMS micromirrors for precision controllable large optical switching arrays. The behavior of the micromirror designs is predicted by coupled-field electrostatic and modal analysis using a finite element analysis (FEA) multi-physics modeling software. The analysis indicates that the commonly used gimbal type mirror design experiences electrostatic interference and would therefore be difficult to precisely control for 2-DOF motion. We propose a new design approach which preserves 2-DOF actuation while minimizing electrostatic interference between the drive electrodes and the mirror. Instead of using two torsional axes, we use one actuator which combines torsional and flexural DOFs. A comparative analysis of the conventional gimbal design and the one proposed in this paper is performed.

Eddy-current-damped microelectromechanical switch

DOEpatents

Christenson, Todd R.; Polosky, Marc A.

2007-10-30

A microelectromechanical (MEM) device is disclosed that includes a shuttle suspended for movement above a substrate. A plurality of permanent magnets in the shuttle of the MEM device interact with a metal plate which forms the substrate or a metal portion thereof to provide an eddy-current damping of the shuttle, thereby making the shuttle responsive to changes in acceleration or velocity of the MEM device. Alternately, the permanent magnets can be located in the substrate, and the metal portion can form the shuttle. An electrical switch closure in the MEM device can occur in response to a predetermined acceleration-time event. The MEM device, which can be fabricated either by micromachining or LIGA, can be used for sensing an acceleration or deceleration event (e.g. in automotive applications such as airbag deployment or seat belt retraction).

Eddy-current-damped microelectromechanical switch

DOEpatents

Christenson, Todd R [Albuquerque, NM; Polosky, Marc A [Tijeras, NM

2009-12-15

A microelectromechanical (MEM) device is disclosed that includes a shuttle suspended for movement above a substrate. A plurality of permanent magnets in the shuttle of the MEM device interact with a metal plate which forms the substrate or a metal portion thereof to provide an eddy-current damping of the shuttle, thereby making the shuttle responsive to changes in acceleration or velocity of the MEM device. Alternately, the permanent magnets can be located in the substrate, and the metal portion can form the shuttle. An electrical switch closure in the MEM device can occur in response to a predetermined acceleration-time event. The MEM device, which can be fabricated either by micromachining or LIGA, can be used for sensing an acceleration or deceleration event (e.g. in automotive applications such as airbag deployment or seat belt retraction).

Electrostatic Radio Frequency (RF) Microelectromechanical Systems (MEMS) Switches With Metal Alloy Electric Contacts

DTIC Science & Technology

2004-09-01

Serway , Raymond A. Physics for Scientists and Engineers . New York: Saunders College Publishing, 1986. 141. Sharvin, Y.V. Sov. Phys. JETP , 21 :655 (1965...III. Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 3.1 Micro-Switch Physical Description . . . . . . . . . . . 17 3.2 MEMS...Insertion Loss . . . . . . . . . . . . . . . . . . . . . . . . 56 IMD Intermodulation Distortion . . . . . . . . . . . . . . . . 56 PVD Physical Vapor

Micro environmental sensing device

DOEpatents

Polosky, Marc A.; Lukens, Laurance L.

2006-05-02

A microelectromechanical (MEM) acceleration switch is disclosed which includes a proof mass flexibly connected to a substrate, with the proof mass being moveable in a direction substantially perpendicular to the substrate in response to a sensed acceleration. An electrode on the proof mass contacts one or more electrodes located below the proof mass to provide a switch closure in response to the sensed acceleration. Electrical latching of the switch in the closed position is possible with an optional latching electrode. The MEM acceleration switch, which has applications for use as an environmental sensing device, can be fabricated using micromachining.

RF-MEMS for future mobile applications: experimental verification of a reconfigurable 8-bit power attenuator up to 110 GHz

NASA Astrophysics Data System (ADS)

Iannacci, J.; Tschoban, C.

2017-04-01

RF-MEMS technology is proposed as a key enabling solution for realising the high-performance and highly reconfigurable passive components that future communication standards will demand. In this work, we present, test and discuss a novel design concept for an 8-bit reconfigurable power attenuator, manufactured using the RF-MEMS technology available at the CMM-FBK, in Italy. The device features electrostatically controlled MEMS ohmic switches in order to select/deselect the resistive loads (both in series and shunt configuration) that attenuate the RF signal, and comprises eight cascaded stages (i.e. 8-bit), thus implementing 256 different network configurations. The fabricated samples are measured (S-parameters) from 10 MHz to 110 GHz in a wide range of different configurations, and modelled/simulated with Ansys HFSS. The device exhibits attenuation levels (S21) in the range from  -10 dB to  -60 dB, up to 110 GHz. In particular, S21 shows flatness from 15 dB down to 3-5 dB and from 10 MHz to 50 GHz, as well as fewer linear traces up to 110 GHz. A comprehensive discussion is developed regarding the voltage standing wave ratio, which is employed as a quality indicator for the attenuation levels. The margins of improvement at design level which are needed to overcome the limitations of the presented RF-MEMS device are also discussed.

Parylene-based active micro space radiator with thermal contact switch

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ueno, Ai; Suzuki, Yuji

2014-03-03

Thermal management is crucial for highly functional spacecrafts exposed to large fluctuations of internal heat dissipation and/or thermal boundary conditions. Since thermal radiation is the only means for heat removal, effective control of radiation is required for advanced space missions. In the present study, a MEMS (Micro Electro Mechanical Systems) active radiator using the contact resistance change has been proposed. Unlike previous bulky thermal louvers/shutters, higher fill factor can be accomplished with an array of electrostatically driven micro diaphragms suspended with polymer tethers. With an early prototype developed with parylene MEMS technologies, radiation heat flux enhancement up to 42% hasmore » been achieved.« less

Effectiveness of BaTiO 3 dielectric patches on YBa 2Cu 3O 7 thin films for MEM switches

DOE PAGES

Vargas, J.; Hijazi, Y.; Noel, J.; ...

2014-05-12

A micro-electro-mechanical (MEM) switch built on a superconducting microstrip filter will be utilized to investigate BaTiO 3 dielectric patches for functional switching points of contact. Actuation voltage resulting from the MEM switch provokes static friction between the bridge membrane and BaTiO 3 insulation layer. Furthermore, the dielectric patch crystal structure and roughness affect the ability of repetitively switching cycles and lifetime. We performed a series of experiments using different deposition methods and RF magnetron sputtering was found to be the best deposition process for the BaTiO 3 layer. The effect examination of surface morphology will be presented using characterization techniquesmore » as x-ray diffraction, SEM and AFM for an optimum switching device. The thin film is made of YBa 2Cu 3O 7 deposited on LaAlO 3 substrate by pulsed laser deposition. In our work, the dielectric material sputtering pressure is set at 9.5x10 -6 Torr. The argon gas is released through a mass-flow controller to purge the system prior to deposition. RF power is 85 W at a distance of 9 cm. The behavior of Au membranes built on ultimate BaTiO 3 patches will be shown as part of the results. These novel surface patterns will in turn be used in modelling other RF MEM switch devices such as distributed-satellite communication system operating at cryogenic temperatures.« less

128×128 three-dimensional MEMS optical switch module with simultaneous optical path connection for optical cross-connect systems.

PubMed

Mizukami, Masato; Yamaguchi, Joji; Nemoto, Naru; Kawajiri, Yuko; Hirata, Hirooki; Uchiyama, Shingo; Makihara, Mitsuhiro; Sakata, Tomomi; Shimoyama, Nobuhiro; Oda, Kazuhiro

2011-07-20

A 128×128 three-dimensional MEMS optical switch module and a switching-control algorithm for high-speed connection and optical power stabilization are described. A prototype switch module enables the simultaneous switching of all optical paths. The insertion loss is less than 4.6 dB and is 2.3 dB on average. The switching time is less than 38 ms and is 8 ms on average. We confirmed that the maximum optical power can be obtained and optical power stabilization control is possible. The results confirm that the module is suitable for practical use in optical cross-connect systems. © 2011 Optical Society of America

MEMS switches having non-metallic crossbeams

NASA Technical Reports Server (NTRS)

Scardelletti, Maximillian C (Inventor)

2009-01-01

A RF MEMS switch comprising a crossbeam of SiC, supported by at least one leg above a substrate and above a plurality of transmission lines forming a CPW. Bias is provided by at least one layer of metal disposed on a top surface of the SiC crossbeam, such as a layer of chromium followed by a layer of gold, and extending beyond the switch to a biasing pad on the substrate. The switch utilizes stress and conductivity-controlled non-metallic thin cantilevers or bridges, thereby improving the RF characteristics and operational reliability of the switch. The switch can be fabricated with conventional silicon integrated circuit (IC) processing techniques. The design of the switch is very versatile and can be implemented in many transmission line mediums.

Amorphous SiC as a structural layer in microbridge-based RF MEMS switches for use in software-defined radio

NASA Astrophysics Data System (ADS)

Parro, Rocco J.; Scardelletti, Maximilian C.; Varaljay, Nicholas C.; Zimmerman, Sloan; Zorman, Christian A.

2008-10-01

This paper reports an effort to develop amorphous silicon carbide (a-SiC) films for use in shunt capacitor RF MEMS microbridge-based switches. The films were deposited using methane and silane as the precursor gases. Switches were fabricated using 500 nm and 300 nm-thick a-SiC films to form the microbridges. Switches made from metallized 500 nm-thick SiC films exhibited favorable mechanical performance but poor RF performance. In contrast, switches made from metallized 300 nm-thick SiC films exhibited excellent RF performance but poor mechanical performance. Load-deflection testing of unmetallized and metallized bulk micromachined SiC membranes indicates that the metal layers have a small effect on the Young's modulus of the 500 nm and 300 nm-thick SiC MEMS. As for residual stress, the metal layers have a modest effect on the 500 nm-thick structures, but a significant affect on the residual stress in the 300 nm-thick structures.

Microelectromechanical apparatus for elevating and tilting a platform

DOEpatents

Miller, Samuel Lee; McWhorter, Paul Jackson; Rodgers, Murray Steven; Sniegowski, Jeffry J.; Barnes, Stephen M.

2003-04-08

A microelectromechanical (MEM) apparatus is disclosed which has a platform that can be elevated above a substrate and tilted at an arbitrary angle using a plurality of flexible members which support the platform and control its movement. Each flexible member is further controlled by one or more MEM actuators which act to bend the flexible member. The MEM actuators can be electrostatic comb actuators or vertical zip actuators, or a combination thereof. The MEM apparatus can include a mirror coating to form a programmable mirror for redirecting or switching one or more light beams for use in a projection display. The MEM apparatus with the mirror coating also has applications for switching light beams between optical fibers for use in a local area fiber optic network, or for use in fiber optic telecommunications or data communications systems.

Microelectromechanical apparatus for elevating and tilting a platform

DOEpatents

Miller, Samuel Lee; McWhorter, Paul Jackson; Rodgers, Murray Steven; Sniegowski, Jeffry J.; Barnes, Stephen M.

2004-07-06

A microelectromechanical (MEM) apparatus is disclosed which has a platform that can be elevated above a substrate and tilted at an arbitrary angle using a plurality of flexible members which support the platform and control its movement. Each flexible member is further controlled by one or more MEM actuators which act to bend the flexible member. The MEM actuators can be electrostatic comb actuators or vertical zip actuators, or a combination thereof. The MEM apparatus can include a mirror coating to form a programmable mirror for redirecting or switching one or more light beams for use in a projection display. The MEM apparatus with-the mirror coating also has applications for switching light beams between optical fibers for use in a local area fiber optic network, or for use in fiber optic telecommunications or data communications systems.

Electrical latching of microelectromechanical devices

DOEpatents

Garcia, Ernest J.; Sleefe, Gerard E.

2004-11-02

Methods are disclosed for row and column addressing of an array of microelectromechanical (MEM) devices. The methods of the present invention are applicable to MEM micromirrors or memory elements and allow the MEM array to be programmed and maintained latched in a programmed state with a voltage that is generally lower than the voltage required for electrostatically switching the MEM devices.

MEMS micromirrors for optical switching in multichannel spectrophotometers

NASA Astrophysics Data System (ADS)

Tuantranont, Adisorn; Lomas, Tanom; Bright, Victor M.

2004-04-01

This paper reports for the first time that a novel MEMS-based micromirror switch has successfully demonstrated for optical switching in a multi-channel fiber optics spectrophotometer system. The conventional optomechanical fiber optic switches for multi-channel spectrophotometers available in market are bulky, slow, low numbers of channels and expensive. Our foundry MEMS-based micromirror switch designed for integrating with commercially available spectrophotometers offers more compact devices, increased number of probing channels, higher performance and cheaper. Our MEMS-based micromirror switch is a surface micromachined mirror fabricated through MUMPs foundry. The 280 μm x 280 μm gold coated mirror is suspended by the double-gimbal structure for X and Y axis scanning. Self-assembly by solders is used to elevate the torsion mirror 30 μm over the substrate to achieve large scan angle. The solder self-assembly approach dramatically reduces the time to assembly the switch. The scan mirror is electrostatically controlled by applying voltages. The individual probing signal from each probing head is guided by fibers with collimated lenses and incidents on the center of the mirror. The operating scan angle is in the range of 3.5 degrees with driving voltage of 0-100 V. The fastest switching time of 4 millisecond (1 ms rise time and 3 ms fall time) is measured corresponding to the maximum speed of the mirror of 0.25 kHz when the mirror is scanning at +/- 1.5 degrees. The micromirror switch is packaged with a multi-mode fiber bundle using active alignment technique. A centered fiber is the output fiber that is connected to spectrophotometer. Maximum insertion loss of 5 dB has been obtained. The accuracy of measured spectral data is equivalent to the single channel spectrophotometer with a small degradation on probing signal due to fiber coupling.

Advances in integrated photonic circuits for packet-switched interconnection

NASA Astrophysics Data System (ADS)

Williams, Kevin A.; Stabile, Ripalta

2014-03-01

Sustained increases in capacity and connectivity are needed to overcome congestion in a range of broadband communication network nodes. Packet routing and switching in the electronic domain are leading to unsustainable energy- and bandwidth-densities, motivating research into hybrid solutions: optical switching engines are introduced for massive-bandwidth data transport while the electronic domain is clocked at more modest GHz rates to manage routing. Commercially-deployed optical switching engines using MEMS technologies are unwieldy and too slow to reconfigure for future packet-based networking. Optoelectronic packet-compliant switch technologies have been demonstrated as laboratory prototypes, but they have so far mostly used discretely pigtailed components, which are impractical for control plane development and product assembly. Integrated photonics has long held the promise of reduced hardware complexity and may be the critical step towards packet-compliant optical switching engines. Recently a number of laboratories world-wide have prototyped optical switching circuits using monolithic integration technology with up to several hundreds of integrated optical components per chip. Our own work has focused on multi-input to multi-output switching matrices. Recently we have demonstrated 8×8×8λ space and wavelength selective switches using gated cyclic routers and 16×16 broadband switching chips using monolithic multi-stage networks. We now operate these advanced circuits with custom control planes implemented with FPGAs to explore real time packet routing in multi-wavelength, multi-port test-beds. We review our contributions in the context of state of the art photonic integrated circuit technology and packet optical switching hardware demonstrations.

Investigation of Structures of Microwave Microelectromechanical-System Switches by Taguchi Method

NASA Astrophysics Data System (ADS)

Lai, Yeong-Lin; Lin, Chien-Hung

2007-10-01

The optimal design of microwave microelectromechanical-system (MEMS) switches by the Taguchi method is presented. The structures of the switches are analyzed and optimized in terms of the effective stiffness constant, the maximum von Mises stress, and the natural frequency in order to improve the reliability and the performance of the MEMS switches. There are four factors, each of which has three levels in the Taguchi method for the MEMS switches. An L9(34) orthogonal array is used for the matrix experiments. The characteristics of the experiments are studied by the finite-element method and the analytical method. The responses of the signal-to-noise (S/N) ratios of the characteristics of the switches are investigated. The statistical analysis of variance (ANOVA) is used to interpret the experimental results and decide the significant factors. The final optimum setting, A1B3C1D2, predicts that the effective stiffness constant is 1.06 N/m, the maximum von Mises stress is 76.9 MPa, and the natural frequency is 29.331 kHz. The corresponding switching time is 34 μs, and the pull-down voltage is 9.8 V.

Micromachined sensor for stress measurement and micromechanical study of free-standing thin films for MEMS applications

NASA Astrophysics Data System (ADS)

Zhang, Ping

Microelectromechanical systems (MEMS) have a wide range of applications. In the field of wireless and microwave technology, considerable attention has been given to the development and integration of MEMS-based RF (radio frequency) components. An RF MEMS switch requires low insertion loss, high isolation, and low actuation voltage - electrical aspects that have been extensively studied. The mechanical requirements of the switch, such as low sensitivity to built-in stress and high reliability, greatly depend on the micromechanical properties of the switch materials, and have not been thoroughly explored. RF MEMS switches are typically in the form of a free-standing thin film structure. Large stress gradients and across-wafer stress variations developed during fabrication severely degrade their electrical performance. A micromachined stress measurement sensor has been developed that can potentially be employed for in-situ monitoring of stress evolution and stress variation. The sensors were micromachined using five masks on two wafer levels, each measuring 5x3x1 mm. They function by means of an electron tunneling mechanism, where a 2x2 mm silicon nitride membrane elastically deflects under an applied deflection voltage via an external feedback circuitry. For the current design, the sensors are capable of measuring tensile stresses up to the GPa range under deflection voltages of 50--100 V. Sensor functionality was studied by finite element modeling and a theoretical analysis of square membrane deflection. While the mechanical properties of thin films on substrates have been extensively studied, studies of free-standing thin films have been limited due to the practical difficulties in sample handling and testing. Free-standing Al and Al-Ti thin films specimens have been successfully fabricated and microtensile and stress relaxation tests have been performed using a custom-designed micromechanical testing apparatus. A dedicated TEM (transmission electron microscopy) sample preparation technique allows the investigation of the microstructures of these thin films both before and after mechanical testing to correlate the microstructural findings with the mechanical behavior. Major studies include grain boundary strengthening in pure Al, plastic deformation in pure Al by inhomogeneous deformation and localized grain thinning, solid solution and precipitate strengthening in Al-Ti alloys, and stress relaxation of Al and Al-Ti.

Insulator Charging in RF MEMS Capacitive Switches

DTIC Science & Technology

2005-06-01

and Simulations,” Journal of Microelectromechanical Systems, 8: 208-217 (June 1999). 5. Neaman , Donald. Semiconductor Physics & Devices. Boston...227-230 (2001). 5. Sze, S.M. Semiconductor Devices: Physics and Technology. New York: Wiley, 1985. 6. Neaman , Donald A. Semiconductor Physics...Radiation Response of Hafnium-Silicate Capacitors,” IEEE Transactions on Nuclear Science, 49: 3191-3196 (December 2002). 3. Neaman , D.A

Emerging leadership of surface micromachined MEMS for wavelength switching in telecommunications systems

NASA Astrophysics Data System (ADS)

Staple, Bevan D.; Muller, Lilac; Miller, David C.

2003-01-01

We introduce the Network Photonics" CrossWave as the first commercially-available, MEMS-based wavelength selective switch. The CrossWave combines the functionality of signal de-multiplexing, switching and re-multiplexing in a single all-optical operation using a dispersive element and 1-D MEMS. 1-D MEMS, where micromirrors are configured in a single array with a single mirror per wavelength, are fabricated in a standard surface micromachining process. In this paper we present three generations of micromirror designs. With proper design optimization and process improvements we have demonstrated exceptional mirror flatness (<16.2m-1 curvature), surface error (

Bistable microelectromechanical actuator

DOEpatents

Fleming, James G.

1999-01-01

A bistable microelectromechanical (MEM) actuator is formed on a substrate and includes a stressed membrane of generally rectangular shape that upon release assumes a curvilinear cross-sectional shape due to attachment at a midpoint to a resilient member and at opposing edges to a pair of elongate supports. The stressed membrane can be electrostatically switched between a pair of mechanical states having mirror-image symmetry, with the MEM actuator remaining in a quiescent state after a programming voltage is removed. The bistable MEM actuator according to various embodiments of the present invention can be used to form a nonvolatile memory element, an optical modulator (with a pair of mirrors supported above the membrane and moving in synchronism as the membrane is switched), a switchable mirror (with a single mirror supported above the membrane at the midpoint thereof) and a latching relay (with a pair of contacts that open and close as the membrane is switched). Arrays of bistable MEM actuators can be formed for applications including nonvolatile memories, optical displays and optical computing.

Bistable microelectromechanical actuator

DOEpatents

Fleming, J.G.

1999-02-02

A bistable microelectromechanical (MEM) actuator is formed on a substrate and includes a stressed membrane of generally rectangular shape that upon release assumes a curvilinear cross-sectional shape due to attachment at a midpoint to a resilient member and at opposing edges to a pair of elongate supports. The stressed membrane can be electrostatically switched between a pair of mechanical states having mirror-image symmetry, with the MEM actuator remaining in a quiescent state after a programming voltage is removed. The bistable MEM actuator according to various embodiments of the present invention can be used to form a nonvolatile memory element, an optical modulator (with a pair of mirrors supported above the membrane and moving in synchronism as the membrane is switched), a switchable mirror (with a single mirror supported above the membrane at the midpoint thereof) and a latching relay (with a pair of contacts that open and close as the membrane is switched). Arrays of bistable MEM actuators can be formed for applications including nonvolatile memories, optical displays and optical computing. 49 figs.

Wavelength specific excitation of gold nanoparticle thin-films

NASA Astrophysics Data System (ADS)

Lucas, Thomas M.; James, Kurtis T.; Beharic, Jasmin; Moiseeva, Evgeniya V.; Keynton, Robert S.; O'Toole, Martin G.; Harnett, Cindy K.

2014-01-01

Advances in microelectromechanical systems (MEMS) continue to empower researchers with the ability to sense and actuate at the micro scale. Thermally driven MEMS components are often used for their rapid response and ability to apply relatively high forces. However, thermally driven MEMS often have high power consumption and require physical wiring to the device. This work demonstrates a basis for designing light-powered MEMS with a wavelength specific response. This is accomplished by patterning surface regions with a thin film containing gold nanoparticles that are tuned to have an absorption peak at a particular wavelength. The heating behavior of these patterned surfaces is selected by the wavelength of laser directed at the sample. This method also eliminates the need for wires to power a device. The results demonstrate that gold nanoparticle films are effective wavelength-selective absorbers. This "hybrid" of infrared absorbent gold nanoparticles and MEMS fabrication technology has potential applications in light-actuated switches and other mechanical structures that must bend at specific regions. Deposition methods and surface chemistry will be integrated with three-dimensional MEMS structures in the next phase of this work. The long-term goal of this project is a system of light-powered microactuators for exploring cellular responses to mechanical stimuli, increasing our fundamental understanding of tissue response to everyday mechanical stresses at the molecular level.

CMOS compatible thin-film ALD tungsten nanoelectromechanical devices

NASA Astrophysics Data System (ADS)

Davidson, Bradley Darren

This research focuses on the development of a novel, low-temperature, CMOS compatible, atomic-layer-deposition (ALD) enabled NEMS fabrication process for the development of ALD Tungsten (WALD) NEMS devices. The devices are intended for use in CMOS/NEMS hybrid systems, and NEMS based micro-processors/controllers capable of reliable operation in harsh environments not accessible to standard CMOS technologies. The majority of NEMS switches/devices to date have been based on carbon-nano-tube (CNT) designs. The devices consume little power during actuation, and as expected, have demonstrated actuation voltages much smaller than MEMS switches. Unfortunately, NEMS CNT switches are not typically CMOS integrable due to the high temperatures required for their growth, and their fabrication typically results in extremely low and unpredictable yields. Thin-film NEMS devices offer great advantages over reported CNT devices for several reasons, including: higher fabrication yields, low-temperature (CMOS compatible) deposition techniques like ALD, and increased control over design parameters/device performance metrics, i.e., device geometry. Furthermore, top-down, thin-film, nano-fabrication techniques are better capable of producing complicated device geometries than CNT based processes, enabling the design and development of multi-terminal switches well-suited for low-power hybrid NEMS/CMOS systems as well as electromechanical transistors and logic devices for use in temperature/radiation hard computing architectures. In this work several novel, low-temperature, CMOS compatible fabrication technologies, employing WALD as a structural layer for MEMS or NEMS devices, were developed. The technologies developed are top-down nano-scale fabrication processes based on traditional micro-machining techniques commonly used in the fabrication of MEMS devices. Using these processes a variety of novel WALD NEMS devices have been successfully fabricated and characterized. Using two different WALD fabrication technologies two generations of 2-terminal WALD NEMS switches have been developed. These devices have functional gap heights of 30-50 nm, and actuation voltages typically ranging from 3--5 Volts. Via the extension of a two terminal WALD technology novel 3-terminal WALD NEMS devices were developed. These devices have actuation voltages ranging from 1.5--3 Volts, reliabilities in excess of 2 million cycles, and have been designed to be the fundamental building blocks for WALD NEMS complementary inverters. Through the development of these devices several advancements in the modeling and design of thin-film NEMS devices were achieved. A new model was developed to better characterize pre-actuation currents commonly measured for NEMS switches with nano-scale gate-to-source gap heights. The developed model is an extension of the standard field-emission model and considers the electromechanical response, and electric field effects specific to thin-film NEMS switches. Finally, a multi-physics FEM/FD based model was developed to simulate the dynamic behavior of 2 or 3-terminal electrostatically actuated devices whose electrostatic domains have an aspect ratio on the order of 10-3. The model uses a faux-Lagrangian finite difference method to solve Laplaces equation in a quasi-statatically deforming domain. This model allows for the numerical characterization and design of thin-film NEMS devices not feasible using typical non-specialized BEM/FEM based software. Using this model several novel and feasible designs for fixed-fixed 3-terminal WALD NEMS switches capable for the construction of complementary inverters were discovered.

Advanced RF Front End Technology

NASA Technical Reports Server (NTRS)

Herman, M. I.; Valas, S.; Katehi, L. P. B.

2001-01-01

The ability to achieve low-mass low-cost micro/nanospacecraft for Deep Space exploration requires extensive miniaturization of all subsystems. The front end of the Telecommunication subsystem is an area in which major mass (factor of 10) and volume (factor of 100) reduction can be achieved via the development of new silicon based micromachined technology and devices. Major components that make up the front end include single-pole and double-throw switches, diplexer, and solid state power amplifier. JPL's Center For Space Microsystems - System On A Chip (SOAC) Program has addressed the challenges of front end miniaturization (switches and diplexers). Our objectives were to develop the main components that comprise a communication front end and enable integration in a single module that we refer to as a 'cube'. In this paper we will provide the latest status of our Microelectromechanical System (MEMS) switches and surface micromachined filter development. Based on the significant progress achieved we can begin to provide guidelines of the proper system insertion for these emerging technologies. Additional information is contained in the original extended abstract.

MEMS for Practical Applications

NASA Astrophysics Data System (ADS)

Esashi, Masayoshi

Silicon MEMS as electrostatically levitated rotational gyroscopes and 2D optical scanners, and wafer level packaged devices as integrated capacitive pressure sensors and MEMS switches are described. MEMS which use non-silicon materials as LTCC with electrical feedthrough, SiC and LiNbO3 for probe cards for wafer-level burn-in test, molds for glass press molding and SAW wireless passive sensors respectively are also described.

High Isolation Single-Pole Four-Throw RF MEMS Switch Based on Series-Shunt Configuration

PubMed Central

Khaira, Navjot

2014-01-01

This paper presents a novel design of single-pole four-throw (SP4T) RF-MEMS switch employing both capacitive and ohmic switches. It is designed on high-resistivity silicon substrate and has a compact area of 1.06 mm2. The series or ohmic switches have been designed to provide low insertion loss with good ohmic contact. The pull-in voltage for ohmic switches is calculated to be 7.19 V. Shunt or capacitive switches have been used in each port to improve the isolation for higher frequencies. The proposed SP4T switch provides excellent RF performances with isolation better than 70.64 dB and insertion loss less than 0.72 dB for X-band between the input port and each output port. PMID:24711730

Novel analytical model for optimizing the pull-in voltage in a flexured MEMS switch incorporating beam perforation effect

NASA Astrophysics Data System (ADS)

Guha, K.; Laskar, N. M.; Gogoi, H. J.; Borah, A. K.; Baishnab, K. L.; Baishya, S.

2017-11-01

This paper presents a new method for the design, modelling and optimization of a uniform serpentine meander based MEMS shunt capacitive switch with perforation on upper beam. The new approach is proposed to improve the Pull-in Voltage performance in a MEMS switch. First a new analytical model of the Pull-in Voltage is proposed using the modified Mejis-Fokkema capacitance model taking care of the nonlinear electrostatic force, the fringing field effect due to beam thickness and etched holes on the beam simultaneously followed by the validation of same with the simulated results of benchmark full 3D FEM solver CoventorWare in a wide range of structural parameter variations. It shows a good agreement with the simulated results. Secondly, an optimization method is presented to determine the optimum configuration of switch for achieving minimum Pull-in voltage considering the proposed analytical mode as objective function. Some high performance Evolutionary Optimization Algorithms have been utilized to obtain the optimum dimensions with less computational cost and complexity. Upon comparing the applied algorithms between each other, the Dragonfly Algorithm is found to be most suitable in terms of minimum Pull-in voltage and higher convergence speed. Optimized values are validated against the simulated results of CoventorWare which shows a very satisfactory results with a small deviation of 0.223 V. In addition to these, the paper proposes, for the first time, a novel algorithmic approach for uniform arrangement of square holes in a given beam area of RF MEMS switch for perforation. The algorithm dynamically accommodates all the square holes within a given beam area such that the maximum space is utilized. This automated arrangement of perforation holes will further improve the computational complexity and design accuracy of the complex design of perforated MEMS switch.

Application of RF-MEMS-Based Split Ring Resonators (SRRs) to the Implementation of Reconfigurable Stopband Filters: A Review

PubMed Central

Martín, Ferran; Bonache, Jordi

2014-01-01

In this review paper, several strategies for the implementation of reconfigurable split ring resonators (SRRs) based on RF-MEMS switches are presented. Essentially three types of RF-MEMS combined with split rings are considered: (i) bridge-type RF-MEMS on top of complementary split ring resonators CSRRs; (ii) cantilever-type RF-MEMS on top of SRRs; and (iii) cantilever-type RF-MEMS integrated with SRRs (or RF-MEMS SRRs). Advantages and limitations of these different configurations from the point of view of their potential applications for reconfigurable stopband filter design are discussed, and several prototype devices are presented. PMID:25474378

Low-Loss, High-Isolation Microwave Microelectromechanical Systems (MEMS) Switches Being Developed

NASA Technical Reports Server (NTRS)

Ponchak, George E.

2002-01-01

Switches, electrical components that either permit or prevent the flow of electricity, are the most important and widely used electrical devices in integrated circuits. In microwave systems, switches are required for switching between the transmitter and receiver; in communication systems, they are needed for phase shifters in phased-array antennas, for radar and communication systems, and for the new class of digital or software definable radios. Ideally, switches would be lossless devices that did not depend on the electrical signal's frequency or power, and they would not consume electrical power to change from OFF to ON or to maintain one of these two states. Reality is quite different, especially at microwave frequencies. Typical switches in microwave integrated circuits are pin diodes or gallium arsenide (GaAs) field-effect transistors that are nonlinear, with characteristics that depend on the power of the signal. In addition, they are frequency-dependent, lossy, and require electrical power to maintain a certain state. A new type of component has been developed that overcomes most of these technical difficulties. Microelectromechanical (MEMS) switches rely on mechanical movement as a response to an applied electrical force to either transmit or reflect electrical signal power. The NASA Glenn Research Center has been actively developing MEMS for microwave applications for over the last 5 years. Complete fabrication procedures have been developed so that the moving parts of the switch can be released with near 100-percent yield. Moreover, the switches fabricated at Glenn have demonstrated state-of-the-art performance. A typical MEMS switch is shown. The switch extends over the signal and ground lines of a finite ground coplanar waveguide, a commonly used microwave transmission line. In the state shown, the switch is in the UP state and all the microwave power traveling along the transmission line proceeds unimpeded. When a potential difference is applied between the cantilever and the transmission line, the cantilever is pulled downward until it connects the signal line to the ground planes, creating a short circuit. In this state, all the microwave power is reflected. The graph shows the measured performance of the switch, which has less than 0.1 dB of insertion loss and greater than 30dB of isolation. These switches consume negligible electrical power and are extremely linear. Additional research is required to address reliability and to increase the switching speed.

Design of DC-contact RF MEMS switch with temperature stability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Junfeng; Nanjing Electronic Devices Institute, Nanjing, 210016; Li, Zhiqun, E-mail: zhiqunli@seu.edu.cn

In order to improve the temperature stability of DC-contact RF MEMS switch, a thermal buckle-beam structure is implemented. The stability of the switch pull-in voltage versus temperature is not only improved, but also the impact of stress and stress gradient on the drive voltage is suppressed. Test results show that the switch pull-in voltage is less sensitive to temperature between -20 °C and 100 °C. The variable rate of pull-in voltage to temperature is about -120 mV/°C. The RF performance of the switch is stable, and the isolation is almost independent of temperature. After being annealed at 280 °C formore » 12 hours, our switch samples, which are suitable for packaging, have less than 1.5% change in the rate of pull-in voltage.« less

A learnable parallel processing architecture towards unity of memory and computing

NASA Astrophysics Data System (ADS)

Li, H.; Gao, B.; Chen, Z.; Zhao, Y.; Huang, P.; Ye, H.; Liu, L.; Liu, X.; Kang, J.

2015-08-01

Developing energy-efficient parallel information processing systems beyond von Neumann architecture is a long-standing goal of modern information technologies. The widely used von Neumann computer architecture separates memory and computing units, which leads to energy-hungry data movement when computers work. In order to meet the need of efficient information processing for the data-driven applications such as big data and Internet of Things, an energy-efficient processing architecture beyond von Neumann is critical for the information society. Here we show a non-von Neumann architecture built of resistive switching (RS) devices named “iMemComp”, where memory and logic are unified with single-type devices. Leveraging nonvolatile nature and structural parallelism of crossbar RS arrays, we have equipped “iMemComp” with capabilities of computing in parallel and learning user-defined logic functions for large-scale information processing tasks. Such architecture eliminates the energy-hungry data movement in von Neumann computers. Compared with contemporary silicon technology, adder circuits based on “iMemComp” can improve the speed by 76.8% and the power dissipation by 60.3%, together with a 700 times aggressive reduction in the circuit area.

A learnable parallel processing architecture towards unity of memory and computing.

PubMed

Li, H; Gao, B; Chen, Z; Zhao, Y; Huang, P; Ye, H; Liu, L; Liu, X; Kang, J

2015-08-14

Developing energy-efficient parallel information processing systems beyond von Neumann architecture is a long-standing goal of modern information technologies. The widely used von Neumann computer architecture separates memory and computing units, which leads to energy-hungry data movement when computers work. In order to meet the need of efficient information processing for the data-driven applications such as big data and Internet of Things, an energy-efficient processing architecture beyond von Neumann is critical for the information society. Here we show a non-von Neumann architecture built of resistive switching (RS) devices named "iMemComp", where memory and logic are unified with single-type devices. Leveraging nonvolatile nature and structural parallelism of crossbar RS arrays, we have equipped "iMemComp" with capabilities of computing in parallel and learning user-defined logic functions for large-scale information processing tasks. Such architecture eliminates the energy-hungry data movement in von Neumann computers. Compared with contemporary silicon technology, adder circuits based on "iMemComp" can improve the speed by 76.8% and the power dissipation by 60.3%, together with a 700 times aggressive reduction in the circuit area.

Gold-based thin multilayers for ohmic contacts in RF-MEMS switches

NASA Astrophysics Data System (ADS)

Mulloni, V.; Iannacci, J.; Bartali, R.; Micheli, V.; Colpo, S.; Laidani, N.; Margesin, B.

2011-06-01

In RF-MEMS switches many reliability issues are related to the metal contacts in the switching area. The characteristics of this contact influence not only contact resistance and insertion loss, but also the most relevant switch failure mechanisms that are wear of ohmic contact, adhesion and stiction. Gold is widely used for this purpose because of its good conductivity and chemical inertness, but is a soft metal, and the development of hard contact materials with low resistivity is of great interest for RF-MEMS switch reliability. It is possible to increase the contact hardness preserving the convenient gold properties alternating gold layers with thin layers of different metals. The material becomes harder not only by simple alloying but also by the presence of interfaces which act as barriers for mechanical dislocation migration. A detailed study of mechanical, electrical and morphological properties of gold-chromium, gold-platinum and gold-palladium multilayers is presented and discussed. It is found that the annealing treatments are important for tuning hardness values, and a careful choice of the alloying metal is essential when the material is inserted in a real switch fabrication cycle, because hardness improvements can vanish during oxygen plasma treatments usually involved in RF-switches fabrication. Platinum is the only metal tested that is unaffected by oxidation, and also modifies the chromium adhesion layer diffusion on the contact surface.

Cost-effective method of manufacturing a 3D MEMS optical switch

NASA Astrophysics Data System (ADS)

Carr, Emily; Zhang, Ping; Keebaugh, Doug; Chau, Kelvin

2009-02-01

growth of data and video transport networks. All-optical switching eliminates the need for optical-electrical conversion offering the ability to switch optical signals transparently: independent of data rates, formats and wavelength. It also provides network operators much needed automation capabilities to create, monitor and protect optical light paths. To further accelerate the market penetration, it is necessary to identify a path to reduce the manufacturing cost significantly as well as enhance the overall system performance, uniformity and reliability. Currently, most MEMS optical switches are assembled through die level flip-chip bonding with either epoxies or solder bumps. This is due to the alignment accuracy requirements of the switch assembly, defect matching of individual die, and cost of the individual components. In this paper, a wafer level assembly approach is reported based on silicon fusion bonding which aims to reduce the packaging time, defect count and cost through volume production. This approach is successfully demonstrated by the integration of two 6-inch wafers: a mirror array wafer and a "snap-guard" wafer, which provides a mechanical structure on top of the micromirror to prevent electrostatic snap-down. The direct silicon-to-silicon bond eliminates the CTEmismatch and stress issues caused by non-silicon bonding agents. Results from a completed integrated switch assembly will be presented, which demonstrates the reliability and uniformity of some key parameters of this MEMS optical switch.

Advancing MEMS Technology Usage through the MUMPS (Multi-User MEMS Processes) Program

NASA Technical Reports Server (NTRS)

Koester, D. A.; Markus, K. W.; Dhuler, V.; Mahadevan, R.; Cowen, A.

1995-01-01

In order to help provide access to advanced micro-electro-mechanical systems (MEMS) technologies and lower the barriers for both industry and academia, the Microelectronic Center of North Carolina (MCNC) and ARPA have developed a program which provides users with access to both MEMS processes and advanced electronic integration techniques. The four distinct aspects of this program, the multi-user MEMS processes (MUMP's), the consolidated micro-mechanical element library, smart MEMS, and the MEMS technology network are described in this paper. MUMP's is an ARPA-supported program created to provide inexpensive access to MEMS technology in a multi-user environment. It is both a proof-of-concept and educational tool that aids in the development of MEMS in the domestic community. MUMP's technologies currently include a 3-layer poly-silicon surface micromachining process and LIGA (lithography, electroforming, and injection molding) processes that provide reasonable design flexibility within set guidelines. The consolidated micromechanical element library (CaMEL) is a library of active and passive MEMS structures that can be downloaded by the MEMS community via the internet. Smart MEMS is the development of advanced electronics integration techniques for MEMS through the application of flip chip technology. The MEMS technology network (TechNet) is a menu of standard substrates and MEMS fabrication processes that can be purchased and combined to create unique process flows. TechNet provides the MEMS community greater flexibility and enhanced technology accessibility.

Fiber-optic beam control systems using microelectromechanical systems

NASA Astrophysics Data System (ADS)

Sumriddetchkajorn, Sarun

This dissertation, for the first time, proposes, studies, and experimentally demonstrated novel fiber-optic beam control systems based on the use of microelectromechanical system (MEMS) technology in which the miniaturized versions of mechanical systems can be obtained. Beam control modules include optical add/drop filters, optical switches, variable photonic delay lines (VPDLs), and variable optical attenuators (VOAs). The optical add/drop filter functions as a multiwavelength optical switch that offers the ability to drop and add a certain number of desired wavelengths at an intermediate location where access to all the propagating optical channels is not required between transmission terminals. The VOA can also be used in networks where stocking and tracking of fixed attenuators is difficult. Other specific applications of the VOA are optical gain equalization and polarization dependent loss and gain compensation required in high data-rate wavelength division multiplexed (WDM) lightwave systems. A VPDL can be used to adjust timing amongst multiwavelength optical signals in order to reduce timing jitter and burst traffic in photonic packet switching and parallel signal processing systems. In this dissertation, a small tilt micromirror device is proposed for the implementation of all fiber-optic beam control modules. In particular, the macro-pixel approach where several micromirrors are used to manipulate the desired optical beam is introduced to realize high speed and fault tolerant beam control modules. To eliminate the need of careful optical alignment, an all fiber-connectorized multiwavelength optical switch structure is presented and experimentally demonstrated by using a fiber-loop mirror concept with polarization control. In addition, liquid crystal (LC) devices are studied and are used to implement a compact retro- reflective 2 x 2 fiber-optic switch. Compared to MEMS- based mirror technology, the LC technology is more sensitive to temperature, thereby inappropriate to deploy in a harsh environment. With the benefit provided by WDM systems, wavelength sensitive fiber-optic beam controllers are proposed, offering wavelength sensitive time delay and amplitude controls that can be applied in several applications ranging from optical communications to high speed parallel signal processing. (Abstract shortened by UMI.)

A Ku band 5 bit MEMS phase shifter for active electronically steerable phased array applications

NASA Astrophysics Data System (ADS)

Sharma, Anesh K.; Gautam, Ashu K.; Farinelli, Paola; Dutta, Asudeb; Singh, S. G.

2015-03-01

The design, fabrication and measurement of a 5 bit Ku band MEMS phase shifter in different configurations, i.e. a coplanar waveguide and microstrip, are presented in this work. The development architecture is based on the hybrid approach of switched and loaded line topologies. All the switches are monolithically manufactured on a 200 µm high resistivity silicon substrate using 4 inch diameter wafers. The first three bits (180°, 90° and 45°) are realized using switched microstrip lines and series ohmic MEMS switches whereas the fourth and fifth bits (22.5° and 11.25°) consist of microstrip line sections loaded by shunt ohmic MEMS devices. Individual bits are fabricated and evaluated for performance and the monolithic device is a 5 bit Ku band (16-18 GHz) phase shifter with very low average insertion loss of the order of 3.3 dB and a return loss better than 15 dB over the 32 states with a chip area of 44 mm2. A total phase shift of 348.75° with phase accuracy within 3° is achieved over all of the states. The performance of individual bits has been optimized in order to achieve an integrated performance so that they can be implemented into active electronically steerable antennas for phased array applications.

Design and simulation of RF MEMS SPST shunt and SPDT shunt-shunt switches for X-band and Ku-band applications

NASA Astrophysics Data System (ADS)

Lenka, Manas K.; Sharma, Amit; Sharma, Jaibir; DasGupta, Amitava

2012-10-01

This paper describes the design and simulation of RF MEMS SPST shunt and SPDT shunt-shunt switches with modified coplanar waveguide (CPW) configuration for X-band and Ku-band applications exhibiting high isolation and low insertion loss. By modifying the basic CPW structure for a six-strip membrane having length 720 μm, the resonant frequency can be reduced from 33.5 GHz to 13.5 GHz with isolation as high as -30 dB(-63 dB at resonant frequency) in Ku-band. Similar results are also found in case SPST and SPDT switches with other membrane types.

Optical switch based on thermocapillarity

NASA Astrophysics Data System (ADS)

Sakata, Tomomi; Makihara, Mitsuhiro; Togo, Hiroyoshi; Shimokawa, Fusao; Kaneko, Kazumasa

2001-11-01

Space-division optical switches are essential for the protection, optical cross-connects (OXCs), and optical add/drop multiplexers (OADMs) needed in future fiber-optic communication networks. For applications in these areas, we proposed a thermocapillarity switch called oil-latching interfacial-tension variation effect (OLIVE) switch. An OLIVE switch is a micro-mechanical optical switch fabricated on planar lightwave circuits (PLC) using micro-electro-mechanical systems (MEMS) technology. It consists of a crossing waveguide that has a groove at each crossing point and a pair of microheaters. The groove is partially filled with the refractive-index-matching liquid, and optical signals are switched according to the liquid's position in the groove, i.e., whether it is passing straight through the groove or reflecting at the sidewall of the groove. The liquid is driven by thermocapillarity and latched by capillarity. Using the total internal reflection to switch the optical path, the OLIVE switch exhibits excellent optical characteristics, such as high transparency (insertion loss: < 2 dB), high extinction ratio (> 50 dB), and low crosstalk (< -50 dB). Moreover, since this switch has a simple structure and bi-stability, it has wide variety of applications in wavelength division multiplexing (WDM) networks.

Conception, fabrication and characterization of a silicon based MEMS inertial switch with a threshold value of 5 g

NASA Astrophysics Data System (ADS)

Zhang, Fengtian; Wang, Chao; Yuan, Mingquan; Tang, Bin; Xiong, Zhuang

2017-12-01

Most of the MEMS inertial switches developed in recent years are intended for shock and impact sensing with a threshold value above 50 g. In order to follow the requirement of detecting linear acceleration signal at low-g level, a silicon based MEMS inertial switch with a threshold value of 5 g was designed, fabricated and characterized. The switch consisted of a large proof mass, supported by circular spiral springs. An analytical model of the structure stiffness of the proposed switch was derived and verified by finite-element simulation. The structure fabrication was based on a customized double-buried layer silicon-on-insulator wafer and encapsulated by glass wafers. The centrifugal experiment and nanoindentation experiment were performed to measure the threshold value as well as the structure stiffness. The actual threshold values were measured to be 0.1-0.3 g lower than the pre-designed value of 5 g due to the dimension loss during non-contact lithography processing. Concerning the reliability assessment, a series of environmental experiments were conducted and the switches remained operational without excessive errors. However, both the random vibration and the shock tests indicate that the metal particles generated during collision of contact parts might affect the contact reliability and long-time stability. According to the conclusion reached in this report, an attentive study on switch contact behavior should be included in future research.

Power MEMS Development

DTIC Science & Technology

2010-08-31

circuit breakers for testing and analysis in ONR laboratories. Task 1.2 Contributors: Sunny Kedia, Shinzo Onishi , Scott Samson, Drew Hanser Task 1.2...HEAT SINK FOR HIGH-POWER MEMS SWITCH APPLICATIONS (TASK 1.3) Contributors: Priscila Spagnol, Shinzo Onishi , Drew Hanser, Weidong Wang, Sunny Kedia

Microelectromechanical systems for experimental physics and optical telecommunications

NASA Astrophysics Data System (ADS)

Aksyuk, Vladimir Anatolyevich

1999-12-01

Micro-Electro-Mechanical Systems (MEMS) are an emerging technology, which, when applied to the field of physical sensors, offers not only an obvious advantage of being small and cheap, but more importantly, provides some unique experimental opportunities. These are based on the way physical properties scale with decreasing size. This thesis discusses these basic principles and corresponding advantages and limitations of MEMS technology and presents several experiments in which micromachines are used to do physical measurements that could not be done before. Three types of micromechanical magnetometers are demonstrated. When compared to the state of the art traditional techniques they show greater sensitivity, faster response and can be applied over a wider range of experimental conditions. The high-Q micromechanical torsional oscillator magnetometer is used to observe mesoscopic vortex physics, including single flux lines penetrating into a type-II superconductor just above the first critical field. The Faraday balance ``Trampoline'' magnetometer combines high sensitivity, high bandwidth and can be operated in a wide temperature range. It is used in both high pulsed magnetic fields to record deHaas-vanAlphen oscillations and in DC magnetic fields for magnetization measurements at temperatures down to 100mK. The high sensitivity DC torque magnetometer offers yet higher sensitivity and can be used for a variety of magnetization measurements. Several other MEMS devices for physics and telecommunications applications are presented, including a micromachined near field scanning optical microscope, MEMS fiberoptic switches and large-area large-angle scanners. They provide examples of complex functionality that can be achieved with micromechanics by combining sensors with inherently low-power electrostatic actuators. The optically powered optical power limiter demonstrates the possibility of operating MEMS with optical rather than electrical power.

Micro-Ball-Lens Optical Switch Driven by SMA Actuator

NASA Technical Reports Server (NTRS)

Yang, Eui-Hyeok

2003-01-01

The figure is a simplified cross section of a microscopic optical switch that was partially developed at the time of reporting the information for this article. In a fully developed version, light would be coupled from an input optical fiber to one of two side-by-side output optical fibers. The optical connection between the input and the selected output fiber would be made via a microscopic ball lens. Switching of the optical connection from one output fiber to another would be effected by using a pair of thin-film shape-memory-alloy (SMA) actuators to toggle the lens between two resting switch positions. There are many optical switches some made of macroscopic parts by conventional fabrication techniques and some that are microfabricated and, hence, belong to the class of microelectromechanical systems (MEMS). Conventionally fabricated optical switches tend to be expensive. MEMS switches can be mass-produced at relatively low cost, but their attractiveness has been diminished by the fact that, heretofore, MEMS switches have usually been found to exhibit high insertion losses. The present switch is intended to serve as a prototype of low-loss MEMS switches. In addition, this is the first reported SMA-based optical switch. The optical fibers would be held in V grooves in a silicon frame. The lens would have a diameter of 1 m; it would be held by, and positioned between, the SMA actuators, which would be made of thin films of TiNi alloy. Although the SMA actuators are depicted here as having simple shapes for the sake of clarity of illustration, the real actuators would have complex, partly net-like shapes. With the exception of the lens and the optical fibers, the SMA actuators and other components of the switch would be made by microfabrication techniques. The components would be assembled into a sandwich structure to complete the fabrication of the switch. To effect switching, an electric current would be passed through one of the SMA actuators to heat it above its transition temperature, thereby causing it to deform to a different "remembered" shape. The two SMA actuators would be stiff enough that once switching had taken place and the electrical current was turned off, the lens would remain latched in the most recently selected position. In a test, the partially developed switch exhibited an insertion loss of only -1.9 dB and a switching contrast of 70 dB. One the basis of prior research on SMA actuators and assuming a lens displacement of 125 m between extreme positions, it has been estimated that the fully developed switch would be capable of operating at a frequency as high as 10 Hz.

Nonlinear-Based MEMS Sensors and Active Switches for Gas Detection.

PubMed

Bouchaala, Adam; Jaber, Nizar; Yassine, Omar; Shekhah, Osama; Chernikova, Valeriya; Eddaoudi, Mohamed; Younis, Mohammad I

2016-05-25

The objective of this paper is to demonstrate the integration of a MOF thin film on electrostatically actuated microstructures to realize a switch triggered by gas and a sensing algorithm based on amplitude tracking. The devices are based on the nonlinear response of micromachined clamped-clamped beams. The microbeams are coated with a metal-organic framework (MOF), namely HKUST-1, to achieve high sensitivity. The softening and hardening nonlinear behaviors of the microbeams are exploited to demonstrate the ideas. For gas sensing, an amplitude-based tracking algorithm is developed to quantify the captured quantity of gas. Then, a MEMS switch triggered by gas using the nonlinear response of the microbeam is demonstrated. Noise analysis is conducted, which shows that the switch has high stability against thermal noise. The proposed switch is promising for delivering binary sensing information, and also can be used directly to activate useful functionalities, such as alarming.

Nonlinear-Based MEMS Sensors and Active Switches for Gas Detection

PubMed Central

Bouchaala, Adam; Jaber, Nizar; Yassine, Omar; Shekhah, Osama; Chernikova, Valeriya; Eddaoudi, Mohamed; Younis, Mohammad I.

2016-01-01

The objective of this paper is to demonstrate the integration of a MOF thin film on electrostatically actuated microstructures to realize a switch triggered by gas and a sensing algorithm based on amplitude tracking. The devices are based on the nonlinear response of micromachined clamped-clamped beams. The microbeams are coated with a metal-organic framework (MOF), namely HKUST-1, to achieve high sensitivity. The softening and hardening nonlinear behaviors of the microbeams are exploited to demonstrate the ideas. For gas sensing, an amplitude-based tracking algorithm is developed to quantify the captured quantity of gas. Then, a MEMS switch triggered by gas using the nonlinear response of the microbeam is demonstrated. Noise analysis is conducted, which shows that the switch has high stability against thermal noise. The proposed switch is promising for delivering binary sensing information, and also can be used directly to activate useful functionalities, such as alarming. PMID:27231914

Controlling Casimir force via coherent driving field

NASA Astrophysics Data System (ADS)

Ahmad, Rashid; Abbas, Muqaddar; Ahmad, Iftikhar; Qamar, Sajid

2016-04-01

A four level atom-field configuration is used to investigate the coherent control of Casimir force between two identical plates made up of chiral atomic media and separated by vacuum of width d. The electromagnetic chirality-induced negative refraction is obtained via atomic coherence. The behavior of Casimir force is investigated using Casimir-Lifshitz formula. It is noticed that Casimir force can be switched from repulsive to attractive and vice versa via coherent control of the driving field. This switching feature provides new possibilities of using the repulsive Casimir force in the development of new emerging technologies, such as, micro-electro-mechanical and nano-electro-mechanical systems, i.e., MEMS and NEMS, respectively.

Design of a Class of Antennas Utilizing MEMS, EBG and Septum Polarizers including Near-field Coupling Analysis

NASA Astrophysics Data System (ADS)

Kim, Ilkyu

Recent developments in mobile communications have led to an increased appearance of short-range communications and high data-rate signal transmission. New technologies provides the need for an accurate near-field coupling analysis and novel antenna designs. An ability to effectively estimate the coupling within the near-field region is required to realize short-range communications. Currently, two common techniques that are applicable to the near-field coupling problem are 1) integral form of coupling formula and 2) generalized Friis formula. These formulas are investigated with an emphasis on straightforward calculation and accuracy for various distances between the two antennas. The coupling formulas are computed for a variety of antennas, and several antenna configurations are evaluated through full-wave simulation and indoor measurement in order to validate these techniques. In addition, this research aims to design multi-functional and high performance antennas based on MEMS (Microelectromechanical Systems) switches, EBG (Electromagnetic Bandgap) structures, and septum polarizers. A MEMS switch is incorporated into a slot loaded patch antenna to attain frequency reconfigurability. The resonant frequency of the patch antenna can be shifted using the MEM switch, which is actuated by the integrated bias networks. Furthermore, a high gain base-station antenna utilizing beam-tilting is designed to maximize gain for tilted beam applications. To realize this base-station antenna, an array of four dipole-EBG elements is constructed to implement a fixed down-tilt main beam with application in base station arrays. An improvement of the operating range with the EBG-dipole array is evaluated using a simple linkbudget analysis. The septum polarizer has been widely used in circularly polarized antenna systems due to its simple and compact design and high quality of circularity. In this research, the sigmoid function is used to smoothen the edge in the septum design, which makes it suitable for HPM systems. The PSO (Particle Swarm Optimization) technique is applied to the septum design to achieve a high performance antenna design. The electric field intensity above the septum is evaluated through the simulation and its properties are compared to simple half-plane scattering phenomena.

Ku to V-band 4-bit MEMS phase shifter bank using high isolation SP4T switches and DMTL structures

NASA Astrophysics Data System (ADS)

Dey, Sukomal; Koul, Shiban K.; Poddar, Ajay K.; Rohde, Ulrich L.

2017-10-01

This work presents a micro-electro-mechanical system (MEMS) based on a wide-band 4-bit phase shifter using two back-to-back single-pole-four-throw (SP4T) switches and four different distributed MEMS transmission line (DMTL) structures that are implemented on 635 µm alumina substrate using surface micromachining process. An SP4T switch is designed with a series-shunt configuration and it demonstrates an average return loss of  >17 dB, an insertion loss of  <1.97 dB and maximum isolation of  >28 dB up to 60 GHz. A maximum area of the SP4T switch is ~0.76 mm2. Single-pole-single-throw and SP4T switches are capable of handling 1 W of radio frequency (RF) power up to  >100 million cycles at 25° C; they can even sustained up to  >70 million cycles with 1 W at 85 °C. The proposed wide-band phase shifter works at 17 GHz (Ku-band), 25 GHz (K-band), 35 GHz (Ka-band) and 60 GHz (V-band) frequencies. Finally,a 4-bit phase shifter demonstrates an average insertion loss of  <6 dB, return loss of  >10 dB and maximum phase error of ~3.8° at 60 GHz frequency over 500 MHz bandwidth. Total area of the fabricated device is ~11 mm2. In addition, the proposed device works well up to  >107 cycles with 1 W of RF power. To the best of the author’s knowledge, this is the best reported wide-band MEMS 4-bit phase shifter in the literature that works with a constant resolution.

Fabrication and analysis of radiofrequency MEMS series capacitive single-pole double-throw switch

NASA Astrophysics Data System (ADS)

Bansal, Deepak; Bajpai, Anuroop; Kumar, Prem; Kaur, Maninder; Rangra, Kamaljit

2016-10-01

A compact radiofrequency (RF) MEMS single-pole double-throw (SPDT) switch based on series capacitive configuration is proposed. The critical process parameters are analyzed to improve the fabrication process. A technique of cold-hot thermal shock for lift-off method is explored. The residual stress in the structure is quantified by lancet test structures that come out to be 51 MPa. Effect of residual stress on actuation voltage is explored, which changes its value from 24 to 22 V. Resonance frequency and switching speed of the switch are 11 kHz and 44 μs, respectively, measured using laser Doppler vibrometer. Measured bandwidth of the SPDT switch is 20 GHz (5 to 25 GHz), which is verified with finite element method simulations in high frequency structure simulator©; and an equivalent LCR circuit in advanced design system©;. Insertion loss of the switch lies in -0.1 to -0.5 dB with isolation better than -20 dB for the above-mentioned bandwidth.

Critical issues for the application of integrated MEMS/CMOS technologies to inertial measurement units

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, J.H.; Ellis, J.R.; Montague, S.

1997-03-01

One of the principal applications of monolithically integrated micromechanical/microelectronic systems has been accelerometers for automotive applications. As integrated MEMS/CMOS technologies such as those developed by U.C. Berkeley, Analog Devices, and Sandia National Laboratories mature, additional systems for more sensitive inertial measurements will enter the commercial marketplace. In this paper, the authors will examine key technology design rules which impact the performance and cost of inertial measurement devices manufactured in integrated MEMS/CMOS technologies. These design parameters include: (1) minimum MEMS feature size, (2) minimum CMOS feature size, (3) maximum MEMS linear dimension, (4) number of mechanical MEMS layers, (5) MEMS/CMOS spacing.more » In particular, the embedded approach to integration developed at Sandia will be examined in the context of these technology features. Presently, this technology offers MEMS feature sizes as small as 1 {micro}m, CMOS critical dimensions of 1.25 {micro}m, MEMS linear dimensions of 1,000 {micro}m, a single mechanical level of polysilicon, and a 100 {micro}m space between MEMS and CMOS. This is applicable to modern precision guided munitions.« less

Microelectromechanical System (MEMS) Device Being Developed for Active Cooling and Temperature Control

NASA Technical Reports Server (NTRS)

Beach, Duane E.

2003-01-01

High-capacity cooling options remain limited for many small-scale applications such as microelectronic components, miniature sensors, and microsystems. A microelectromechanical system (MEMS) using a Stirling thermodynamic cycle to provide cooling or heating directly to a thermally loaded surface is being developed at the NASA Glenn Research Center to meet this need. The device can be used strictly in the cooling mode or can be switched between cooling and heating modes in milliseconds for precise temperature control. Fabrication and assembly employ techniques routinely used in the semiconductor processing industry. Benefits of the MEMS cooler include scalability to fractions of a millimeter, modularity for increased capacity and staging to low temperatures, simple interfaces, limited failure modes, and minimal induced vibration. The MEMS cooler has potential applications across a broad range of industries such as the biomedical, computer, automotive, and aerospace industries. The basic capabilities it provides can be categorized into four key areas: 1) Extended environmental temperature range in harsh environments; 2) Lower operating temperatures for electronics and other components; 3) Precision spatial and temporal thermal control for temperature-sensitive devices; and 4) The enabling of microsystem devices that require active cooling and/or temperature control. The rapidly expanding capabilities of semiconductor processing in general, and microsystems packaging in particular, present a new opportunity to extend Stirling-cycle cooling to the MEMS domain. The comparatively high capacity and efficiency possible with a MEMS Stirling cooler provides a level of active cooling that is impossible at the microscale with current state-of-the-art techniques. The MEMS cooler technology builds on decades of research at Glenn on Stirling-cycle machines, and capitalizes on Glenn s emerging microsystems capabilities.

A fully wafer-level packaged RF MEMS switch with low actuation voltage using a piezoelectric actuator

NASA Astrophysics Data System (ADS)

Park, Jae-Hyoung; Lee, Hee-Chul; Park, Yong-Hee; Kim, Yong-Dae; Ji, Chang-Hyeon; Bu, Jonguk; Nam, Hyo-Jin

2006-11-01

In this paper, a fully wafer-level packaged RF MEMS switch has been demonstrated, which has low operation voltage, using a piezoelectric actuator. The piezoelectric actuator was designed to operate at low actuation voltage for application to advanced mobile handsets. The dc contact type RF switch was packaged using the wafer-level bonding process. The CPW transmission lines and piezoelectric actuators have been fabricated on separate wafers and assembled together by the wafer-level eutectic bonding process. A gold and tin composite was used for eutectic bonding at a low temperature of 300 °C. Via holes interconnecting the electrical contact pads through the wafer were filled completely with electroplated copper. The fully wafer-level packaged RF MEMS switch showed an insertion loss of 0.63 dB and an isolation of 26.4 dB at 5 GHz. The actuation voltage of the switch was 5 V. The resonant frequency of the piezoelectric actuator was 38.4 kHz and the spring constant of the actuator was calculated to be 9.6 N m-1. The size of the packaged SPST (single-pole single-through) switch was 1.2 mm × 1.2 mm including the packaging sealing rim. The effect of the proposed package structure on the RF performance was characterized with a device having CPW through lines and vertical feed lines excluding the RF switches. The measured packaging loss was 0.2 dB and the return loss was 33.6 dB at 5 GHz.

Sleep Estimates Using Microelectromechanical Systems (MEMS)

PubMed Central

te Lindert, Bart H. W.; Van Someren, Eus J. W.

2013-01-01

Study Objectives: Although currently more affordable than polysomnography, actigraphic sleep estimates have disadvantages. Brand-specific differences in data reduction impede pooling of data in large-scale cohorts and may not fully exploit movement information. Sleep estimate reliability might improve by advanced analyses of three-axial, linear accelerometry data sampled at a high rate, which is now feasible using microelectromechanical systems (MEMS). However, it might take some time before these analyses become available. To provide ongoing studies with backward compatibility while already switching from actigraphy to MEMS accelerometry, we designed and validated a method to transform accelerometry data into the traditional actigraphic movement counts, thus allowing for the use of validated algorithms to estimate sleep parameters. Design: Simultaneous actigraphy and MEMS-accelerometry recording. Setting: Home, unrestrained. Participants: Fifteen healthy adults (23-36 y, 10 males, 5 females). Interventions: None. Measurements: Actigraphic movement counts/15-sec and 50-Hz digitized MEMS-accelerometry. Analyses: Passing-Bablok regression optimized transformation of MEMS-accelerometry signals to movement counts. Kappa statistics calculated agreement between individual epochs scored as wake or sleep. Bland-Altman plots evaluated reliability of common sleep variables both between and within actigraphs and MEMS-accelerometers. Results: Agreement between epochs was almost perfect at the low, medium, and high threshold (kappa = 0.87 ± 0.05, 0.85 ± 0.06, and 0.83 ± 0.07). Sleep parameter agreement was better between two MEMS-accelerometers or a MEMS-accelerometer and an actigraph than between two actigraphs. Conclusions: The algorithm allows for continuity of outcome parameters in ongoing actigraphy studies that consider switching to MEMS-accelerometers. Its implementation makes backward compatibility feasible, while collecting raw data that, in time, could provide better sleep estimates and promote cross-study data pooling. Citation: te Lindert BHW; Van Someren EJW. Sleep estimates using microelectromechanical systems (MEMS). SLEEP 2013;36(5):781-789. PMID:23633761

A Capacitance-To-Digital Converter for MEMS Sensors for Smart Applications.

PubMed

Pérez Sanjurjo, Javier; Prefasi, Enrique; Buffa, Cesare; Gaggl, Richard

2017-06-07

The use of MEMS sensors has been increasing in recent years. To cover all the applications, many different readout circuits are needed. To reduce the cost and time to market, a generic capacitance-to-digital converter (CDC) seems to be the logical next step. This work presents a configurable CDC designed for capacitive MEMS sensors. The sensor is built with a bridge of MEMS, where some of them function with pressure. Then, the capacitive to digital conversion is realized using two steps. First, a switched-capacitor (SC) preamplifier is used to make the capacitive to voltage (C-V) conversion. Second, a self-oscillated noise-shaping integrating dual-slope (DS) converter is used to digitize this magnitude. The proposed converter uses time instead of amplitude resolution to generate a multibit digital output stream. In addition it performs noise shaping of the quantization error to reduce measurement time. This article shows the effectiveness of this method by measurements performed on a prototype, designed and fabricated using standard 0.13 µm CMOS technology. Experimental measurements show that the CDC achieves a resolution of 17 bits, with an effective area of 0.317 mm², which means a pressure resolution of 1 Pa, while consuming 146 µA from a 1.5 V power supply.

Improved response time of flexible microelectromechanical sensors employing eco-friendly nanomaterials.

PubMed

Fan, Shicheng; Dan, Li; Meng, Lingju; Zheng, Wei; Elias, Anastasia; Wang, Xihua

2017-11-09

Flexible force/pressure sensors are of interest for academia and industry and have applications in wearable technologies. Most of such sensors on the market or reported in journal publications are based on the operation mechanism of probing capacitance or resistance changes of the materials under pressure. Recently, we reported the microelectromechanical (MEM) sensors based on a different mechanism: mechanical switches. Multiples of such MEM sensors can be integrated to achieve the same function of regular force/pressure sensors while having the advantages of ease of fabrication and long-term stability in operation. Herein, we report the dramatically improved response time (more than one order of magnitude) of these MEM sensors by employing eco-friendly nanomaterials-cellulose nanocrystals. For instance, the incorporation of polydimethysiloxane filled with cellulose nanocrystals shortened the response time of MEM sensors from sub-seconds to several milliseconds, leading to the detection of both diastolic and systolic pressures in the radial arterial blood pressure measurement. Comprehensive mechanical and electrical characterization of the materials and the devices reveal that greatly enhanced storage modulus and loss modulus play key roles in this improved response time. The demonstrated fast-response flexible sensors enabled continuous monitoring of heart rate and complex cardiovascular signals using pressure sensors for future wearable sensing platforms.

A Capacitance-To-Digital Converter for MEMS Sensors for Smart Applications

PubMed Central

Pérez Sanjurjo, Javier; Prefasi, Enrique; Buffa, Cesare; Gaggl, Richard

2017-01-01

The use of MEMS sensors has been increasing in recent years. To cover all the applications, many different readout circuits are needed. To reduce the cost and time to market, a generic capacitance-to-digital converter (CDC) seems to be the logical next step. This work presents a configurable CDC designed for capacitive MEMS sensors. The sensor is built with a bridge of MEMS, where some of them function with pressure. Then, the capacitive to digital conversion is realized using two steps. First, a switched-capacitor (SC) preamplifier is used to make the capacitive to voltage (C-V) conversion. Second, a self-oscillated noise-shaping integrating dual-slope (DS) converter is used to digitize this magnitude. The proposed converter uses time instead of amplitude resolution to generate a multibit digital output stream. In addition it performs noise shaping of the quantization error to reduce measurement time. This article shows the effectiveness of this method by measurements performed on a prototype, designed and fabricated using standard 0.13 µm CMOS technology. Experimental measurements show that the CDC achieves a resolution of 17 bits, with an effective area of 0.317 mm2, which means a pressure resolution of 1 Pa, while consuming 146 µA from a 1.5 V power supply. PMID:28590425

Optical MEMS: boom, bust, and beyond

NASA Astrophysics Data System (ADS)

Payne, Richard S.

2005-01-01

Optical Telecommunications bandwidth, spurred by the growth of the internet, experienced unprecedented growth in the late 1990's. The creation of new enterprises was vast and the expansion of established component, system and services companies was also breathtaking. This period of speculative growth was followed in 2001-2004 by one of the most significant market crashes in history. While $20B of venture capital was invested in optical telecom in the last 10 years, the vast majority of that has been written off in the last 4. Countless start-ups inaugurated with great fanfare at the end of the 20th century were unceremoniously shut down at the start of the 21st century.(1) As in all speculative bubbles innovative technologies were born and were buried. Nonetheless, new capabilities emerge from the chaos and disruption; one such example is the advent of Optical MEMS (MOEMS). Its development was vigorously pursued in both academic and corporate laboratories during the boom and, in the author's view; MOEMS constitutes a powerful and versatile tool set that will be an invaluable residual of the last few years. In Telecommunications, MOEMS have been proven to be the technology of choice for many optical switching and wavelength management applications.(2) Variable Optical Attenuators (VOA), Wavelength Blockers (WB), Dynamic Gain Equalizers (DGE), and most recently Wavelength Selective Switches (WSS) are being used in the numerous recent network deployments. Moreover, agile networks of the future will have MOEMS at every node. This presentation will provide an overview of the history of MOEMS in Telecommunications, discuss their byproducts and project the future of the technology.

Optical MEMS: boom, bust and beyond

NASA Astrophysics Data System (ADS)

Ramani, Chandra Mouli

2005-10-01

Optical Telecommunications bandwidth, spurred by the growth of the internet, experienced unprecedented growth in the late 1990's. The creation of new enterprises was vast and the expansion of established component, system and services companies was also breathtaking. This period of speculative growth was followed in 2001-2004 by one of the most significant market crashes in history. While $20B of venture capital was invested in optical telecom in the last 10 years, the vast majority of that has been written off in the last four. Countless start-ups inaugurated with great fanfare at the end of the 20th century were unceremoniously shut down at the start of the 21st. (1) As in all speculative bubbles, innovative technologies were born and buried. Nonetheless, new capabilities emerge from the chaos and disruption; one such example is the advent of Optical MEMS (MOEMS). Its development was vigorously pursued in both academic and corporate laboratories during the boom and, in the author's view; MOEMS constitutes a powerful and versatile tool set that is an invaluable residual of the last few years. In Telecommunications, MOEMS has proven to be the technology of choice for many optical switching and wavelength management applications. (2) Variable Optical Attenuators (VOA), Wavelength Blockers (WB), Dynamic Gain Equalizers (DGE), and most recently Wavelength Selective Switches (WSS) are being used in the numerous recent network deployments. Moreover, agile networks of the future will have MOEMS at every node. This presentation will provide an overview of the history of MOEMS in Telecommunications, discuss its byproducts and project the future of the technology.

Overview of MEMS/NEMS technology development for space applications at NASA/JPL

NASA Astrophysics Data System (ADS)

George, Thomas

2003-04-01

This paper highlights the current technology development activities of the MEMS Technology Group at JPL. A diverse range of MEMS/NEMS technologies are under development, that are primarily applicable to NASA"s needs in the area of robotic planetary exploration. MEMS/NEMS technologies have obvious advantages for space applications, since they offer the promise of highly capable devices with ultra low mass, size and power consumption. However, the key challenge appears to be in finding efficient means to transition these technologies into "customer" applications. A brief description of this problem is presented along with the Group"s innovative approach to rapidly advance the maturity of technologies via insertion into space missions. Also described are some of the major capabilities of the MEMS Technology Group. A few important examples from among the broad classes of technologies being developed are discussed, these include the "Spider Web Bolometer", High-Performance Miniature Gyroscopes, an Electron Luminescence X-ray Spectrometer, a MEMS-based "Knudsen" Thermal Transpiration pump, MEMS Inchworm Actuators, and Nanowire-based Biological/Chemical Sensors.

Ka-Band, RF MEMS Switches on CMOS Grade Silicon with a Polyimide Interface Layer

NASA Technical Reports Server (NTRS)

Ponchak, George E.; Varaljay, Nicholas C.; Papapolymerou, John

2003-01-01

For the first time, RF MEMS switcbes on CMOS grade Si witb a polyimide interface layer are fabricated and characterized. At Ka-Band (36.6 GHz), an insertion loss of 0.52 dB and an isolation of 20 dB is obtained.

Charging and breakdown in amorphous dielectrics: Phenomenological modeling approach and applications

NASA Astrophysics Data System (ADS)

Palit, Sambit

Amorphous dielectrics of different thicknesses (nm to mm) are used in various applications. Low temperature processing/deposition of amorphous thin-film dielectrics often result in defect-states or electronic traps. These traps are responsible for increased leakage currents and bulk charge trapping in many associated applications. Additional defects may be generated during regular usage, leading to electrical breakdown. Increased leakage currents, charge trapping and defect generation/breakdown are important and pervasive reliability concerns in amorphous dielectrics. We first explore the issue of charge accumulation and leakage in amorphous dielectrics. Historically, charge transport in amorphous dielectrics has been presumed, depending on the dielectric thickness, to be either bulk dominated (Frenkel-Poole (FP) emission) or contact dominated (Fowler-Nordheim tunneling). We develop a comprehensive dielectric charging modeling framework which solves for the transient and steady state charge accumulation and leakage currents in an amorphous dielectric, and show that for intermediate thickness dielectrics, the conventional assumption of FP dominated current transport is incorrect, and may lead to false extraction of dielectric parameters. We propose an improved dielectric characterization methodology based on an analytical approximation of our model. Coupled with ab-initio computed defect levels, the dielectric charging model explains measured leakage currents more accurately with lesser empiricism. We study RF-MEMS capacitive switches as one of the target applications of intermediate thickness amorphous dielectrics. To achieve faster analysis and design of RF-MEMS switches in particular, and electro-mechanical actuators in general, we propose a set of fundamental scaling relationships which are independent of specific physical dimensions and material properties; the scaling relationships provide an intrinsic classification of all electro-mechanical actuators. However, RF-MEMS capacitive switches are plagued by the reliability issue of temporal shifts of actuation voltages due to dielectric charge accumulation, often resulting in failure due to membrane stiction. Using the dielectric charging model, we show that in spite of unpredictable roughness of deposited dielectrics, there are predictable shifts in actuation voltages due to dielectric charging in RF-MEMS switches. We also propose a novel non-obtrusive, non-contact, fully electronic resonance based technique to characterize charging driven actuation shifts in RF-MEMS switches which overcomes limitations in conventionally used methods. Finally, we look into the issue of defect generation and breakdown in thick polymer dielectrics. Polymer materials often face premature electrical breakdown due to high electric fields and frequencies, and exposure to ambient humidity conditions. Using a field-driven correlated defect generation model, coupled with a model for temperature rise due to dielectric heating at AC stresses, we explain measured trends in time-to-breakdown and breakdown electric fields in polymer materials. Using dielectric heating we are able to explain the observed lifetime and dielectric strength reduction with increasing dielectric thicknesses. Performing lifetime measurements after exposure to controlled humidity conditions, we find that moisture ingress into a polymer material reduces activation barriers for chain breakage and increases dielectric heating. Overall, this thesis develops a comprehensive framework of dielectric charging, leakage and degradation of insulators of different thicknesses that have broad applications in multiple technologies.

The Fundamentals of Using the Digital Micromirror Device (DMD(TM)) for Projection Display

NASA Technical Reports Server (NTRS)

Yoder, Lars A.

1995-01-01

Developed by Texas Instruments (TI) the digital micromirror device (DMD(tm)) is a quickly emerging and highly useful micro-electro-mechanical structures (MEMS) device. Using standard semiconductor fabrication technology, the DMD's simplicity in concept and design will provide advantageous solutions for many different applications. At the rudimentary level, the DMD is a precision, semiconductor light switch. In the initial commercial development of DMD technology, TI has concentrated on projection display and hardcopy. This paper will focus on how the DMD is used for projection display. Other application areas are being explored and evaluated to find appropriate and beneficial uses for the DMD.

Standard semiconductor packaging for high-reliability low-cost MEMS applications

NASA Astrophysics Data System (ADS)

Harney, Kieran P.

2005-01-01

Microelectronic packaging technology has evolved over the years in response to the needs of IC technology. The fundamental purpose of the package is to provide protection for the silicon chip and to provide electrical connection to the circuit board. Major change has been witnessed in packaging and today wafer level packaging technology has further revolutionized the industry. MEMS (Micro Electro Mechanical Systems) technology has created new challenges for packaging that do not exist in standard ICs. However, the fundamental objective of MEMS packaging is the same as traditional ICs, the low cost and reliable presentation of the MEMS chip to the next level interconnect. Inertial MEMS is one of the best examples of the successful commercialization of MEMS technology. The adoption of MEMS accelerometers for automotive airbag applications has created a high volume market that demands the highest reliability at low cost. The suppliers to these markets have responded by exploiting standard semiconductor packaging infrastructures. However, there are special packaging needs for MEMS that cannot be ignored. New applications for inertial MEMS devices are emerging in the consumer space that adds the imperative of small size to the need for reliability and low cost. These trends are not unique to MEMS accelerometers. For any MEMS technology to be successful the packaging must provide the basic reliability and interconnection functions, adding the least possible cost to the product. This paper will discuss the evolution of MEMS packaging in the accelerometer industry and identify the main issues that needed to be addressed to enable the successful commercialization of the technology in the automotive and consumer markets.

Standard semiconductor packaging for high-reliability low-cost MEMS applications

NASA Astrophysics Data System (ADS)

Harney, Kieran P.

2004-12-01

Microelectronic packaging technology has evolved over the years in response to the needs of IC technology. The fundamental purpose of the package is to provide protection for the silicon chip and to provide electrical connection to the circuit board. Major change has been witnessed in packaging and today wafer level packaging technology has further revolutionized the industry. MEMS (Micro Electro Mechanical Systems) technology has created new challenges for packaging that do not exist in standard ICs. However, the fundamental objective of MEMS packaging is the same as traditional ICs, the low cost and reliable presentation of the MEMS chip to the next level interconnect. Inertial MEMS is one of the best examples of the successful commercialization of MEMS technology. The adoption of MEMS accelerometers for automotive airbag applications has created a high volume market that demands the highest reliability at low cost. The suppliers to these markets have responded by exploiting standard semiconductor packaging infrastructures. However, there are special packaging needs for MEMS that cannot be ignored. New applications for inertial MEMS devices are emerging in the consumer space that adds the imperative of small size to the need for reliability and low cost. These trends are not unique to MEMS accelerometers. For any MEMS technology to be successful the packaging must provide the basic reliability and interconnection functions, adding the least possible cost to the product. This paper will discuss the evolution of MEMS packaging in the accelerometer industry and identify the main issues that needed to be addressed to enable the successful commercialization of the technology in the automotive and consumer markets.

Vision for Micro Technology Space Missions. Chapter 2

NASA Technical Reports Server (NTRS)

Dennehy, Neil

2005-01-01

It is exciting to contemplate the various space mission applications that Micro Electro Mechanical Systems (MEMS) technology could enable in the next 10-20 years. The primary objective of this chapter is to both stimulate ideas for MEMS technology infusion on future NASA space missions and to spur adoption of the MEMS technology in the minds of mission designers. This chapter is also intended to inform non-space oriented MEMS technologists, researchers and decision makers about the rich potential application set that future NASA Science and Exploration missions will provide. The motivation for this chapter is therefore to lead the reader down a path to identify and it is exciting to contemplate the various space mission applications that Micro Electro Mechanical Systems (MEMS) technology could enable in the next 10-20 years. The primary objective of this chapter is to both stimulate ideas for MEMS technology infusion on future NASA space missions and to spur adoption of the MEMS technology in the minds of mission designers. This chapter is also intended to inform non-space oriented MEMS technologists, researchers and decision makers about the rich potential application set that future NASA Science and Exploration missions will provide. The motivation for this chapter is therefore to lead the reader down a path to identify and consider potential long-term, perhaps disruptive or revolutionary, impacts that MEMS technology may have for future civilian space applications. A general discussion of the potential for MEMS in space applications is followed by a brief showcasing of a few selected examples of recent MEMS technology developments for future space missions. Using these recent developments as a point of departure, a vision is then presented of several areas where MEMS technology might eventually be exploited in future Science and Exploration mission applications. Lastly, as a stimulus for future research and development, this chapter summarizes a set of barriers to progress, design challenges and key issues that must be overcome in order for the community to move on, from the current nascent phase of developing and infusing MEMS technology into space missions, in order to achieve its full future potential.

Non-Destructive Damping Measurement for Wafer-Level Packaged Microelectromechanical System (MEMS) Acceleration Switches

DTIC Science & Technology

2014-09-01

Micromechanics and Microengineering . 2005;15:176–184. 10. Mohite SS, Kesari H, Sonti VR, Pratap R. Analytical solutions for the stiffness and damping...coefficients of squeeze films in MEMS devices with perforated back plates. Journal of Micromechanics and Microengineering . 2005;15:2083–2092. 11. Younis MI

Micro/nano electro mechanical systems for practical applications

NASA Astrophysics Data System (ADS)

Esashi, Masayoshi

2009-09-01

Silicon MEMS as electrostatically levitated rotational gyroscope, 2D optical scanner and wafer level packaged devices as integrated capacitive pressure sensor and MEMS switch are described. MEMS which use non-silicon materials as diamond, PZT, conductive polymer, CNT (carbon nano tube), LTCC with electrical feedthrough, SiC (silicon carbide) and LiNbO3 for multi-probe data storage, multi-column electron beam lithography system, probe card for wafer-level burn-in test, mould for glass press moulding and SAW wireless passive sensor respectively are also described.

Mechano-micro/nano systems

NASA Astrophysics Data System (ADS)

Horie, Mikio

2004-10-01

In recent years, the researches about Micro/Nano Systems are down actively in the bio-medical research fields, DNA research fields, chemical analysis systems fields, etc. In the results, a new materials and new functions in the systems are developed. In this invited paper, Mechano-Micro/Nano Systems, especially, motion systems are introduced. First, the research activities concerning the Mechano-Micro/Nano Systems in the world(MST2003, MEMS2003 and MEMS2004) and in Japan(Researech Projects on Nanotechnology and Materials in Ministry of Education, Culture, Sports, Science and Technology) are shown. Secondary, my research activities are introduced. As my research activities, (1) a comb-drive static actuator for the motion convert mechanisms, (2) a micro-nano fabrication method by use of FAB(Fast Atom Beam) machines, (3) a micro optical mirror manipulator for inputs-outputs optical switches, (4) a miniature pantograph mechanism with large-deflective hinges and links made of plastics are discussed and their performances are explained.

Temperature-dependent mechanical behavior of silicon dioxide, gold and gold-vanadium thin films for VLSI integrated circuits and MicroElectroMechanical systems (MEMs)

NASA Astrophysics Data System (ADS)

Lin, Ming-Tzer

The Semiconductor Industry has grown rapidly in the last twenty years. The national technology roadmap for semiconductors plans for developing the complexity and packing density of semiconductor devices into the next decade, allowing ever smaller and more densely packed structures to be fabricated. Recently, MEMS (Micro-Electro-Mechanical Systems) have become important in modern technology. The goal of MEMs is to integrate many types of miniature devices on a single chip, creating a new micro-world. The oxidation of silicon is one of the most important processes in semiconductor technology. Producing high-quality IC's and MEMS devices requires an understanding of the basic oxidation mechanism. In addition, for the reliability of IC's and MEMS devices, the mechanical properties of the oxide play a critical role. There has been an apparent convergence of opinion on the relevant mechanism leading to the "standard computational model" for stress effects on silicon oxidation. This model has recently become suspect. Most of the reasonably direct experimental data on the flow properties of SiO 2 thin film do not support a stress-dependent viscosity of the sort envisioned by the model. Gold and gold vanadium alloys are used in electrical interconnections and in radio frequency switch contacts for the semiconductor industry, MEMs sensors for the aerospace industry and also in brain probes by the bioelectronics mechanical industry. Despite the strong potential usage of gold and gold vanadium thin films at the small scale, very little is known about their mechanical properties. Our goal was to experimentally investigate stress and its influence on SiO2 thin films and the mechanical properties of gold and gold vanadium thin films at room temperature and at elevated temperature of different vanadium concentration. We found that the application of relatively small amounts of bending to an oxidizing silicon substrate leads to significant decreases in oxide thickness in the ultrathin oxide regime. Both tensile and compressive bending retard oxide growth, although compressive bending results in somewhat thinner oxides than does tensile bending. We also determined the modulus of gold and gold vanadium, and discovered that there is some evidence for a vanadium concentration dependence of the mechanical properties.

Converting MEMS technology into profits

NASA Astrophysics Data System (ADS)

Bryzek, Janusz

1998-08-01

This paper discusses issues related to transitioning a company from the advanced technology development phase (with a particular focus on MEMS) to a profitable business, with emphasis on start-up companies. It includes several case studies from (primarily) NovaSensor MEMS development history. These case studies illustrate strategic problems with which advanced MEMS technology developers have to be concerned. Conclusions from these case studies could be used as checkpoints for future MEMS developers to increase probability of profitable operations. The objective for this paper is to share the author's experience from multiple MEMS start-ups to accelerate development of the MEMS market by focusing state- of-the-art technologists on marketing issues.

Demonstration of a linear optical true-time delay device by use of a microelectromechanical mirror array.

PubMed

Rader, Amber; Anderson, Betty Lise

2003-03-10

We present the design and proof-of-concept demonstration of an optical device capable of producing true-time delay(s) (TTD)(s) for phased array antennas. This TTD device uses a free-space approach consisting of a single microelectromechanical systems (MEMS) mirror array in a multiple reflection spherical mirror configuration based on the White cell. Divergence is avoided by periodic refocusing by the mirrors. By using the MEMS mirror to switch between paths of different lengths, time delays are generated. Six different delays in 1-ns increments were demonstrated by using the Texas Instruments Digital Micromirror Device as the switching element. Losses of 1.6 to 5.2 dB per bounce and crosstalk of -27 dB were also measured, both resulting primarily from diffraction from holes in each pixel and the inter-pixel gaps of the MEMS.

Electrothermally actuated tip-tilt-piston micromirror with integrated varifocal capability.

PubMed

Morrison, Jessica; Imboden, Matthias; Little, Thomas D C; Bishop, D J

2015-04-06

MEMS micromirrors have proven to be very important optical devices with applications ranging from steerable mirrors for switches and cross-connects to spatial light modulators for correcting optical distortions. Usually beam steering and focusing are done with different MEMS devices and tilt angles in excess of 10 degrees are seldom obtained. Here we describe a single MEMS device that combines tip/tilt, piston mode and varifocal capability into a single, low cost device with very large tilt angles. Our device consists of a 400 micron diameter mirror driven with thermal bimorphs. We have demonstrated deflection angles of ± 40 degrees along both axes, a tunable focal length which varies between -0.48 mm to + 20.5 mm and a piston mode range of 300 microns - four separately controllable degrees of freedom in a single device. Potential applications range from smart lighting to optical switches and devices for telecom systems.

Recent progress in MEMS technology development for military applications

NASA Astrophysics Data System (ADS)

Ruffin, Paul B.; Burgett, Sherrie J.

2001-08-01

The recent progress of ongoing efforts at the Army Aviation and Missile Command (AMCOM) to develop microelectromechanical systems (MEMS) technology for military applications is discussed in this paper. The current maturity level of low cost, low power, micro devices in industry, which range from simple temperature and pressure sensors to accelerometers in airbags, provides a viable foundation for the development of rugged MEMS devices for dual-use applications. Early MEMS technology development efforts at AMCOM emphasized inertial MEMS sensors. An Army Science and Technology Objective (STO) project was initiated to develop low cost inertial components with moderate angular rate sensor resolution for measuring pitch and yaw of missile attitude and rotational roll rate. Leveraging the Defense Advanced Research Projects Agency and other Government agencies has resulted in the development of breadboard inertial MEMS devices with improved robustness. During the past two years, MEMS research at AMCOM has been expanded to include environmental MEMS sensors for missile health monitoring, RF-MEMS, optical MEMS devices for beam steering, and micro-optic 'benches' for opto-electronics miniaturization. Additionally, MEMS packaging and integration issues have come into focus and are being addressed. Selected ongoing research efforts in these areas are presented, and some horizon MEMS sensors requirements for Army and law enforcement are presented for consideration.

Optical MEMS: past, present and future

NASA Astrophysics Data System (ADS)

Ramani, Chandra Mouli

2005-09-01

Spurred by the growth of the internet, Optical Telecommunications bandwidth, experienced unprecedented growth during late 1990's. During this time of great economic expansion, the creation of new enterprises was vast and the expansion of established component, system and services companies was breathtaking. Unfortunately, this positive economic state was short-lived. This period was followed in 2001-2004 by one of the most significant market crashes in history. During those 10 years of economic growth, about $20B in venture capital was invested in the optical telecom industry, most of this investment was lost in recent years. Many start-up industries which experienced unprecedented growth at the end of the 20th century were lost at the start of the 21st. (1) During this time many, innovative technologies were born and buried. However, many new capabilities emerged from this period of unrest; one such example is the advent of Optical MEMS (MOEMS). Many academics and corporate laboratories pursued the development of MOEMS during the economic boom and, in the author's view; MOEMS surfaced as a powerful and versatile tool set that has proved invaluable and in the last few years during economic downturn, stood the test of time. In the Telecommunications industry, for optical switching and wavelength management applications MOEMS has proven to be the technology of choice. (2) Variable Optical Attenuators (VOA), Wavelength Blockers (WB), Dynamic Gain Equalizers (DGE), and most recently Wavelength Selective Switches (WSS) are being used in the numerous recent network deployments. Moreover, agile networks of the future will have MOEMS at every node. This presentation will provide an overview of the history of MOEMS in Telecommunications, discuss its byproducts and offer a window into the future of the technology.

A Novel Offset Cancellation Based on Parasitic-Insensitive Switched-Capacitor Sensing Circuit for the Out-of-Plane Single-Gimbaled Decoupled CMOS-MEMS Gyroscope

PubMed Central

Chang, Ming-Hui; Huang, Han-Pang

2013-01-01

This paper presents a novel parasitic-insensitive switched-capacitor (PISC) sensing circuit design in order to obtain high sensitivity and ultra linearity and reduce the parasitic effect for the out-of-plane single-gimbaled decoupled CMOS-MEMS gyroscope (SGDG). According to the simulation results, the proposed PISC circuit has better sensitivity and high linearity in a wide dynamic range. Experimental results also show a better performance. In addition, the PISC circuit can use signal processing to cancel the offset and noise. Thus, this circuit is very suitable for gyroscope measurement. PMID:23493122

Microelectromechanical Systems and Nephrology: The Next Frontier in Renal Replacement Technology

PubMed Central

Kim, Steven; Roy, Shuvo

2013-01-01

Microelectromechanical systems (MEMS) is playing a prominent role in the development of many new and innovative biomedical devices, but remains a relatively underutilized technology in nephrology. The future landscape of clinical medicine and research will only see further expansion of MEMS based technologies in device designs and applications. The enthusiasm stems from the ability to create small-scale device features with high precision in a cost effective manner. MEMS also offers the possibility to integrate multiple components into a single device. The adoption of MEMS has the potential to revolutionize how nephrologists manage kidney disease by improving the delivery of renal replacement therapies and enhancing the monitoring of physiologic parameters. To introduce nephrologists to MEMS, this review will first define relevant terms and describe the basic processes used to fabricate MEMS devices. Next, a survey of MEMS devices being developed for various biomedical applications will be illustrated with current examples. Finally, MEMS technology specific to nephrology will be highlighted and future applications will be examined. The adoption of MEMS offers novel avenues to improve the care of kidney disease patients and assist nephrologists in clinical practice. This review will serve as an introduction for nephrologists to the exciting world of MEMS. PMID:24206604

Science& Technology Review October 2003

DOE Office of Scientific and Technical Information (OSTI.GOV)

McMahon, D H

2003-10-01

The October 2003 issue of Science & Technology Review consists of the following articles: (1) Award-Winning Technologies from Collaborative Efforts--Commentary by Hal Graboske; (2) BASIS Counters Airborne Bioterrorism--The Biological Aerosol Sentry and Information System is the first integrated biodefense system; (3) In the Chips for the Coming Decade--A new system is the first full-field lithography tool for use at extreme ultraviolet wavelengths; (4) Smoothing the Way to Print the Next Generation of Computer Chips--With ion-beam thin-film planarization, the reticles and projection optics made for extreme ultraviolet lithography are nearly defect-free; (5) Eyes Can See Clearly Now--The MEMS-based adaptive optics phoroptermore » improves the process of measuring and correcting eyesight aberrations; (6) This Switch Takes the Heat--A thermally compensated Q-switch reduces the light leakage on high-average-power lasers; (7) Laser Process Forms Thick, Curved Metal Parts--A new process shapes parts to exact specifications, improving their resistance to fatigue and corrosion cracking; and (8) Characterizing Tiny Objects without Damaging Them--Livermore researchers are developing nondestructive techniques to probe the Lilliputian world of mesoscale objects.« less

A 2D Rods-in-Air Square-Lattice Photonic Crystal Optical Switch

DTIC Science & Technology

2009-03-01

4] Tao Chu, Hirohito Yamada, Satomi Ishida, Yasuhiko Arakawa, Thermooptic switch based on photonic-crystal line-defect waveguides, IEEE Photon...Ishida, Yasuhiko Arakawa, Hiroyuki Fujita, Hiroshi Toshiyoshi, Design and fabrication on MEMS optical mod- ulators integrated with Phc waveguide, in

Influence of adhesive rough surface contact on microswitches

NASA Astrophysics Data System (ADS)

Wu, Ling; Rochus, V.; Noels, L.; Golinval, J. C.

2009-12-01

Stiction is a major failure mode in microelectromechanical systems (MEMS). Undesirable stiction, which results from contact between surfaces, threatens the reliability of MEMS severely as it breaks the actuation function of MEMS switches, for example. Although it may be possible to avoid stiction by increasing restoring forces using high spring constants, it follows that the actuation voltage has also to be increased significantly, which reduces the efficiency. In our research, an electrostatic-structural analysis is performed to estimate the proper design range of the equivalent spring constant, which is the main factor of restoring force in MEMS switches. The upper limit of equivalent spring constant is evaluated based on the initial gap width, the dielectric thickness, and the expected actuation voltage. The lower limit is assessed on the value of adhesive forces between the two contacting rough surfaces. The MEMS devices studied here are assumed to work in a dry environment. In these operating conditions only the van der Waals forces have to be considered for adhesion. A statistical model is used to simulate the rough surface, and the Maugis's model is combined with Kim's expansion to calculate adhesive forces. In the resulting model, the critical value of the spring stiffness depends on the material and surface properties, such as the elastic modulus, surface energy, and surface roughness. The aim of this research is to propose simple rules for design purposes.

Liquid Metal Droplet and Micro Corrugated Diaphragm RF-MEMS for reconfigurable RF filters

NASA Astrophysics Data System (ADS)

Irshad, Wasim

Widely Tunable RF Filters that are small, cost-effective and offer ultra low power consumption are extremely desirable. Indeed, such filters would allow drastic simplification of RF front-ends in countless applications from cell phones to satellites in space by replacing switched-array of static acoustic filters and YIG filters respectively. Switched array of acoustic filters are de facto means of channel selection in mobile applications such as cell phones. SAW and BAW filters satisfy most criteria needed by mobile applications such as low cost, size and power consumption. However, the trade-off is a significant loss of 3-4 dB in modern cell phone RF front-end. This leads to need for power-hungry amplifiers and short battery life. It is a necessary trade-off since there are no better alternatives. These devices are in mm scale and consume mW. YIG filters dominate applications where size or power is not a constraint but demand excellent RF performance like low loss and high tuning ratio. These devices are measured in inches and require several watts to operate. Clearly, a tunable RF filter technology that would combine the cost, size and power consumption benefits of acoustic filters with excellent RF performance of YIG filters would be extremely desirable and imminently useful. The objective of this dissertation is to develop such a technology based upon RF-MEMS Evanescent-mode cavity filter. Two highly novel RF-MEMS devices have been developed over the course of this PhD to address the unique MEMS needs of this technology. The first part of the dissertation is dedicated to introducing the fundamental concepts of tunable cavity resonators and filters. This includes the physics behind it, key performance metrics and what they depend on and requirements of the MEMS tuners. Initial gap control and MEMS attachment method are identified as potential hurdles towards achieving very high RF performance. Simple and elegant solutions to both these issues are discussed in detail and have proved pivotal to this work. The second part of the dissertation focuses on the Liquid Metal Droplet RF-MEMS. A novel tunable RF MEMS resonator that is based upon electrostatic control over the morphology of a liquid metal droplet (LMD) is conceived. We demonstrate an LMD evanescent-mode cavity resonator that simultaneously achieves wide analog tuning from 12 to 18 GHz with a measured quality factor of 1400-1840. A droplet of 250-mum diameter is utilized and the applied bias is limited to 100 V. This device operates on a principle called Electro-Wetting On Dielectric (EWOD). The liquid metal employed is a non-toxic eutectic alloy of Gallium, Indium and Tin known as Galinstan. This device also exploits interfacial surface energy and viscous body forces that dominate at nanoliter scale. We then apply our Liquid Metal Droplet (LMD) RF-MEMS architecture to demonstrate a continuously tunable electrostatic Ku-Band Filter. A 2-pole bandpass filter with measured insertion loss of less than 0.4dB and 3dB FBW of 3.4% is achieved using a Galinstan droplet of 250mum diameter and bias limited to 100V. We demonstrate that the LMD is insensitive to gravity by performing inversion and tilt experiments. In addition, we study its thermal tolerance by subjecting the LMD up to 150° C. The third part of the dissertation is dedicated to the Micro-Corrugated Diaphragm (MCD) RF-MEMS. We present an evanescent-mode cavity bandpass filter with state-of-the-art RF performance metrics like 4:1 tuning ratio from 5 to 20 GHz with less than 2dB insertion loss and 2-6% 3dB bandwidth. Micro-Corrugated Diaphragm (MCD) is a novel electrostatic MEMS design specifically engineered to provide large-scale analog deflections necessary for such continuous and wide tunable filtering with very high quality factor. We demonstrate a 1.25mm radius and 2mum thick Gold MCD which provides 30mum total deflection with nearly 60% analog range. We also present a detailed and systematic MCD design methodology for relevant applications. To further demonstrate MCD versatility, we implement a bandstop MCD filter that cascades nine separate resonators to achieve a 6-24 GHz continuous tuning. The disseration concludes with a Galinstan Magnetohydrodynamic (MHD) micropump and summary of my doctoral work. Although presented at the very end of this dissertation, the MHD micropump was indeed the very starting point for all my doctoral research efforts. The invaluable lessons learned here paved the way for development of both LMD and MCD RF-MEMS.

Evaluation of the optical switching characteristics of erbium-doped fibres for the development of a fibre Bragg grating sensor interrogator

NASA Astrophysics Data System (ADS)

Rigas, Evangelos; Correia, R.; Stathopoulos, N. A.; Savaidis, S. P.; James, S. W.; Bhattacharyya, D.; Kirby, P. B.; Tatam, R. P.

2014-05-01

A polling topology that employs optical switching based on the properties of erbium-doped fibres (EDFs) is used to interrogate an array of FBGs. The properties of the EDF are investigated in its pumped and un-pumped states and the EDFs' switching properties are evaluated by comparing them with a high performance electronically controlled MEM optical switch. Potential advantages of the proposed technique are discussed.

Simple Fall Criteria for MEMS Sensors: Data Analysis and Sensor Concept

PubMed Central

Ibrahim, Alwathiqbellah; Younis, Mohammad I.

2014-01-01

This paper presents a new and simple fall detection concept based on detailed experimental data of human falling and the activities of daily living (ADLs). Establishing appropriate fall algorithms compatible with MEMS sensors requires detailed data on falls and ADLs that indicate clearly the variations of the kinematics at the possible sensor node location on the human body, such as hip, head, and chest. Currently, there is a lack of data on the exact direction and magnitude of each acceleration component associated with these node locations. This is crucial for MEMS structures, which have inertia elements very close to the substrate and are capacitively biased, and hence, are very sensitive to the direction of motion whether it is toward or away from the substrate. This work presents detailed data of the acceleration components on various locations on the human body during various kinds of falls and ADLs. A two-degree-of-freedom model is used to help interpret the experimental data. An algorithm for fall detection based on MEMS switches is then established. A new sensing concept based on the algorithm is proposed. The concept is based on employing several inertia sensors, which are triggered simultaneously, as electrical switches connected in series, upon receiving a true fall signal. In the case of everyday life activities, some or no switches will be triggered resulting in an open circuit configuration, thereby preventing false positive. Lumped-parameter model is presented for the device and preliminary simulation results are presented illustrating the new device concept. PMID:25006997

Application of Micro-Electro-Mechanical Sensors Contactless NDT of Concrete Structures.

PubMed

Ham, Suyun; Popovics, John S

2015-04-17

The utility of micro-electro-mechanical sensors (MEMS) for application in air-coupled (contactless or noncontact) sensing to concrete nondestructive testing (NDT) is studied in this paper. The fundamental operation and characteristics of MEMS are first described. Then application of MEMS sensors toward established concrete test methods, including vibration resonance, impact-echo, ultrasonic surface wave, and multi-channel analysis of surface waves (MASW), is demonstrated. In each test application, the performance of MEMS is compared with conventional contactless and contact sensing technology. Favorable performance of the MEMS sensors demonstrates the potential of the technology for applied contactless NDT efforts. To illustrate the utility of air-coupled MEMS sensors for concrete NDT, as compared with conventional sensor technology.

MEMS in Space Systems

NASA Technical Reports Server (NTRS)

Lyke, J. C.; Michalicek, M. A.; Singaraju, B. K.

1995-01-01

Micro-electro-mechanical systems (MEMS) provide an emerging technology that has the potential for revolutionizing the way space systems are designed, assembled, and tested. The high launch costs of current space systems are a major determining factor in the amount of functionality that can be integrated in a typical space system. MEMS devices have the ability to increase the functionality of selected satellite subsystems while simultaneously decreasing spacecraft weight. The Air Force Phillips Laboratory (PL) is supporting the development of a variety of MEMS related technologies as one of several methods to reduce the weight of space systems and increase their performance. MEMS research is a natural extension of PL research objectives in micro-electronics and advanced packaging. Examples of applications that are under research include on-chip micro-coolers, micro-gyroscopes, vibration sensors, and three-dimensional packaging technologies to integrate electronics with MEMS devices. The first on-orbit space flight demonstration of these and other technologies is scheduled for next year.

Micromechanical Switches on GaAs for Microwave Applications

NASA Technical Reports Server (NTRS)

Randall, John N.; Goldsmith, Chuck; Denniston, David; Lin, Tsen-Hwang

1995-01-01

In this presentation, we describe the fabrication of micro-electro-mechanical system (MEMS) devices, in particular, of low-frequency multi-element electrical switches using SiO2 cantilevers. The switches discussed are related to micromechanical membrane structures used to perform switching of optical signals on silicon substrates. These switches use a thin metal membrane which is actuated by an electrostatic potential, causing the switch to make or break contact. The advantages include: superior isolation, high power handling capabilities, high radiation hardening, very low power operations, and the ability to integrate onto GaAs monolithic microwave integrated circuit (MMIC) chips.

A novel MEMS inertial switch with a reinforcing rib structure and electrostatic power assist to prolong the contact time

NASA Astrophysics Data System (ADS)

Li, Jian; Wang, Yan; Yang, Zhuoqing; Ding, Guifu; Zhao, Xiaolin; Wang, Hong

2018-03-01

The MEMS inertial switch is widely used in various industries owing to its advantage of small size, high integration, low power consumption and low costs, especially in the timing of Internet of things, such as toys, handheld devices, accessories and vibration testing. This paper provided a novel inertial switch with a reinforcing rib structure and electrostatic power assist. The designed inertial switch can reduce the complexity of the post-processing circuit and broaden its application prospect. The continuous electrostatic force can extend the contact time of the designed inertia switch before the leakage of electricity ends. The moving electrode with a reinforcing rib structure can effectively restrain the bending of the lower surface of moving electrode caused by residual stress. The array-type fixed electrode can ensure stable contact between the electrodes when the device is sensitive to external shocks. The dynamic displacement-time curve can be simulated by the COMSOL finite element simulation software. The laminated plating process is used to produce the designed inertial switch and the drop hammer acceleration monitoring system is used to test the fabricated device. The results indicate that, compared with the traditional design, the bouncing phenomenon can be prevented and extend the contact time to 336μs.

A flexible telecom satellite repeater based on microwave photonic technologies

NASA Astrophysics Data System (ADS)

Sotom, Michel; Benazet, Benoît; Maignan, Michel

2017-11-01

Future telecom satellite based on geo-stationary Earth orbit (GEO) will require advanced payloads in Kaband so as to receive, route and re-transmit hundreds of microwave channels over multiple antenna beams. We report on the proof-of-concept demonstration of a analogue repeater making use of microwave photonic technologies for supporting broadband, transparent, and flexible cross-connectivity. It has microwave input and output sections, and features a photonic core for LO distribution, frequency down-conversion, and cross-connection of RF channels. With benefits such as transparency to RF frequency, infinite RF isolation, mass and volume savings, such a microwave photonic cross-connect would compare favourably with microwave implementations, and based on optical MEMS switches could grow up to large port counts.

Microelectromechanical Systems Actuator Based Reconfigurable Printed Antenna

NASA Technical Reports Server (NTRS)

Simons, Rainee N. (Inventor)

2005-01-01

A polarization reconfigurable patch antenna is disclosed. The antenna includes a feed element, a patch antenna element electrically connected to the feed element, and at least one microelectromechanical systems (MEMS) actuator, with a partial connection to the patch antenna element along an edge of the patch antenna element. The polarization of the antenna can be switched between circular polarization and linear polarization through action of the at least one MEMS actuator.

MEMS testing and applications in automotive and aerospace industries

NASA Astrophysics Data System (ADS)

Ma, Zhichun; Chen, Xuyuan

2009-05-01

MEMS technology combines micromachining and integrated circuit fabrication technologies to produce highly reliable MEMS transducers. This paper presents an overview of MEMS transducers applications, particularly in automotive and aerospace industries, which includes inertia sensors for safety, navigation, and guidance control, thermal anemometer for temperature and heat-flux sensors in engine applications, MEMS atomizers for fuel injection, and micromachined actuators for flow control applications. Design examples for the devices in above mentioned applications are also presented and test results are given.

A capacitive CMOS-MEMS sensor designed by multi-physics simulation for integrated CMOS-MEMS technology

NASA Astrophysics Data System (ADS)

Konishi, Toshifumi; Yamane, Daisuke; Matsushima, Takaaki; Masu, Kazuya; Machida, Katsuyuki; Toshiyoshi, Hiroshi

2014-01-01

This paper reports the design and evaluation results of a capacitive CMOS-MEMS sensor that consists of the proposed sensor circuit and a capacitive MEMS device implemented on the circuit. To design a capacitive CMOS-MEMS sensor, a multi-physics simulation of the electromechanical behavior of both the MEMS structure and the sensing LSI was carried out simultaneously. In order to verify the validity of the design, we applied the capacitive CMOS-MEMS sensor to a MEMS accelerometer implemented by the post-CMOS process onto a 0.35-µm CMOS circuit. The experimental results of the CMOS-MEMS accelerometer exhibited good agreement with the simulation results within the input acceleration range between 0.5 and 6 G (1 G = 9.8 m/s2), corresponding to the output voltages between 908.6 and 915.4 mV, respectively. Therefore, we have confirmed that our capacitive CMOS-MEMS sensor and the multi-physics simulation will be beneficial method to realize integrated CMOS-MEMS technology.

Progress and opportunities in high-voltage microactuator powering technology towards one-chip MEMS

NASA Astrophysics Data System (ADS)

Mita, Yoshio; Hirakawa, Atsushi; Stefanelli, Bruno; Mori, Isao; Okamoto, Yuki; Morishita, Satoshi; Kubota, Masanori; Lebrasseur, Eric; Kaiser, Andreas

2018-04-01

In this paper, we address issues and solutions for micro-electro-mechanical-systems (MEMS) powering through semiconductor devices towards one-chip MEMS, especially those with microactuators that require high voltage (HV, which is more than 10 V, and is often over 100 V) for operation. We experimentally and theoretically demonstrated that the main reason why MEMS actuators need such HV is the tradeoff between resonant frequency and displacement amplitude. Indeed, the product of frequency and displacement is constant regardless of the MEMS design, but proportional to the input energy, which is the square of applied voltage in an electrostatic actuator. A comprehensive study on the principles of HV device technology and associated circuit technologies, especially voltage shifter circuits, was conducted. From the viewpoint of on-chip energy source, series-connected HV photovoltaic cells have been discussed. Isolation and electrical connection methods were identified to be key enabling technologies. Towards future rapid development of such autonomous devices, a technology to convert standard 5 V CMOS devices into HV circuits using SOI substrate and a MEMS postprocess is presented. HV breakdown experiments demonstrated this technology can hold over 700 to 1000 V, depending on the layout.

Design and Optimization of a Stationary Electrode in a Vertically-Driven MEMS Inertial Switch for Extending Contact Duration

PubMed Central

Xu, Qiu; Yang, Zhuo-Qing; Fu, Bo; Bao, Yan-Ping; Wu, Hao; Sun, Yun-Na; Zhao, Meng-Yuan; Li, Jian; Ding, Gui-Fu; Zhao, Xiao-Lin

2017-01-01

A novel micro-electro-mechanical systems (MEMS) inertial microswitch with a flexible contact-enhanced structure to extend the contact duration has been proposed in the present work. In order to investigate the stiffness k of the stationary electrodes, the stationary electrodes with different shapes, thickness h, width b, and length l were designed, analyzed, and simulated using ANSYS software. Both the analytical and the simulated results indicate that the stiffness k increases with thickness h and width b, while decreasing with an increase of length l, and it is related to the shape. The inertial micro-switches with different kinds of stationary electrodes were simulated using ANSYS software and fabricated using surface micromachining technology. The dynamic simulation indicates that the contact time will decrease with the increase of thickness h and width b, but increase with the length l, and it is related to the shape. As a result, the contact time decreases with the stiffness k of the stationary electrode. Furthermore, the simulated results reveal that the stiffness k changes more rapidly with h and l compared to b. However, overlarge dimension of the whole microswitch is contradicted with small footprint area expectation in the structure design. Therefore, it is unreasonable to extend the contact duration by increasing the length l excessively. Thus, the best and most convenient way to prolong the contact time is to reduce the thickness h of the stationary electrode while keeping the plane geometric structure of the inertial micro-switch unchanged. Finally, the fabricated micro-switches with different shapes of stationary electrodes have been evaluated by a standard dropping hammer system. The test maximum contact time under 288 g acceleration can reach 125 µs. It is shown that the test results are in accordance with the simulated results. The conclusions obtained in this work can provide guidance for the future design and fabrication of inertial microswitches. PMID:28272330

Design and Optimization of a Stationary Electrode in a Vertically-Driven MEMS Inertial Switch for Extending Contact Duration.

PubMed

Xu, Qiu; Yang, Zhuo-Qing; Fu, Bo; Bao, Yan-Ping; Wu, Hao; Sun, Yun-Na; Zhao, Meng-Yuan; Li, Jian; Ding, Gui-Fu; Zhao, Xiao-Lin

2017-03-07

A novel micro-electro-mechanical systems (MEMS) inertial microswitch with a flexible contact-enhanced structure to extend the contact duration has been proposed in the present work. In order to investigate the stiffness k of the stationary electrodes, the stationary electrodes with different shapes, thickness h , width b , and length l were designed, analyzed, and simulated using ANSYS software. Both the analytical and the simulated results indicate that the stiffness k increases with thickness h and width b , while decreasing with an increase of length l , and it is related to the shape. The inertial micro-switches with different kinds of stationary electrodes were simulated using ANSYS software and fabricated using surface micromachining technology. The dynamic simulation indicates that the contact time will decrease with the increase of thickness h and width b , but increase with the length l , and it is related to the shape. As a result, the contact time decreases with the stiffness k of the stationary electrode. Furthermore, the simulated results reveal that the stiffness k changes more rapidly with h and l compared to b . However, overlarge dimension of the whole microswitch is contradicted with small footprint area expectation in the structure design. Therefore, it is unreasonable to extend the contact duration by increasing the length l excessively. Thus, the best and most convenient way to prolong the contact time is to reduce the thickness h of the stationary electrode while keeping the plane geometric structure of the inertial micro-switch unchanged. Finally, the fabricated micro-switches with different shapes of stationary electrodes have been evaluated by a standard dropping hammer system. The test maximum contact time under 288 g acceleration can reach 125 µs. It is shown that the test results are in accordance with the simulated results. The conclusions obtained in this work can provide guidance for the future design and fabrication of inertial microswitches.

Integrated Micro-scale Power Conversion

DTIC Science & Technology

2012-08-01

Micro Power Converters (μPC) Loads: Sources: μ-Power Converter (μPC) Thin-film battery Solar Cell Micro- fuel Cell Vibration Harvester...passive size • Hybrid integration with MEMS passives, particularly inductors Hybrid integration ARL focus Bubble Size = Volume [mm3] Industry Focus...Power converters survey Compiled by Bedair, Bashirullah Switched inductor (SI) Switched capacitor (SC) Resonant Resonat piezo Hybrid - SI / SC

MEMS: A new approach to micro-optics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sniegowski, J.J.

1997-12-31

MicroElectroMechanical Systems (MEMS) and their fabrication technologies provide great opportunities for application to micro-optical systems (MOEMS). Implementing MOEMS technology ranges from simple, passive components to complicated, active systems. Here, an overview of polysilicon surface micromachining MEMS combined with optics is presented. Recent advancements to the technology, which may enhance its appeal for micro-optics applications are emphasized. Of all the MEMS fabrication technologies, polysilicon surface micromachining technology has the greatest basis in and leverages the most the infrastructure for silicon integrated circuit fabrication. In that respect, it provides the potential for very large volume, inexpensive production of MOEMS. This paper highlightsmore » polysilicon surface micromachining technology in regards to its capability to provide both passive and active mechanical elements with quality optical elements.« less

Design and Simulation of Optically Actuated Bistable MEMS

NASA Astrophysics Data System (ADS)

Lucas, Thomas; Moiseeva, Evgeniya; Harnett, Cindy

2012-02-01

In this project, bistable three-dimensional MEMS actuators are designed to be optically switched between stable states for biological research applications. The structure is a strained rectangular frame created with stress-mismatched metal-oxide bilayers. The devices curl into an arc in one of two directions tangent to the substrate, and can switch orientation when regions are selectively heated. The heating is powered by infrared laser, and localized with patterned infrared-resonant gold nanoparticles on critical regions. The enhanced energy absorption on selected areas provides switching control and heightened response to narrow-band infrared light. Coventorware has been used for finite element analysis of the system. The numerical simulations indicate that it has two local minimum states with extremely rapid transition time (<<0.1 s) when the structure is thermally deformed. Actuation at laser power and thermal limits compatible with physiological applications will enable microfluidic pumping elements and fundamental studies of tissue response to three-dimensional mechanical stimuli, artificial-muscle based pumps and other biomedical devices triggered by tissue-permeant infrared light.

New dynamic silicon photonic components enabled by MEMS technology

NASA Astrophysics Data System (ADS)

Errando-Herranz, Carlos; Edinger, Pierre; Colangelo, Marco; Björk, Joel; Ahmed, Samy; Stemme, Göran; Niklaus, Frank; Gylfason, Kristinn B.

2018-02-01

Silicon photonics is the study and application of integrated optical systems which use silicon as an optical medium, usually by confining light in optical waveguides etched into the surface of silicon-on-insulator (SOI) wafers. The term microelectromechanical systems (MEMS) refers to the technology of mechanics on the microscale actuated by electrostatic actuators. Due to the low power requirements of electrostatic actuation, MEMS components are very power efficient, making them well suited for dense integration and mobile operation. MEMS components are conventionally also implemented in silicon, and MEMS sensors such as accelerometers, gyros, and microphones are now standard in every smartphone. By combining these two successful technologies, new active photonic components with extremely low power consumption can be made. We discuss our recent experimental work on tunable filters, tunable fiber-to-chip couplers, and dynamic waveguide dispersion tuning, enabled by the marriage of silicon MEMS and silicon photonics.

Nanotechnology-Enhanced Lubricants for RF MEMS Switches

DTIC Science & Technology

2011-03-01

and have greater capabilities. 2.1. Problem Background The Air Force employs numerous communication links between space -borne assets, airborne...beyond 10B of rated cold-switched life, such as high-value space -borne assets with 12+ year horizons to deployment. Warm-switched operation refers to...lids for 5 min. at 300W in oxygen 5. Stud bump substrates using a gold- silver alloy wire bonder – packages may be stored 6. Tack seal pre-form to lid

MEMS-based Optic Fiber Fabry-Perot Sensor for Underwater Acoustic Measurement with A Wavelength-switched System

NASA Astrophysics Data System (ADS)

Xia, J.; Y Wang, F.; Luo, H.; Hu, Y. M.; Xiong, S. D.

2017-12-01

In this paper, a MEMS-based extrinsic Farby-Perot Interferometric (EFPI) acoustic pressure acoustic sensor is presented. The diaphragm structure is used as the second reflected surface, and the sensitive surface to acoustic pressure. A wavelength-switched phase demodulation system for EFPI sensors is used for acoustic signal recovery. The modified phase demodulation system has been demonstrated to recover the signal to a stable intensity fluctuation level of ±0.5 dB at the test frequency of 2000 Hz. In the test depth of 50cm, the sensor has a resonant frequency of 3.7 kHz, a flat frequency range of 10-800Hz, and a corresponding acoustic pressure sensitivity of -159 dB re. 1/μPa.

Concept and design of a beam blanker with integrated photoconductive switch for ultrafast electron microscopy.

PubMed

Weppelman, I G C; Moerland, R J; Hoogenboom, J P; Kruit, P

2018-01-01

We present a new method to create ultrashort electron pulses by integrating a photoconductive switch with an electrostatic deflector. This paper discusses the feasibility of such a system by analytical and numerical calculations. We argue that ultrafast electron pulses can be achieved for micrometer scale dimensions of the blanker, which are feasible with MEMS-based fabrication technology. According to basic models, the design presented in this paper is capable of generating 100 fs electron pulses with spatial resolutions of less than 10 nm. Our concept for an ultrafast beam blanker (UFB) may provide an attractive alternative to perform ultrafast electron microscopy, as it does not require modification of the microscope nor realignment between DC and pulsed mode of operation. Moreover, only low laser pulse energies are required. Due to its small dimensions the UFB can be inserted in the beam line of a commercial microscope via standard entry ports for blankers or variable apertures. The use of a photoconductive switch ensures minimal jitter between laser and electron pulses. Copyright © 2017 Elsevier B.V. All rights reserved.

MEMS for pico- to micro-satellites

NASA Astrophysics Data System (ADS)

Shea, H. R.

2009-02-01

MEMS sensors, actuators, and sub-systems can enable an important reduction in the size and mass of spacecrafts, first by replacing larger and heavier components, then by replacing entire subsystems, and finally by enabling the microfabrication of highly integrated picosats. Very small satellites (1 to 100 kg) stand to benefit the most from MEMS technologies. These small satellites are typically used for science or technology demonstration missions, with higher risk tolerance than multi-ton telecommunication satellites. While MEMS are playing a growing role on Earth in safety-critical applications, in the harsh and remote environment of space, reliability is still the crucial issue, and the absence of an accepted qualification methodology is holding back MEMS from wider use. An overview is given of the range of MEMS applications in space. An effective way to prove that MEMS can operate reliably in space is to use them in space: we illustrate how Cubesats (1 kg, 1 liter, cubic satellites in a standardized format to reduce launch costs) can serve as low-cost vectors for MEMS technology demonstration in space. The Cubesat SwissCube developed in Switzerland is used as one example of a rapid way to fly new microtechnologies, and also as an example of a spacecraft whose performance is only possible thanks to MEMS.

MEMS Using SOI Substrate

NASA Technical Reports Server (NTRS)

Tang, Tony K.

1999-01-01

At NASA, the focus for smaller, less costly missions has given impetus for the development of microspacecraft. MicroElectroMechanical System (MEMS) technology advances in the area of sensor, propulsion systems, and instruments, make the notion of a specialized microspacecraft feasible in the immediate future. Similar to the micro-electronics revolution,the emerging MEMS technology offers the integration of recent advances in micromachining and nanofabrication techniques with microelectronics in a mass-producible format,is viewed as the next step in device and instrument miniaturization. MEMS technology offers the potential of enabling or enhancing NASA missions in a variety of ways. This new technology allows the miniaturization of components and systems, where the primary benefit is a reduction in size, mass and power. MEMS technology also provides new capabilities and enhanced performance, where the most significant impact is in performance, regardless of system size. Finally,with the availability of mass-produced, miniature MEMS instrumentation comes the opportunity to rethink our fundamental measurement paradigms. It is now possible to expand our horizons from a single instrument perspective to one involving multi-node distributed systems. In the distributed systems and missions, a new system in which the functionality is enabled through a multiplicity of elements. Further in the future, the integration of electronics, photonics, and micromechanical functionalities into "instruments-on-a-chip" will provide the ultimate size, cost, function, and performance advantage. In this presentation, I will discuss recent development, requirement, and applications of various MEMS technologies and devices for space applications.

Optimal wavelength-space crossbar switches for supercomputer optical interconnects.

PubMed

Roudas, Ioannis; Hemenway, B Roe; Grzybowski, Richard R; Karinou, Fotini

2012-08-27

We propose a most economical design of the Optical Shared MemOry Supercomputer Interconnect System (OSMOSIS) all-optical, wavelength-space crossbar switch fabric. It is shown, by analysis and simulation, that the total number of on-off gates required for the proposed N × N switch fabric can scale asymptotically as N ln N if the number of input/output ports N can be factored into a product of small primes. This is of the same order of magnitude as Shannon's lower bound for switch complexity, according to which the minimum number of two-state switches required for the construction of a N × N permutation switch is log2 (N!).

Development of the micro pixel chamber based on MEMS technology

NASA Astrophysics Data System (ADS)

Takemura, T.; Takada, A.; Kishimoto, T.; Komura, S.; Kubo, H.; Matsuoka, Y.; Miuchi, K.; Miyamoto, S.; Mizumoto, T.; Mizumura, Y.; Motomura, T.; Nakamasu, Y.; Nakamura, K.; Oda, M.; Ohta, K.; Parker, J. D.; Sawano, T.; Sonoda, S.; Tanimori, T.; Tomono, D.; Yoshikawa, K.

2018-02-01

Micro pixel chambers (μ-PIC) are gaseous two-dimensional imaging detectors originally manufactured using printed circuit board (PCB) technology. They are used in MeV gamma-ray astronomy, medicalimaging, neutron imaging, the search for dark matter, and dose monitoring. The position resolution of the present μ-PIC is approximately 120 μm (RMS), however some applications require a fine position resolution of less than 100 μm. To this end, we have started to develop a μ-PIC based on micro electro mechanical system (MEMS) technology, which provides better manufacturing accuracy than PCB technology. Our simulation predicted the gains of MEMS μ-PICs to be twice those of PCB μ-PICs at the same anode voltage. We manufactured two MEMS μ-PICs and tested them to study their behavior. In these experiments, we successfully operated the fabricatedMEMS μ-PICs and we achieved a maximum gain of approximately 7×103 and collected their energy spectra under irradiation of X-rays from 55Fe. However, the measured gains of the MEMS μ-PICs were less than half of the values predicted in the simulations. We postulated that the gains of the MEMS μ-PICs are diminished by the effect of the silicon used as a semiconducting substrate.

Deep anisotropic ICP plasma etching designed for high-volume MEMS manufacturing

NASA Astrophysics Data System (ADS)

Yu, Keven; Feldbaum, Michael; Pandhumsoporn, Tam; Gadgil, Prashant

1999-08-01

ICP plasma etching is gaining widespread acceptance as an enabling micromachining technology for advanced MEMS fabrication. Whereas this technology has shown a capability of delivering multiple novel applications for R and D, its acceptance by industry for high volume production has been limited. This acceptance into production will only occur when the plasma etching equipment with this technology offers the device performance, throughput, reliability, and uptime criteria required by a production facility. The design of the plasma etcher using this technology and the process capability it consequently delivers, has significant implications in making this a reality. Alcatel has been supplying such a technology to this MEMS industry for over 5 years and in the interim has evolved its product and process to make this technology production worthy. Alcatel's next generation etcher, the Alcatel 601E, offers multiple advantages to MEMS manufacturers in realizing their production goals.

Control of solid-state lasers using an intra-cavity MEMS micromirror.

PubMed

Lubeigt, Walter; Gomes, Joao; Brown, Gordon; Kelly, Andrew; Savitski, Vasili; Uttamchandani, Deepak; Burns, David

2011-01-31

High reflectivity, electrothermal and electrostatic MEMS (Micro-Electro-Mechanical Systems) micromirrors were used as a control element within a Nd-doped laser cavity. Stable continuous-wave oscillation of a 3-mirror Nd:YLF laser at a maximum output power of 200 mW was limited by thermally-induced surface deformation of the micromirror. An electrostatic micromirror was used to induce Q-switching, resulting in pulse durations of 220 ns - 2 μs over a repetition frequency range of 6 kHz - 40 kHz.

MEMS capacitive pressure sensor monolithically integrated with CMOS readout circuit by using post CMOS processes

NASA Astrophysics Data System (ADS)

Jang, Munseon; Yun, Kwang-Seok

2017-12-01

In this paper, we presents a MEMS pressure sensor integrated with a readout circuit on a chip for an on-chip signal processing. The capacitive pressure sensor is formed on a CMOS chip by using a post-CMOS MEMS processes. The proposed device consists of a sensing capacitor that is square in shape, a reference capacitor and a readout circuitry based on a switched-capacitor scheme to detect capacitance change at various environmental pressures. The readout circuit was implemented by using a commercial 0.35 μm CMOS process with 2 polysilicon and 4 metal layers. Then, the pressure sensor was formed by wet etching of metal 2 layer through via hole structures. Experimental results show that the MEMS pressure sensor has a sensitivity of 11 mV/100 kPa at the pressure range of 100-400 kPa.

A dynamic system matching technique for improving the accuracy of MEMS gyroscopes

NASA Astrophysics Data System (ADS)

Stubberud, Peter A.; Stubberud, Stephen C.; Stubberud, Allen R.

2014-12-01

A classical MEMS gyro transforms angular rates into electrical values through Euler's equations of angular rotation. Production models of a MEMS gyroscope will have manufacturing errors in the coefficients of the differential equations. The output signal of a production gyroscope will be corrupted by noise, with a major component of the noise due to the manufacturing errors. As is the case of the components in an analog electronic circuit, one way of controlling the variability of a subsystem is to impose extremely tight control on the manufacturing process so that the coefficient values are within some specified bounds. This can be expensive and may even be impossible as is the case in certain applications of micro-electromechanical (MEMS) sensors. In a recent paper [2], the authors introduced a method for combining the measurements from several nominally equal MEMS gyroscopes using a technique based on a concept from electronic circuit design called dynamic element matching [1]. Because the method in this paper deals with systems rather than elements, it is called a dynamic system matching technique (DSMT). The DSMT generates a single output by randomly switching the outputs of several, nominally identical, MEMS gyros in and out of the switch output. This has the effect of 'spreading the spectrum' of the noise caused by the coefficient errors generated in the manufacture of the individual gyros. A filter can then be used to eliminate that part of the spread spectrum that is outside the pass band of the gyro. A heuristic analysis in that paper argues that the DSMT can be used to control the effects of the random coefficient variations. In a follow-on paper [4], a simulation of a DSMT indicated that the heuristics were consistent. In this paper, analytic expressions of the DSMT noise are developed which confirm that the earlier conclusions are valid. These expressions include the various DSMT design parameters and, therefore, can be used as design tools for DSMT systems.

A dynamic system matching technique for improving the accuracy of MEMS gyroscopes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stubberud, Peter A., E-mail: stubber@ee.unlv.edu; Stubberud, Stephen C., E-mail: scstubberud@ieee.org; Stubberud, Allen R., E-mail: stubberud@att.net

A classical MEMS gyro transforms angular rates into electrical values through Euler's equations of angular rotation. Production models of a MEMS gyroscope will have manufacturing errors in the coefficients of the differential equations. The output signal of a production gyroscope will be corrupted by noise, with a major component of the noise due to the manufacturing errors. As is the case of the components in an analog electronic circuit, one way of controlling the variability of a subsystem is to impose extremely tight control on the manufacturing process so that the coefficient values are within some specified bounds. This canmore » be expensive and may even be impossible as is the case in certain applications of micro-electromechanical (MEMS) sensors. In a recent paper [2], the authors introduced a method for combining the measurements from several nominally equal MEMS gyroscopes using a technique based on a concept from electronic circuit design called dynamic element matching [1]. Because the method in this paper deals with systems rather than elements, it is called a dynamic system matching technique (DSMT). The DSMT generates a single output by randomly switching the outputs of several, nominally identical, MEMS gyros in and out of the switch output. This has the effect of 'spreading the spectrum' of the noise caused by the coefficient errors generated in the manufacture of the individual gyros. A filter can then be used to eliminate that part of the spread spectrum that is outside the pass band of the gyro. A heuristic analysis in that paper argues that the DSMT can be used to control the effects of the random coefficient variations. In a follow-on paper [4], a simulation of a DSMT indicated that the heuristics were consistent. In this paper, analytic expressions of the DSMT noise are developed which confirm that the earlier conclusions are valid. These expressions include the various DSMT design parameters and, therefore, can be used as design tools for DSMT systems.« less

Use of silicon oxynitride as a sacrificial material for microelectromechanical devices

DOEpatents

Habermehl, Scott D.; Sniegowski, Jeffry J.

2001-01-01

The use of silicon oxynitride (SiO.sub.x N.sub.y) as a sacrificial material for forming a microelectromechanical (MEM) device is disclosed. Whereas conventional sacrificial materials such as silicon dioxide and silicate glasses are compressively strained, the composition of silicon oxynitride can be selected to be either tensile-strained or substantially-stress-free. Thus, silicon oxynitride can be used in combination with conventional sacrificial materials to limit an accumulation of compressive stress in a MEM device; or alternately the MEM device can be formed entirely with silicon oxynitride. Advantages to be gained from the use of silicon oxynitride as a sacrificial material for a MEM device include the formation of polysilicon members that are substantially free from residual stress, thereby improving the reliability of the MEM device; an ability to form the MEM device with a higher degree of complexity and more layers of structural polysilicon than would be possible using conventional compressively-strained sacrificial materials; and improved manufacturability resulting from the elimination of wafer distortion that can arise from an excess of accumulated stress in conventional sacrificial materials. The present invention is useful for forming many different types of MEM devices including accelerometers, sensors, motors, switches, coded locks, and flow-control devices, with or without integrated electronic circuitry.

MEMS sensing and control: an aerospace perspective

NASA Astrophysics Data System (ADS)

Schoess, Jeffrey N.; Arch, David K.; Yang, Wei; Cabuz, Cleopatra; Hocker, Ben; Johnson, Burgess R.; Wilson, Mark L.

2000-06-01

Future advanced fixed- and rotary-wing aircraft, launch vehicles, and spacecraft will incorporate smart microsensors to monitor flight integrity and provide flight control inputs. This paper provides an overview of Honeywell's MEMS technologies for aerospace applications of sensing and control. A unique second-generation polysilicon resonant microbeam sensor design is described. It incorporates a micron-level vacuum-encapsulated microbeam to optically sense aerodynamic parameters and to optically excite the sensor pick off: optically excited self-resonant microbeams form the basis for a new class of versatile, high- performance, low-cost MEMS sensors that uniquely combine silicon microfabrication technology with optoelectronic technology that can sense dynamic pressure, acceleration forces, acoustic emission, and many other aerospace parameters of interest. Honeywell's recent work in MEMS tuning fork gyros for inertial sensing and a MEMS free- piston engine are also described.

A novel micro/nano 1 × 4 mechanical optical switch

NASA Astrophysics Data System (ADS)

Lin, Wu-Lang; Fan, Kuang-Chao; Chiang, Li-Hung; Yang, Yao-Joe; Kuo, Wen-Cheng; Chung, Tien-Tung

2006-07-01

This paper presents the design, fabrication and testing of a novel 1 × 4 mechanical optical switch, whose components are fabricated by precision machining and MEMS technologies. The switch uses two relays as the two actuators whose switching direction is perpendicular to each other by an orthogonal arrangement. We adopt a direct fiber-to-fiber principle that aligns the input fiber directly to four output fibers. This configuration eliminates the use of traditional parts such as collimators, turning mirrors or prisms. In addition, due to the use of a fiber holder, the fiber position errors could be reduced to less than 0.27 µm using the two-stage geometry error reduction principle. We have successfully developed a simple and low-cost switch, which performs like most of the 1 × 4 mechanical optical switches that dominate the optics communications market. The advantages of our switch are a small size (20 × 20 × 25 mm3), low cost, high reliability, and the latching function does not need external force for maintaining the state. The experimental results showed that the insertion losses of the four channels are ch1: 0.68 dB, ch2: 1.49 dB, ch3: 0.71 dB and ch4: 0.97 dB. The switching time is 5 ms, the crosstalk <=80 dB. The reliability tests of the insertion loss after 10 000 cycles in four channels yield ch1: 1.67 dB, ch2: 1.63 dB, ch3: 0.75 dB and ch4: 0.98 dB. The size and the cost of our 1 × 4 mechanical optical switch are only about 1/5-1/10 and 1/10 of the series-connect-type and prism-type switches, respectively.

Exploration of MEMS G-Switches at 100-10,000 G-Levels with Redundancy

DTIC Science & Technology

2014-04-01

Muntz, A.D. Ketsdever, “Kinetic Modeling of Temperature -Driven Flows in Short Microchannels,” International Journal of Thermal Sciences, Vol. 45, No...switches silicon DRIE Unclassified Unclassified Unclassified UU 59 Suhithi Peiris 703-767-4732 CONVERSION...designed. The devices were fabricated on low resistivity (ɘ.01 Ω-cm) silicon on insulator wafers (SOI) using standard micromachining techniques. Fixed

Reliability enhancement of Ohmic RF MEMS switches

NASA Astrophysics Data System (ADS)

Kurth, Steffen; Leidich, Stefan; Bertz, Andreas; Nowack, Markus; Frömel, Jörg; Kaufmann, Christian; Faust, Wolfgang; Gessner, Thomas; Akiba, Akira; Ikeda, Koichi

2011-02-01

This contribution deals with capacitively actuated Ohmic switches in series single pole single throw (SPST) configuration for DC up to 4 GHz signal frequency (<0.5 dB insertion loss, 35 dB isolation) and in shunt switch SPST configuration for a frequency range from DC up to 80 GHz (<1.2 dB insertion loss, 18 dB isolation at 60 GHz). A novel high aspect ratio MEMS fabrication sequence in combination with wafer level packaging is applied for fabrication of the samples and allows for a relatively large actuation electrode area, and for high actuation force resulting in fast onresponse time of 10 μs and off-response time of 6 μs at less than 5 V actuation voltage. Large actuation electrode area and a particular design feature for electrode over travel and dynamic contact separation lead to high contact force in the closed state and to high force for contact separation to overcome sticking. The switch contacts, which are consisting of noble metal, are made in one of the latest process steps. This minimizes contamination of the contact surfaces by fabrication sequence residuals. A life time of 1 Billion switch cycles has been achieved. This paper covers design for reliability issues and reliability test methods using accelerated life time test. Different test methods are combined to examine electric and mechanical motion parameters as well as RF performance.

Meso scale MEMS inertial switch fabricated using an electroplated metal-on-insulator process

NASA Astrophysics Data System (ADS)

Gerson, Y.; Schreiber, D.; Grau, H.; Krylov, S.

2014-02-01

In this work, we report on a novel simple yet robust two-mask metal-on-insulator (MOI) process and illustrate its implementation for the fabrication of a meso scale MEMS inertial switch. The devices were fabricated of a ˜40 µm thick layer of nickel electrodeposited on top of a 4 µm thick thermal field oxide (TOX) covering a single crystal silicon wafer. A 40 µm thick layer of KMPR® resist was used as a mold and allowed the formation of high-aspect-ratio (1:5) metal structures. The devices were released by the sacrificial etching of the TOX layer in hydrofluoric acid. The fabricated devices were mounted in a ceramic enclosure and were characterized using both an electromagnet shaker and a drop tester. The functionality of the switch, aimed to trigger an electrical circuit when subjected to an acceleration pulse with amplitude of 300 g and duration of 200 µs, was demonstrated experimentally and the performance targets were achieved. The experimental results were consistent with the model predictions obtained through finite element simulations.

The role of creep in the time-dependent resistance of Ohmic gold contacts in radio frequency microelectromechanical system devices

NASA Astrophysics Data System (ADS)

Rezvanian, O.; Brown, C.; Zikry, M. A.; Kingon, A. I.; Krim, J.; Irving, D. L.; Brenner, D. W.

2008-07-01

It is shown that measured and calculated time-dependent electrical resistances of closed gold Ohmic switches in radio frequency microelectromechanical system (rf-MEMS) devices are well described by a power law that can be derived from a single asperity creep model. The analysis reveals that the exponent and prefactor in the power law arise, respectively, from the coefficient relating creep rate to applied stress and the initial surface roughness. The analysis also shows that resistance plateaus are not, in fact, limiting resistances but rather result from the small coefficient in the power law. The model predicts that it will take a longer time for the contact resistance to attain a power law relation with each successive closing of the switch due to asperity blunting. Analysis of the first few seconds of the measured resistance for three successive openings and closings of one of the MEMS devices supports this prediction. This work thus provides guidance toward the rational design of Ohmic contacts with enhanced reliabilities by better defining variables that can be controlled through material selection, interface processing, and switch operation.

Track Detection in Railway Sidings Based on MEMS Gyroscope Sensors

PubMed Central

Broquetas, Antoni; Comerón, Adolf; Gelonch, Antoni; Fuertes, Josep M.; Castro, J. Antonio; Felip, Damià; López, Miguel A.; Pulido, José A.

2012-01-01

The paper presents a two-step technique for real-time track detection in single-track railway sidings using low-cost MEMS gyroscopes. The objective is to reliably know the path the train has taken in a switch, diverted or main road, immediately after the train head leaves the switch. The signal delivered by the gyroscope is first processed by an adaptive low-pass filter that rejects noise and converts the temporal turn rate data in degree/second units into spatial turn rate data in degree/meter. The conversion is based on the travelled distance taken from odometer data. The filter is implemented to achieve a speed-dependent cut-off frequency to maximize the signal-to-noise ratio. Although direct comparison of the filtered turn rate signal with a predetermined threshold is possible, the paper shows that better detection performance can be achieved by processing the turn rate signal with a filter matched to the rail switch curvature parameters. Implementation aspects of the track detector have been optimized for real-time operation. The detector has been tested with both simulated data and real data acquired in railway campaigns. PMID:23443376

Novel First-Level Interconnect Techniques for Flip Chip on MEMS Devices

PubMed Central

Sutanto, Jemmy; Anand, Sindhu; Patel, Chetan; Muthuswamy, Jit

2013-01-01

Flip-chip packaging is desirable for microelectro-mechanical systems (MEMS) devices because it reduces the overall package size and allows scaling up the number of MEMS chips through 3-D stacks. In this report, we demonstrate three novel techniques to create first-level interconnect (FLI) on MEMS: 1) Dip and attach technology for Ag epoxy; 2) Dispense technology for solder paste; 3) Dispense, pull, and attach technology (DPAT) for solder paste. The above techniques required no additional microfabrication steps, produced no visible surface contamination on the MEMS active structures, and generated high-aspect-ratio interconnects. The developed FLIs were successfully tested on MEMS moveable microelectrodes microfabricated by SUMMiTVTM process producing no apparent detrimental effect due to outgassing. The bumping processes were successfully applied on Al-deposited bond pads of 100 μm × 100 μm with an average bump height of 101.3 μm for Ag and 184.8 μm for solder (63Sn, 37Pb). DPAT for solder paste produced bumps with the aspect ratio of 1.8 or more. The average shear strengths of Ag and solder bumps were 78 MPa and 689 kPa, respectively. The electrical test on Ag bumps at 794 A/cm2 demonstrated reliable electrical interconnects with negligible resistance. These scalable FLI technologies are potentially useful for MEMS flip-chip packaging and 3-D stacking. PMID:24504168

Miniaturization of components and systems for space using MEMS-technology

NASA Astrophysics Data System (ADS)

Grönland, Tor-Arne; Rangsten, Pelle; Nese, Martin; Lang, Martin

2007-06-01

Development of MEMS-based (micro electro mechanical system) components and subsystems for space applications has been pursued by various research groups and organizations around the world for at least two decades. The main driver for developing MEMS-based components for space is the miniaturization that can be achieved. Miniaturization can not only save orders of magnitude in mass and volume of individual components, but it can also allow increased redundancy, and enable novel spacecraft designs and mission scenarios. However, the commercial breakthrough of MEMS has not occurred within the space business as it has within other branches such as the IT/telecom or automotive industries, or as it has in biotech or life science applications. A main explanation to this is the highly conservative attitude to new technology within the space community. This conservatism is in many senses motivated by a very low risk acceptance in the few and costly space projects that actually ends with a space flight. To overcome this threshold there is a strong need for flight opportunities where reasonable risks can be accepted. Currently there are a few flight opportunities allowing extensive use of new technology in space, but one of the exceptions is the PRISMA program. PRISMA is an international (Sweden, Germany, France, Denmark, Norway, Greece) technology demonstration program with focus on rendezvous and formation flying. It is a two satellite LEO mission with a launch scheduled for the first half of 2009. On PRISMA, a number of novel technologies e.g. RF metrology sensor for Darwin, autonomous formation flying based on GPS and vision-based sensors, ADN-based "green propulsion" will be demonstrated in space for the first time. One of the satellites will also have a miniaturized propulsion system onboard based on MEMS-technology. This novel propulsion system includes two microthruster modules, each including four thrusters with micro- to milli-Newton thrust capability. The novelty of this micropropulsion system is that all critical components such as thrust chamber/nozzle assembly including internal heaters, valves and filters are manufactured using MEMS technology. Moreover, miniaturized pressure sensors, relying on MEMS technology, is also part of the system as a self-standing component. The flight opportunity on PRISMA represents one of the few and thus important opportunities to demonstrate MEMS technology in space. The present paper aims at describing this development effort and highlights the benefits of miniaturized components and systems for space using MEMS technology.

78 FR 22529 - Notice of Availability of Government-Owned Inventions; Available for Licensing

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-16

.... 101875: INERTIAL SENSORS USING SLIDING PLANE ELECTRON TUNNELING PROXIMITY SWITCHES//Navy Case No. 102181... TRIGGER FOR USE IN TIME-DOMAIN MEMS INERTIAL SENSORS. FOR FURTHER INFORMATION CONTACT: Brian Suh, Office...

Electrofluidic systems for contrast management

NASA Astrophysics Data System (ADS)

Rebello, Keith J.; Maranchi, Jeffrey P.; Tiffany, Jason E.; Brown, Christopher Y.; Maisano, Adam J.; Hagedon, Matthew A.; Heikenfeld, Jason C.

2012-06-01

Operating in dynamic lighting conditions and in greatly varying backgrounds is challenging. Current paints and state-ofthe- art passive adaptive coatings (e.g. photochromics) are not suitable for multi- environment situations. A semi-active, low power, skin is needed that can adapt its reflective properties based on the background environment to minimize contrast through the development and incorporation of suitable pigment materials. Electrofluidic skins are a reflective display technology for electronic ink and paper applications. The technology is similar to that in E Ink but makes use of MEMS based microfluidic structures, instead of simple black and white ink microcapsules dispersed in clear oil. Electrofluidic skin's low power operation and fast switching speeds (~20 ms) are an improvement over current state-ofthe- art contrast management technologies. We report on a microfluidic display which utilizes diffuse pigment dispersion inks to change the contrast of the underlying substrate from 5.8% to 100%. Voltage is applied and an electromechanical pressure is used to pull a pigment dispersion based ink from a hydrophobic coated reservoir into a hydrophobic coated surface channel. When no voltage is applied, the Young-Laplace pressure pushes the pigment dispersion ink back down into the reservoir. This allows the pixel to switch from the on and off state by balancing the two pressures. Taking a systems engineering approach from the beginning of development has enabled the technology to be integrated into larger systems.

Dynamically reconfigurable optical packet switch (DROPS)

NASA Astrophysics Data System (ADS)

Huang, Chi-Heng; Chou, Hsu-Feng; Bowers, John E.; Toudeh-Fallah, Farzam; Gyurek, Russ

2006-12-01

A novel Dynamically Reconfigurable Optical Packet Switch (DROPS) that combines both spectral and spatial switching capabilities is proposed and experimentally demonstrated for the first time. Compared with an Arrayed Waveguide Grating Router (AWGR), the added spatial switching capability provided by the microelectromechanical systems (MEMS) enables dynamically reconfigurable routing that is not possible with an AWGR alone. This methodology has several advantages over an AWGR including scalability, additional degrees of freedom in routing a packet from an ingress port to an egress port and more flexibility in path or line card recovery. The experimental demonstration implemented with 10-Gb/s packets shows that the added spatial switching does not degrade the bit-error-rate performance, indicating the promising potential of DROPS as a versatile and ultra-high capacity switch for optical packet-switched networks.

Fabricating and using a micromachined magnetostatic relay or switch

NASA Technical Reports Server (NTRS)

Tai, Yu-Chong (Inventor); Wright, John A. (Inventor)

2001-01-01

A micromachined magnetostatic relay or switch includes a springing beam on which a magnetic actuation plate is formed. The springing beam also includes an electrically conductive contact. In the presence of a magnetic field, the magnetic material causes the springing beam to bend, moving the electrically conductive contact either toward or away from another contact, and thus creating either an electrical short-circuit or an electrical open-circuit. The switch is fabricated from silicon substrates and is particularly useful in forming a MEMs commutation and control circuit for a miniaturized DC motor.

Validation of bending tests by nanoindentation for micro-contact analysis of MEMS switches

NASA Astrophysics Data System (ADS)

Broue, Adrien; Fourcade, Thibaut; Dhennin, Jérémie; Courtade, Frédéric; Charvet, Pierre–Louis; Pons, Patrick; Lafontan, Xavier; Plana, Robert

2010-08-01

Research on contact characterization for microelectromechanical system (MEMS) switches has been driven by the necessity to reach a high-reliability level for micro-switch applications. One of the main failures observed during cycling of the devices is the increase of the electrical contact resistance. The key issue is the electromechanical behaviour of the materials used at the contact interface where the current flows through. Metal contact switches have a large and complex set of failure mechanisms according to the current level. This paper demonstrates the validity of a new methodology using a commercial nanoindenter coupled with electrical measurements on test vehicles specially designed to investigate the micro-scale contact physics. Dedicated validation tests and modelling are performed to assess the introduced methodology by analyzing the gold contact interface with 5 µm2 square bumps at various current levels. Contact temperature rise is measured, which affects the mechanical properties of the contact materials and modifies the contact topology. In addition, the data provide a better understanding of micro-contact behaviour related to the impact of current at low- to medium-power levels. This article was originally submitted for the special section 'Selected papers from the 20th Micromechanics Europe Workshop (MME 09) (Toulouse, France, 20-22 September 2009)', Journal of Micromechanics and Microengineering, volume 20, issue 6.

U.S. Army Corrosion Office's storage and quality requirements for military MEMS program

NASA Astrophysics Data System (ADS)

Zunino, J. L., III; Skelton, D. R.

2007-04-01

As the Army transforms into a more lethal, lighter and agile force, the technologies that support these systems must decrease in size while increasing in intelligence. Micro-electromechanical systems (MEMS) are one such technology that the Army and DOD will rely on heavily to accomplish these objectives. Conditions for utilization of MEMS by the military are unique. Operational and storage environments for the military are significantly different than those found in the commercial sector. Issues unique to the military include; high G-forces during gun launch, extreme temperature and humidity ranges, extended periods of inactivity (20 years plus) and interaction with explosives and propellants. The military operational environments in which MEMS will be stored or required to function are extreme and far surpass any commercial operating conditions. Security and encryption are a must for all MEMS communication, tracking, or data reporting devices employed by the military. Current and future military applications of MEMS devices include safety and arming devices, fuzing devices, various guidance systems, sensors/detectors, inertial measurement units, tracking devices, radio frequency devices, wireless Radio Frequency Identifications (RFIDs) and network systems, GPS's, radar systems, mobile base systems and information technology. MEMS embedded into these weapons systems will provide the military with new levels of speed, awareness, lethality, and information dissemination. The system capabilities enhanced by MEMS will translate directly into tactical and strategic military advantages.

Microelectromechanical Systems for Aerodynamics Applications

NASA Technical Reports Server (NTRS)

Mehregany, Mehran; DeAnna, Russell G.; Reshotko, Eli

1996-01-01

Microelectromechanical systems (MEMS) embody the integration of sensors, actuators, and electronics on a single substrate using integrated circuit fabrication techniques and compatible micromachining processes. Silicon and its derivatives form the material base for the MEMS technology. MEMS devices, including micro-sensors and micro-actuators, are attractive because they can be made small (characteristic dimension about microns), be produced in large numbers with uniform performance, include electronics for high performance and sophisticated functionality, and be inexpensive. MEMS pressure sensors, wall-shear-stress sensors, and micromachined hot-wires are nearing application in aeronautics. MEMS actuators face a tougher challenge since they have to be scaled (up) to the physical phenomena that are being controlled. MEMS actuators are proposed, for example, for controlling the small structures in a turbulent boundary layer, for aircraft control, for cooling, and for mixing enhancement. Data acquisition or control logistics require integration of electronics along with the transducer elements with appropriate consideration of analog-to-digital conversion, multiplexing, and telemetry. Altogether, MEMS technology offers exciting opportunities for aerodynamics applications both in wind tunnels and in flight

The Impact of Dielectric Material and Temperature on Dielectric Charging in RF MEMS Capacitive Switches

NASA Astrophysics Data System (ADS)

Papaioannou, George

The present work attempts to provide a better insight on the dielectric charging in RF-MEMS capacitive switches that constitutes a key issue limiting parameter of their commercialization. The dependence of the charging process on the nature of dielectric materials widely used in these devices, such as SiO2, Si3N4, AlN, Al2O3, Ta2O5, HfO2, which consist of covalent or ionic bonds and may exhibit piezoelectric properties is discussed taking into account the effect of deposition conditions and resulting material stoichiometry. Another key issue parameter that accelerates the charging and discharging processes by providing enough energy to trapped charges to be released and to dipoles to overcome potential barriers and randomize their orientation is the temperature will be investigated too. Finally, the effect of device structure will be also taken into account.

MEMS Device Being Developed for Active Cooling and Temperature Control

NASA Technical Reports Server (NTRS)

Moran, Matthew E.

2001-01-01

High-capacity cooling options remain limited for many small-scale applications such as microelectronic components, miniature sensors, and microsystems. A microelectromechanical system (MEMS) is currently under development at the NASA Glenn Research Center to meet this need. It uses a thermodynamic cycle to provide cooling or heating directly to a thermally loaded surface. The device can be used strictly in the cooling mode, or it can be switched between cooling and heating modes in milliseconds for precise temperature control. Fabrication and assembly are accomplished by wet etching and wafer bonding techniques routinely used in the semiconductor processing industry. Benefits of the MEMS cooler include scalability to fractions of a millimeter, modularity for increased capacity and staging to low temperatures, simple interfaces and limited failure modes, and minimal induced vibration.

A novel multi-level IC-compatible surface microfabrication technology for MEMS with independently controlled lateral and vertical submicron transduction gaps

NASA Astrophysics Data System (ADS)

Cicek, Paul-Vahe; Elsayed, Mohannad; Nabki, Frederic; El-Gamal, Mourad

2017-11-01

An above-IC compatible multi-level MEMS surface microfabrication technology based on a silicon carbide structural layer is presented. The fabrication process flow provides optimal electrostatic transduction by allowing the creation of independently controlled submicron vertical and lateral gaps without the need for high resolution lithography. Adopting silicon carbide as the structural material, the technology ensures material, chemical and thermal compatibility with modern semiconductor nodes, reporting the lowest peak processing temperature (i.e. 200 °C) of all comparable works. This makes this process ideally suited for integrating capacitive-based MEMS directly above standard CMOS substrates. Process flow design and optimization are presented in the context of bulk-mode disk resonators, devices that are shown to exhibit improved performance with respect to previous generation flexural beam resonators, and that represent relatively complex MEMS structures. The impact of impending improvements to the fabrication technology is discussed.

MEMS-based beam-steerable free-space optical communication link for reconfigurable wireless data center

NASA Astrophysics Data System (ADS)

Deng, Peng; Kavehrad, Mohsen; Lou, Yan

2017-01-01

Flexible wireless datacenter networks based on free space optical communication (FSO) links are being considered as promising solutions to meet the future datacenter demands of high throughput, robustness to dynamic traffic patterns, cabling complexity and energy efficiency. Robust and precise steerable FSO links over dynamic traffic play a key role in the reconfigurable optical wireless datacenter inter-rack network. In this work, we propose and demonstrate a reconfigurable 10Gbps FSO system incorporated with smart beam acquisition and tracking mechanism based on gimballess two-axis MEMS micro-mirror and retro-reflective film marked aperture. The fast MEMS-based beam acquisition switches laser beam of FSO terminal from one rack to the next for reconfigurable networks, and the precise beam tracking makes FSO device auto-correct the misalignment in real-time. We evaluate the optical power loss and bit error rate performance of steerable FSO links at various directions. Experimental results suggest that the MEMS based beam steerable FSO links hold considerable promise for the future reconfigurable wireless datacenter networks.

Integrated MEMS-based variable optical attenuator and 10Gb/s receiver

NASA Astrophysics Data System (ADS)

Aberson, James; Cusin, Pierre; Fettig, H.; Hickey, Ryan; Wylde, James

2005-03-01

MEMS devices can be successfully commercialized in favour of competing technologies only if they offer an advantage to the customer in terms of lower cost or increased functionality. There are limited markets where MEMS can be manufactured cheaper than similar technologies due to large volumes: automotive, printing technology, wireless communications, etc. However, success in the marketplace can also be realized by adding significant value to a system at minimal cost or leverging MEMS technology when other solutions simply will not work. This paper describes a thermally actuated, MEMS based, variable optical attenuator that is co-packaged with existing opto-electronic devices to develop an integrated 10Gb/s SONET/SDH receiver. The configuration of the receiver opto-electronics and relatively low voltage availability (12V max) in optical systems bar the use of LCD, EO, and electro-chromic style attenuators. The device was designed and fabricated using a silicon-on-insulator (SOI) starting material. The design and performance of the device (displacement, power consumption, reliability, physical geometry) was defined by the receiver parameters geometry. This paper will describe how these design parameters (hence final device geometry) were determined in light of both the MEMS device fabrication process and the receiver performance. Reference will be made to the design tools used and the design flow which was a joint effort between the MEMS vendor and the end customer. The SOI technology offered a robust, manufacturable solution that gave the required performance in a cost-effective process. However, the singulation of the devices required the development of a new singulation technique that allowed large volumes of silicon to be removed during fabrication yet still offer high singulation yields.

BioMEMS for biosensors and closed-loop drug delivery.

PubMed

Coffel, Joel; Nuxoll, Eric

2018-06-15

The efficacy of pharmaceutical treatments can be greatly enhanced by physiological feedback from the patient using biosensors, though this is often invasive or infeasible. By adapting microelectromechanical systems (MEMS) technology to miniaturize such biosensors, previously inaccessible signals can be obtained, often from inside the patient. This is enabled by the device's extremely small footprint which minimizes both power consumption and implantation trauma, as well as the transport time for chemical analytes, in turn decreasing the sensor's response time. MEMS fabrication also allows mass production which can be easily scaled without sacrificing its high reproducibility and reliability, and allows seamless integration with control circuitry and telemetry which is already produced using the same materials and fabrication steps. By integrating these systems with drug delivery devices, many of which are also MEMS-based, closed loop drug delivery can be achieved. This paper surveys the types of signal transduction devices available for biosensing-primarily electrochemical, optical, and mechanical-looking at their implementation via MEMS technology. The impact of MEMS technology on the challenges of biosensor development, particularly safety, power consumption, degradation, fouling, and foreign body response, are also discussed. Copyright © 2018 Elsevier B.V. All rights reserved.

EDITORIAL: International MEMS Conference 2006

NASA Astrophysics Data System (ADS)

Tay, Francis E. H.; Jianmin, Miao; Iliescu, Ciprian

2006-04-01

The International MEMS conference (iMEMS2006) organized by the Institute of Bioengineering and Nanotechnology and Nanyang Technological University aims to provide a platform for academicians, professionals and industrialists in various related fields from all over the world to share and learn from each other. Of great interest is the incorporation of the theme of life sciences application using MEMS. It is the desire of this conference to initiate collaboration and form network of cooperation. This has continued to be the objective of iMEMS since its inception in 1997. The technological advance of MEMS over the past few decades has been truly exciting in terms of development and applications. In order to participate in this rapid development, a conference involving delegates from within the MEMS community and outside the community is very meaningful and timely. With the receipt of over 200 articles, delegates related to MEMS field from all over the world will share their perspectives on topics such as MEMS/MST Design, MEMS Teaching and Education, MEMS/MST Packaging, MEMS/MST Fabrication, Microsystems Applications, System Integration, Wearable Devices, MEMSWear and BioMEMS. Invited speakers and delegates from outside the field have also been involved to provide challenges, especially in the life sciences field, for the MEMS community to potentially address. The proceedings of the conference will be published as an issue in the online Journal of Physics: Conference Series and this can reach a wider audience and will facilitate the reference and citation of the work presented in the conference. We wish to express our deep gratitude to the International Scientific Committee members and the organizing committee members for contributing to the success of this conference. We would like to thank all the delegates, speakers and sponsors from all over the world for presenting and sharing their perspectives on topics related to MEMS and the challenges that MEMS can potentially address.

Additive direct-write microfabrication for MEMS: A review

NASA Astrophysics Data System (ADS)

Teh, Kwok Siong

2017-12-01

Direct-write additive manufacturing refers to a rich and growing repertoire of well-established fabrication techniques that builds solid objects directly from computer- generated solid models without elaborate intermediate fabrication steps. At the macroscale, direct-write techniques such as stereolithography, selective laser sintering, fused deposition modeling ink-jet printing, and laminated object manufacturing have significantly reduced concept-to-product lead time, enabled complex geometries, and importantly, has led to the renaissance in fabrication known as the maker movement. The technological premises of all direct-write additive manufacturing are identical—converting computer generated three-dimensional models into layers of two-dimensional planes or slices, which are then reconstructed sequentially into threedimensional solid objects in a layer-by-layer format. The key differences between the various additive manufacturing techniques are the means of creating the finished layers and the ancillary processes that accompany them. While still at its infancy, direct-write additive manufacturing techniques at the microscale have the potential to significantly lower the barrier-of-entry—in terms of cost, time and training—for the prototyping and fabrication of MEMS parts that have larger dimensions, high aspect ratios, and complex shapes. In recent years, significant advancements in materials chemistry, laser technology, heat and fluid modeling, and control systems have enabled additive manufacturing to achieve higher resolutions at the micrometer and nanometer length scales to be a viable technology for MEMS fabrication. Compared to traditional MEMS processes that rely heavily on expensive equipment and time-consuming steps, direct-write additive manufacturing techniques allow for rapid design-to-prototype realization by limiting or circumventing the need for cleanrooms, photolithography and extensive training. With current direct-write additive manufacturing technologies, it is possible to fabricate unsophisticated micrometer scale structures at adequate resolutions and precisions using materials that range from polymers, metals, ceramics, to composites. In both academia and industry, direct-write additive manufacturing offers extraordinary promises to revolutionize research and development in microfabrication and MEMS technologies. Importantly, direct-write additive manufacturing could appreciably augment current MEMS fabrication technologies, enable faster design-to-product cycle, empower new paradigms in MEMS designs, and critically, encourage wider participation in MEMS research at institutions or for individuals with limited or no access to cleanroom facilities. This article aims to provide a limited review of the current landscape of direct-write additive manufacturing techniques that are potentially applicable for MEMS microfabrication.

MEMS microphone innovations towards high signal to noise ratios (Conference Presentation) (Plenary Presentation)

NASA Astrophysics Data System (ADS)

Dehé, Alfons

2017-06-01

After decades of research and more than ten years of successful production in very high volumes Silicon MEMS microphones are mature and unbeatable in form factor and robustness. Audio applications such as video, noise cancellation and speech recognition are key differentiators in smart phones. Microphones with low self-noise enable those functions. Backplate-free microphones enter the signal to noise ratios above 70dB(A). This talk will describe state of the art MEMS technology of Infineon Technologies. An outlook on future technologies such as the comb sensor microphone will be given.

A CMOS-MEMS clamped–clamped beam displacement amplifier for resonant switch applications

NASA Astrophysics Data System (ADS)

Liu, Jia-Ren; Lu, Shih-Chuan; Tsai, Chun-Pu; Li, Wei-Chang

2018-06-01

This paper presents a micromechanical clamped–clamped beam (CC-beam) displacement amplifier based on a CMOS-MEMS fabrication process platform. In particular, a 2.0 MHz resonant displacement amplifier composed of two identical CC-beams coupled by a mechanical beam at locations where the two beams have mismatched velocities exhibits a larger displacement, up to 9.96×, on one beam than that of the other. The displacement amplification prevents unwanted input impacting—the structure switches only to the output but not the input—required by resonant switch-based mechanical circuits (Kim et al 2009 22nd IEEE Int. Conf. on Micro Electro Mechanical Systems; Lin et al 2009 15th Int. Conf. on Solid-State Sensors, Actuators, & Microsystems (TRANSDUCERS’09) Li et al 2013 17th Int. Conf. on Solid-State Sensors, Actuators, & Microsystems (TRANSDUCERS’13)). Compared to a single CC-beam displacement amplifier, theory predicts that the displacement amplifying CC-beam array yields a larger overall output displacement for displacement gain beyond 1.13 thanks to the preserved input driving force. A complete analytical model predicts the resultant stiffness and displacement gain of the coupled CC-beam displacement amplifier that match well with finite element analysis (FEA) prediction and measured results.

Piezoelectric MEMS: Ferroelectric thin films for MEMS applications

NASA Astrophysics Data System (ADS)

Kanno, Isaku

2018-04-01

In recent years, piezoelectric microelectromechanical systems (MEMS) have attracted attention as next-generation functional microdevices. Typical applications of piezoelectric MEMS are micropumps for inkjet heads or micro-gyrosensors, which are composed of piezoelectric Pb(Zr,Ti)O3 (PZT) thin films and have already been commercialized. In addition, piezoelectric vibration energy harvesters (PVEHs), which are regarded as one of the key devices for Internet of Things (IoT)-related technologies, are promising future applications of piezoelectric MEMS. Significant features of piezoelectric MEMS are their simple structure and high energy conversion efficiency between mechanical and electrical domains even on the microscale. The device performance strongly depends on the function of the piezoelectric thin films, especially on their transverse piezoelectric properties, indicating that the deposition of high-quality piezoelectric thin films is a crucial technology for piezoelectric MEMS. On the other hand, although the difficulty in measuring the precise piezoelectric coefficients of thin films is a serious obstacle in the research and development of piezoelectric thin films, a simple unimorph cantilever measurement method has been proposed to obtain precise values of the direct or converse transverse piezoelectric coefficient of thin films, and recently this method has become to be the standardized testing method. In this article, I will introduce fundamental technologies of piezoelectric thin films and related microdevices, especially focusing on the deposition of PZT thin films and evaluation methods for their transverse piezoelectric properties.

Triz in Mems

NASA Astrophysics Data System (ADS)

Apte, Prakash R.

1999-11-01

TRIZ is a Russian abbreviation. Genrich Altshuller developed it fifty years ago in the former Soviet Union. He examined thousands of inventions made in different technological systems and formulated a 'Theory of Inventive problem solving' (TRIZ). Altshuller's research of over fifty years on Creativity and Inventive Problem Solving has led to many different classifications, methods and tools of invention. Some of these are, Contradictions table, Level of inventions, Patterns in evolution of technological systems, ARIZ-Algorithm for Inventive Problem Solving, Diagnostic problem solving and Anticipatory Failure Determination. MEMS research consists of conceptual design, process technology and including of various Mechanical, ELectrical, Thermal, Magnetic, Acoustic and other effects. MEMS system s are now rapidly growing in complexity. Each system will thus follow one or more 'patterns of evolution' as given by Altshuller. This paper attempts to indicate how various TRIZ tools can be used in MEMS research activities.

Impact of Reflow on the Output Characteristics of Piezoelectric Microelectromechanical System Devices

NASA Astrophysics Data System (ADS)

Nogami, Hirofumi; Kobayashi, Takeshi; Okada, Hironao; Masuda, Takashi; Maeda, Ryutaro; Itoh, Toshihiro

2012-09-01

An animal health monitoring system and a wireless sensor node aimed at preventing the spread of animal-transmitted diseases and improving pastoral efficiency which are especially suitable for chickens, were developed. The sensor node uses a piezoelectric microelectromechanical system (MEMS) device and an event-driven system that is activated by the movements of a chicken. The piezoelectric MEMS device has two functions: a) it measures the activity of a chicken and b) switches the micro-control unit (MCU) of the wireless sensor node from the sleep mode. The piezoelectric MEMS device is required to produce high output voltages when the chicken moves. However, after the piezoelectric MEMS device was reflowed to the wireless sensor node, the output voltages of the piezoelectric MEMS device decreased. The main reason for this might be the loss of residual polarization, which is affected by the thermal load during the reflow process. After the reflow process, we were not able to apply a voltage to the piezoelectric MEMS device; thus, the piezoelectric output voltage was not increased by repoling the piezoelectric MEMS device. To address the thermal load of the reflow process, we established a thermal poling treatment, which achieves a higher temperature than the reflow process. We found that on increasing the thermal poling temperature, the piezoelectric output voltages did not decreased low significantly. Thus, we considered that a thermal poling temperature higher than that of the reflow process prevents the piezoelectric output voltage reduction caused by the thermal load.

Investigation into Contact Resistance And Damage of Metal Contacts Used in RF-MEMS Switches

DTIC Science & Technology

2009-09-01

mechanically cycled by a piezo- electric transducer ( PZT ). The resistance through the simulated switch was measured using a four-wire measurement technique...research, including a brief overview of contact theory. Then chapter 3 gives an overview of engi- 13 V I PZT Sample Mount Cantilever Lower Contact...as described in [3, 118]. The measurement of surface texture and 4These figures were published in Materials Selection in Mechanical Design, Michael F

Gain-Scheduled Complementary Filter Design for a MEMS Based Attitude and Heading Reference System

PubMed Central

Yoo, Tae Suk; Hong, Sung Kyung; Yoon, Hyok Min; Park, Sungsu

2011-01-01

This paper describes a robust and simple algorithm for an attitude and heading reference system (AHRS) based on low-cost MEMS inertial and magnetic sensors. The proposed approach relies on a gain-scheduled complementary filter, augmented by an acceleration-based switching architecture to yield robust performance, even when the vehicle is subject to strong accelerations. Experimental results are provided for a road captive test during which the vehicle dynamics are in high-acceleration mode and the performance of the proposed filter is evaluated against the output from a conventional linear complementary filter. PMID:22163824

Advanced Sensor and Packaging Technologies for Intelligent Adaptive Engine Controls (Preprint)

DTIC Science & Technology

2013-05-01

combination of micro-electromechanical systems (MEMS) sensor technology, novel ceramic materials, high - temperature electronics, and advanced harsh...with simultaneous pressure measurements up to 1,000 psi. The combination of a high - temperature , high -pressure-ratio compressor system, and adaptive...combination of micro-electromechanical systems (MEMS) sensor technology, novel ceramic materials, high temperature electronics, and advanced harsh

Initial animal studies of a wireless, batteryless, MEMS implant for cardiovascular applications.

PubMed

Najafi, Nader; Ludomirsky, Achiau

2004-03-01

This paper reports the results of the initial animal studies of a wireless, batteryless, implantable pressure sensor using microelectromechanical systems (MEMS) technology. The animal studies were acute and proved the functional feasibility of using MEMS technology for wireless bio sensing. The results are very encouraging and surpassed the majority of the application's requirements, including high sampling speed and high resolution. Based on the lessons learned, second generation wireless sensors are being developed that will provide total system solution.

MEMS: Enabled Drug Delivery Systems.

PubMed

Cobo, Angelica; Sheybani, Roya; Meng, Ellis

2015-05-01

Drug delivery systems play a crucial role in the treatment and management of medical conditions. Microelectromechanical systems (MEMS) technologies have allowed the development of advanced miniaturized devices for medical and biological applications. This Review presents the use of MEMS technologies to produce drug delivery devices detailing the delivery mechanisms, device formats employed, and various biomedical applications. The integration of dosing control systems, examples of commercially available microtechnology-enabled drug delivery devices, remaining challenges, and future outlook are also discussed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

European MEMS foundries

NASA Astrophysics Data System (ADS)

Salomon, Patric R.

2003-01-01

According to the latest release of the NEXUS market study, the market for MEMS or Microsystems Technology (MST) is predicted to grow to $68B by the year 2005, with systems containing these components generating even higher revenues and growth. The latest advances in MST/MEMS technology have enabled the design of a new generation of microsystems that are smaller, cheaper, more reliable, and consume less power. These integrated systems bring together numerous analog/mixed signal microelectronics blocks and MEMS functions on a single chip or on two or more chips assembled within an integrated package. In spite of all these advances in technology and manufacturing, a system manufacturer either faces a substantial up-front R&D investment to create his own infrastructure and expertise, or he can use design and foundry services to get the initial product into the marketplace fast and with an affordable investment. Once he has a viable product, he can still think about his own manufacturing efforts and investments to obtain an optimized high volume manufacturing for the specific product. One of the barriers to successful exploitation of MEMS/MST technology has been the lack of access to industrial foundries capable of producing certified microsystems devices in commercial quantities, including packaging and test. This paper discusses Multi-project wafer (MPW) runs, requirements for foundries and gives some examples of foundry business models. Furthermore, this paper will give an overview on MST/MEMS services that are available in Europe, including pure commercial activities, European project activities (e.g. Europractice), and some academic services.

MEMS device for spacecraft thermal control applications

NASA Technical Reports Server (NTRS)

Swanson, Theordore D. (Inventor)

2003-01-01

A micro-electromechanical device that comprises miniaturized mechanical louvers, referred to as Micro Electro-Mechanical Systems (MEMS) louvers are employed to achieve a thermal control function for spacecraft and instruments. The MEMS louvers are another form of a variable emittance control coating and employ micro-electromechanical technology. In a function similar to traditional, macroscopic thermal louvers, the MEMS louvers of the present invention change the emissivity of a surface. With the MEMS louvers, as with the traditional macroscopic louvers, a mechanical vane or window is opened and closed to allow an alterable radiative view to space.

Surface chemistry and tribology of MEMS.

PubMed

Maboudian, Roya; Carraro, Carlo

2004-01-01

The microscopic length scale and high surface-to-volume ratio, characteristic of microelectro-mechanical systems (MEMS), dictate that surface properties are of paramount importance. This review deals with the effects of surface chemical treatments on tribological properties (adhesion, friction, and wear) of MEMS devices. After a brief review of materials and processes that are utilized in MEMS technology, the relevant tribological and chemical issues are discussed. Various MEMS microinstruments are discussed, which are commonly employed to perform adhesion, friction, and wear measurements. The effects of different surface treatments on the reported tribological properties are discussed.

High-performance hybrid complementary logic inverter through monolithic integration of a MEMS switch and an oxide TFT.

PubMed

Song, Yong-Ha; Ahn, Sang-Joon Kenny; Kim, Min-Wu; Lee, Jeong-Oen; Hwang, Chi-Sun; Pi, Jae-Eun; Ko, Seung-Deok; Choi, Kwang-Wook; Park, Sang-Hee Ko; Yoon, Jun-Bo

2015-03-25

A hybrid complementary logic inverter consisting of a microelectromechanical system switch as a promising alternative for the p-type oxide thin film transistor (TFT) and an n-type oxide TFT is presented for ultralow power integrated circuits. These heterogeneous microdevices are monolithically integrated. The resulting logic device shows a distinctive voltage transfer characteristic curve, very low static leakage, zero-short circuit current, and exceedingly high voltage gain. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Design and Fabrication of a Strain-Powered Microelectromechanical System (MEMS) Switch

DTIC Science & Technology

2014-09-01

release showing uniform folding upwards; the top edge appears to be anchored to the substrate, which necessitated a mask rewrite after reducing...underdeveloped resist causing the switch to be anchored (left), thin-film shearing at the contact edge (right), and thin- film edge anchoring (right). Geometry...a “hip” joint and an “ ankle ” joint—while a center hinge was designed to fold down at a “knee” joint and make electrical contact with an electrical

Development of a wireless MEMS multifunction sensor system and field demonstration of embedded sensors for monitoring concrete pavements : tech transfer summary.

DOT National Transportation Integrated Search

2016-08-01

Micro-electromechanical sensors and systems- (MEMS)-based and : wireless-based smart-sensing technologies have, until now, rarely : been used for monitoring pavement response in the field, and the : requirements for using such smart sensing technolog...

Towards a biomimetic gyroscope inspired by the fly's haltere using microelectromechanical systems technology

PubMed Central

Droogendijk, H.; Brookhuis, R. A.; de Boer, M. J.; Sanders, R. G. P.; Krijnen, G. J. M.

2014-01-01

Flies use so-called halteres to sense body rotation based on Coriolis forces for supporting equilibrium reflexes. Inspired by these halteres, a biomimetic gimbal-suspended gyroscope has been developed using microelectromechanical systems (MEMS) technology. Design rules for this type of gyroscope are derived, in which the haltere-inspired MEMS gyroscope is geared towards a large measurement bandwidth and a fast response, rather than towards a high responsivity. Measurements for the biomimetic gyroscope indicate a (drive mode) resonance frequency of about 550 Hz and a damping ratio of 0.9. Further, the theoretical performance of the fly's gyroscopic system and the developed MEMS haltere-based gyroscope is assessed and the potential of this MEMS gyroscope is discussed. PMID:25100317

Microelectromechanical Systems

NASA Technical Reports Server (NTRS)

Gabriel, Kaigham J.

1995-01-01

Micro-electromechanical systems (MEMS) is an enabling technology that merges computation and communication with sensing and actuation to change the way people and machines interact with the physical world. MEMS is a manufacturing technology that will impact widespread applications including: miniature inertial measurement measurement units for competent munitions and personal navigation; distributed unattended sensors; mass data storage devices; miniature analytical instruments; embedded pressure sensors; non-invasive biomedical sensors; fiber-optics components and networks; distributed aerodynamic control; and on-demand structural strength. The long term goal of ARPA's MEMS program is to merge information processing with sensing and actuation to realize new systems and strategies for both perceiving and controlling systems, processes, and the environment. The MEMS program has three major thrusts: advanced devices and processes, system design, and infrastructure.

MEMS-based thermoelectric infrared sensors: A review

NASA Astrophysics Data System (ADS)

Xu, Dehui; Wang, Yuelin; Xiong, Bin; Li, Tie

2017-12-01

In the past decade, micro-electromechanical systems (MEMS)-based thermoelectric infrared (IR) sensors have received considerable attention because of the advances in micromachining technology. This paper presents a review of MEMS-based thermoelectric IR sensors. The first part describes the physics of the device and discusses the figures of merit. The second part discusses the sensing materials, thermal isolation microstructures, absorber designs, and packaging methods for these sensors and provides examples. Moreover, the status of sensor implementation technology is examined from a historical perspective by presenting findings from the early years to the most recent findings.

EDITORIAL: Selected papers from the 10th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2010) Selected papers from the 10th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2010)

NASA Astrophysics Data System (ADS)

Reynaerts, Dominiek; Vullers, Ruud

2011-10-01

This special section of Journal of Micromechanics and Microengineering features papers selected from the 10th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2010). The workshop was organized in Leuven, Belgium from 30 November to 3 December 2010 by Katholieke Universiteit Leuven and the imec/Holst Centre. This was a special PowerMEMS Workshop, for several reasons. First of all, we celebrated the 10th anniversary of the workshop: the first PowerMEMS meeting was organized in Sendai, Japan in 2000. None of the organizers or participants of this first meeting could have predicted the impact of the workshop over the next decade. The second reason was that, for the first time, the conference organization spanned two countries: Belgium and the Netherlands. Thanks to the advances in information technology, teams from Katholieke Universiteit Leuven (Belgium) and the imec/Holst Centre in Eindhoven (the Netherlands) have been able to work together seamlessly as one team. The objective of the PowerMEMS Workshop is to stimulate innovation in micro and nanotechnology for power generation and energy conversion applications. Its scope ranges from integrated microelectromechanical systems (MEMS) for power generation, dissipation, harvesting, and management, to novel nanostructures and materials for energy-related applications. True to the objective of the PowerMEMSWorkshop, the 2010 technical program covered a broad range of energy related research, ranging from the nanometer to the millimeter scale, discussed in 5 invited and 52 oral presentations, and 112 posters. This special section includes 14 papers covering vibration energy harvesters, thermal applications and micro power systems. Finally, we wish to express sincere appreciation to the members of the International Steering Committee, the Technical Program Committee and last but not least the Local Organizing Committee. This special issue was edited in collaboration with the staff of IOP Publishing. PowerMEMS 2010 contents Harvesting energy from airflow with a michromachined piezoelectric harvester inside a Helmholtz resonator S P Matova, R Elfrink, R J M Vullers and R van Schaijk Analysis and characterization of triangular electrode structures for electrostatic energy harvestingDaniel Hoffmann, Bernd Folkmer and Yiannos Manoli A smart and self-sufficient frequency tunable vibration energy harvesterC Eichhorn, R Tchagsim, N Wilhelm and P Woias Power output enhancement of a vibration-driven electret generator for wireless sensor applicationsTatsuakira Masaki, Kenji Sakurai, Toru Yokoyama, Masayo Ikuta, Hiroshi Sameshima, Masashi Doi, Tomonori Seki and Masatoshi Oba Harvesting traffic-induced vibrations for structural health monitoring of bridgesT V Galchev, J McCullagh, R L Peterson and K Najafi Dispenser-printed planar thick-film thermoelectric energy generatorsA Chen, D Madan, P K Wright and J W Evans Silicon nanowire arrays as thermoelectric material for a power microgeneratorD Dávila, A Tarancón, M Fernández-Regúlez, C Calaza, M Salleras, A San Paulo and L Fonseca A micro thermal switch with a stiffness-enhanced thermal isolation structureTakashiro Tsukamoto, Masayoshi Esashi and Shuji Tanaka A dielectric liquid contact thermal switch with electrowetting actuationA R McLanahan, C D Richards and R F Richards A self-regulating valve for single-phase liquid cooling of microelectronicsRadu Donose, Michaël De Volder, Jan Peirs and Dominiek Reynaerts A MEMS-enabled 3D zinc-air microbattery with improved discharge characteristics based on a multilayer metallic substructureA Armutlulu, Y Fang, S H Kim, C H Ji, S A Bidstrup Allen and M G Allen Design, fabrication and testing of an air-breathing micro direct methanol fuel cell with compound anode flow fieldLuwen Wang, Yufeng Zhang, Youran Zhao, Zijiang An, Zhiping Zhou and Xiaowei Liu A shadow-mask evaporated pyroMEMS igniterD A de Koninck, D Briand and N F de Rooij Aerodynamic journal bearing with a flexible, damped support operating at 7.2 million DNTobias Waumans, Jan Peirs, Farid Al-Bender and Dominiek Reynaerts Thermoelectric energy harvester on the heated human machineVladimir Leonov

Investigation of improved designs for rotational micromirrors using multiuser MEMS processes

NASA Astrophysics Data System (ADS)

Lin, Julianna E.; Michael, Feras S. J.; Kirk, Andrew G.

2001-04-01

In recent years, the design of rotational micromirrors for use in optical cross connects has received much attention. Although several companies have already produced and marketed a number of torsional mirror devices, more work is still needed to determine how these mirrors can be integrated into optical systems to form compact optical switches. However, recently several commercial MEMS foundry services have become available. Thus, due to the low cost of these prototyping services, new devices can be fabricated in short amounts of time and the designs adapted to meet the needs of different applications. The purpose of this work is to investigate the fabrication of new micromirror designs using the Multi-User MEMS Processes (MUMPs) foundry service available from Cronos Integrated Microsystems, located in North Carolina, USA). Several sets of mirror designs were submitted for fabrication and the resulting structures characterized using a phase-shifting Mirau interferometer. The results of these devices are presented.

Mechanical behavior simulation of MEMS-based cantilever beam using COMSOL multiphysics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Acheli, A., E-mail: aacheli@cdta.dz; Serhane, R.

This paper presents the studies of mechanical behavior of MEMS cantilever beam made of poly-silicon material, using the coupling of three application modes (plane strain, electrostatics and the moving mesh) of COMSOL Multi-physics software. The cantilevers playing a key role in Micro Electro-Mechanical Systems (MEMS) devices (switches, resonators, etc) working under potential shock. This is why they require actuation under predetermined conditions, such as electrostatic force or inertial force. In this paper, we present mechanical behavior of a cantilever actuated by an electrostatic force. In addition to the simplification of calculations, the weight of the cantilever was not taken intomore » account. Different parameters like beam displacement, electrostatics force and stress over the beam have been calculated by finite element method after having defining the geometry, the material of the cantilever model (fixed at one of ends but is free to move otherwise) and his operational space.« less

NANOSPACE-1: the Impacts of the First Swedish Nanosatellite on Spacecraft Architecture and Design

NASA Astrophysics Data System (ADS)

Bruhn, F.; Köhler, J.; Stenmark, L.

2002-01-01

NanoSpace-1 (NS-1), due to be launched in late 2003 or early 2004 will test highly advanced Micro Systems Technology (MST) for space applications. These devices are highly miniaturized and optimized complete systems in the sense that all parts of the system are processed with MST and integrated as Multifunctional Microsystems (MMS). The very high level of miniaturization and multifunctionallity in the MMS, will enable easier access to space for nanosatellites to perform better scientific research. This new class of high performing small satellites will open areas for research that before only could be done with much larger and costly satellites. Many institutions, universities, and small countries will benefit greatly as that nanosatellites become more capable per mass unit and volume unit than other spacecraft. These new MMS/MST satellites will provide the ground for a better and less expensive exploration of space. NS-1 will be the first high-performing nanosatellite by using MST/MMS to many subsystems and modules. The whole spacecraft will be built around MMS and will include multifunctional 3D-Multi Chip Modules (3D-MCM), a 3D thin film solar sensor, thin film coating for passive thermal control, variable emittance panels, microwave MEMS patch antennas, micromechanical thermal switches, thin film solar cells with record high efficiency and finally silicon as multifunctional active structure elements. The complete spacecraft will weigh about 7 kg and have dimensions of 32x32x15 cm. The overall mission for NS-1 is to test the new technologies mentioned above, and to collect experiences in the field of MMS architecture. However, new technologies in itself will not take us to a new generation spacecraft. Deeply integrated within the structure of the NanoSpace program are new system designs and multifunctional systems thinking. Distributed and autonomous subsystems are very important when incorporating new technologies with high redundancy. Autonomous systems also reduce the complexity of the overall spacecraft design since many functions can be placed in multifunctional multichip modules. This implies an increase of the complexity at the spacecraft subsystem level. NanoSpace-1 will test several new autonomous, distributed, and miniaturized multifunctional systems, including large memories modules, house keeping modules, RF- MEMS, and power conditioning modules. The MMS concept comprises several features, for instance, all 3D-multi chip modules are part of the spacecraft structure itself. The use of 3D-MCM modules as a large part of the spacecraft hull is a direct application of MMS thinking; the modules are load taking structure elements, and also contain many subsystems of the spacecraft. The MMS thinking is illustrated by the RF-MEMS 3D-MCM module. All other modules will be further presented in the paper. The RF-MEMS module comprises micro strips, patch-antennas, solid state power amplifiers, thermal control, micromechanical switches, power conditioning, radiation shields, and command interfaces. The size of the RF-module is 68x68x5 mm and has a weight of less than 70g. The module is designed to handle different frequencies, only by changing the top wafers and the mixer chip. MST and MMS integrated modules pose at least two major challenges compared to conventional technology. First, the processes cannot be changed half way to the product. Any substantial change in the process will almost certainly require a complete redesign of the whole system. Secondly, qualification and product assurance becomes more important since the processes in MMS tend to be long and complicated. The Ångström Space Technology Centre (ÅSTC) is a center for development of Micro Systems Technologies (MST) for Space Applications at the department of Materials Science at Uppsala University in Sweden. The center is now taking the next step in the ongoing Nanosatellite program, called the NanoSpace program. Backed by funding from the Swedish National Space Board (SNSB), the European Space Agency (ESA), and the European Commission (EC), the ÅSTC will begin developing nanosatellites to demonstrate the next generation spacecraft. The Nanosatellite program is built around a launch every 2nd year to test, verify and qualify new MST technologies for space. The Nanosatellite effort is a solid and well founded program with a backbone of technology research and Multifunctional Microsystems (MMS) thinking.

Nano- and micro-electromechanical switch dynamics

NASA Astrophysics Data System (ADS)

Pulskamp, Jeffrey S.; Proie, Robert M.; Polcawich, Ronald G.

2013-01-01

This paper reports theoretical analysis and experimental results on the dynamics of piezoelectric MEMS mechanical logic relays. The multiple degree of freedom analytical model, based on modal decomposition, utilizes modal parameters obtained from finite element analysis and an analytical model of piezoelectric actuation. The model accounts for exact device geometry, damping, drive waveform variables, and high electric field piezoelectric nonlinearity. The piezoelectrically excited modal force is calculated directly and provides insight into design optimization for switching speed. The model accurately predicts the propagation delay dependence on actuation voltage of mechanically distinct relay designs. The model explains the observed discrepancies in switching speed of these devices relative to single degree of freedom switching speed models and suggests the strong potential for improved switching speed performance in relays designed for mechanical logic and RF circuits through the exploitation of higher order vibrational modes.

Enabling MEMS technologies for communications systems

NASA Astrophysics Data System (ADS)

Lubecke, Victor M.; Barber, Bradley P.; Arney, Susanne

2001-11-01

Modern communications demands have been steadily growing not only in size, but sophistication. Phone calls over copper wires have evolved into high definition video conferencing over optical fibers, and wireless internet browsing. The technology used to meet these demands is under constant pressure to provide increased capacity, speed, and efficiency, all with reduced size and cost. Various MEMS technologies have shown great promise for meeting these challenges by extending the performance of conventional circuitry and introducing radical new systems approaches. A variety of strategic MEMS structures including various cost-effective free-space optics and high-Q RF components are described, along with related practical implementation issues. These components are rapidly becoming essential for enabling the development of progressive new communications systems technologies including all-optical networks, and low cost multi-system wireless terminals and basestations.

Alternative Dielectric Films for rf MEMS Capacitive Switches Deposited using Atomic Layer Deposited Al2O3/ZnO Alloys

DTIC Science & Technology

2006-07-02

A s c c s r t h s l © K 1 b c A a e t s C t o 0 d Sensors and Actuators A 135 (2007) 262–272 Alternative dielectric films for rf MEMS capacitive...Zn concentrations in the alloy films , which was lower than expected. Atomic force microscopy images evealed an average surface roughness of 0.27 nm...that was independent of deposition temperature and film composition. The dielectric constants of he Al2O3/ZnO ALD alloys films were calculated to be

MEMS startups: disruptive technology and business do's and don'ts

NASA Astrophysics Data System (ADS)

Bryzek, Janusz

2005-02-01

This paper characterizes factors that affect the probability of success for new startups. These guidelines are derived primarily from Venture Capital industry experience in funding disruptive technology companies. It follows with an overview of Silicon Valley MEMS and MOEMS startups and provides with a summary of Do"s and Don"ts for entrepreneurs.

Noise, fluctuation, and HADAMARD-transform spectrometry

NASA Astrophysics Data System (ADS)

Nitzsche, Guenter; Riesenberg, Rainer

2003-05-01

The HADAMARD principle is known in optics as a multiplex technique. It describes the mode with the most advantageous increase of the signal-to-noise ratio (SNR) in terms of scanning (Fellget advantage). The maximum increase of SNR, we call it gain, is (n+1)/(2On), where n is the number of multiplexing. It is valid in the case of pure detector noise. The multiplex encoding Hadamard pattern in case of n = 7 is 1110100, whereby 1 stands for a switched on channel performed by a field selector. The signals of all (switched on) channels are detected by a single detector. n measurement steps with a cyclic change of the pattern is necessary to perform the Hadamard transformation and to get the result of each individual channel. In case of n = 7 the theoretical gain is 1.51. For all possible multiplex pattern (1100000, 1110000 and so on) the gain is theoretically investigated. A multiplexing advantage (gain > 1) is reached only by the Hadamard pattern, the inverse Hadamard pattern and for (0111111)-pattern (gain=1.08). Most of the multiplex pattern are disadvantageous. The reason for maximum gain of the HADAMARD transformation is analysed theoretically. Signal fluctuations during the measurement caused by fluctuations of the illumination or by the object under test, reduce the multiplex gain, too. So the limits for realizing a gain are estimated theoretically. Essential is the transformation procedure and its influence on the error propagation. The results could be verified by experiments with array spectrometeres. Requirements are derived by numerical simulation concerning the stability of the signals to be multiplexed. It is simulated the needed stability of the signals with increasing order of multiplexing. So the increase of the multiplex gain is limited by signal fluctuations. A realized 96 channel spectral reader is presented as a modern application of an optical multiplexing arrangement. ! M. Harvid, N. J. A. Sloane, Hadamard Transform Optics, Academic Press, 1979 ! R.A. De Verse, R.M. Hammaker, W. G. Fately, J.A.Graham, J.D.Tate, "Spectrometry and imaging using a digital micromirror array" American Laboratory, Vol. 30, 21, pp. 112-120, 1998 ! R. Riesenberg, A. Wuttig, B. Harnisch, "Optical MEMS Technology for Multiplexing in High-End Micro-Scpectrometers", Proc. SPIE 4928, 6-14, 2002 ! A. Wuttig, R. Riesenberg, "Hyperspectral imager with a facile MEMS", Proc. SPIE 4881A, 2002, to be published ! R. Riesenberg, G. Nitzsche, W. Voigt, 'HADAMARD Encoding and other optical Multiplexing', VDI-Berichte 1694, pp. 345-350, 2002 ! A. Wuttig, R. Riesenberg, G. Nitzsche, "Subpixel Analysis of Double Array Grating Spectrometer", Proc. SPIE 4480, pp. 334-344, 2002 ! A. Wuttig, R. Riesenberg, G. Nitzsche, "Integral Field and Multi Object Spectrometry with MEMS", Proc. SPIE 4480, pp. 367-376, 2002 ! R. Riesenberg, G. Nitzsche, A. Wuttig, B. Harnisch, "Micro Spectrometer and MEMS for Space" in "Smaller Satellites: Bigger Business?", edited by M. Rycroft, N. Crosby, Kluwer Academic Publisher, pp. 403-406, 2002 ! R. Riesenberg, A. Wuttig, "Optical sensors with MEMS, slit masks and micromechanical devices", Proc. SPIE 4561, pp. 315-322, 2001 ! R. Riesenberg, "MicroMechanical Slit Positioning System as a transmissive spatial Light Modulator", Proc. SPIE 4457, pp.197-203, 2001 ! R. Riesenberg, J. Lonschinski, "HADAMARD-Minispectrometer made by a Micro Device", Proc. "3rd Round Table on Micro/NanoTechnologies for Space", ESTEC, Noordwijk, The Netherlands, pp. 291 - 297, 2000 ! R. Riesenberg, U. Dillner, "HADAMARD Imaging Spectrometers", Proc. SPIE 3753, pp. 203-213, 1999 ! R. Riesenberg, Th. Seifert, "Design of spatial Light Modulator Microdevices - Micro Slit Arrays", Proc. SPIE 3680, Part One, pp. 406-414, 1999 ! R. Riesenberg, W. Voigt, J. Schoneich, "Compact Spectrometers made by Micro System Technology", Sensor 97, Proc. Vol. 2, pp. 145-150,1997

A Generalized Polynomial Chaos-Based Approach to Analyze the Impacts of Process Deviations on MEMS Beams.

PubMed

Gao, Lili; Zhou, Zai-Fa; Huang, Qing-An

2017-11-08

A microstructure beam is one of the fundamental elements in MEMS devices like cantilever sensors, RF/optical switches, varactors, resonators, etc. It is still difficult to precisely predict the performance of MEMS beams with the current available simulators due to the inevitable process deviations. Feasible numerical methods are required and can be used to improve the yield and profits of the MEMS devices. In this work, process deviations are considered to be stochastic variables, and a newly-developed numerical method, i.e., generalized polynomial chaos (GPC), is applied for the simulation of the MEMS beam. The doubly-clamped polybeam has been utilized to verify the accuracy of GPC, compared with our Monte Carlo (MC) approaches. Performance predictions have been made on the residual stress by achieving its distributions in GaAs Monolithic Microwave Integrated Circuit (MMIC)-based MEMS beams. The results show that errors are within 1% for the results of GPC approximations compared with the MC simulations. Appropriate choices of the 4-order GPC expansions with orthogonal terms have also succeeded in reducing the MC simulation labor. The mean value of the residual stress, concluded from experimental tests, shares an error about 1.1% with that of the 4-order GPC method. It takes a probability around 54.3% for the 4-order GPC approximation to attain the mean test value of the residual stress. The corresponding yield occupies over 90 percent around the mean within the twofold standard deviations.

A Generalized Polynomial Chaos-Based Approach to Analyze the Impacts of Process Deviations on MEMS Beams

PubMed Central

Gao, Lili

2017-01-01

A microstructure beam is one of the fundamental elements in MEMS devices like cantilever sensors, RF/optical switches, varactors, resonators, etc. It is still difficult to precisely predict the performance of MEMS beams with the current available simulators due to the inevitable process deviations. Feasible numerical methods are required and can be used to improve the yield and profits of the MEMS devices. In this work, process deviations are considered to be stochastic variables, and a newly-developed numerical method, i.e., generalized polynomial chaos (GPC), is applied for the simulation of the MEMS beam. The doubly-clamped polybeam has been utilized to verify the accuracy of GPC, compared with our Monte Carlo (MC) approaches. Performance predictions have been made on the residual stress by achieving its distributions in GaAs Monolithic Microwave Integrated Circuit (MMIC)-based MEMS beams. The results show that errors are within 1% for the results of GPC approximations compared with the MC simulations. Appropriate choices of the 4-order GPC expansions with orthogonal terms have also succeeded in reducing the MC simulation labor. The mean value of the residual stress, concluded from experimental tests, shares an error about 1.1% with that of the 4-order GPC method. It takes a probability around 54.3% for the 4-order GPC approximation to attain the mean test value of the residual stress. The corresponding yield occupies over 90 percent around the mean within the twofold standard deviations. PMID:29117096

Laser-assisted advanced assembly for MEMS fabrication

NASA Astrophysics Data System (ADS)

Atanasov, Yuriy Andreev

Micro Electro-Mechanical Systems (MEMS) are currently fabricated using methods originally designed for manufacturing semiconductor devices, using minimum if any assembly at all. The inherited limitations of this approach narrow the materials that can be employed and reduce the design complexity, imposing limitations on MEMS functionality. The proposed Laser-Assisted Advanced Assembly (LA3) method solves these problems by first fabricating components followed by assembly of a MEMS device. Components are micro-machined using a laser or by photolithography followed by wet/dry etching out of any material available in a thin sheet form. A wide range of materials can be utilized, including biocompatible metals, ceramics, polymers, composites, semiconductors, and materials with special properties such as memory shape alloys, thermoelectric, ferromagnetic, piezoelectric, and more. The approach proposed allows enhancing the structural and mechanical properties of the starting materials through heat treatment, tribological coatings, surface modifications, bio-functionalization, and more, a limited, even unavailable possibility with existing methods. Components are transferred to the substrate for assembly using the thermo-mechanical Selective Laser Assisted Die Transfer (tmSLADT) mechanism for microchips assembly, already demonstrated by our team. Therefore, the mechanical and electronic part of the MEMS can be fabricated using the same equipment/method. The viability of the Laser-Assisted Advanced Assembly technique for MEMS is demonstrated by fabricating magnetic switches for embedding in a conductive carbon-fiber metamaterial for use in an Electromagnetic-Responsive Mobile Cyber-Physical System (E-RMCPS), which is expected to improve the wireless communication system efficiency within a battery-powered device.

EDITORIAL: The Fourth International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2004)

NASA Astrophysics Data System (ADS)

Tanaka, Shuji; Toriyama, Toshiyuki

2005-09-01

This special issue of the Journal of Micromechanics and Microengineering features papers selected from the Fourth International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2004). The workshop was held in Kyoto, Japan, on 28-30 November 2004, by The Ritsumeikan Research Institute of Micro System Technology in cooperation with The Global Emerging Technology Institute, The Institute of Electrical Engineers of Japan, The Sensors and Micromachines Society, The Micromachine Center and The Kyoto Nanotech Cluster. Power MEMS is one of the newest categories of MEMS, which encompasses microdevices and microsystems for power generation, energy conversion and propulsion. The first concept of power MEMS was proposed in the late 1990s by Epstein's group at the Massachusetts Institute of Technology, where they continue to study MEMS-based gas turbine generators. Since then, the research and development of power MEMS have been promoted by the need for compact power sources with high energy and power density. Since its inception, power MEMS has expanded to include not only various MEMS-based power generators but also small energy machines and microdevices for macro power generators. At the last workshop, various devices and systems, such as portable fuel cells and their peripherals, micro and small turbo machinery, energy harvesting microdevices, and microthrusters, were presented. Their power levels vary from ten nanowatts to hundreds of watts, spanning ten orders of magnitude. The first PowerMEMS workshop was held in 2000 in Sendai, Japan, and consisted of only seven invited presentations. The workshop has grown since then, and in 2004 there were 5 invited, 20 oral and 29 poster presentations. From the 54 papers in the proceedings, 12 papers have been selected for this special issue. I would like to express my appreciation to the members of the Organizing Committee and Technical Program Committee. This special issue was edited in collaboration with Professor Toshiyuki Toriyama (Ritsumeikan University), Co-chair of the Technical Program Committee, and the Institute of Physics Publishing staff.

In situ MEMS testing: correlation of high-resolution X-ray diffraction with mechanical experiments and finite element analysis

NASA Astrophysics Data System (ADS)

Schifferle, Andreas; Dommann, Alex; Neels, Antonia

2017-12-01

New methods are needed in microsystems technology for evaluating microelectromechanical systems (MEMS) because of their reduced size. The assessment and characterization of mechanical and structural relations of MEMS are essential to assure the long-term functioning of devices, and have a significant impact on design and fabrication.

Selected papers from the 12th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2012) (Atlanta, GA, USA, 2-5 December 2012)

NASA Astrophysics Data System (ADS)

Allen, Mark G.; Lang, Jeffrey

2013-11-01

Welcome to this special section of the Journal of Micromechanics and Microengineering (JMM). This section, co-edited by myself and by Professor Jeffrey Lang of the Massachusetts Institute of Technology, contains expanded versions of selected papers presented at the Power MEMS meeting held in Atlanta, GA, USA, in December of 2012. Professor Lang and I had the privilege of co-chairing Power MEMS 2012, the 12th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications. The scope of the PowerMEMS series of workshops ranges from basic principles, to materials and fabrication, to devices and systems, to applications. The many applications of power MEMS (microelectromehcanical systems) range from MEMS-enabled energy harvesting, storage, conversion and conditioning, to integrated systems that manage these processes. Why is the power MEMS field growing in importance? Smaller-scale power and power supplies (microwatts to tens of watts) are gaining in prominence due to many factors, including the ubiquity of low power portable electronic equipment and the proliferation of wireless sensor nodes that require extraction of energy from their embedding environment in order to function. MEMS manufacturing methods can be utilized to improve the performance of traditional power supply elements, such as allowing batteries to charge faster or shrinking the physical size of passive elements in small-scale power supplies. MEMS technologies can be used to fabricate energy harvesters that extract energy from an embedding environment to power wireless sensor nodes, in-body medical implants and other devices, in which the harvesters are on the small scales that are appropriately matched to the overall size of these microsystems. MEMS can enable the manufacturing of energy storage elements from nontraditional materials by bringing appropriate structure and surface morphology to these materials as well as fabricating the electrical interfaces required for their operation and interconnection. Clearly, the marriage of MEMS technologies and energy conversion is a vital application space; and we are pleased to bring you some of the latest results from that space in this special section. Approximately 130 papers were presented at the Power MEMS 2012 conference. From these, the 20 papers you have before you were selected based on paper quality and topical balance. As you can see, papers representing many of the important areas of power MEMS are included: energy harvesters using multiple transduction schemes; MEMS-based fabrication of compact passive elements (inductors, supercapacitors, transformers); MEMS-enabled power diagnostics; MEMS-based batteries; and low power circuitry adapted to interfacing MEMS-based harvesters to overall systems. All of the papers you will read in this special section comprise substantial expansion from the proceedings articles and were reviewed through JMM's normal reviewing process. Both Professor Lang and I hope that you will share our enthusiasm for the field of power MEMS and that you will find this special section of JMM exciting, interesting and useful.  Sincerely,  Mark G Allen

A review of MEMS micropropulsion technologies for CubeSats and PocketQubes

NASA Astrophysics Data System (ADS)

Silva, Marsil A. C.; Guerrieri, Daduí C.; Cervone, Angelo; Gill, Eberhard

2018-02-01

CubeSats have been extensively used in the past decade as scientific tools, technology demonstrators and for education. Recently, PocketQubes have emerged as an interesting and even smaller alternative to CubeSats. However, both satellite types often lack some key capabilities, such as micropropulsion, in order to further extend the range of applications of these small satellites. This paper reviews the current development status of micropropulsion systems fabricated with MEMS (micro electro-mechanical systems) and silicon technology intended to be used in CubeSat or PocketQube missions and compares different technologies with respect to performance parameters such as thrust, specific impulse, and power as well as in terms of operational complexity. More than 30 different devices are analyzed and divided into 7 main categories according to the working principle. A specific outcome of the research is the identification of the current status of MEMS technologies for micropropulsion including key opportunities and challenges.

Thin Film Transistor Control Circuitry for MEMS Acoustic Transducers

NASA Astrophysics Data System (ADS)

Daugherty, Robin

This work seeks to develop a practical solution for short range ultrasonic communications and produce an integrated array of acoustic transmitters on a flexible substrate. This is done using flexible thin film transistor (TFT) and micro electromechanical systems (MEMS). The goal is to develop a flexible system capable of communicating in the ultrasonic frequency range at a distance of 10-100 meters. This requires a great deal of innovation on the part of the FDC team developing the TFT driving circuitry and the MEMS team adapting the technology for fabrication on a flexible substrate. The technologies required for this research are independently developed. The TFT development is driven primarily by research into flexible displays. The MEMS development is driving by research in biosensors and micro actuators. This project involves the integration of TFT flexible circuit capabilities with MEMS micro actuators in the novel area of flexible acoustic transmitter arrays. This thesis focuses on the design, testing and analysis of the circuit components required for this project.

MEMS applications in space exploration

NASA Astrophysics Data System (ADS)

Tang, William C.

1997-09-01

Space exploration in the coming century will emphasize cost effectiveness and highly focused mission objectives, which will result in frequent multiple missions that broaden the scope of space science and to validate new technologies on a timely basis. MEMS is one of the key enabling technology to create cost-effective, ultra-miniaturized, robust, and functionally focused spacecraft for both robotic and human exploration programs. Examples of MEMS devices at various stages of development include microgyroscope, microseismometer, microhygrometer, quadrupole mass spectrometer, and micropropulsion engine. These devices, when proven successful, will serve as models for developing components and systems for new-millennium spacecraft.

Applications of MEMS for Space Exploration

NASA Astrophysics Data System (ADS)

Tang, William C.

1998-03-01

Space exploration in the coming century will emphasize cost effectiveness and highly focused mission objectives, which will result in frequent multiple missions that broaden the scope of space science and to validate new technologies on a timely basis. Micro Electro Mechanical Systems (MEMS) is one of the key enabling technologies to create cost-effective, ultra-miniaturized, robust, and functionally focused spacecraft for both robotic and human exploration programs. Examples of MEMS devices at various stages of development include microgyroscope, microseismometer, microhygrometer, quadrupole mass spectrometer, and micropropulsion engine. These devices, when proven successful, will serve as models for developing components and systems for new-millennium spacecraft.

EDITORIAL: The 7th International Workshop on Micro and Nanotechnologies for Power Generation and Energy Conversion Applications (PowerMEMS 2007)

NASA Astrophysics Data System (ADS)

Hebling, C.; Woias, P.

2008-10-01

This special issue of Journal of Micromechanics and Microengineering (JMM) contains a selection of papers from the 7th International Workshop on Micro and Nanotechnologies for Power Generation and Energy Conversion (PowerMEMS 2007). The workshop was held in Freiburg, Germany on 27-29 November 2007 under the joint organization of the Fraunhofer Institute for Solar Energy Systems (FhG-ISE), Freiburg and the Department of Microsystems Engineering (IMTEK) of the Albert-Ludwig-University of Freiburg. PowerMEMS 2007 continues a series of workshops initiated in 2000 in Japan to create an annual discussion forum in the emerging field of micro energy technology. With a single exception in 2001, the workshop has continued as an annual meeting ever since, with a continuous increase in the number of presentations and participants. The program of PowerMEMS 2007 was composed of 2 invited talks, 25 oral talks and 61 poster presentations. From these 88 presentations 16 have been selected for this special issue. It was at the end of 1959 when the Caltech physicist Richard Feynman gave his famous lecture entitled 'There Is Plenty of Room at the Bottom' in which he discussed the possibilities of miniaturization for both storage capacity ('Encyclopaedia Britannica on the head of a pin') as well as micro machining ('rearranging the atoms'), although there were absolutely no technological possibilities in sight for an adequate realization of such ideas. Now, nearly 50 years later, we not only have incredible knowledge about the nanoworld, but even more we are now able to generate microelectromechanical devices which, next to their electronic properties, can integrate physical and analytical functions. Today, Feynman might easily have added a second lecture entitled 'There is Plenty of Energy at the Bottom'. Micro energy technology has seen a tremendous rise in MEMS and material sciences and is regarded today as one of their hot topics. Also, there are more and more companies in this field trying to commercialize micro energy harvesting devices, micro thermo-photovoltaics or micro fuel cells in order to make an impact on our daily life. It is interesting to see the remarkable scientific dynamics and innovations in micro energy technology that have been mirrored in the scope of consecutive PowerMEMS workshops. Micro fuel cells, micro combustion systems and heat engines have been on-going topics from the beginning due to their promising power densities and high power levels up to hundreds of watts. At the other end of the power scale micro energy harvesting has entered the stage, with a remarkable growth rate of presentations during the last three workshops, towering over all other topics with 33 presentations at PowerMEMS 2007. Another significant trend is the slow but steady emergence of electronic energy management as a future key technology. As Guest Editors of this special issue we would like to express our appreciation to the members of the Organizing Committee and the Technical Program Committee of PowerMEMS for their on-going efforts. By selecting the research fields mentioned above they formed the PowerMEMS 2007 program as a comprehensive digest of today's micro energy technology that is reflected, along with selected high quality publications, in this special issue of JMM. We hope that this work will stimulate further innovative research in micro energy technology and will help to mark the trail for further progress in this exciting field of MEMS science and technology.

Nano/micro-electro mechanical systems: a patent view

NASA Astrophysics Data System (ADS)

Hu, Guangyuan; Liu, Weishu

2015-12-01

Combining both bibliometrics and citation network analysis, this research evaluates the global development of micro-electro mechanical systems (MEMS) research based on the Derwent Innovations Index database. We found that worldwide, the growth trajectory of MEMS patents demonstrates an approximate S shape, with United States, Japan, China, and Korea leading the global MEMS race. Evidenced by Derwent class codes, the technology structure of global MEMS patents remains steady over time. Yet there does exist a national competitiveness component among the top country players. The latecomer China has become the second most prolific country filing MEMS patents, but its patent quality still lags behind the global average.

Capacitive microelectromechanical switches with dynamic soft-landing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jain, Ankit; Alam, Muhammad Ashraful; Nair, Pradeep R.

2015-10-13

A microelectromechanical system (MEMS)-based electrical switch. The electrical switch includes a moveable electrode, a dielectric layer positioned adjacent the moveable electrode on a first side of the dielectric layer and spaced apart from the moveable electrode when the moveable electrode is in an inactivated position and in contact with the moveable electrode when the moveable electrode is in an activated position, and a substrate attached to the dielectric layer on a second side opposite to the first side, the moveable electrode is configured to brake prior to coming in contact with the dielectric layer when the moveable electrode is switchedmore » between the inactivated state and the activated state.« less

Capacitive microelectromechanical switches with dynamic soft-landing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jain, Ankit; Alam, Muhammad Ashraful; Nair, Pradeep

2017-01-03

A microelectromechanical system (MEMS)-based electrical switch. The electrical switch includes a moveable electrode, a dielectric layer positioned adjacent the moveable electrode on a first side of the dielectric layer and spaced apart from the moveable electrode when the moveable electrode is in an inactivated position and in contact with the moveable electrode when the moveable electrode is in an activated position, and a substrate attached to the dielectric layer on a second side opposite to the first side, the moveable electrode is configured to brake prior to coming in contact with the dielectric layer when the moveable electrode is switchedmore » between the inactivated state and the activated state.« less

RF-MEMS Technology for High-Performance Passives; The challenge of 5G mobile applications

NASA Astrophysics Data System (ADS)

Iannacci, Jacopo

2017-11-01

Commencing with a review of the characteristics of RF-MEMS in relation to 5G, the book proceeds to develop practical insight concerning the design and development of RF-MEMS including case studies of design concepts. Including multiphysics simulation and animated figures, the book will be essential reading for both academic and industrial researchers and engineers.

MEMS Applications in Aerodynamic Measurement Technology

NASA Technical Reports Server (NTRS)

Reshotko, E.; Mehregany, M.; Bang, C.

1998-01-01

Microelectromechanical systems (MEMS) embodies the integration of sensors, actuators, and electronics on a single substrate using integrated circuit fabrication techniques and compatible bulk and surface micromachining processes. Silicon and its derivatives form the material base for the MEMS technology. MEMS devices, including microsensors and microactuators, are attractive because they can be made small (characteristic dimension about 100 microns), be produced in large numbers with uniform performance, include electronics for high performance and sophisticated functionality, and be inexpensive. For aerodynamic measurements, it is preferred that sensors be small so as to approximate measurement at a point, and in fact, MEMS pressure sensors, wall shear-stress sensors, heat flux sensors and micromachined hot wires are nearing application. For the envisioned application to wind tunnel models, MEMS sensors can be placed on the surface or in very shallow grooves. MEMS devices have often been fabricated on stiff, flat silicon substrates, about 0.5 mm thick, and therefore were not easily mounted on curved surfaces. However, flexible substrates are now available and heat-flux sensor arrays have been wrapped around a curved turbine blade. Electrical leads can also be built into the flexible substrate. Thus MEMS instrumented wind tunnel models do not require deep spanwise grooves for tubes and leads that compromise the strength of conventionally instrumented models. With MEMS, even the electrical leads can potentially be eliminated if telemetry of the signals to an appropriate receiver can be implemented. While semiconductor silicon is well known for its electronic properties, it is also an excellent mechanical material for MEMS applications. However, silicon electronics are limited to operations below about 200 C, and silicon's mechanical properties start to diminish above 400 C. In recent years, silicon carbide (SiC) has emerged as the leading material candidate for applications in high temperature environments and can be used for high-temperature MEMS applications. With SiC, diodes and more complex electronics have been shown to operate to about 600 C, while the mechanical properties of SiC are maintained to much higher temperatures. Even when MEMS devices show benefits in the laboratory, there are many packaging challenges for any aeronautics application. Incorporating MEMS into these applications requires new approaches to packaging that goes beyond traditional integrated circuit (IC) packaging technologies. MEMS must interact mechanically, as well as electrically with their environment, making most traditional chip packaging and mounting techniques inadequate. Wind tunnels operate over wide temperature ranges in an environment that is far from being a 'clean-room.' In flight, aircraft are exposed to natural elements (e.g. rain, sun, ice, insects and dirt) and operational interferences(e.g. cleaning and deicing fluids, and maintenance crews). In propulsion systems applications, MEMS devices will have to operate in environments containing gases with very high temperatures, abrasive particles and combustion products. Hence deployment and packaging that maintains the integrity of the MEMS system is crucial. This paper presents an overview of MEMS fabrication and materials, descriptions of available sensors with more details on those being developed in our laboratories, and a discussion of sensor deployment options for wind tunnel and flight applications.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allen, James J.

A microelectromechanical (MEM) optical switching apparatus is disclosed that is based on an erectable mirror which is formed on a rotatable stage using surface micromachining. An electrostatic actuator is also formed on the substrate to rotate the stage and mirror with a high angular precision. The mirror can be erected manually after fabrication of the device and used to redirect an incident light beam at an arbitrary angel and to maintain this state in the absence of any applied electrical power. A 1.times.N optical switch can be formed using a single rotatable mirror. In some embodiments of the present invention,more » a plurality of rotatable mirrors can be configured so that the stages and mirrors rotate in unison when driven by a single micromotor thereby forming a 2.times.2 optical switch which can be used to switch a pair of incident light beams, or as a building block to form a higher-order optical switch.« less

Development of Implantable Wireless Sensor Nodes for Animal Husbandry and MedTech Innovation.

PubMed

Lu, Jian; Zhang, Lan; Zhang, Dapeng; Matsumoto, Sohei; Hiroshima, Hiroshi; Maeda, Ryutaro; Sato, Mizuho; Toyoda, Atsushi; Gotoh, Takafumi; Ohkohchi, Nobuhiro

2018-03-26

In this paper, we report the development, evaluation, and application of ultra-small low-power wireless sensor nodes for advancing animal husbandry, as well as for innovation of medical technologies. A radio frequency identification (RFID) chip with hybrid interface and neglectable power consumption was introduced to enable switching of ON/OFF and measurement mode after implantation. A wireless power transmission system with a maximum efficiency of 70% and an access distance of up to 5 cm was developed to allow the sensor node to survive for a duration of several weeks from a few minutes' remote charge. The results of field tests using laboratory mice and a cow indicated the high accuracy of the collected biological data and bio-compatibility of the package. As a result of extensive application of the above technologies, a fully solid wireless pH sensor and a surgical navigation system using artificial magnetic field and a 3D MEMS magnetic sensor are introduced in this paper, and the preliminary experimental results are presented and discussed.

Performance improvements of MOEMS-based diffractive arrays: address isolation and optical switching

NASA Astrophysics Data System (ADS)

Panaman, Ganesh; Madison, Seth; Sano, Michael; Castracane, James

2005-01-01

Micro-Opto-Electro-Mechanical Systems (MOEMS) have found a variety of applications in fields such as telecommunications, spectroscopy and display technology. MOEMS-based optical switching is currently under investigation for the increased flexibility that such devices provide for reconfiguration of the I/O network for inter-chip communication applications. This potential not only adds an additional degree of freedom for adjustment of transmitter/receiver links but also allows for fine alignment of individual channels in the network link. Further, this use of diffractive arrays for specific applications combines beam steering/adjustment capabilities with the inherent wavelength dependence of the diffractive approach for channel separation and de-multiplexing. Research and development has been concentrated on the progression from single MOEMS components to parallel arrays integrated with optical source arrays for a successful feasibility demonstration. Successful development of such an approach will have a major impact of the next generation communication protocols. This paper will focus on the current status of the MOEMS research program for Free Space Optical inter-chip communication at the College of NanoScale Science and Engineering, University at Albany-SUNY (CNSE). New versions of diffractive arrays stemming from the basic MEMS Compound Grating (MCG; patent #5,999,319) have been produced through various fabrication methods including the MUMPs process1. Most MEMS components relying on electrostatic actuation tend to require high actuation voltages (>20V) compared to the typical 5V levels prevalent in conventional integrated circuits. The specific goal is to yield improved performance while minimizing the power consumption of the components. Structural modifications through the variation in the ruling/electrode spacing distance and array wiring layout through individually addressable gratings have been studied to understand effects on the actuation voltage and cross talk, respectively. A detailed overview of the optical and mechanical properties will be included. Modeling results along with the mechanical and optical testing results have been detailed and compared with previously obtained results. Future work focuses on alternate material sets for a reduction in operational voltage, improvements in optical efficiency and technology demonstrators for verification of massively parallel I/O performance.

Fusion of current technologies with real-time 3D MEMS ladar for novel security and defense applications

NASA Astrophysics Data System (ADS)

Siepmann, James P.

2006-05-01

Through the utilization of scanning MEMS mirrors in ladar devices, a whole new range of potential military, Homeland Security, law enforcement, and civilian applications is now possible. Currently, ladar devices are typically large (>15,000 cc), heavy (>15 kg), and expensive (>$100,000) while current MEMS ladar designs are more than a magnitude less, opening up a myriad of potential new applications. One such application with current technology is a GPS integrated MEMS ladar unit, which could be used for real-time border monitoring or the creation of virtual 3D battlefields after being dropped or propelled into hostile territory. Another current technology that can be integrated into a MEMS ladar unit is digital video that can give high resolution and true color to a picture that is then enhanced with range information in a real-time display format that is easier for the user to understand and assimilate than typical gray-scale or false color images. The problem with using 2-axis MEMS mirrors in ladar devices is that in order to have a resonance frequency capable of practical real-time scanning, they must either be quite small and/or have a low maximum tilt angle. Typically, this value has been less than (< or = to 10 mg-mm2-kHz2)-degrees. We have been able to solve this problem by using angle amplification techniques that utilize a series of MEMS mirrors and/or a specialized set of optics to achieve a broad field of view. These techniques and some of their novel applications mentioned will be explained and discussed herein.

Analysis of the bending stiffness and adhesion effect in RF-MEMS structures

NASA Astrophysics Data System (ADS)

Birleanu, C.; Pustan, M.; Dudescu, C.; Merie, V.; Pintea, I.

2017-02-01

Microelectromechanical system (MEMS) is a special branch with a wide range of applications in sensing, switching and actuating devices. Designing the reliable MEMS for thin free-standing structures like as bridges and cantilevers requires understanding of the tribomechanical properties of the materials and structures. The effect of geometrical dimensions (cross-section dimensions and length) on mechanical and tribological behavior of free-standing MEMS structures made of electroplated gold was analyzed in this paper. Special attention was given to the dependences between stiffness and cantilever length and the dependences between bending stress and variable travel range of actuated load. The force position was moved from the beams free-end toward to the anchor. The tests were performed at room temperature (22°C) and relative humidity RH of 40% with a noise- and vibration-isolated and environment-controlled XE-70 AFM from Park Systems using the contact mode. Each measurement was repeated many times in order to improve the accuracy of the experimental results. The stiffness of a microcantilever varies if the position of the acting force is changed. The experimental results obtained were in good correlation with those obtained analytically.

A review: aluminum nitride MEMS contour-mode resonator

NASA Astrophysics Data System (ADS)

Yunhong, Hou; Meng, Zhang; Guowei, Han; Chaowei, Si; Yongmei, Zhao; Jin, Ning

2016-10-01

Over the past several decades, the technology of micro-electromechanical system (MEMS) has advanced. A clear need of miniaturization and integration of electronics components has had new solutions for the next generation of wireless communications. The aluminum nitride (AlN) MEMS contour-mode resonator (CMR) has emerged and become promising and competitive due to the advantages of the small size, high quality factor and frequency, low resistance, compatibility with integrated circuit (IC) technology, and the ability of integrating multi-frequency devices on a single chip. In this article, a comprehensive review of AlN MEMS CMR technology will be presented, including its basic working principle, main structures, fabrication processes, and methods of performance optimization. Among these, the deposition and etching process of the AlN film will be specially emphasized and recent advances in various performance optimization methods of the CMR will be given through specific examples which are mainly focused on temperature compensation and reducing anchor losses. This review will conclude with an assessment of the challenges and future trends of the CMR. Project supported by National Natural Science Foundation (Nos. 61274001, 61234007, 61504130), the Nurturing and Development Special Projects of Beijing Science and Technology Innovation Base's Financial Support (No. Z131103002813070), and the National Defense Science and Technology Innovation Fund of CAS (No. CXJJ-14-M32).

Wafer-level vacuum/hermetic packaging technologies for MEMS

NASA Astrophysics Data System (ADS)

Lee, Sang-Hyun; Mitchell, Jay; Welch, Warren; Lee, Sangwoo; Najafi, Khalil

2010-02-01

An overview of wafer-level packaging technologies developed at the University of Michigan is presented. Two sets of packaging technologies are discussed: (i) a low temperature wafer-level packaging processes for vacuum/hermeticity sealing, and (ii) an environmentally resistant packaging (ERP) technology for thermal and mechanical control as well as vacuum packaging. The low temperature wafer-level encapsulation processes are implemented using solder bond rings which are first patterned on a cap wafer and then mated with a device wafer in order to encircle and encapsulate the device at temperatures ranging from 200 to 390 °C. Vacuum levels below 10 mTorr were achieved with yields in an optimized process of better than 90%. Pressures were monitored for more than 4 years yielding important information on reliability and process control. The ERP adopts an environment isolation platform in the packaging substrate. The isolation platform is designed to provide low power oven-control, vibration isolation and shock protection. It involves batch flip-chip assembly of a MEMS device onto the isolation platform wafer. The MEMS device and isolation structure are encapsulated at the wafer-level by another substrate with vertical feedthroughs for vacuum/hermetic sealing and electrical signal connections. This technology was developed for high performance gyroscopes, but can be applied to any type of MEMS device.

Macro, mini, micro and nano (M(sup 3)N) technologies for the future

NASA Technical Reports Server (NTRS)

Friedrich, Craig R.; Warrington, Robert O.; Gao, Robert X.; Lin, Gang

1993-01-01

Microelectromechanical systems (MEMS), micro systems technologies (MST), and micromanufacturing are relatively recent phrases or acronyms that have become synonymous with the design, development, and manufacture of 'micro' devices and systems. Micromanufacturing encompasses MEMS or MST and, in addition, includes all of the processes involved in the production of micro things. Integration of mechanical and electrical components, including built-in computers, can be formed into systems which must be connected to the macroworld. Macro, mini, micro, and nano technologies are all a part of MEMS or micromanufacturing. At this point in the development of the technology, it is becoming apparent that mini systems, with micro components, could very well be the economic drivers of the technology for the foreseeable future. Initial research in the fabrication of microdevices using IC processing technology took place over thirty years ago. Anisotropic etching of silicon was used to produce piezoresistive diaphragms. Since the early 60's, there has been gradual progress in MEMS until the early 1980's when worldwide interest in the technology really started to develop. During this time high aspect ratio micromachining using x rays was started in Germany. In 1987 the concept of a 'silicon micromechanics foundry' was proposed. Since then the interest in the U.S., Germany, and Japan has increased to the point where hundreds of millions of dollars of research monies are being funneled into the technology (at least in Germany and Japan) and the technology has been classified as critical or as a technology or national importance by the U.S. government.

BioMEMS and Lab-on-a-Chip Course Education at West Virginia University

PubMed Central

Liu, Yuxin

2011-01-01

With the rapid growth of Biological/Biomedical MicroElectroMechanical Systems (BioMEMS) and microfluidic-based lab-on-a-chip (LOC) technology to biological and biomedical research and applications, demands for educated and trained researchers and technicians in these fields are rapidly expanding. Universities are expected to develop educational plans to address these specialized needs in BioMEMS, microfluidic and LOC science and technology. A course entitled BioMEMS and Lab-on-a-Chip was taught recently at the senior undergraduate and graduate levels in the Department of Computer Science and Electrical Engineering at West Virginia University (WVU). The course focused on the basic principles and applications of BioMEMS and LOC technology to the areas of biomedicine, biology, and biotechnology. The course was well received and the enrolled students had diverse backgrounds in electrical engineering, material science, biology, mechanical engineering, and chemistry. Student feedback and a review of the course evaluations indicated that the course was effective in achieving its objectives. Student presentations at the end of the course were a highlight and a valuable experience for all involved. The course proved successful and will continue to be offered regularly. This paper provides an overview of the course as well as some development and future improvements. PMID:25586697

MEMS scanning micromirror for optical coherence tomography.

PubMed

Strathman, Matthew; Liu, Yunbo; Keeler, Ethan G; Song, Mingli; Baran, Utku; Xi, Jiefeng; Sun, Ming-Ting; Wang, Ruikang; Li, Xingde; Lin, Lih Y

2015-01-01

This paper describes an endoscopic-inspired imaging system employing a micro-electromechanical system (MEMS) micromirror scanner to achieve beam scanning for optical coherence tomography (OCT) imaging. Miniaturization of a scanning mirror using MEMS technology can allow a fully functional imaging probe to be contained in a package sufficiently small for utilization in a working channel of a standard gastroesophageal endoscope. This work employs advanced image processing techniques to enhance the images acquired using the MEMS scanner to correct non-idealities in mirror performance. The experimental results demonstrate the effectiveness of the proposed technique.

MEMS scanning micromirror for optical coherence tomography

PubMed Central

Strathman, Matthew; Liu, Yunbo; Keeler, Ethan G.; Song, Mingli; Baran, Utku; Xi, Jiefeng; Sun, Ming-Ting; Wang, Ruikang; Li, Xingde; Lin, Lih Y.

2014-01-01

This paper describes an endoscopic-inspired imaging system employing a micro-electromechanical system (MEMS) micromirror scanner to achieve beam scanning for optical coherence tomography (OCT) imaging. Miniaturization of a scanning mirror using MEMS technology can allow a fully functional imaging probe to be contained in a package sufficiently small for utilization in a working channel of a standard gastroesophageal endoscope. This work employs advanced image processing techniques to enhance the images acquired using the MEMS scanner to correct non-idealities in mirror performance. The experimental results demonstrate the effectiveness of the proposed technique. PMID:25657887

3D MEMS in Standard Processes: Fabrication, Quality Assurance, and Novel Measurement Microstructures

NASA Technical Reports Server (NTRS)

Lin, Gisela; Lawton, Russell A.

2000-01-01

Three-dimensional MEMS microsystems that are commercially fabricated require minimal post-processing and are easily integrated with CMOS signal processing electronics. Measurements to evaluate the fabrication process (such as cross-sectional imaging and device performance characterization) provide much needed feedback in terms of reliability and quality assurance. MEMS technology is bringing a new class of microscale measurements to fruition. The relatively small size of MEMS microsystems offers the potential for higher fidelity recordings compared to macrosize counterparts, as illustrated in the measurement of muscle cell forces.

Three-dimensional microelectromechanical tilting platform operated by gear-driven racks

DOEpatents

Klody, Kelly A.; Habbit, Jr., Robert D.

2005-11-01

A microelectromechanical (MEM) tiltable-platform apparatus is disclosed which utilizes a light-reflective platform (i.e. a micromirror) which is supported above a substrate by flexures which can be bent upwards to tilt the platform in any direction over an angle of generally .+-.10 degrees using a gear-driven rack attached to each flexure. Each rack is driven by a rotary microengine (i.e. a micromotor); and an optional thermal actuator can be used in combination with each microengine for initially an initial uplifting of the platform away from the substrate. The MEM apparatus has applications for optical switching (e.g. between a pair of optical fibers) or for optical beam scanning.

Sputtered highly oriented PZT thin films for MEMS applications

NASA Astrophysics Data System (ADS)

Kalpat, Sriram S.

Recently there has been an explosion of interest in the field of micro-electro-mechanical systems (MEMS). MEMS device technology has become critical in the growth of various fields like medical, automotive, chemical, and space technology. Among the many applications of ferroelectric thin films in MEMS devices, microfluidics is a field that has drawn considerable amount of research from bio-technology industries as well as chemical and semiconductor manufacturing industries. PZT thin films have been identified as best suited materials for micro-actuators and micro-sensors used in MEMS devices. A promising application for piezoelectric thin film based MEMS devices is disposable drug delivery systems that are capable of sensing biological parameters, mixing and delivering minute and precise amounts of drugs using micro-pumps or micro mixers. These devices call for low driving voltages, so that they can be battery operated. Improving the performance of the actuator material is critical in achieving battery operated disposal drug delivery systems. The device geometry and power consumption in MEMS devices largely depends upon the piezoelectric constant of the films, since they are most commonly used to convert electrical energy into a mechanical response of a membrane or cantilever and vice versa. Phenomenological calculation on the crystal orientation dependence of piezoelectric coefficients for PZT single crystal have reported a significant enhancement of the piezoelectric d33 constant by more than 3 times along [001] in the rhombohedral phase as compared to the conventionally used orientation PZT(111) since [111] is the along the spontaneous polarization direction. This could mean considerable improvement in the MEMS device performance and help drive the operating voltages lower. The motivation of this study is to investigate the crystal orientation dependence of both dielectric and piezoelectric coefficients of PZT thin films in order to select the appropriate orientation that could improve the MEMS device performance. Potential application of these devices is as battery operated disposable drug delivery systems. This work will also investigate the fabrication of a flexural plate wave based microfluidic device using the PZT thin film of appropriate orientation that would enhance the device performance. (Abstract shortened by UMI.)

Flexible MEMS: A novel technology to fabricate flexible sensors and electronics

NASA Astrophysics Data System (ADS)

Tu, Hongen

This dissertation presents the design and fabrication techniques used to fabricate flexible MEMS (Micro Electro Mechanical Systems) devices. MEMS devices and CMOS(Complementary Metal-Oxide-Semiconductor) circuits are traditionally fabricated on rigid substrates with inorganic semiconductor materials such as Silicon. However, it is highly desirable that functional elements like sensors, actuators or micro fluidic components to be fabricated on flexible substrates for a wide variety of applications. Due to the fact that flexible substrate is temperature sensitive, typically only low temperature materials, such as polymers, metals, and organic semiconductor materials, can be directly fabricated on flexible substrates. A novel technology based on XeF2(xenon difluoride) isotropic silicon etching and parylene conformal coating, which is able to monolithically incorporate high temperature materials and fluidic channels, was developed at Wayne State University. The technology was first implemented in the development of out-of-plane parylene microneedle arrays that can be individually addressed by integrated flexible micro-channels. These devices enable the delivery of chemicals with controlled temporal and spatial patterns and allow us to study neurotransmitter-based retinal prosthesis. The technology was further explored by adopting the conventional SOI-CMOS processes. High performance and high density CMOS circuits can be first fabricated on SOI wafers, and then be integrated into flexible substrates. Flexible p-channel MOSFETs (Metal-Oxide-Semiconductor Field-Effect-Transistors) were successfully integrated and tested. Integration of pressure sensors and flow sensors based on single crystal silicon has also been demonstrated. A novel smart yarn technology that enables the invisible integration of sensors and electronics into fabrics has been developed. The most significant advantage of this technology is its post-MEMS and post-CMOS compatibility. Various high-performance MEMS devices and electronics can be integrated into flexible substrates. The potential of our technology is enormous. Many wearable and implantable devices can be developed based on this technology.

Realization of MEMS-IC Vertical Integration Utilizing Smart Bumpless Bonding

NASA Astrophysics Data System (ADS)

Shiozaki, Masayoshi; Moriguchi, Makoto; Sasaki, Sho; Oba, Masatoshi

This paper reports fundamental technologies, properties, and new experimental results of SBB (Smart Bumpless Bonding) to realize MEMS-IC vertical integration. Although conventional bonding technologies have had difficulties integrating MEMS and its processing circuit because of their rough bonding surfaces, fragile structures, and thermal restriction, SBB technology realized the vertical integration without thermal treatment, any adhesive materials including bumps, and chemical mechanical polishing. The SBB technology bonds sealing parts for vacuum sealing and electrodes for electrical connection simultaneously as published in previous experimental study. The plasma CVD SiO2 is utilized to realize vacuum sealing as sealing material. And Au projection studs are formed on each electrode and connected electrically between two wafers by compressive plastic deformation and surface activation. In this paper, new experimental results including vacuum sealing properties, electrical improvement, IC bonding results on the described fundamental concept and properties are reported.

Liquid Tunable Microlenses based on MEMS techniques

PubMed Central

Zeng, Xuefeng; Jiang, Hongrui

2013-01-01

The recent rapid development in microlens technology has provided many opportunities for miniaturized optical systems, and has found a wide range of applications. Of these microlenses, tunable-focus microlenses are of special interest as their focal lengths can be tuned using micro-scale actuators integrated with the lens structure. Realization of such tunable microlens generally relies on the microelectromechanical system (MEMS) technologies. Here, we review the recent progress in tunable liquid microlenses. The underlying physics relevant to these microlenses are first discussed, followed by description of three main categories of tunable microlenses involving MEMS techniques, mechanically driven, electrically driven, and those integrated within microfluidic systems. PMID:24163480

Design of a novel passive flexure-based mechanism for microelectromechanical system optical switch assembly

NASA Astrophysics Data System (ADS)

Zhang, Jianbin; Sun, Xiantao; Chen, Weihai; Chen, Wenjie; Jiang, Lusha

2014-12-01

In microelectromechanical system (MEMS) optical switch assembly, the collision always exists between the optical fiber and the edges of the U-groove due to the positioning errors between them. It will cause the irreparable damage since the optical fiber and the silicon-made U-groove are usually very fragile. Typical solution is first to detect the positioning errors by the machine vision or high-resolution sensors and then to actively eliminate them with the aid of the motion of precision mechanisms. However, this method will increase the cost and complexity of the system. In this paper, we present a passive compensation method to accommodate the positioning errors. First, we study the insertion process of the optical fiber into the U-groove to analyze all possible positioning errors as well as the conditions of successful insertion. Then, a novel passive flexure-based mechanism based on the remote center of compliance concept is designed to satisfy the required insertion condition. The pseudo-rigid-body-model method is utilized to calculate the stiffness of the mechanism along the different directions, which is verified by finite element analysis (FEA). Finally, a prototype of the passive flexure-based mechanism is fabricated for performance tests. Both FEA and experimental results indicate that the designed mechanism can be used to the MEMS optical switch assembly.

Multiscale contact mechanics model for RF-MEMS switches with quantified uncertainties

NASA Astrophysics Data System (ADS)

Kim, Hojin; Huda Shaik, Nurul; Xu, Xin; Raman, Arvind; Strachan, Alejandro

2013-12-01

We introduce a multiscale model for contact mechanics between rough surfaces and apply it to characterize the force-displacement relationship for a metal-dielectric contact relevant for radio frequency micro-electromechanicl system (MEMS) switches. We propose a mesoscale model to describe the history-dependent force-displacement relationships in terms of the surface roughness, the long-range attractive interaction between the two surfaces, and the repulsive interaction between contacting asperities (including elastic and plastic deformation). The inputs to this model are the experimentally determined surface topography and the Hamaker constant as well as the mechanical response of individual asperities obtained from density functional theory calculations and large-scale molecular dynamics simulations. The model captures non-trivial processes including the hysteresis during loading and unloading due to plastic deformation, yet it is computationally efficient enough to enable extensive uncertainty quantification and sensitivity analysis. We quantify how uncertainties and variability in the input parameters, both experimental and theoretical, affect the force-displacement curves during approach and retraction. In addition, a sensitivity analysis quantifies the relative importance of the various input quantities for the prediction of force-displacement during contact closing and opening. The resulting force-displacement curves with quantified uncertainties can be directly used in device-level simulations of micro-switches and enable the incorporation of atomic and mesoscale phenomena in predictive device-scale simulations.

Design of a novel passive flexure-based mechanism for microelectromechanical system optical switch assembly.

PubMed

Zhang, Jianbin; Sun, Xiantao; Chen, Weihai; Chen, Wenjie; Jiang, Lusha

2014-12-01

In microelectromechanical system (MEMS) optical switch assembly, the collision always exists between the optical fiber and the edges of the U-groove due to the positioning errors between them. It will cause the irreparable damage since the optical fiber and the silicon-made U-groove are usually very fragile. Typical solution is first to detect the positioning errors by the machine vision or high-resolution sensors and then to actively eliminate them with the aid of the motion of precision mechanisms. However, this method will increase the cost and complexity of the system. In this paper, we present a passive compensation method to accommodate the positioning errors. First, we study the insertion process of the optical fiber into the U-groove to analyze all possible positioning errors as well as the conditions of successful insertion. Then, a novel passive flexure-based mechanism based on the remote center of compliance concept is designed to satisfy the required insertion condition. The pseudo-rigid-body-model method is utilized to calculate the stiffness of the mechanism along the different directions, which is verified by finite element analysis (FEA). Finally, a prototype of the passive flexure-based mechanism is fabricated for performance tests. Both FEA and experimental results indicate that the designed mechanism can be used to the MEMS optical switch assembly.

MEMS Deformable Mirror Technology Development for Space-Based Exoplanet Detection

NASA Astrophysics Data System (ADS)

Bierden, Paul; Cornelissen, S.; Ryan, P.

2014-01-01

In the search for earth-like extrasolar planets that has become an important objective for NASA, a critical technology development requirement is to advance deformable mirror (DM) technology. High-actuator-count DMs are critical components for nearly all proposed coronagraph instrument concepts. The science case for exoplanet imaging is strong, and rapid recent advances in test beds with DMs made using microelectromechanical system (MEMS) technology have motivated a number of compelling mission concepts that set technical specifications for their use as wavefront controllers. This research will advance the technology readiness of the MEMS DMs components that are currently at the forefront of the field, and the project will be led by the manufacturer of those components, Boston Micromachines Corporation (BMC). The project aims to demonstrate basic functionality and performance of this key component in critical test environments and in simulated operational environments, while establishing model-based predictions of its performance relative to launch and space environments. Presented will be the current status of the project with modeling and initial test results.

MEMS for Space Flight Applications

NASA Technical Reports Server (NTRS)

Lawton, R.

1998-01-01

Micro-Electrical Mechanical Systems (MEMS) are entering the stage of design and verification to demonstrate the utility of the technology for a wide range of applications including sensors and actuators for military, space, medical, industrial, consumer, automotive and instrumentation products.

SMA Foils for MEMS: From Material Properties to the Engineering of Microdevices

NASA Astrophysics Data System (ADS)

Kohl, Manfred; Ossmer, Hinnerk; Gueltig, Marcel; Megnin, Christof

2018-03-01

In the early nineties, microelectromechanical systems (MEMS) technology has been still in its infancy. As silicon (Si) is not a transducer material, it was clear at the very beginning that mechanically active materials had to be introduced to MEMS in order to enable functional microdevices with actuation capability beyond electrostatics. At that time, shape memory alloys (SMAs) have been available in bulk form, mainly as SMA wires and SMA plates. On the macro scale, these materials show highest work densities compared to other actuation principles in the order of 107 J/m3, which stimulated research on the integration of SMA to MEMS. Subsequently, two approaches for producing planar materials have been initiated (1) magnetron sputtering of SMA thin films and (2) the integration of rolled SMA foils, which both turned out to be very successful creating a paradigm change in microactuation technology. The following review covers important milestones of the research and development of SMA foil-based microactuators including materials characterization, design engineering, technology, and demonstrator development as well as first commercial products.

SMA Foils for MEMS: From Material Properties to the Engineering of Microdevices

NASA Astrophysics Data System (ADS)

Kohl, Manfred; Ossmer, Hinnerk; Gueltig, Marcel; Megnin, Christof

2017-12-01

In the early nineties, microelectromechanical systems (MEMS) technology has been still in its infancy. As silicon (Si) is not a transducer material, it was clear at the very beginning that mechanically active materials had to be introduced to MEMS in order to enable functional microdevices with actuation capability beyond electrostatics. At that time, shape memory alloys (SMAs) have been available in bulk form, mainly as SMA wires and SMA plates. On the macro scale, these materials show highest work densities compared to other actuation principles in the order of 107 J/m3, which stimulated research on the integration of SMA to MEMS. Subsequently, two approaches for producing planar materials have been initiated (1) magnetron sputtering of SMA thin films and (2) the integration of rolled SMA foils, which both turned out to be very successful creating a paradigm change in microactuation technology. The following review covers important milestones of the research and development of SMA foil-based microactuators including materials characterization, design engineering, technology, and demonstrator development as well as first commercial products.

Resonant Magnetic Field Sensors Based On MEMS Technology.

PubMed

Herrera-May, Agustín L; Aguilera-Cortés, Luz A; García-Ramírez, Pedro J; Manjarrez, Elías

2009-01-01

Microelectromechanical systems (MEMS) technology allows the integration of magnetic field sensors with electronic components, which presents important advantages such as small size, light weight, minimum power consumption, low cost, better sensitivity and high resolution. We present a discussion and review of resonant magnetic field sensors based on MEMS technology. In practice, these sensors exploit the Lorentz force in order to detect external magnetic fields through the displacement of resonant structures, which are measured with optical, capacitive, and piezoresistive sensing techniques. From these, the optical sensing presents immunity to electromagnetic interference (EMI) and reduces the read-out electronic complexity. Moreover, piezoresistive sensing requires an easy fabrication process as well as a standard packaging. A description of the operation mechanisms, advantages and drawbacks of each sensor is considered. MEMS magnetic field sensors are a potential alternative for numerous applications, including the automotive industry, military, medical, telecommunications, oceanographic, spatial, and environment science. In addition, future markets will need the development of several sensors on a single chip for measuring different parameters such as the magnetic field, pressure, temperature and acceleration.

Resonant Magnetic Field Sensors Based On MEMS Technology

PubMed Central

Herrera-May, Agustín L.; Aguilera-Cortés, Luz A.; García-Ramírez, Pedro J.; Manjarrez, Elías

2009-01-01

Microelectromechanical systems (MEMS) technology allows the integration of magnetic field sensors with electronic components, which presents important advantages such as small size, light weight, minimum power consumption, low cost, better sensitivity and high resolution. We present a discussion and review of resonant magnetic field sensors based on MEMS technology. In practice, these sensors exploit the Lorentz force in order to detect external magnetic fields through the displacement of resonant structures, which are measured with optical, capacitive, and piezoresistive sensing techniques. From these, the optical sensing presents immunity to electromagnetic interference (EMI) and reduces the read-out electronic complexity. Moreover, piezoresistive sensing requires an easy fabrication process as well as a standard packaging. A description of the operation mechanisms, advantages and drawbacks of each sensor is considered. MEMS magnetic field sensors are a potential alternative for numerous applications, including the automotive industry, military, medical, telecommunications, oceanographic, spatial, and environment science. In addition, future markets will need the development of several sensors on a single chip for measuring different parameters such as the magnetic field, pressure, temperature and acceleration. PMID:22408480

Thermoelectric microdevice fabricated by a MEMS-like electrochemical process

NASA Technical Reports Server (NTRS)

Snyder, G. Jeffrey; Lim, James R.; Huang, Chen-Kuo; Fleurial, Jean-Pierre

2003-01-01

Microelectromechanical systems (MEMS) are the basis of many rapidly growing technologies, because they combine miniature sensors and actuators with communications and electronics at low cost. Commercial MEMS fabrication processes are limited to silicon-based materials or two-dimensional structures. Here we show an inexpensive, electrochemical technique to build MEMS-like structures that contain several different metals and semiconductors with three-dimensional bridging structures. We demonstrate this technique by building a working microthermoelectric device. Using repeated exposure and development of multiple photoresist layers, several different metals and thermoelectric materials are fabricated in a three-dimensional structure. A device containing 126 n-type and p-type (Bi, Sb)2Te3 thermoelectric elements, 20 microm tall and 60 microm in diameter with bridging metal interconnects, was fabricated and cooling demonstrated. Such a device should be of technological importance for precise thermal control when operating as a cooler, and for portable power when operating as a micro power generator.

A MEMS-based super fast dew point hygrometer—construction and medical applications

NASA Astrophysics Data System (ADS)

Jachowicz, Ryszard S.; Weremczuk, Jerzy; Paczesny, Daniel; Tarapata, Grzegorz

2009-12-01

The paper shows how MEMS (micro-electro-mechanical system) technology and a modified principle of fast temperature control (by heat injection instead of careful control of cooling) can considerably improve the dynamic parameters of dew point hygrometers. Some aspects of MEMS-type integrated sensor construction and technology, whole measurement system design, the control algorithm to run the system as well as empirical dynamic parameters from the tests are discussed too. The hygrometer can easily obtain five to six measurements per second with an uncertainty of less than 0.3 K. The meter range is between -10 °C and 40 °C dew point. In the second part of the paper (section 2), two different successful applications in medicine based on fast humidity measurements have been discussed. Some specific constructions of these super fast dew point hygrometers based on a MEMS sensor as well as limited empirical results from clinical tests have been reported too.

Sensors and Micromachined Devices for the Automotive and New Markets: The Delphi Delco Electronics MEMS Story.

NASA Astrophysics Data System (ADS)

Logsdon, James

2002-03-01

This presentation will provide a brief history of the development of MEMS products and technology, beginning with the manifold absolute pressure sensor in the late seventies through the current variety of Delphi Delco Electronics sensors available today. The technology development of micromachining from uncompensated P plus etch stops to deep reactive ion etching and the technology development of wafer level packaging from electrostatic bonding to glass frit sealing and silicon to silicon direct bonding will be reviewed.

MemFlash device: floating gate transistors as memristive devices for neuromorphic computing

NASA Astrophysics Data System (ADS)

Riggert, C.; Ziegler, M.; Schroeder, D.; Krautschneider, W. H.; Kohlstedt, H.

2014-10-01

Memristive devices are promising candidates for future non-volatile memory applications and mixed-signal circuits. In the field of neuromorphic engineering these devices are especially interesting to emulate neuronal functionality. Therefore, new materials and material combinations are currently investigated, which are often not compatible with Si-technology processes. The underlying mechanisms of the device often remain unclear and are paired with low device endurance and yield. These facts define the current most challenging development tasks towards a reliable memristive device technology. In this respect, the MemFlash concept is of particular interest. A MemFlash device results from a diode configuration wiring scheme of a floating gate transistor, which enables the persistent device resistance to be varied according to the history of the charge flow through the device. In this study, we investigate the scaling conditions of the floating gate oxide thickness with respect to possible applications in the field of neuromorphic engineering. We show that MemFlash cells exhibit essential features with respect to neuromorphic applications. In particular, cells with thin floating gate oxides show a limited synaptic weight growth together with low energy dissipation. MemFlash cells present an attractive alternative for state-of-art memresitive devices. The emulation of associative learning is discussed by implementing a single MemFlash cell in an analogue circuit.

Characterizing the reliability of a bioMEMS-based cantilever sensor

NASA Astrophysics Data System (ADS)

Bhalerao, Kaustubh D.

2004-12-01

The cantilever-based BioMEMS sensor represents one instance from many competing ideas of biosensor technology based on Micro Electro Mechanical Systems. The advancement of BioMEMS from laboratory-scale experiments to applications in the field will require standardization of their components and manufacturing procedures as well as frameworks to evaluate their performance. Reliability, the likelihood with which a system performs its intended task, is a compact mathematical description of its performance. The mathematical and statistical foundation of systems-reliability has been applied to the cantilever-based BioMEMS sensor. The sensor is designed to detect one aspect of human ovarian cancer, namely the over-expression of the folate receptor surface protein (FR-alpha). Even as the application chosen is clinically motivated, the objective of this study was to demonstrate the underlying systems-based methodology used to design, develop and evaluate the sensor. The framework development can be readily extended to other BioMEMS-based devices for disease detection and will have an impact in the rapidly growing $30 bn industry. The Unified Modeling Language (UML) is a systems-based framework for design and development of object-oriented information systems which has potential application for use in systems designed to interact with biological environments. The UML has been used to abstract and describe the application of the biosensor, to identify key components of the biosensor, and the technology needed to link them together in a coherent manner. The use of the framework is also demonstrated in computation of system reliability from first principles as a function of the structure and materials of the biosensor. The outcomes of applying the systems-based framework to the study are the following: (1) Characterizing the cantilever-based MEMS device for disease (cell) detection. (2) Development of a novel chemical interface between the analyte and the sensor that provides a degree of selectivity towards the disease. (3) Demonstrating the performance and measuring the reliability of the biosensor prototype, and (4) Identification of opportunities in technological development in order to further refine the proposed biosensor. Application of the methodology to design develop and evaluate the reliability of BioMEMS devices will be beneficial in the streamlining the growth of the BioMEMS industry, while providing a decision-support tool in comparing and adopting suitable technologies from available competing options.

CNES reliability approach for the qualification of MEMS for space

NASA Astrophysics Data System (ADS)

Pressecq, Francis; Lafontan, Xavier; Perez, Guy; Fortea, Jean-Pierre

2001-10-01

This paper describes the reliability approach performs at CNES to evaluate MEMS for space application. After an introduction and a detailed state of the art on the space requirements and on the use of MEMS for space, different approaches for taking into account MEMS in the qualification phases are presented. CNES proposes improvement to theses approaches in term of failure mechanisms identification. Our approach is based on a design and test phase deeply linked with a technology study. This workflow is illustrated with an example: the case of a variable capacitance processed with MUMPS process is presented.

Modeling of optical mirror and electromechanical behavior

NASA Astrophysics Data System (ADS)

Wang, Fang; Lu, Chao; Liu, Zishun; Liu, Ai Q.; Zhang, Xu M.

2001-10-01

This paper presents finite element (FE) simulation and theoretical analysis of novel MEMS fiber-optical switches actuated by electrostatic attraction. FE simulation for the switches under static and dynamic loading are first carried out to reveal the mechanical characteristics of the minimum or critical switching voltages, the natural frequencies, mode shapes and response under different levels of electrostatic attraction load. To validate the FE simulation results, a theoretical (or analytical) model is then developed for one specific switch, i.e., Plate_40_104. Good agreement is found between the FE simulation and the analytical results. From both FE simulation and theoretical analysis, the critical switching voltage for Plate_40_104 is derived to be 238 V for the switching angel of 12 degree(s). The critical switching on and off times are 431 microsecond(s) and 67 microsecond(s) , respectively. The present study not only develops good FE and analytical models, but also demonstrates step by step a method to simplify a real optical switch structure with reference to the FE simulation results for analytical purpose. With the FE and analytical models, it is easy to obtain any information about the mechanical behaviors of the optical switches, which are helpful in yielding optimized design.

Nanomechanical Optical Fiber with Embedded Electrodes Actuated by Joule Heating.

PubMed

Lian, Zhenggang; Segura, Martha; Podoliak, Nina; Feng, Xian; White, Nicholas; Horak, Peter

2014-07-31

Nanomechanical optical fibers with metal electrodes embedded in the jacket were fabricated by a multi-material co-draw technique. At the center of the fibers, two glass cores suspended by thin membranes and surrounded by air form a directional coupler that is highly temperature-dependent. We demonstrate optical switching between the two fiber cores by Joule heating of the electrodes with as little as 0.4 W electrical power, thereby demonstrating an electrically actuated all-fiber microelectromechanical system (MEMS). Simulations show that the main mechanism for optical switching is the transverse thermal expansion of the fiber structure.

DMD: a digital light processing application to projection displays

NASA Astrophysics Data System (ADS)

Feather, Gary A.

1989-01-01

Summary Revolutionary technologies achieve rapid product and subsequent business diffusion only when the in- ventors focus on technology application, maturation, and proliferation. A revolutionary technology is emerg- ing with micro-electromechanical systems (MEMS). MEMS are being developed by leveraging mature semi- conductor processing coupled with mechanical systems into complete, integrated, useful systems. The digital micromirror device (DMD), a Texas Instruments invented MEMS, has focused on its application to projec- tion displays. The DMD has demonstrated its application as a digital light processor, processing and produc- ing compelling computer and video projection displays. This tutorial discusses requirements in the projection display market and the potential solutions offered by this digital light processing system. The seminar in- cludes an evaluation of the market, system needs, design, fabrication, application, and performance results of a system using digital light processing solutions.

Packaging of MEMS/MOEMS and nanodevices: reliability, testing, and characterization aspects

NASA Astrophysics Data System (ADS)

Tekin, Tolga; Ngo, Ha-Duong; Wittler, Olaf; Bouhlal, Bouchaib; Lang, Klaus-Dieter

2011-02-01

The last decade witnessed an explosive growth in research and development efforts devoted to MEMS devices and packaging. The successfully developed MEMS devices are, for example inkjet, pressure sensors, silicon microphones, accelerometers, gyroscopes, MOEMS, micro fuel cells and emerging MEMS. For the next decade, MEMS/MOEMS and nanodevice based products will penetrate into IT, telecommunications, automotive, defense, life sciences, medical and implantable applications. Forecasts say the MEMS market to be $14 billion by 2012. The packaging cost of MEMS/MOEMS products in general is about 70 percent. Unlike today's electronics IC packaging, their packaging are custom-built and difficult due to the moving structural elements. In order for the moving elements of a MEMS device to move effectively in a well-controlled atmosphere, hermetic sealing of the MEMS device in a cap is necessary. For some MEMS devices, such as resonators and gyroscopes, vacuum packaging is required. Usually, the cap is processed at the wafer level, and thus MEMS packaging is truly a wafer level packaging. In terms of MEMS/MOEMS and nanodevice packaging, there are still many critical issues need to be addressed due to the increasing integration density supported by 3D heterogeneous integration of multi-physic components/layers consisting of photonics, electronics, rf, plasmonics, and wireless. The infrastructure of MEMS/MOEMS and nanodevices and their packaging is not well established yet. Generic packaging platform technologies are not available. Some of critical issues have been studied intensively in the last years. In this paper we will discuss about processes, reliability, testing and characterization of MEMS/MOEMS and nanodevice packaging.

System Modeling of a MEMS Vibratory Gyroscope and Integration to Circuit Simulation.

PubMed

Kwon, Hyukjin J; Seok, Seyeong; Lim, Geunbae

2017-11-18

Recently, consumer applications have dramatically created the demand for low-cost and compact gyroscopes. Therefore, on the basis of microelectromechanical systems (MEMS) technology, many gyroscopes have been developed and successfully commercialized. A MEMS gyroscope consists of a MEMS device and an electrical circuit for self-oscillation and angular-rate detection. Since the MEMS device and circuit are interactively related, the entire system should be analyzed together to design or test the gyroscope. In this study, a MEMS vibratory gyroscope is analyzed based on the system dynamic modeling; thus, it can be mathematically expressed and integrated into a circuit simulator. A behavioral simulation of the entire system was conducted to prove the self-oscillation and angular-rate detection and to determine the circuit parameters to be optimized. From the simulation, the operating characteristic according to the vacuum pressure and scale factor was obtained, which indicated similar trends compared with those of the experimental results. The simulation method presented in this paper can be generalized to a wide range of MEMS devices.

Dynamic metasurface lens based on MEMS technology

NASA Astrophysics Data System (ADS)

Roy, Tapashree; Zhang, Shuyan; Jung, Il Woong; Troccoli, Mariano; Capasso, Federico; Lopez, Daniel

2018-02-01

In the recent years, metasurfaces, being flat and lightweight, have been designed to replace bulky optical components with various functions. We demonstrate a monolithic Micro-Electro-Mechanical System (MEMS) integrated with a metasurface-based flat lens that focuses light in the mid-infrared spectrum. A two-dimensional scanning MEMS platform controls the angle of the lens along two orthogonal axes by ±9°, thus enabling dynamic beam steering. The device could be used to compensate for off-axis incident light and thus correct for aberrations such as coma. We show that for low angular displacements, the integrated lens-on-MEMS system does not affect the mechanical performance of the MEMS actuators and preserves the focused beam profile as well as the measured full width at half maximum. We envision a new class of flat optical devices with active control provided by the combination of metasurfaces and MEMS for a wide range of applications, such as miniaturized MEMS-based microscope systems, LIDAR scanners, and projection systems.

Controlling Variable Emittance (MEMS) Coatings for Space Applications

NASA Technical Reports Server (NTRS)

Farrar, D.; Schneider, W.; Osiander, R.; Champion, J. L.; Darrin, A. G.; Douglas, Donya; Swanson, Ted D.

2003-01-01

Small spacecraft, including micro and nanosats, as they are envisioned for future missions, will require an alternative means to achieve thermal control due to their small power and mass budgets. One of the proposed alternatives is Variable Emittance (Vari-E) Coatings for spacecraft radiators. Space Technology-5 (ST-5) is a technology demonstration mission through NASA Goddard Space Flight Center (GSFC) that will utilize Vari-E Coatings. This mission involves a constellation of three (3) satellites in a highly elliptical orbit with a perigee altitude of approximately 200 kilometers and an apogee of approximately 38,000 kilometers. Such an environment will expose the spacecraft to a wide swing in the thermal and radiation environment of the earth's atmosphere. There are three (3) different technologies associated with this mission. The three technologies are electrophoretic, electrochromic, and Micro ElectroMechanical Systems (MEMS). The ultimate goal is to make use of Van-E coatings, in order to achieve various levels of thermal control. The focus of this paper is to highlight the Vari-E Coating MEMS instrument, with an emphasis on the Electronic Control Unit responsible for operating the MEMS device. The Test & Evaluation approach, along with the results, is specific for application on ST-5, yet the information provides a guideline for future experiments and/or thermal applications on the exterior structure of a spacecraft.

BioMEMS –Advancing the Frontiers of Medicine

PubMed Central

James, Teena; Mannoor, Manu Sebastian; Ivanov, Dentcho V.

2008-01-01

Biological and medical application of micro-electro-mechanical-systems (MEMS) is currently seen as an area of high potential impact. Integration of biology and microtechnology has resulted in the development of a number of platforms for improving biomedical and pharmaceutical technologies. This review provides a general overview of the applications and the opportunities presented by MEMS in medicine by classifying these platforms according to their applications in the medical field. PMID:27873858

Dual Mode Thin Film Bulk Acoustic Resonators (FBARs) Based on AlN, ZnO and GaN Films with Tilted c-Axis Orientation

DTIC Science & Technology

2010-01-01

TERMS MEMS , acoustic wave devices, acoustic wave sensors Qing-Ming Wang University of Pittsburgh 123 University Place University Club Pittsburgh, PA...resonators,” Proc. SPIE Vol. 6223, 62230I, Micro ( MEMS ) and Nanotechnologies for Space Applications; Thomas George, Zhong-Yang Cheng; Eds. (May...microelectromechanical resonators has been recognized as a technological challenge in the current microelectronics and MEMS development. The

Fast tunable blazed MEMS grating for external cavity lasers

NASA Astrophysics Data System (ADS)

Tormen, Maurizio; Niedermann, Philippe; Hoogerwerf, Arno; Shea, Herbert; Stanley, Ross

2017-11-01

Diffractive MEMS are interesting for a wide range of applications, including displays, scanners or switching elements. Their advantages are compactness, potentially high actuation speed and in the ability to deflect light at large angles. We have designed and fabricated deformable diffractive MEMS grating to be used as tuning elements for external cavity lasers. The resulting device is compact, has wide tunability and a high operating speed. The initial design is a planar grating where the beams are free-standing and attached to each other using leaf springs. Actuation is achieved through two electrostatic comb drives at either end of the grating. To prevent deformation of the free-standing grating, the device is 10 μm thick made from a Silicon on Insulator (SOI) wafer in a single mask process. At 100V a periodicity tuning of 3% has been measured. The first resonant mode of the grating is measured at 13.8 kHz, allowing high speed actuation. This combination of wide tunability and high operating speed represents state of the art in the domain of tunable MEMS filters. In order to improve diffraction efficiency and to expand the usable wavelength range, a blazed version of the deformable MEMS grating has been designed. A key issue is maintaining the mechanical properties of the original device while providing optically smooth blazed beams. Using a process based on anisotropic KOH etching, blazed gratings have been obtained and preliminary characterization is promising.

Calibration of High Frequency MEMS Microphones

NASA Technical Reports Server (NTRS)

Shams, Qamar A.; Humphreys, William M.; Bartram, Scott M.; Zuckewar, Allan J.

2007-01-01

Understanding and controlling aircraft noise is one of the major research topics of the NASA Fundamental Aeronautics Program. One of the measurement technologies used to acquire noise data is the microphone directional array (DA). Traditional direction array hardware, consisting of commercially available condenser microphones and preamplifiers can be too expensive and their installation in hard-walled wind tunnel test sections too complicated. An emerging micro-machining technology coupled with the latest cutting edge technologies for smaller and faster systems have opened the way for development of MEMS microphones. The MEMS microphone devices are available in the market but suffer from certain important shortcomings. Based on early experiments with array prototypes, it has been found that both the bandwidth and the sound pressure level dynamic range of the microphones should be increased significantly to improve the performance and flexibility of the overall array. Thus, in collaboration with an outside MEMS design vendor, NASA Langley modified commercially available MEMS microphone as shown in Figure 1 to meet the new requirements. Coupled with the design of the enhanced MEMS microphones was the development of a new calibration method for simultaneously obtaining the sensitivity and phase response of the devices over their entire broadband frequency range. Over the years, several methods have been used for microphone calibration. Some of the common methods of microphone calibration are Coupler (Reciprocity, Substitution, and Simultaneous), Pistonphone, Electrostatic actuator, and Free-field calibration (Reciprocity, Substitution, and Simultaneous). Traditionally, electrostatic actuators (EA) have been used to characterize air-condenser microphones for wideband frequency ranges; however, MEMS microphones are not adaptable to the EA method due to their construction and very small diaphragm size. Hence a substitution-based, free-field method was developed to calibrate these microphones at frequencies up to 80 kHz. The technique relied on the use of a random, ultrasonic broadband centrifugal sound source located in a small anechoic chamber. Phase calibrations of the MEMS microphones were derived from cross spectral phase comparisons between the reference and test substitution microphones and an adjacent and invariant grazing-incidence 1/8-inch standard microphone.

Model-Based Angular Scan Error Correction of an Electrothermally-Actuated MEMS Mirror

PubMed Central

Zhang, Hao; Xu, Dacheng; Zhang, Xiaoyang; Chen, Qiao; Xie, Huikai; Li, Suiqiong

2015-01-01

In this paper, the actuation behavior of a two-axis electrothermal MEMS (Microelectromechanical Systems) mirror typically used in miniature optical scanning probes and optical switches is investigated. The MEMS mirror consists of four thermal bimorph actuators symmetrically located at the four sides of a central mirror plate. Experiments show that an actuation characteristics difference of as much as 4.0% exists among the four actuators due to process variations, which leads to an average angular scan error of 0.03°. A mathematical model between the actuator input voltage and the mirror-plate position has been developed to predict the actuation behavior of the mirror. It is a four-input, four-output model that takes into account the thermal-mechanical coupling and the differences among the four actuators; the vertical positions of the ends of the four actuators are also monitored. Based on this model, an open-loop control method is established to achieve accurate angular scanning. This model-based open loop control has been experimentally verified and is useful for the accurate control of the mirror. With this control method, the precise actuation of the mirror solely depends on the model prediction and does not need the real-time mirror position monitoring and feedback, greatly simplifying the MEMS control system. PMID:26690432

GaAs MOEMS Technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

SPAHN, OLGA B.; GROSSETETE, GRANT D.; CICH, MICHAEL J.

2003-03-01

Many MEMS-based components require optical monitoring techniques using optoelectronic devices for converting mechanical position information into useful electronic signals. While the constituent piece-parts of such hybrid opto-MEMS components can be separately optimized, the resulting component performance, size, ruggedness and cost are substantially compromised due to assembly and packaging limitations. GaAs MOEMS offers the possibility of monolithically integrating high-performance optoelectronics with simple mechanical structures built in very low-stress epitaxial layers with a resulting component performance determined only by GaAs microfabrication technology limitations. GaAs MOEMS implicitly integrates the capability for radiation-hardened optical communications into the MEMS sensor or actuator component, a vitalmore » step towards rugged integrated autonomous microsystems that sense, act, and communicate. This project establishes a new foundational technology that monolithically combines GaAs optoelectronics with simple mechanics. Critical process issues addressed include selectivity, electrochemical characteristics, and anisotropy of the release chemistry, and post-release drying and coating processes. Several types of devices incorporating this novel technology are demonstrated.« less

MEMS Louvers for Thermal Control

NASA Technical Reports Server (NTRS)

Champion, J. L.; Osiander, R.; Darrin, M. A. Garrison; Swanson, T. D.

1998-01-01

Mechanical louvers have frequently been used for spacecraft and instrument thermal control purposes. These devices typically consist of parallel or radial vanes, which can be opened or closed to vary the effective emissivity of the underlying surface. This project demonstrates the feasibility of using Micro-Electromechanical Systems (MEMS) technology to miniaturize louvers for such purposes. This concept offers the possibility of substituting the smaller, lighter weight, more rugged, and less costly MEMS devices for such mechanical louvers. In effect, a smart skin that self adjusts in response to environmental influences could be developed composed of arrays of thousands of miniaturized louvers. Several orders of magnitude size, weight, and volume decreases are potentially achieved using micro-electromechanical techniques. The use of this technology offers substantial benefits in spacecraft/instrument design, integration and testing, and flight operations. It will be particularly beneficial for the emerging smaller spacecraft and instruments of the future. In addition, this MEMS thermal louver technology can form the basis for related spacecraft instrument applications. The specific goal of this effort was to develop a preliminary MEMS device capable of modulating the effective emissivity of radiators on spacecraft. The concept pursued uses hinged panels, or louvers, in a manner such that heat emitted from the radiators is a function of louver angle. An electrostatic comb drive or other such actuator can control the louver position. The initial design calls for the louvers to be gold coated while the underlying surface is of high emissivity. Since, the base MEMS material, silicon, is transparent in the InfraRed (IR) spectrum, the device has a minimum emissivity when closed and a maximum emissivity when open. An initial set of polysilicon louver devices was designed at the Johns Hopkins Applied Physics Laboratory in conjunction with the Thermal Engineering Branch at NASA's Goddard Space Flight Center.

From magic to technology: materials integration by wafer bonding

NASA Astrophysics Data System (ADS)

Dragoi, Viorel

2006-02-01

Wafer bonding became in the last decade a very powerful technology for MEMS/MOEMS manufacturing. Being able to offer a solution to overcome some problems of the standard processes used for materials integration (e.g. epitaxy, thin films deposition), wafer bonding is nowadays considered an important item in the MEMS engineer toolbox. Different principles governing the wafer bonding processes will be reviewed in this paper. Various types of applications will be presented as examples.

On-Orbit, Immuno-Based, Label-Free White Blood Cell Counting System with Microelectromechanical Sensor Technology (OILWBCS-MEMS)

NASA Technical Reports Server (NTRS)

Edmonds, Jessica

2015-01-01

Aurora Flight Sciences, in partnership with Draper Laboratory, has developed a miniaturized system to count white blood cells in microgravity environments. The system uses MEMS technology to simultaneously count total white blood cells, the five white blood cell differential subgroups, and various lymphocyte subtypes. The OILWBCS-MEMS detection technology works by immobilizing an array of white blood cell-specific antibodies on small, gold-coated membranes. When blood flows across the membranes, specific cells' surface protein antigens bind to their corresponding antibodies. This binding can be measured and correlated to cell counts. In Phase I, the partners demonstrated surface chemistry sensitivity and specificity for total white blood cells and two lymphocyte subtypes. In Phase II, a functional prototype demonstrated end-to-end operation. This rugged, miniaturized device requires minimal blood sample preparation and will be useful for both space flight and terrestrial applications.

Ultra-Tunable Micro-Power Converters

DTIC Science & Technology

2008-12-01

These advantages come at the expense of potentially difficult to integrate magnetic materials and magnetic property limitations/losses that may...that add greatly to the size/weight of a system (or whose properties /efficiency may be compromised to accommodate space constraints). Given the...thin film magnetic core (such as NiFe ). “Taps” are periodically provided through a series of microelectromechanical (MEMS) switches. In the example

Scalloping minimization in deep Si etching on Unaxis DSE tools

NASA Astrophysics Data System (ADS)

Lai, Shouliang; Johnson, Dave J.; Westerman, Russ J.; Nolan, John J.; Purser, David; Devre, Mike

2003-01-01

Sidewall smoothness is often a critical requirement for many MEMS devices, such as microfludic devices, chemical, biological and optical transducers, while fast silicon etch rate is another. For such applications, the time division multiplex (TDM) etch processes, so-called "Bosch" processes are widely employed. However, in the conventional TDM processes, rough sidewalls result due to scallop formation. To date, the amplitude of the scalloping has been directly linked to the silicon etch rate. At Unaxis USA Inc., we have developed a proprietary fast gas switching technique that is effective for scalloping minimization in deep silicon etching processes. In this technique, process cycle times can be reduced from several seconds to as little as a fraction of second. Scallop amplitudes can be reduced with shorter process cycles. More importantly, as the scallop amplitude is progressively reduced, the silicon etch rate can be maintained relatively constant at high values. An optimized experiment has shown that at etch rate in excess of 7 μm/min, scallops with length of 116 nm and depth of 35 nm were obtained. The fast gas switching approach offers an ideal manufacturing solution for MEMS applications where extremely smooth sidewall and fast etch rate are crucial.

Wavefront Correction for Large, Flexible Antenna Reflector

NASA Technical Reports Server (NTRS)

Imbriale, William A.; Jammejad, Vahraz; Rajagopalan, Harish; Xu, Shenheng

2010-01-01

A wavefront-correction system has been proposed as part of an outer-space radio communication system that would include a large, somewhat flexible main reflector antenna, a smaller subreflector antenna, and a small array feed at the focal plane of these two reflector antennas. Part of the wavefront-correction system would reside in the subreflector, which would be a planar patch-element reflectarray antenna in which the phase shifts of the patch antenna elements would be controlled via microelectromechanical systems (MEMS) radio -frequency (RF) switches. The system would include the following sensing-and-computing subsystems: a) An optical photogrammetric subsystem built around two cameras would estimate geometric distortions of the main reflector; b) A second subsystem would estimate wavefront distortions from amplitudes and phases of signals received by the array feed elements; and c) A third subsystem, built around small probes on the subreflector plane, would estimate wavefront distortions from differences among phases of signals received by the probes. The distortion estimates from the three subsystems would be processed to generate control signals to be fed to the MEMS RF switches to correct for the distortions, thereby enabling collimation and aiming of the received or transmitted radio beam to the required precision.

Flexible Packaging by Film-Assisted Molding for Microintegration of Inertia Sensors

PubMed Central

Hera, Daniel; Berndt, Armin; Günther, Thomas; Schmiel, Stephan; Harendt, Christine; Zimmermann, André

2017-01-01

Packaging represents an important part in the microintegration of sensors based on microelectromechanical system (MEMS). Besides miniaturization and integration density, functionality and reliability in combination with flexibility in packaging design at moderate costs and consequently high-mix, low-volume production are the main requirements for future solutions in packaging. This study investigates possibilities employing printed circuit board (PCB-)based assemblies to provide high flexibility for circuit designs together with film-assisted transfer molding (FAM) to package sensors. The feasibility of FAM in combination with PCB and MEMS as a packaging technology for highly sensitive inertia sensors is being demonstrated. The results prove the technology to be a viable method for damage-free packaging of stress- and pressure-sensitive MEMS. PMID:28653992

Design, Simulation and Fabrication of Triaxial MEMS High Shock Accelerometer.

PubMed

Zhang, Zhenhai; Shi, Zhiguo; Yang, Zhan; Xie, Zhihong; Zhang, Donghong; Cai, De; Li, Kejie; Shen, Yajing

2015-04-01

On the basis of analyzing the disadvantage of other structural accelerometer, three-axis high g MEMS piezoresistive accelerometer was put forward in order to apply to the high-shock test field. The accelerometer's structure and working principle were discussed in details. The simulation results show that three-axis high shock MEMS accelerometer can bear high shock. After bearing high shock impact in high-shock shooting test, three-axis high shock MEMS accelerometer can obtain the intact metrical information of the penetration process and still guarantee the accurate precision of measurement in high shock load range, so we can not only analyze the law of stress wave spreading and the penetration rule of the penetration process of the body of the missile, but also furnish the testing technology of the burst point controlling. The accelerometer has far-ranging application in recording the typical data that projectile penetrating hard target and furnish both technology guarantees for penetration rule and defend engineering.

MEMS-based thin-film fuel cells

DOEpatents

Jankowksi, Alan F.; Morse, Jeffrey D.

2003-10-28

A micro-electro-mechanical systems (MEMS) based thin-film fuel cells for electrical power applications. The MEMS-based fuel cell may be of a solid oxide type (SOFC), a solid polymer type (SPFC), or a proton exchange membrane type (PEMFC), and each fuel cell basically consists of an anode and a cathode separated by an electrolyte layer. Additionally catalyst layers can also separate the electrodes (cathode and anode) from the electrolyte. Gas manifolds are utilized to transport the fuel and oxidant to each cell and provide a path for exhaust gases. The electrical current generated from each cell is drawn away with an interconnect and support structure integrated with the gas manifold. The fuel cells utilize integrated resistive heaters for efficient heating of the materials. By combining MEMS technology with thin-film deposition technology, thin-film fuel cells having microflow channels and full-integrated circuitry can be produced that will lower the operating temperature an will yield an order of magnitude greater power density than the currently known fuel cells.

Stability, Nonlinearity and Reliability of Electrostatically Actuated MEMS Devices

PubMed Central

Zhang, Wen-Ming; Meng, Guang; Chen, Di

2007-01-01

Electrostatic micro-electro-mechanical system (MEMS) is a special branch with a wide range of applications in sensing and actuating devices in MEMS. This paper provides a survey and analysis of the electrostatic force of importance in MEMS, its physical model, scaling effect, stability, nonlinearity and reliability in detail. It is necessary to understand the effects of electrostatic forces in MEMS and then many phenomena of practical importance, such as pull-in instability and the effects of effective stiffness, dielectric charging, stress gradient, temperature on the pull-in voltage, nonlinear dynamic effects and reliability due to electrostatic forces occurred in MEMS can be explained scientifically, and consequently the great potential of MEMS technology could be explored effectively and utilized optimally. A simplified parallel-plate capacitor model is proposed to investigate the resonance response, inherent nonlinearity, stiffness softened effect and coupled nonlinear effect of the typical electrostatically actuated MEMS devices. Many failure modes and mechanisms and various methods and techniques, including materials selection, reasonable design and extending the controllable travel range used to analyze and reduce the failures are discussed in the electrostatically actuated MEMS devices. Numerical simulations and discussions indicate that the effects of instability, nonlinear characteristics and reliability subjected to electrostatic forces cannot be ignored and are in need of further investigation.

Effects of Ohmic Resistance on Dynamic Characteristics and Impedance of Micro/Nano Cantilever Beam resonators

NASA Astrophysics Data System (ADS)

Rezazadeh, Ghader; Keyvani, Aliasghar; Sadeghi, Morteza H.; Bahrami, Manouchehr

2013-06-01

Effects of Ohmic resistance on MEMS/NEMS vibrating structures that have always been dismissed in some situations may cause important changes in resonance properties and impedance parameters of the MEMS/NEMS based circuits. In this paper it is aimed to present a theoretical model to precisely investigate the problem on a simple cantilever-substrate resonator. In this favor the Ohm's current law and charge conservation law have been merged to find a differential Equation for voltage propagation on the beam and because mostly nano structures are expected as the scope of the problem, modified couple stress theory is used to formulate the dynamic motion of the beam. The two governing equations were coupled and both nonlinear that have been solved simultaneously using a Galerkin based state space formulation. The obtained results that are in exact agreement with previous works show that dynamic pull-in voltage, switching time, and impedance of structure as a MEMS capacitor especially in frequencies higher than natural resonance frequency strongly relay on electrical resistance of the beam and substrate material.

Development of Implantable Wireless Sensor Nodes for Animal Husbandry and MedTech Innovation

PubMed Central

Lu, Jian; Zhang, Lan; Zhang, Dapeng; Matsumoto, Sohei; Hiroshima, Hiroshi; Maeda, Ryutaro; Sato, Mizuho; Toyoda, Atsushi; Gotoh, Takafumi; Ohkohchi, Nobuhiro

2018-01-01

In this paper, we report the development, evaluation, and application of ultra-small low-power wireless sensor nodes for advancing animal husbandry, as well as for innovation of medical technologies. A radio frequency identification (RFID) chip with hybrid interface and neglectable power consumption was introduced to enable switching of ON/OFF and measurement mode after implantation. A wireless power transmission system with a maximum efficiency of 70% and an access distance of up to 5 cm was developed to allow the sensor node to survive for a duration of several weeks from a few minutes’ remote charge. The results of field tests using laboratory mice and a cow indicated the high accuracy of the collected biological data and bio-compatibility of the package. As a result of extensive application of the above technologies, a fully solid wireless pH sensor and a surgical navigation system using artificial magnetic field and a 3D MEMS magnetic sensor are introduced in this paper, and the preliminary experimental results are presented and discussed. PMID:29587448

Dual Q-switched laser outputs from a single lasing medium using an intracavity MEMS micromirror array.

PubMed

Bauer, Ralf; Lubeigt, Walter; Uttamchandani, Deepak

2012-09-01

An intracavity array of individually controlled microelectromechanical system scanning micromirrors was used to actively Q-switch a single side-pumped Nd:YAG gain medium. Two equal power independent laser outputs were simultaneously obtained by separate actuation of two adjacent micromirrors with a combined average output power of 125 mW. Pulse durations of 28 ns FWHM at 8.7 kHz repetition frequency and 34 ns FWHM at 7.9 kHz repetition frequency were observed for the two output beams with beam quality factors M2 of 1.2 and 1.1 and peak powers of 253 W and 232 W, respectively.

Human Pulse Wave Measurement by MEMS Electret Condenser Microphone

NASA Astrophysics Data System (ADS)

Nomura, Shusaku; Hanasaka, Yasushi; Ishiguro, Tadashi; Ogawa, Hiroshi

A micro Electret Condenser Microphone (ECM) fabricated by Micro Electro Mechanical System (MEMS) technology was employed as a novel apparatus for human pulse wave measurement. Since ECM frequency response characteristic, i.e. sensitivity, logically maintains a constant level at lower than the resonance frequency (stiffness control), the slightest pressure difference at around 1.0Hz generated by human pulse wave is expected to detect by MEMS-ECM. As a result of the verification of frequency response of MEMS-ECM, it was found that -20dB/dec of reduction in the sensitivity around 1.0Hz was engendered by a high input-impedance amplifier, i.e. the field effect transistor (FET), mounted near MEMS chip for amplifying tiny ECM signal. Therefore, MEMS-ECM is assumed to be equivalent with a differentiation circuit at around human pulse frequency. Introducing compensation circuit, human pulse wave was successfully obtained. In addition, the radial and ulnar artery tracing, and pulse wave velocity measurement at forearm were demonstrated; as illustrating a possible application of this micro device.

SnO2-based memristors and the potential synergies of integrating memristors with MEMS

NASA Astrophysics Data System (ADS)

Zubia, David; Almeida, Sergio; Talukdar, Arka; Mireles, Jose; MacDonald, Eric

2012-06-01

Memristors, usually in the form metal/metal-oxide/metal, have attracted much attention due to their potential application for non-volatile memory. Their simple structure and ease of fabrication make them good candidates for dense memory with projections of 22 terabytes per wafer. Excellent switching times of ~10 ns, memory endurance of >109 cycles, and extrapolated retention times of >10 yrs have been reported. Interestingly, memristors use the migration of ions to change their resistance in response to charge flow, and can therefore measure and remember the amount of current that has flowed. This is similar to many MEMS devices in which the motion of mass is an operating principle of the device. Memristors are also similar to MEMS in the sense that they can both be resistant to radiation effects. Memristors are radiation tolerant since information is stored as a structural change and not as electronic charge. Functionally, a MEMS device's sensitivity to radiation is concomitant to the role that the dielectric layers play in the function of the device. This is due to radiation-induced trapped charge in the dielectrics which can alter device performance and in extreme cases cause failure. Although different material systems have been investigated for memristors, SnO2 has received little attention even though it demonstrates excellent electronic properties and a high resistance to displacement damage from radiation due to a large Frenkel defect energy (7 eV) compared its bandgap (3.6 eV). This talk discusses recent research on SnO2-based memristors and the potential synergies of integrating memristors with MEMS.

Nonlinear dynamic modeling of a V-shaped metal based thermally driven MEMS actuator for RF switches

NASA Astrophysics Data System (ADS)

Bakri-Kassem, Maher; Dhaouadi, Rached; Arabi, Mohamed; Estahbanati, Shahabeddin V.; Abdel-Rahman, Eihab

2018-05-01

In this paper, we propose a new dynamic model to describe the nonlinear characteristics of a V-shaped (chevron) metallic-based thermally driven MEMS actuator. We developed two models for the thermal actuator with two configurations. The first MEMS configuration has a small tip connected to the shuttle, while the second configuration has a folded spring and a wide beam attached to the shuttle. A detailed finite element model (FEM) and a lumped element model (LEM) are proposed for each configuration to completely characterize the electro-thermal and thermo-mechanical behaviors. The nonlinear resistivity of the polysilicon layer is extracted from the measured current-voltage (I-V) characteristics of the actuator and the simulated corresponding temperatures in the FEM model, knowing the resistivity of the polysilicon at room temperature from the manufacture’s handbook. Both developed models include the nonlinear temperature-dependent material properties. Numerical simulations in comparison with experimental data using a dedicated MEMS test apparatus verify the accuracy of the proposed LEM model to represent the complex dynamics of the thermal MEMS actuator. The LEM and FEM simulation results show an accuracy ranging from a maximum of 13% error down to a minimum of 1.4% error. The actuator with the lower thermal load to air that includes a folded spring (FS), also known as high surface area actuator is compared to the actuator without FS, also known as low surface area actuator, in terms of the I-V characteristics, power consumption, and experimental static and dynamic responses of the tip displacement.

The 13th International Conference on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2013)

NASA Astrophysics Data System (ADS)

Mitcheson, Paul; Beeby, Steve

2013-12-01

It is a pleasure to welcome you to The Royal Society in London and the 13th International Conference on Micro- and Nano-Technology for Power Generation and Energy Conversion Applications, or PowerMEMS 2013. The objective of PowerMEMS 2013 is to catalyse innovation in miniature, micro- and nano-scale technologies for power generation and energy conversion. The conference aims to stimulate the exchange of insights and information, and the development of new ideas in the Power MEMS/NEMS field as well as at the meso-scale. It will allow the attendees to interact and network within our multidisciplinary community that includes professionals from many branches of science and engineering. The technical program is led by four invited speakers covering inductive power transfer, chip scale power sources, thermal energy harvesting and implantable biofuel cells. We received 177 abstracts and following a careful reviewing process by the Technical Program Committee a total of 137 papers were selected for presentation. These have been organised into 16 oral sessions in two parallel streams and two poster sessions that have been augmented by 10 late news papers. The oral and regular poster papers are, for the first time, being published by the Institute of Physics. We have made every effort to make PowerMEMS 2013 the busiest yet and have included for the first time the PowerMEMS School. This two-day school held at Imperial College London covered a wide range of power-MEMS topics including technologies for power generation, power transmission, energy storage, power electronics interfaces and metrology. Registrations for the School exceeded our expectations and it was full by early November. We hope this, and other activities such as the Discussion Panel and the inclusion of late news papers, will make PowerMEMS 2013 a memorable success. We have also reached out to new communities, such as those working in wireless power transfer and RF harvesting to broaden the technology remit of our conference. The social program is an important aspect of any conference and the PowerMEMS 2013 banquet will be held in the Science Museum. This provides a fantastic opportunity to network whilst viewing some of the fundamental engineering innovations that have ultimately bought us all here today. There is a long list of individuals we would like to thank for their support in organising PowerMEMS 2013. Once again the TPC, chaired by Eric Yeatman and Douglas Paul, have given us their valuable time and effort in reviewing abstracts. The PowerMEMS School chairs Einar Halvorsen and Shad Roundy and the expert speakers made the School possible. The local organising committee, led by Alwyn Elliott, have provided us with invaluable assistance in making PowerMEMS 2013 happen. The financial support from Imperial College London, the University of Southampton and conference sponsors has also been gratefully appreciated. Finally, we would like to thank you all for attending and helping in making PowerMEMS 2013 a success. We wish you a productive and enjoyable conference and a wonderful stay in London. Paul Mitcheson and Steve Beeby CONFERENCE OFFICIALS Conference Co-Chairs Stephen Beeby, University of Southampton, UK Paul Mitcheson, Imperial College London, UK Technical Program Committee Co-Chairs Douglas Paul, University of Glasgow, UK Eric Yeatman, Imperial College London, UK PowerMEMS School Co Chairs Einar Halvorsen, Vestfold University College, Norway Shad Roundy, University of Utah, USA Local Organising Committee Chair Alwyn Elliott, Imperial College London, UK International Steering Committee Mark Allen, Georgia Institute of Technology, USA Steve Beeby, University of Southampton, UK Young-Ho Cho, KAIST, South Korea Alan Epstein, Massachusetts Institute of Technology, USA Masayoshi Esashi, Tohoku University, Japan Luc Fréchette, Université de Sherbrooke, Canada Reza Ghodssi, University of Maryland, USA Hiroki Kuwano, Tohoku University, Japan Jeff Lang, Massachusetts Institute of Technology, USA Ryutaro Maeda, National Institute of Advanced Industrial Science and Technology, Japan Kazusuke Maenaka, University of Hyogo, Japan Paul Mitcheson, Imperial College London, UK Albert Pisano, UC San Diego, USA Susumu Sugiyama, Ritsumeikan University, Japan Yuju Suzuki, University of Tokyo, Japan Shuji Tanaka, Tohoku University, Japan Miwako Waga, Susano Berkeley LLC, Japan Peter Woias, University Freiburg IMTEK, Germany Technical Program Committee David Arnold, University of Florida, USA Seiji Aoyagi, Kansai University, Japan Skandar Basrour, Tima Laboratory, France Philippe Basset, Université Paris Est/ESIEE Paris, France Mustafa Ilker Beyaz, Antalya International University, Turkey Danick Briand, École Polytechnique Fédérale de Lausanne (EPFL), Switzerland Steve Burrow, University of Bristol, UK Luc Fréchette, University of Sherbrooke, Canada Takayuki Fujita, University of Hyogo, Japan Florian Herrault, Georgia Institute of Technology, USA Andrew Holmes, Imperial College London, UK Hanseup Kim, University of Utah, USA Seong-Hyok Kim, Georgia Institute of Technology, USA Sejin Kwon, KAIST, South Korea Carol Livermore, Northeastern University, USA Matthew McCarthy, Drexel University, USA Jae Park, Kwangwoon University, South Korea Paul Ronney, University of Southern California, USA Nico de Rooij, École Polytechnique Fédérale de Lausanne (EPFL), Switzerland Yuji Suzuki, University of Tokyo, Japan Shuji Tanaka, Tohoku University, Japan Luis Velasque-Garcia, Massachusetts Institute of Technology, USA Huib Visser, Imec Netherlands Ruud Vullers, Imec, Netherlands C Mike Waits, US Army Research Laboratory, USA Xiaohong Wang, Tsinghua University, China David Yates, Imperial College London, UK Local Organising Committee Dibin Zhu, University of Southampton, UK Alex Weddell, University of Southampton, UK Tzern Toh, Imperial College London, UK Michail Kiziroglou, Imperial College London, UK Christopher Kwan, Imperial College London, UK

Haptic Technologies for MEMS Design

NASA Astrophysics Data System (ADS)

Calis, Mustafa; Desmulliez, Marc P. Y.

2006-04-01

This paper presents for the first time a design methodology for MEMS/NEMS based on haptic sensing technologies. The software tool created as a result of this methodology will enable designers to model and interact in real time with their virtual prototype. One of the main advantages of haptic sensing is the ability to bring unusual microscopic forces back to the designer's world. Other significant benefits for developing such a methodology include gain productivity and the capability to include manufacturing costs within the design cycle.

Novel ultra-lightweight and high-resolution MEMS x-ray optics

NASA Astrophysics Data System (ADS)

Mitsuishi, Ikuyuki; Ezoe, Yuichiro; Takagi, Utako; Mita, Makoto; Riveros, Raul; Yamaguchi, Hitomi; Kato, Fumiki; Sugiyama, Susumu; Fujiwara, Kouzou; Morishita, Kohei; Nakajima, Kazuo; Fujihira, Shinya; Kanamori, Yoshiaki; Yamasaki, Noriko Y.; Mitsuda, Kazuhisa; Maeda, Ryutaro

2009-05-01

We have been developing ultra light-weight X-ray optics using MEMS (Micro Electro Mechanical Systems) technologies.We utilized crystal planes after anisotropic wet etching of silicon (110) wafers as X-ray mirrors and succeeded in X-ray reflection and imaging. Since we can etch tiny pores in thin wafers, this type of optics can be the lightest X-ray telescope. However, because the crystal planes are alinged in certain directions, we must approximate ideal optical surfaces with flat planes, which limits angular resolution of the optics on the order of arcmin. In order to overcome this issue, we propose novel X-ray optics based on a combination of five recently developed MEMS technologies, namely silicon dry etching, X-ray LIGA, silicon hydrogen anneal, magnetic fluid assisted polishing and hot plastic deformation of silicon. In this paper, we describe this new method and report on our development of X-ray mirrors fabricated by these technologies and X-ray reflection experiments of two types of MEMS X-ray mirrors made of silicon and nickel. For the first time, X-ray reflections on these mirrors were detected in the angular response measurements. Compared to model calculations, surface roughness of the silicon and nickel mirrors were estimated to be 5 nm and 3 nm, respectively.

Advanced Exploration Technologies: Micro and Nano Technologies Enabling Space Missions in the 21st Century

NASA Technical Reports Server (NTRS)

Krabach, Timothy

1998-01-01

Some of the many new and advanced exploration technologies which will enable space missions in the 21st century and specifically the Manned Mars Mission are explored in this presentation. Some of these are the system on a chip, the Computed-Tomography imaging Spectrometer, the digital camera on a chip, and other Micro Electro Mechanical Systems (MEMS) technology for space. Some of these MEMS are the silicon micromachined microgyroscope, a subliming solid micro-thruster, a micro-ion thruster, a silicon seismometer, a dewpoint microhygrometer, a micro laser doppler anemometer, and tunable diode laser (TDL) sensors. The advanced technology insertion is critical for NASA to decrease mass, volume, power and mission costs, and increase functionality, science potential and robustness.

Feasibility of Frequency-Modulated Wireless Transmission for a Multi-Purpose MEMS-Based Accelerometer

PubMed Central

Sabato, Alessandro; Feng, Maria Q.

2014-01-01

Recent advances in the Micro Electro-Mechanical System (MEMS) technology have made wireless MEMS accelerometers an attractive tool for Structural Health Monitoring (SHM) of civil engineering structures. To date, sensors' low sensitivity and accuracy—especially at very low frequencies—have imposed serious limitations for their application in monitoring large-sized structures. Conventionally, the MEMS sensor's analog signals are converted to digital signals before radio-frequency (RF) wireless transmission. The conversion can cause a low sensitivity to the important low-frequency and low-amplitude signals. To overcome this difficulty, the authors have developed a MEMS accelerometer system, which converts the sensor output voltage to a frequency-modulated signal before RF transmission. This is achieved by using a Voltage to Frequency Conversion (V/F) instead of the conventional Analog to Digital Conversion (ADC). In this paper, a prototype MEMS accelerometer system is presented, which consists of a transmitter and receiver circuit boards. The former is equipped with a MEMS accelerometer, a V/F converter and a wireless RF transmitter, while the latter contains an RF receiver and a F/V converter for demodulating the signal. The efficacy of the MEMS accelerometer system in measuring low-frequency and low-amplitude dynamic responses is demonstrated through extensive laboratory tests and experiments on a flow-loop pipeline. PMID:25198003

Feasibility of frequency-modulated wireless transmission for a multi-purpose MEMS-based accelerometer.

PubMed

Sabato, Alessandro; Feng, Maria Q

2014-09-05

Recent advances in the Micro Electro-Mechanical System (MEMS) technology have made wireless MEMS accelerometers an attractive tool for Structural Health Monitoring (SHM) of civil engineering structures. To date, sensors' low sensitivity and accuracy--especially at very low frequencies--have imposed serious limitations for their application in monitoring large-sized structures. Conventionally, the MEMS sensor's analog signals are converted to digital signals before radio-frequency (RF) wireless transmission. The conversion can cause a low sensitivity to the important low-frequency and low-amplitude signals. To overcome this difficulty, the authors have developed a MEMS accelerometer system, which converts the sensor output voltage to a frequency-modulated signal before RF transmission. This is achieved by using a Voltage to Frequency Conversion (V/F) instead of the conventional Analog to Digital Conversion (ADC). In this paper, a prototype MEMS accelerometer system is presented, which consists of a transmitter and receiver circuit boards. The former is equipped with a MEMS accelerometer, a V/F converter and a wireless RF transmitter, while the latter contains an RF receiver and a F/V converter for demodulating the signal. The efficacy of the MEMS accelerometer system in measuring low-frequency and low-amplitude dynamic responses is demonstrated through extensive laboratory tests and experiments on a flow-loop pipeline.

Surface-micromachined and high-aspect ratio electrostatic actuators for aeronautic and space applications: design and lifetime considerations

NASA Astrophysics Data System (ADS)

Vescovo, P.; Joseph, E.; Bourbon, G.; Le Moal, P.; Minotti, P.; Hibert, C.; Pont, G.

2003-09-01

This paper focuses on recent advances in the field of MEMS-based actuators and distributed microelectromechanical systems (MEMS). IC-processed actuators (e.g. actuators that are machined using integrated circuit batch processes) are expected to open a wide range of industrial applications on the near term. The most promising investigations deal with high-aspect ratio electric field driven microactuators suitable for use in numerous technical fields such as aeronautics and space industry. Because the silicon micromachining technology have the potential to integrate both mechanical components and control circuits within a single process, MEMS-based active control of microscopic and macroscopic structures appears to be one of the most promising challenges for the next decade. As a first step towards new generations of MEMS-based smart structures, recent investigations dealing with silicon mechanisms involving MEMS-based actuators are briefly discussed in this paper.

MEMS reliability: coming of age

NASA Astrophysics Data System (ADS)

Douglass, Michael R.

2008-02-01

In today's high-volume semiconductor world, one could easily take reliability for granted. As the MOEMS/MEMS industry continues to establish itself as a viable alternative to conventional manufacturing in the macro world, reliability can be of high concern. Currently, there are several emerging market opportunities in which MOEMS/MEMS is gaining a foothold. Markets such as mobile media, consumer electronics, biomedical devices, and homeland security are all showing great interest in microfabricated products. At the same time, these markets are among the most demanding when it comes to reliability assurance. To be successful, each company developing a MOEMS/MEMS device must consider reliability on an equal footing with cost, performance and manufacturability. What can this maturing industry learn from the successful development of DLP technology, air bag accelerometers and inkjet printheads? This paper discusses some basic reliability principles which any MOEMS/MEMS device development must use. Examples from the commercially successful and highly reliable Digital Micromirror Device complement the discussion.

3-D Printing as an Effective Educational Tool for MEMS Design and Fabrication

ERIC Educational Resources Information Center

Dahle, Reena; Rasel, Rafiul

2016-01-01

This paper presents a series of course modules developed as a high-impact and cost-effective learning tool for modeling and simulating the microfabrication process and design of microelectromechanical systems (MEMS) devices using three-dimensional (3-D) printing. Microfabrication technology is an established fabrication technique for small and…

Urban MEMS based seismic network for post-earthquakes rapid disaster assessment

NASA Astrophysics Data System (ADS)

D'Alessandro, A.; Luzio, D.; D'Anna, G.

2014-09-01

In this paper, we introduce a project for the realization of the first European real-time urban seismic network based on Micro Electro-Mechanical Systems (MEMS) technology. MEMS accelerometers are a highly enabling technology, and nowadays, the sensitivity and the dynamic range of these sensors are such as to allow the recording of earthquakes of moderate magnitude even at a distance of several tens of kilometers. Moreover, thanks to their low cost and smaller size, MEMS accelerometers can be easily installed in urban areas in order to achieve an urban seismic network constituted by high density of observation points. The network is being implemented in the Acireale Municipality (Sicily, Italy), an area among those with the highest hazard, vulnerability and exposure to the earthquake of the Italian territory. The main objective of the implemented urban network will be to achieve an effective system for post-earthquake rapid disaster assessment. The earthquake recorded, also that with moderate magnitude will be used for the effective seismic microzonation of the area covered by the network. The implemented system will be also used to realize a site-specific earthquakes early warning system.

Solid oxide MEMS-based fuel cells

DOEpatents

Jankowksi, Alan F.; Morse, Jeffrey D.

2007-03-13

A micro-electro-mechanical systems (MEMS) based thin-film fuel cells for electrical power applications. The MEMS-based fuel cell may be of a solid oxide type (SOFC), a solid polymer type (SPFC), or a proton exchange membrane type (PEMFC), and each fuel cell basically consists of an anode and a cathode separated by an electrolyte layer. The electrolyte layer can consist of either a solid oxide or solid polymer material, or proton exchange membrane electrolyte materials may be used. Additionally catalyst layers can also separate the electrodes (cathode and anode) from the electrolyte. Gas manifolds are utilized to transport the fuel and oxidant to each cell and provide a path for exhaust gases. The electrical current generated from each cell is drawn away with an interconnect and support structure integrated with the gas manifold. The fuel cells utilize integrated resistive heaters for efficient heating of the materials. By combining MEMS technology with thin-film deposition technology, thin-film fuel cells having microflow channels and full-integrated circuitry can be produced that will lower the operating temperature an will yield an order of magnitude greater power density than the currently known fuel cells.

Solid polymer MEMS-based fuel cells

DOEpatents

Jankowski, Alan F [Livermore, CA; Morse, Jeffrey D [Pleasant Hill, CA

2008-04-22

A micro-electro-mechanical systems (MEMS) based thin-film fuel cells for electrical power applications. The MEMS-based fuel cell may be of a solid oxide type (SOFC), a solid polymer type (SPFC), or a proton exchange membrane type (PEMFC), and each fuel cell basically consists of an anode and a cathode separated by an electrolyte layer. The electrolyte layer can consist of either a solid oxide or solid polymer material, or proton exchange membrane electrolyte materials may be used. Additionally catalyst layers can also separate the electrodes (cathode and anode) from the electrolyte. Gas manifolds are utilized to transport the fuel and oxidant to each cell and provide a path for exhaust gases. The electrical current generated from each cell is drawn away with an interconnect and support structure integrated with the gas manifold. The fuel cells utilize integrated resistive heaters for efficient heating of the materials. By combining MEMS technology with thin-film deposition technology, thin-film fuel cells having microflow channels and full-integrated circuitry can be produced that will lower the operating temperature an will yield an order of magnitude greater power density than the currently known fuel cells.

Review of the potential of a wireless MEMS and TFT microsystems for the measurement of pressure in the GI tract.

PubMed

Arshak, A; Arshak, K; Waldron, D; Morris, D; Korostynska, O; Jafer, E; Lyons, G

2005-06-01

Telemetry capsules have existed since the 1950s and were used to measure temperature, pH or pressure inside the gastrointestinal (GI) tract. It was hoped that these capsules would replace invasive techniques in the diagnosis of function disorders in the GI tract. However, problems such as signal loss and uncertainty of the pills position limited their use in a clinical setting. In this paper, a review of the capabilities of MicroElectroMechanical Systems (MEMS) and thick film technology (TFT) for the fabrication of a wireless pressure sensing microsystem is presented. The circuit requirements and methods of data transfer are examined. The available fabrication methods for MEMS sensors are also discussed and examples of wireless sensors are given. Finally the limitations of each technology are examined.

EDITORIAL: Special issue for papers selected from The 8th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2008) Special issue for papers selected from The 8th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2008)

NASA Astrophysics Data System (ADS)

Tanaka, Shuji

2009-09-01

This special issue of the Journal of Micromechanics and Microengineering features papers selected from The 8th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2008) with the 2nd Symposium on Micro Environmental Machine Systems (μMEMS 2008). The workshop was held in Sendai, Japan on 9-12 November 2008 by Tohoku University. This is the second time that the PowerMEMS workshop has been held in Sendai, following the first workshop in 2000. Power MEMS is one of the newest categories of MEMS, which encompasses microdevices and microsystems for power generation, energy conversion and propulsion. The first concept of Power MEMS was born in the late 1990's from a MEMS-based gas turbine project at Massachusetts Institute of Technology. After that, the research and development of Power MEMS have been promoted by the strong need for compact power sources with high energy and/or power density. Since its inception, Power MEMS has expanded to include not only various MEMS-based power generators but also small energy machines and microdevices for macro power generators. Previously, the main topics of the PowerMEMS workshop were miniaturized gas turbines and micro fuel cells, but recently, energy harvesting has been the hottest topic. In 2008, energy harvesting had a 41% share in the 118 accepted regular papers. This special issue includes 19 papers on various topics. Finally, I would like to express my sincere appreciation to the members of the International Steering Committee, the Technical Program Committee, the Local Organizing Committee and financial supporters. This special issue was edited in collaboration with the staff of IOP Publishing.

Memory flexibility training for autobiographical memory as an intervention for maintaining social and mental well-being in older adults.

PubMed

Leahy, Fiona; Ridout, Nathan; Holland, Carol

2018-05-07

Autobiographical memory specificity (AMS) reduces with increasing age and is associated with depression, social problem-solving and functional limitations. However, ability to switch between general and specific, as well as between positive and negative retrieval, may be more important for the strategic use of autobiographical information in everyday life. Ability to switch between retrieval modes is likely to rely on aspects of executive function. We propose that age-related deficits in cognitive flexibility impair AMS, but the "positivity effect" protects positively valenced memories from impaired specificity. A training programme to improve the ability to flexibly retrieve different types of memories in depressed adults (MemFlex) was examined in non-depressed older adults to determine effects on AMS, valence and the executive functions underlying cognitive flexibility. Thirty-nine participants aged 70+ (MemFlex, n = 20; control, n = 19) took part. AMS and the inhibition aspect of executive function improved in both groups, suggesting these abilities are amenable to change, although not differentially affected by this type of training. Lower baseline inhibition scores correlated with increased negative, but not positive AMS, suggesting that positive AMS is an automatic process in older adults. Changes in AMS correlated with changes in social problem-solving, emphasising the usefulness of AMs in a social environment.

Development, characterization and application of compact spectrometers based on MEMS with in-plane capacitive drives

NASA Astrophysics Data System (ADS)

Kenda, A.; Kraft, M.; Tortschanoff, A.; Scherf, Werner; Sandner, T.; Schenk, Harald; Luettjohann, Stephan; Simon, A.

2014-05-01

With a trend towards the use of spectroscopic systems in various fields of science and industry, there is an increasing demand for compact spectrometers. For UV/VIS to the shortwave near-infrared spectral range, compact hand-held polychromator type devices are widely used and have replaced larger conventional instruments in many applications. Still, for longer wavelengths this type of compact spectrometers is lacking suitable and affordable detector arrays. In perennial development Carinthian Tech Research AG together with the Fraunhofer Institute for Photonic Microsystems endeavor to close this gap by developing spectrometer systems based on photonic MEMS. Here, we review on two different spectrometer developments, a scanning grating spectrometer working in the NIR and a FT-spectrometer accessing the mid-IR range up to 14 μm. Both systems are using photonic MEMS devices actuated by in-plane comb drive structures. This principle allows for high mechanical amplitudes at low driving voltages but results in gratings respectively mirrors oscillating harmonically. Both systems feature special MEMS structures as well as aspects in terms of system integration which shall tease out the best possible overall performance on the basis of this technology. However, the advantages of MEMS as enabling technology for high scanning speed, miniaturization, energy efficiency, etc. are pointed out. Whereas the scanning grating spectrometer has already evolved to a product for the point of sale analysis of traditional Chinese medicine products, the purpose of the FT-spectrometer as presented is to demonstrate what is achievable in terms of performance. Current developments topics address MEMS packaging issues towards long term stability, further miniaturization and usability.

MEMS Actuators for Improved Performance and Durability

NASA Astrophysics Data System (ADS)

Yearsley, James M.

Micro-ElectroMechanical Systems (MEMS) devices take advantage of force-scaling at length scales smaller than a millimeter to sense and interact with directly with phenomena and targets at the microscale. MEMS sensors found in everyday devices like cell-phones and cars include accelerometers, gyros, pressure sensors, and magnetic sensors. MEMS actuators generally serve more application specific roles including micro- and nano-tweezers used for single cell manipulation, optical switching and alignment components, and micro combustion engines for high energy density power generation. MEMS rotary motors are actuators that translate an electric drive signal into rotational motion and can serve as rate calibration inputs for gyros, stages for optical components, mixing devices for micro-fluidics, etc. Existing rotary micromotors suffer from friction and wear issues that affect lifetime and performance. Attempts to alleviate friction effects include surface treatment, magnetic and electrostatic levitation, pressurized gas bearings, and micro-ball bearings. The present work demonstrates a droplet based liquid bearing supporting a rotary micromotor that improves the operating characteristics of MEMS rotary motors. The liquid bearing provides wear-free, low-friction, passive alignment between the rotor and stator. Droplets are positioned relative to the rotor and stator through patterned superhydrophobic and hydrophilic surface coatings. The liquid bearing consists of a central droplet that acts as the motor shaft, providing axial alignment between rotor and stator, and satellite droplets, analogous to ball-bearings, that provide tip and tilt stable operation. The liquid bearing friction performance is characterized through measurement of the rotational drag coefficient and minimum starting torque due to stiction and geometric effects. Bearing operational performance is further characterized by modeling and measuring stiffness, environmental survivability, and high-speed alignment capability. The superhydrophobic coatings developed for droplet containment are also discussed and measurements of contact angle are shown to affect device performance through correlation to models of bearing friction and stiffness.

Quasi-Optical Network Analyzers and High-Reliability RF MEMS Switched Capacitors

NASA Astrophysics Data System (ADS)

Grichener, Alexander

The thesis first presents a 2-port quasi-optical scalar network analyzer consisting of a transmitter and receiver both built in planar technology. The network analyzer is based on a Schottky-diode mixer integrated inside a planar antenna and fed differentially by a CPW transmission line. The antenna is placed on an extended hemispherical high-resistivity silicon substrate lens. The LO signal is swept from 3-5 GHz and high-order harmonic mixing in both up- and down- conversion mode is used to realize the 15-50 GHz RF bandwidth. The network analyzer resulted in a dynamic range of greater than 40 dB and was successfully used to measure a frequency selective surface with a second-order bandpass response. Furthermore, the system was built with circuits and components for easy scaling to millimeter-wave frequencies which is the primary motivation for this work. The application areas for a millimeter and submillimeter-wave network analyzer include material characterization and art diagnostics. The second project presents several RF MEMS switched capacitors designed for high-reliability operation and suitable for tunable filters and reconfigurable networks. The first switched-capacitor resulted in a digital capacitance ratio of 5 and an analog capacitance ratio of 5-9. The analog tuning of the down-state capacitance is enhanced by a positive vertical stress gradient in the the beam, making it ideal for applications that require precision tuning. A thick electroplated beam resulted in Q greater than 100 at C to X-band frequencies, and power handling of 0.6-1.1 W. The design also minimized charging in the dielectric, resulting in excellent reliability performance even under hot-switched and high power (1 W) conditions. The second switched-capacitor was designed without any dielectric to minimize charging. The device was hot-switched at 1 W of RF power for greater than 11 billion cycles with virtually no change in the C-V curve. The final project presents a 7-channel channelizer based on the mammalian cochlea. The cochlea is an amazing channelizing filter, covering three decades of bandwidth with over 3,000 channels in a very small physical space. Using a simplified mechanical cochlear model and its electrical analogue, a design method is demonstrated for RF and microwave channelizers that retains the desirable features of the cochlea including the ability to cascade a large number of channels (for multiple-octave frequency coverage), and a high-order stop-band rejection. A 6-pole response is synthesized in each channel using the top-C coupled topology. A constant absolute 3 dB bandwidth of around 4.3 MHz and an insertion loss of around 3.9 dB is measured in each channel. A high isolation (greater than 35 dB) is achieved between adjacent channels. A reflection loss of greater than 15 dB is measured at the input port over the entire channelizer bandwidth. Application areas for the demonstrated channelizer include wideband, contiguous-channel receivers for signal intelligence or spectral analysis.

Advanced Measurement Systems Available to PIWG Members

NASA Technical Reports Server (NTRS)

Anderson, Robert; Lei, Jih-Fen (Technical Monitor)

2002-01-01

It was developed advanced measurement technologies to meet NASA goals: reduce design cycle time, reduce emission, reduce testing time, increase safety. The technology are saving money. This technology are available now for technology transfer: optical diagnostics, the film technology and MEMS devices.

Applications of Digital Micromirror Devices to Astronomical Instrumentation

NASA Astrophysics Data System (ADS)

Robberto, M.

MEMS devices are among the major technological breakthroughs of the last two decades. Besides finding widespread use in high-tech and consumer market electronics, MEMS enable new types of astronomical instruments. I concentrate on Digital Micromirror Devices, which have been already adopted in astronomy and can enable scientific investigations that would otherwise remain beyond our technical capabilities.

MEMSlab: A Practical MEMS Course for the Fabrication, Packaging, and Testing of a Single-Axis Accelerometer

ERIC Educational Resources Information Center

Grundbacher, R.; Hoetzel, J. E.; Hierold, C.

2009-01-01

A microelectro-mechanical systems (MEMS) laboratory course (MEMSlab) in the Mechanical and Process Engineering Department at the Swiss Federal Institute of Technology (ETH Zurich), is presented. The course has been taught for four years and has been attended primarily by Master's students from mechanical and electrical engineering; since fall…

Flexible Chip Scale Package and Interconnect for Implantable MEMS Movable Microelectrodes for the Brain

PubMed Central

Jackson, Nathan; Muthuswamy, Jit

2009-01-01

We report here a novel approach called MEMS microflex interconnect (MMFI) technology for packaging a new generation of Bio-MEMS devices that involve movable microelectrodes implanted in brain tissue. MMFI addresses the need for (i) operating space for movable parts and (ii) flexible interconnects for mechanical isolation. We fabricated a thin polyimide substrate with embedded bond-pads, vias, and conducting traces for the interconnect with a backside dry etch, so that the flexible substrate can act as a thin-film cap for the MEMS package. A double gold stud bump rivet bonding mechanism was used to form electrical connections to the chip and also to provide a spacing of approximately 15–20 µm for the movable parts. The MMFI approach achieved a chip scale package (CSP) that is lightweight, biocompatible, having flexible interconnects, without an underfill. Reliability tests demonstrated minimal increases of 0.35 mΩ, 0.23 mΩ and 0.15 mΩ in mean contact resistances under high humidity, thermal cycling, and thermal shock conditions respectively. High temperature tests resulted in an increase in resistance of > 90 mΩ when aluminum bond pads were used, but an increase of ~ 4.2 mΩ with gold bond pads. The mean-time-to-failure (MTTF) was estimated to be at least one year under physiological conditions. We conclude that MMFI technology is a feasible and reliable approach for packaging and interconnecting Bio-MEMS devices. PMID:20160981

Ultra-compact MEMS FTIR spectrometer

NASA Astrophysics Data System (ADS)

Sabry, Yasser M.; Hassan, Khaled; Anwar, Momen; Alharon, Mohamed H.; Medhat, Mostafa; Adib, George A.; Dumont, Rich; Saadany, Bassam; Khalil, Diaa

2017-05-01

Portable and handheld spectrometers are being developed and commercialized in the late few years leveraging the rapidly-progressing technology and triggering new markets in the field of on-site spectroscopic analysis. Although handheld devices were commercialized for the near-infrared spectroscopy (NIRS), their size and cost stand as an obstacle against the deployment of the spectrometer as spectral sensing components needed for the smart phone industry and the IoT applications. In this work we report a chip-sized microelectromechanical system (MEMS)-based FTIR spectrometer. The core optical engine of the solution is built using a passive-alignment integration technique for a selfaligned MEMS chip; self-aligned microoptics and a single detector in a tiny package sized about 1 cm3. The MEMS chip is a monolithic, high-throughput scanning Michelson interferometer fabricated using deep reactive ion etching technology of silicon-on-insulator substrate. The micro-optical part is used for conditioning the input/output light to/from the MEMS and for further light direction to the detector. Thanks to the all-reflective design of the conditioning microoptics, the performance is free of chromatic aberration. Complemented by the excellent transmission properties of the silicon in the infrared region, the integrated solution allows very wide spectral range of operation. The reported sensor's spectral resolution is about 33 cm-1 and working in the range of 1270 nm to 2700 nm; upper limited by the extended InGaAs detector. The presented solution provides a low cost, low power, tiny size, wide wavelength range NIR spectral sensor that can be manufactured with extremely high volumes. All these features promise the compatibility of this technology with the forthcoming demand of smart portable and IoT devices.

PREFACE: 14th International Conference on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2014)

NASA Astrophysics Data System (ADS)

2014-11-01

It is our great pleasure to welcome you to the 14th International Conference on Micro- and Nano-Technology for Power Generation and Energy Conversion Applications, or PowerMEMS 2014, in Awaji Island, Japan. The aim of PowerMEM is to present the latest research results in the field of miniature, micro- and nano-scale technologies for power generation and energy conversion. The conference will also- give us the opportunity to exchange informations and new ideas in the field of Power MEMS/NEMS. The current status of the field of PowerMEMS spans the full spectrum from basic research to practical applications. We will enjoy valuable discussions not only from the viewpoint of academia but from commercial and industrial perspectives. In the conference, three invited speakers lead the technical program. We received 172 abstracts and after a careful reviewing process by the Technical Program Committee a total of 133 papers were selected for presentation. These have been organized into 16 Oral sessions in two parallel streams and two poster sessions including some late-news papers. The oral and regular poster papers are published by the Institute of Physics (IOP). We have also organized a PowerMEMS School in Kobe-Sannomiya contiguous to the main conference. This two-day school will cover various topics of energy harvesting. World leading experts will give invited lectures on their main topics. This is a new experiment to broaden the technology remit of our conference by organizing mini symposiums that aim to gather the latest research on the following topics by the organizers: Microscale Combustion, Wideband Vibration Energy Harvesting, RF Energy Transfer and Industrial Application. We hope this, and other activities will make PowerMEMS2014 a memorable success. One of the important programs in an international conference is the social program, and we prepare the PowerMEMS2014 banquet in the banquet room at the Westin Awaji Island Hotel. This will provide an opportunity to create strong networks between researchers. We also provide nice opportunities to experience Japanese nature and culture. The special cruise to see the magnificent whirlpool up close will definitely be one of the highlights. Additionally, we will serve Awaji's traditional performing art, Awaji Ningyo Joruri, which has a history of over 500 years and has been inherited through the generations. There are many individuals we would like to thank for their support in organizing PowerMEMS2014. The TPC, chaired by Takayuki Fujita, have given us their valuable time and best effort in reviewing abstracts. The PowerMEMS School chair Yuji Suzuki and the expert speakers made the School possible. The local organizing committee, led by Kensuke Kanda has provided us with invaluable assistance in preparing the PowerMEMS2014 venue. The financial support from both the Tsutomu Nakauchi Foundation, the Hyogo International Association and the conference sponsors have also been gratefully appreciated. Finally, we would like to thank each of you for attending the conference and bringing your expertise. We wish you all a successful conference and an exciting and relaxing stay in Awaji Island.

Surface micromachined MEMS deformable mirror based on hexagonal parallel-plate electrostatic actuator

NASA Astrophysics Data System (ADS)

Ma, Wenying; Ma, Changwei; Wang, Weimin

2018-03-01

Deformable mirrors (DM) based on microelectromechanical system (MEMS) technology are being applied in adaptive optics (AO) system for astronomical telescopes and human eyes more and more. In this paper a MEMS DM with hexagonal actuator is proposed and designed. The relationship between structural design and performance parameters, mainly actuator coupling, is analyzed carefully and calculated. The optimum value of actuator coupling is obtained. A 7-element DM prototype is fabricated using a commercial available standard three-layer polysilicon surface multi-user-MEMS-processes (PolyMUMPs). Some key performances, including surface figure and voltage-displacement curve, are measured through a 3D white light profiler. The measured performances are very consistent with the theoretical values. The proposed DM will benefit the miniaturization of AO systems and lower their cost.

Review of Polyimides Used in the Manufacturing of Micro Systems

NASA Technical Reports Server (NTRS)

Wilson, William C.; Atkinson, Gary M.

2007-01-01

Since their invention, polyimides have found numerous uses in MicroElectroMechanical Systems (MEMS) technology. Polyimides can act as photoresist, sacrificial layers, structural layers, and even as a replacement for silicon as the substrate during MEMS fabrication. They enable fabrication of both low and high aspect ratio devices. Polyimides have been used to fabricate expendable molds and reusable flexible molds. Development of a variety of devices that employ polyimides for sensor applications has occurred. Micro-robotic actuator applications include hinges, thermal actuators and residual stress actuators. Currently, polyimides are being used to create new sensors and devices for aerospace applications. This paper presents a review of some of the many uses of polyimides in the development of MEMS devices, including a new polyimide based MEMS fabrication process.

Evolution from MEMS-based Linear Drives to Bio-based Nano Drives

NASA Astrophysics Data System (ADS)

Fujita, Hiroyuki

The successful extension of semiconductor technology to fabricate mechanical parts of the sizes from 10 to 100 micrometers opened wide ranges of possibilities for micromechanical devices and systems. The fabrication technique is called micromachining. Micromachining processes are based on silicon integrated circuits (IC) technology and used to build three-dimensional structures and movable parts by the combination of lithography, etching, film deposition, and wafer bonding. Microactuators are the key devices allowing MEMS to perform physical functions. Some of them are driven by electric, magnetic, and fluidic forces. Some others utilize actuator materials including piezoelectric (PZT, ZnO, quartz) and magnetostrictive materials (TbFe), shape memory alloy (TiNi) and bio molecular motors. This paper deals with the development of MEMS based microactuators, especially linear drives, following my own research experience. They include an electrostatic actuator, a superconductive levitated actuator, arrayed actuators, and a bio-motor-driven actuator.

MEMS- and LC-adaptive optics at the Naval Research Laboratory

NASA Astrophysics Data System (ADS)

Restaino, S. R.; Wilcox, C. C.; Martinez, T.; Andrews, J. R.; Santiago, F.; Payne, D. M.

2012-06-01

Adaptive Optics (AO) is an ensemble of techniques that aims at the remedial of the deleterious effects that the Earth's turbulent atmosphere induces on both imagery and signal gathering in real time. It has been over four decades since the first AO system was developed and tested. During this time important technological advances have changed profoundly the way that we think and develop AO systems. The use of Micro-Electro-Mechanical-Systems (MEMS) devices and Liquid Crystal Devices (LCD) has revolutionized these technologies making possible to go from very expensive, very large and power consuming systems to very compact and inexpensive systems. These changes have rendered AO systems useful and applicable in other fields ranging from medical imaging to industry. In this paper we will review the research efforts at the Naval research Laboratory (NRL) to develop AO systems based on both MEMs and LCD in order to produce more compact and light weight AO systems.

Characterization of shape and deformation of MEMS by quantitative optoelectronic metrology techniques

NASA Astrophysics Data System (ADS)

Furlong, Cosme; Pryputniewicz, Ryszard J.

2002-06-01

Recent technological trends based on miniaturization of mechanical, electro-mechanical, and photonic devices to the microscopic scale, have led to the development of microelectromechanical systems (MEMS). Effective development of MEMS components requires the synergism of advanced design, analysis, and fabrication methodologies, and also of quantitative metrology techniques for characterizing their performance, reliability, and integrity during the electronic packaging cycle. In this paper, we describe opto-electronic techniques for measuring, with sub-micrometer accuracy, shape and changes in states of deformation of MEMS strictures. With the described opto-electronic techniques, it is possible to characterize MEMS components using the display and data modes. In the display mode, interferometric information related to shape and deformation is displayed at video frame rates, providing the capability for adjusting and setting experimental conditions. In the data mode, interferometric information related to shape and deformation is recorded as high-spatial and high-digital resolution images, which are further processed to provide quantitative 3D information. Furthermore, the quantitative 3D data are exported to computer-aided design (CAD) environments and utilized for analysis and optimization of MEMS devices. Capabilities of opto- electronic techniques are illustrated with representative applications demonstrating their applicability to provide indispensable quantitative information for the effective development and optimization of MEMS devices.

MEMS-based IR-sources

NASA Astrophysics Data System (ADS)

Weise, Sebastian; Steinbach, Bastian; Biermann, Steffen

2016-03-01

The series JSIR350 sources are MEMS based infrared emitters. These IR sources are characterized by a high radiation output. Thus, they are excellent for NDIR gas analysis and are ideally suited for using with our pyro-electric or thermopile detectors. The MEMS chips used in Micro-Hybrid's infrared emitters consist of nano-amorphous carbon (NAC). The MEMS chips are produced in the USA. All Micro-Hybrid Emitter are designed and specified to operate up to 850°C. The improvements we have made in the source's packaging enable us to provide IR sources with the best performance on the market. This new technology enables us to seal the housings of infrared radiation sources with soldered infrared filters or windows and thus cause the parts to be impenetrable to gases. Micro-Hybrid provide various ways of adapting our MEMS based infrared emitter JSIR350 to customer specifications, like specific burn-in parameters/characteristic, different industrial standard housings, producible with customized cap, reflector or pin-out.

Gas detection with microelectromechanical Fabry-Perot interferometer technology in cell phone

NASA Astrophysics Data System (ADS)

Mannila, Rami; Hyypiö, Risto; Korkalainen, Marko; Blomberg, Martti; Kattelus, Hannu; Rissanen, Anna

2015-06-01

VTT Technical Research Centre of Finland has developed a miniaturized optical sensor for gas detection in a cell phone. The sensor is based on a microelectromechanical (MEMS) Fabry-Perot interferometer, which is a structure with two highly reflective surfaces separated by a tunable air gap. The MEMS FPI is a monolithic device, i.e. it is made entirely on one substrate in a batch process, without assembling separate pieces together. The gap is adjusted by moving the upper mirror with electrostatic force, so there are no actual moving parts. VTT has designed and manufactured a MEMS FPI based carbon dioxide sensor demonstrator which is integrated to a cell phone shield cover. The demonstrator contains light source, gas cell, MEMS FPI, detector, control electronics and two coin cell batteries as a power source. It is connected to the cell phone by Bluetooth. By adjusting the wavelength range and customizing the MEMS FPI structure, it is possible to selectively sense multiple gases.

MEMS-based tunable gratings and their applications

NASA Astrophysics Data System (ADS)

Yu, Yiting; Yuan, Weizheng; Qiao, Dayong

2015-03-01

The marriage of optics and MEMS has resulted in a new category of optical devices and systems that have unprecedented advantages compared with their traditional counterparts. As an important spatial light modulating technology, diffractive optical MEMS obtains a wide variety of successful commercial applications, e.g. projection displays, optical communication and spectral analysis, due to its features of highly compact, low-cost, IC-compatible, excellent performance, and providing possibilities for developing totally new, yet smart devices and systems. Three most successful MEMS diffraction gratings (GLVs, Polychromator and DMDs) are briefly introduced and their potential applications are analyzed. Then, three different MEMS tunable gratings developed by our group, named as micro programmable blazed gratings (μPBGs) and micro pitch-tunable gratings (μPTGs) working in either digital or analog mode, are demonstrated. The strategies to largely enhance the maximum blazed angle and grating period are described. Some preliminary application explorations based on the developed grating devices are also shown. For our ongoing research focus, we will further improve the device performance to meet the engineering application requirements.

MEMS Stirling Cooler Development Update

NASA Technical Reports Server (NTRS)

Moran, Matthew E.; Wesolek, Danielle

2003-01-01

This presentation provides an update on the effort to build and test a prototype unit of the patented MEMS Stirling cooler concept. A micro-scale regenerator has been fabricated by Polar Thermal Technologies and is currently being integrated into a Stirling cycle simulator at Johns Hopkins University Applied Physics Laboratory. A discussion of the analysis, design, assembly, and test plans for the prototype will be presented.

ARPA-NRL Laser Program - Semiannual Technical Report to Defense Advanced Research Projects Agency, 1 January 1974-30 June 1974

DTIC Science & Technology

1975-04-01

high voltage pulse with an individual mode-locked laser pulse. The switching system was tested using the arrangc- mem shown in fig. 2. The output of...v-0)-f COU-I) 1- 2 10 C^ OHP (p ^ % cP o o ^ o o o .03 .00 .12 .14 „-1/3 .L .16 .18 .20 .22 T (0K) Fl8 + 3m^mr

A large-area wireless power-transmission sheet using printed organic transistors and plastic MEMS switches.

PubMed

Sekitani, Tsuyoshi; Takamiya, Makoto; Noguchi, Yoshiaki; Nakano, Shintaro; Kato, Yusaku; Sakurai, Takayasu; Someya, Takao

2007-06-01

The electronics fields face serious problems associated with electric power; these include the development of ecologically friendly power-generation systems and ultralow-power-consuming circuits. Moreover, there is a demand for developing new power-transmission methods in the imminent era of ambient electronics, in which a multitude of electronic devices such as sensor networks will be used in our daily life to enhance security, safety and convenience. We constructed a sheet-type wireless power-transmission system by using state-of-the-art printing technologies using advanced electronic functional inks. This became possible owing to recent progress in organic semiconductor technologies; the diversity of chemical syntheses and processes on organic materials has led to a new class of organic semiconductors, dielectric layers and metals with excellent electronic functionalities. The new system directly drives electronic devices by transmitting power of the order of tens of watts without connectors, thereby providing an easy-to-use and reliable power source. As all of the components are manufactured on plastic films, it is easy to place the wireless power-transmission sheet over desks, floors, walls and any other location imaginable.

Immunomagnetic separation for MEMS-based biosensor of waterborne pathogens detection

NASA Astrophysics Data System (ADS)

Guo, Jianjiang; Zhang, Rongbiao

2017-07-01

Rapid isolation and detection of special pathogens present in environmental drinking water is critical for water quality monitoring. Numerical analysis and experimental investigations on immunomagnetic capture and isolation of waterborne pathogens with magnetic nanoparticles (MNPs) in microfluidic channel are performed. A finite-element COMSOL-based model is established to demonstrate the novel method of on-chip capturing pathogens using MNPs together with periodic pulse magnetic field. Simulation results determine the optimum magnetic pole current and switching frequency for magnetic separation. With the magnetic isolation experiment platform built up, as a pathogen example of Escherichia coli O157:H7, the performance of the method is experimentally verified. Both numerical and experimental results are found to agree reasonably well. Results of these investigations show that the capture efficiency of the immunomagnetic separation method is more than 92%, which could be encouraging for the design and optimization of MEMS-based biosensor of waterborne pathogen detection.

Fabricating micro-instruments in surface-micromachined polycrystalline silicon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Comtois, J.H.; Michalicek, M.A.; Barron, C.C.

1997-04-01

Smaller, lighter instruments can be fabricated as Micro-Electro-Mechanical Systems (MEMS), having micron scale moving parts packaged together with associated control and measurement electronics. Batch fabrication of these devices will make economical applications such as condition-based machine maintenance and remote sensing. The choice of instrumentation is limited only by the designer`s imagination. This paper presents one genre of MEMS fabrication, surface-micromachined polycrystalline silicon (polysilicon). Two currently available but slightly different polysilicon processes are presented. One is the ARPA-sponsored ``Multi-User MEMS ProcesS`` (MUMPS), available commercially through MCNC; the other is the Sandia National Laboratories ``Sandia Ultra-planar Multilevel MEMS Technology`` (SUMMiT). Example componentsmore » created in both processes will be presented, with an emphasis on actuators, actuator force testing instruments, and incorporating actuators into larger instruments.« less

Design, fabrication, and packaging of an integrated, wirelessly-powered optrode array for optogenetics application

PubMed Central

Kwon, Ki Yong; Lee, Hyung-Min; Ghovanloo, Maysam; Weber, Arthur; Li, Wen

2015-01-01

The recent development of optogenetics has created an increased demand for advancing engineering tools for optical modulation of neural circuitry. This paper details the design, fabrication, integration, and packaging procedures of a wirelessly-powered, light emitting diode (LED) coupled optrode neural interface for optogenetic studies. The LED-coupled optrode array employs microscale LED (μLED) chips and polymer-based microwaveguides to deliver light into multi-level cortical networks, coupled with microelectrodes to record spontaneous changes in neural activity. An integrated, implantable, switched-capacitor based stimulator (SCS) system provides high instantaneous power to the μLEDs through an inductive link to emit sufficient light and evoke neural activities. The presented system is mechanically flexible, biocompatible, miniaturized, and lightweight, suitable for chronic implantation in small freely behaving animals. The design of this system is scalable and its manufacturing is cost effective through batch fabrication using microelectromechanical systems (MEMS) technology. It can be adopted by other groups and customized for specific needs of individual experiments. PMID:25999823

Titanium dioxide thin films deposited by pulsed laser deposition and integration in radio frequency devices: Study of structure, optical and dielectric properties

NASA Astrophysics Data System (ADS)

Orlianges, Jean-Christophe; Crunteanu, Aurelian; Pothier, Arnaud; Merle-Mejean, Therese; Blondy, Pierre; Champeaux, Corinne

2012-12-01

Titanium dioxide presents a wide range of technological application possibilities due to its dielectric, electrochemical, photocatalytic and optical properties. The three TiO2 allotropic forms: anatase, rutile and brookite are also interesting, since they exhibit different properties, stabilities and growth modes. For instance, rutile has a high dielectric permittivity, of particular interest for the integration as dielectric in components such as microelectromechanical systems (MEMS) for radio frequency (RF) devices. In this study, titanium dioxide thin films are deposited by pulsed laser deposition. Characterizations by Raman spectroscopy and X-ray diffraction show the evolution of the structural properties. Thin films optical properties are investigated using spectroscopic ellipsometry and transmission measurements from UV to IR range. Co-planar waveguide (CPW) devices are fabricated based on these films. Their performances are measured in the RF domain and compared to simulation, leading to relative permittivity values in the range 30-120, showing the potentialities of the deposited material for capacitive switches applications.

Deformable Mirrors Correct Optical Distortions

NASA Technical Reports Server (NTRS)

2010-01-01

By combining the high sensitivity of space telescopes with revolutionary imaging technologies consisting primarily of adaptive optics, the Terrestrial Planet Finder is slated to have imaging power 100 times greater than the Hubble Space Telescope. To this end, Boston Micromachines Corporation, of Cambridge, Massachusetts, received Small Business Innovation Research (SBIR) contracts from the Jet Propulsion Laboratory for space-based adaptive optical technology. The work resulted in a microelectromechanical systems (MEMS) deformable mirror (DM) called the Kilo-DM. The company now offers a full line of MEMS DMs, which are being used in observatories across the world, in laser communication, and microscopy.

MEMS (Micro-Electro-Mechanical Systems) for Automotive and Consumer Electronics

NASA Astrophysics Data System (ADS)

Marek, Jiri; Gómez, Udo-Martin

MEMS sensors gained over the last two decades an impressive width of applications: (a) ESP: A car is skidding and stabilizes itself without driver intervention (b) Free-fall detection: A laptop falls to the floor and protects the hard drive by parking the read/write drive head automatically before impact. (c) Airbag: An airbag fires before the driver/occupant involved in an impending automotive crash impacts the steering wheel, thereby significantly reducing physical injury risk. MEMS sensors are sensing the environmental conditions and are giving input to electronic control systems. These crucial MEMS sensors are making system reactions to human needs more intelligent, precise, and at much faster reaction rates than humanly possible. Important prerequisites for the success of sensors are their size, functionality, power consumption, and costs. This technical progress in sensor development is realized by micro-machining. The development of these processes was the breakthrough to industrial mass-production for micro-electro-mechanical systems (MEMS). Besides leading-edge micromechanical processes, innovative and robust ASIC designs, thorough simulations of the electrical and mechanical behaviour, a deep understanding of the interactions (mainly over temperature and lifetime) of the package and the mechanical structures are needed. This was achieved over the last 20 years by intense and successful development activities combined with the experience of volume production of billions of sensors. This chapter gives an overview of current MEMS technology, its applications and the market share. The MEMS processes are described, and the challenges of MEMS, compared to standard IC fabrication, are discussed. The evolution of MEMS requirements is presented, and a short survey of MEMS applications is shown. Concepts of newest inertial sensors for ESP-systems are given with an emphasis on the design concepts of the sensing element and the evaluation circuit for achieving excellent noise performance. The chapter concludes with an outlook on arising new MEMS applications such as energy harvester and micro fuel cells.

Flexible Chip Scale Package and Interconnect for Implantable MEMS Movable Microelectrodes for the Brain.

PubMed

Jackson, Nathan; Muthuswamy, Jit

2009-04-01

We report here a novel approach called MEMS microflex interconnect (MMFI) technology for packaging a new generation of Bio-MEMS devices that involve movable microelectrodes implanted in brain tissue. MMFI addresses the need for (i) operating space for movable parts and (ii) flexible interconnects for mechanical isolation. We fabricated a thin polyimide substrate with embedded bond-pads, vias, and conducting traces for the interconnect with a backside dry etch, so that the flexible substrate can act as a thin-film cap for the MEMS package. A double gold stud bump rivet bonding mechanism was used to form electrical connections to the chip and also to provide a spacing of approximately 15-20 µm for the movable parts. The MMFI approach achieved a chip scale package (CSP) that is lightweight, biocompatible, having flexible interconnects, without an underfill. Reliability tests demonstrated minimal increases of 0.35 mΩ, 0.23 mΩ and 0.15 mΩ in mean contact resistances under high humidity, thermal cycling, and thermal shock conditions respectively. High temperature tests resulted in an increase in resistance of > 90 mΩ when aluminum bond pads were used, but an increase of ~ 4.2 mΩ with gold bond pads. The mean-time-to-failure (MTTF) was estimated to be at least one year under physiological conditions. We conclude that MMFI technology is a feasible and reliable approach for packaging and interconnecting Bio-MEMS devices.

A square wave is the most efficient and reliable waveform for resonant actuation of micro switches

NASA Astrophysics Data System (ADS)

Ben Sassi, S.; Khater, M. E.; Najar, F.; Abdel-Rahman, E. M.

2018-05-01

This paper investigates efficient actuation methods of shunt MEMS switches and other parallel-plate actuators. We start by formulating a multi-physics model of the micro switch, coupling the nonlinear Euler-Bernoulli beam theory with the nonlinear Reynolds equation to describe the structural and fluidic domains, respectively. The model takes into account fringing field effects as well as mid-plane stretching and squeeze film damping nonlinearities. Static analysis is undertaken using the differential quadrature method (DQM) to obtain the pull-in voltage, which is verified by means of the finite element model and validated experimentally. We develop a reduced order model employing the Galerkin method for the structural domain and DQM for the fluidic domain. The proposed waveforms are intended to be more suitable for integrated circuit standards. The dynamic response of the micro switch to harmonic, square and triangular waveforms are evaluated and compared experimentally and analytically. Low voltage actuation is obtained using dynamic pull-in with the proposed waveforms. In addition, global stability analysis carried out for the three signals shows advantages of employing the square signal as the actuation method in enhancing the performance of the micro switch in terms of actuation voltage, switching time, and sensitivity to initial conditions.

Improved Design of Optical MEMS Using the SUMMiT Fabrication Process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Michalicek, M.A.; Comtois, J.H.; Barron, C.C.

This paper describes the design and fabrication of optical Microelectromechanical Systems (MEMS) devices using the Sandia Ultra planar Multilevel MEMS Technology (SUMMiT) fabrication process. This state of the art process, offered by Sandia National Laboratories, provides unique and very advantageous features which make it ideal for optical devices. This enabling process permits the development of micromirror devices with near ideal characteristics which have previously been unrealizable in standard polysilicon processes. This paper describes such characteristics as elevated address electrodes, individual address wiring beneath the device, planarized mirror surfaces, unique post-process metallization, and the best active surface area to date.

A low-noise MEMS accelerometer for unattended ground sensor applications

NASA Astrophysics Data System (ADS)

Speller, Kevin E.; Yu, Duli

2004-09-01

A low-noise micro-machined servo accelerometer has been developed for use in Unattended Ground Sensors (UGS). Compared to conventional coil-and-magnet based velocity transducers, this Micro-Electro-Mechanical System (MEMS) accelerometer offers several key benefits for battlefield monitoring. Many UGS require a compass to determine deployment orientation with respect to magnetic North. This orientation information is critical for determining the bearing of incoming signals. Conventional sensors with sensing technology based on a permanent magnet can cause interference with a compass when used in close proximity. This problem is solved with a MEMS accelerometer which does not require any magnetic materials. Frequency information below 10 Hz is valuable for identification of signal sources. Conventional seismometers used in UGS are typically limited in frequency response from 20 to 200 Hz. The MEMS accelerometer has a flat frequency response from DC to 5 kHz. The wider spectrum of signals received improves detection, classification and monitoring on the battlefield. The DC-coupled output of the MEMS accelerometer also has the added benefit of providing tilt orientation data for the deployed UGS. Other performance parameters of the MEMS accelerometer that are important to UGS such as size, weight, shock survivability, phase response, distortion, and cross-axis rejection will be discussed. Additionally, field test data from human footsteps recorded with the MEMS accelerometer will be presented.

MEMS Integrated Submount Alignment for Optoelectronics

NASA Astrophysics Data System (ADS)

Shakespeare, W. Jeffrey; Pearson, Raymond A.; Grenestedt, Joachim L.; Hutapea, Parsaoran; Gupta, Vikas

2005-02-01

One of the most expensive and time-consuming production processes for single-mode fiber-optic components is the alignment of the photonic chip or waveguide to the fiber. The alignment equipment is capital intensive and usually requires trained technicians to achieve desired results. Current technology requires active alignment since tolerances are only ~0.2 μ m or less for a typical laser diode. This is accomplished using piezoelectric actuated stages and active optical feedback. Joining technologies such as soldering, epoxy bonding, or laser welding may contribute significant postbond shift, and final coupling efficiencies are often less than 80%. This paper presents a method of adaptive optical alignment to freeze in place directly on an optical submount using a microelectromechanical system (MEMS) shape memory alloy (SMA) actuation technology. Postbond shift is eliminated since the phase change is the alignment actuation. This technology is not limited to optical alignment but can be applied to a variety of MEMS actuations, including nano-actuation and nano-alignment for biomedical applications. Experimental proof-of-concept results are discussed, and a simple analytical model is proposed to predict the stress strain behavior of the optical submount. Optical coupling efficiencies and alignment times are compared with traditional processes. The feasibility of this technique in high-volume production is discussed.

A Dual-Linear Kalman Filter for Real-Time Orientation Determination System Using Low-Cost MEMS Sensors.

PubMed

Zhang, Shengzhi; Yu, Shuai; Liu, Chaojun; Yuan, Xuebing; Liu, Sheng

2016-02-20

To provide a long-time reliable orientation, sensor fusion technologies are widely used to integrate available inertial sensors for the low-cost orientation estimation. In this paper, a novel dual-linear Kalman filter was designed for a multi-sensor system integrating MEMS gyros, an accelerometer, and a magnetometer. The proposed filter precludes the impacts of magnetic disturbances on the pitch and roll which the heading is subjected to. The filter can achieve robust orientation estimation for different statistical models of the sensors. The root mean square errors (RMSE) of the estimated attitude angles are reduced by 30.6% under magnetic disturbances. Owing to the reduction of system complexity achieved by smaller matrix operations, the mean total time consumption is reduced by 23.8%. Meanwhile, the separated filter offers greater flexibility for the system configuration, as it is possible to switch on or off the second stage filter to include or exclude the magnetometer compensation for the heading. Online experiments were performed on the homemade miniature orientation determination system (MODS) with the turntable. The average RMSE of estimated orientation are less than 0.4° and 1° during the static and low-dynamic tests, respectively. More realistic tests on two-wheel self-balancing vehicle driving and indoor pedestrian walking were carried out to evaluate the performance of the designed MODS when high accelerations and angular rates were introduced. Test results demonstrate that the MODS is applicable for the orientation estimation under various dynamic conditions. This paper provides a feasible alternative for low-cost orientation determination.

A Dual-Linear Kalman Filter for Real-Time Orientation Determination System Using Low-Cost MEMS Sensors

PubMed Central

Zhang, Shengzhi; Yu, Shuai; Liu, Chaojun; Yuan, Xuebing; Liu, Sheng

2016-01-01

To provide a long-time reliable orientation, sensor fusion technologies are widely used to integrate available inertial sensors for the low-cost orientation estimation. In this paper, a novel dual-linear Kalman filter was designed for a multi-sensor system integrating MEMS gyros, an accelerometer, and a magnetometer. The proposed filter precludes the impacts of magnetic disturbances on the pitch and roll which the heading is subjected to. The filter can achieve robust orientation estimation for different statistical models of the sensors. The root mean square errors (RMSE) of the estimated attitude angles are reduced by 30.6% under magnetic disturbances. Owing to the reduction of system complexity achieved by smaller matrix operations, the mean total time consumption is reduced by 23.8%. Meanwhile, the separated filter offers greater flexibility for the system configuration, as it is possible to switch on or off the second stage filter to include or exclude the magnetometer compensation for the heading. Online experiments were performed on the homemade miniature orientation determination system (MODS) with the turntable. The average RMSE of estimated orientation are less than 0.4° and 1° during the static and low-dynamic tests, respectively. More realistic tests on two-wheel self-balancing vehicle driving and indoor pedestrian walking were carried out to evaluate the performance of the designed MODS when high accelerations and angular rates were introduced. Test results demonstrate that the MODS is applicable for the orientation estimation under various dynamic conditions. This paper provides a feasible alternative for low-cost orientation determination. PMID:26907294

Evaluation of a Programmable Voltage-Controlled MEMS Oscillator, Type SiT3701, Over a Wide Temperature Range

NASA Technical Reports Server (NTRS)

Patterson, Richard; Hammoud, Ahmad

2009-01-01

Semiconductor chips based on MEMS (Micro-Electro-Mechanical Systems) technology, such as sensors, transducers, and actuators, are becoming widely used in today s electronics due to their high performance, low power consumption, tolerance to shock and vibration, and immunity to electro-static discharge. In addition, the MEMS fabrication process allows for the miniaturization of individual chips as well as the integration of various electronic circuits into one module, such as system-on-a-chip. These measures would simplify overall system design, reduce parts count and interface, improve reliability, and reduce cost; and they would meet requirements of systems destined for use in space exploration missions. In this work, the performance of a recently-developed MEMS voltage-controlled oscillator was evaluated under a wide temperature range. Operation of this new commercial-off-the-shelf (COTS) device was also assessed under thermal cycling to address some operational conditions of the space environment

New Research on MEMS Acoustic Vector Sensors Used in Pipeline Ground Markers

PubMed Central

Song, Xiaopeng; Jian, Zeming; Zhang, Guojun; Liu, Mengran; Guo, Nan; Zhang, Wendong

2015-01-01

According to the demands of current pipeline detection systems, the above-ground marker (AGM) system based on sound detection principle has been a major development trend in pipeline technology. A novel MEMS acoustic vector sensor for AGM systems which has advantages of high sensitivity, high signal-to-noise ratio (SNR), and good low frequency performance has been put forward. Firstly, it is presented that the frequency of the detected sound signal is concentrated in a lower frequency range, and the sound attenuation is relatively low in soil. Secondly, the MEMS acoustic vector sensor structure and basic principles are introduced. Finally, experimental tests are conducted and the results show that in the range of 0°∼90°, when r = 5 m, the proposed MEMS acoustic vector sensor can effectively detect sound signals in soil. The measurement errors of all angles are less than 5°. PMID:25609046

Study of the Use of Time-Mean Vortices to Generate Lift for MAV Applications

DTIC Science & Technology

2011-05-31

microplate to in-plane resonance. Computational effort centers around optimization of a range of parameters (geometry, frequency, amplitude of oscillation, etc...issue involved. Towards this end, a suspended microplate was fabricated via MEMS technology and driven to in-plane resonance via Lorentz force...force to drive the suspended MEMS-based microplate to in-plane resonance. Computational effort centers around optimization of a range of parameters

Proceedings of the International Conference on Integrated Micro/Nanotechnology for Space Applications

NASA Technical Reports Server (NTRS)

1995-01-01

The recent evolution of microelectronic technologies coupled with the growth of micro-electro-mechanical systems (MEMS) has had significant impact in the commercial sector. The focus of this conference was to anticipate and extend the incorporation of nano-electronics and MEMS into application specific integrated microinstruments (ASIM's) in space systems. Presentations ranged from mission application of nano-satellites to silicon micromachining for photonic applications.

Optimizing Pt/TiO2 templates for textured PZT growth and MEMS devices

NASA Astrophysics Data System (ADS)

Potrepka, Daniel; Fox, Glenn; Sanchez, Luz; Polcawich, Ronald

2013-03-01

Crystallographic texture of lead zirconate titanate (PZT) thin films strongly influences piezoelectric properties used in MEMS applications. Textured growth can be achieved by relying on crystal growth habit and can also be initiated by the use of a seed-layer heteroepitaxial template. Template choice and the process used to form it determine structural quality, ultimately influencing performance and reliability of MEMS PZT devices such as switches, filters, and actuators. This study focuses on how 111-textured PZT is generated by a combination of crystal habit and templating mechanisms that occur in the PZT/bottom-electrode stack. The sequence begins with 0001-textured Ti deposited on thermally grown SiO2 on a Si wafer. The Ti is converted to 100-textured TiO2 (rutile) through thermal oxidation. Then 111-textured Pt can be grown to act as a template for 111-textured PZT. Ti and Pt are deposited by DC magnetron sputtering. TiO2 and Pt film textures and structure were optimized by variation of sputtering deposition times, temperatures and power levels, and post-deposition anneal conditions. The relationship between Ti, TiO2, and Pt texture and their impact on PZT growth will be presented. Also affiliated with U.S. Army Research Lab, Adelphi, MD 20783, USA

A MEMS torsion magnetic sensor with reflective blazed grating integration

NASA Astrophysics Data System (ADS)

Long, Liang; Zhong, Shaolong

2016-07-01

A novel magnetic sensor based on a permanent magnet and blazed grating is presented in this paper. The magnetic field is detected by measuring the diffracted wavelength of the blazed grating which is changed by the torsion motion of a torsion sensitive micro-electromechanical system (MEMS) structure with a permanent magnet attached. A V-shape grating structure is obtained by wet etching on a (1 0 0) SOI substrate. When the magnet is magnetized in different directions, the in-plane or out-of-plane magnetic field is detected by a sensor. The MEMS magnetic sensor with a permanent magnet is fabricated after analytical design and bulk micromachining processes. The magnetic-sensing capability of the sensor is tested by fiber-optic detection system. The result shows the sensitivities of the in-plane and out-of-plane magnetic fields are 3.6 pm μT-1 and 5.7 pm μT-1, respectively. Due to utilization of the permanent magnet and fiber-optic detection, the sensor shows excellent capability of covering the high-resolution detection of low-frequency signals. In addition, the sensitive direction of the magnetic sensor can be easily switched by varying the magnetized direction of the permanent magnet, which offers a simple way to achieve tri-axis magnetic sensor application.

A low-cost CMOS-MEMS piezoresistive accelerometer with large proof mass.

PubMed

Khir, Mohd Haris Md; Qu, Peng; Qu, Hongwei

2011-01-01

This paper reports a low-cost, high-sensitivity CMOS-MEMS piezoresistive accelerometer with large proof mass. In the device fabricated using ON Semiconductor 0.5 μm CMOS technology, an inherent CMOS polysilicon thin film is utilized as the piezoresistive sensing material. A full Wheatstone bridge was constructed through easy wiring allowed by the three metal layers in the 0.5 μm CMOS technology. The device fabrication process consisted of a standard CMOS process for sensor configuration, and a deep reactive ion etching (DRIE) based post-CMOS microfabrication for MEMS structure release. A bulk single-crystal silicon (SCS) substrate is included in the proof mass to increase sensor sensitivity. In device design and analysis, the self heating of the polysilicon piezoresistors and its effect to the sensor performance is also discussed. With a low operating power of 1.5 mW, the accelerometer demonstrates a sensitivity of 0.077 mV/g prior to any amplification. Dynamic tests have been conducted with a high-end commercial calibrating accelerometer as reference.

Two-dimensional (2D) displacement measurement of moving objects using a new MEMS binocular vision system

NASA Astrophysics Data System (ADS)

Di, Si; Lin, Hui; Du, Ruxu

2011-05-01

Displacement measurement of moving objects is one of the most important issues in the field of computer vision. This paper introduces a new binocular vision system (BVS) based on micro-electro-mechanical system (MEMS) technology. The eyes of the system are two microlenses fabricated on a substrate by MEMS technology. The imaging results of two microlenses are collected by one complementary metal-oxide-semiconductor (CMOS) array. An algorithm is developed for computing the displacement. Experimental results show that as long as the object is moving in two-dimensional (2D) space, the system can effectively estimate the 2D displacement without camera calibration. It is also shown that the average error of the displacement measurement is about 3.5% at different object distances ranging from 10 cm to 35 cm. Because of its low cost, small size and simple setting, this new method is particularly suitable for 2D displacement measurement applications such as vision-based electronics assembly and biomedical cell culture.

MEMS-based liquid lens for capsule endoscope

NASA Astrophysics Data System (ADS)

Seo, S. W.; Han, S.; Seo, J. H.; Kim, Y. M.; Kang, M. S.; Min, N. G.; Choi, W. B.; Sung, M. Y.

2008-03-01

The capsule endoscope, a new application area of digital imaging, is growing rapidly but needs the versatile imaging capabilities such as auto-focusing and zoom-in to be an active diagnostic tool. The liquid lens based on MEMS technology can be a strong candidate because it is able to be small enough. In this paper, a cylinder-type liquid lens was designed based on Young-Lippmann model and then fabricated with MEMS technology combining the silicon thin-film process and the wafer bonding process. The focal length of the lens module including the fabricated liquid lens was changed reproducibly as a function of the applied voltage. With the change of 30V in the applied bias, the focal length of the constructed lens module could be tuned in the range of about 42cm. The fabricated liquid lens was also proven to be small enough to be adopted in the capsule endoscope, which means the liquid lens can be utilized for the imaging capability improvement of the capsule endoscope.

Development of a high hertz-stress contact for conventional batch production using a unique scribing technology

NASA Astrophysics Data System (ADS)

Bhuiyan, M. M. I.; Alamgir, T.; Bhuiyan, M.; Kajihara, M.

2013-12-01

Gradually the electronic devices are getting more compact dimension with respect to the width and thickness. As a result, the contacts are becoming thinner and which leads the contact to be loose and unstable contact. In comercial stamping methode, connector tip diameter should be more than 300μm due to its size limitation. Consequently, the connector contact resistance is becoming higher due to weak contact force. To overcome this problem there were few more basic research using MEMS and Electro Fine Forming (EFF) technology to make high Hertz-Stress Contact (5μm) due to the limitation in the commercial stamping process and the result was in satisfactory level. However, since the MEMS and EFF fabrication is costly therefore, a new method is introduced in this paper using the commercial Phosphor Bronze stamping method to reduce the production cost. Moreover, scribing method is used to make tip on the contact. Accordingly, more compact fine pitch contact is successfully fabricated and tested with 5μm High Hertz Stress without using the MEMS and EFF technology. Hence the manufactured contact resistance becomes less than 20mΩ ±5mΩ.

Biomimetic MEMS to assist, enhance, and expand human sensory perceptions: a survey on state-of-the-art developments

NASA Astrophysics Data System (ADS)

Makarczuk, Teresa; Matin, Tina R.; Karman, Salmah B.; Diah, S. Zaleha M.; Davaji, Benyamin; Macqueen, Mark O.; Mueller, Jeanette; Schmid, Ulrich; Gebeshuber, Ille C.

2011-06-01

The human senses are of extraordinary value but we cannot change them even if this proves to be a disadvantage in modern times. However, we can assist, enhance and expand these senses via MEMS. Current MEMS cover the range of the human sensory system, and additionally provide data about signals that are too weak for the human sensory system (in terms of signal strength) and signal types that are not covered by the human sensory system. Biomimetics deals with knowledge transfer from biology to technology. In our interdisciplinary approach existing MEMS sensor designs shall be modified and adapted (to keep costs at bay), via biomimetic knowledge transfer of outstanding sensory perception in 'best practice' organisms (e.g. thermoreception, UV sensing, electromagnetic sense). The MEMS shall then be linked to the human body (mainly ex corpore to avoid ethics conflicts), to assist, enhance and expand human sensory perception. This paper gives an overview of senses in humans and animals, respective MEMS sensors that are already on the market and gives a list of possible applications of such devices including sensors that vibrate when a blind person approaches a kerb stone edge and devices that allow divers better orientation under water (echolocation, ultrasound).

Ball driven type MEMS SAD for artillery fuse

NASA Astrophysics Data System (ADS)

Seok, Jin Oh; Jeong, Ji-hun; Eom, Junseong; Lee, Seung S.; Lee, Chun Jae; Ryu, Sung Moon; Oh, Jong Soo

2017-01-01

The SAD (safety and arming device) is an indispensable fuse component that ensures safe and reliable performance during the use of ammunition. Because the application of electronic devices for smart munitions is increasing, miniaturization of the SAD has become one of the key issues for next-generation artillery fuses. Based on MEMS technology, various types of miniaturized SADs have been proposed and fabricated. However, none of them have been reported to have been used in actual munitions due to their lack of high impact endurance and complicated explosive train arrangements. In this research, a new MEMS SAD using a ball driven mechanism, is successfully demonstrated based on a UV LIGA (lithography, electroplating and molding) process. Unlike other MEMS SADs, both high impact endurance and simple structure were achieved by using a ball driven mechanism. The simple structural design also simplified the fabrication process and increased the processing yield. The ball driven type MEMS SAD performed successfully under the desired safe and arming conditions of a spin test and showed fine agreement with the FEM simulation result, conducted prior to its fabrication. A field test was also performed with a grenade launcher to evaluate the SAD performance in the firing environment. All 30 of the grenade samples equipped with the proposed MEMS SAD operated successfully under the high-G setback condition.

Impact of radiations on the electromechanical properties of materials and on the piezoresistive and capacitive transduction mechanisms used in microsystems

NASA Astrophysics Data System (ADS)

Francis, Laurent A.; Gkotsis, Petros; Kilchytska, Valeriya; Tang, Xiaohui; Druart, Sylvain; Raskin, Jean-Pierre; Flandre, Denis

2013-03-01

The impact of different types of radiation on the electromechanical properties of materials used in microfabrication and on the capacitive and piezoresistive transduction mechanisms of MEMS is investigated. MEMS technologies could revolutionize avionics, satellite and space applications provided that the stress conditions which can compromise the reliability of microsystems in these environments are well understood. Initial tests with MEMS revealed a vulnerability of some types of devices to radiation induced dielectric charging, a physical mechanism which also affects microelectronics, however integration of novel functional materials in microfabrication and the current trend to substitute SiO2 with high-k dielectrics in ICs pose new questions regarding reliability in radiation environments. The performance of MEMS devices with moving parts could also degrade due to radiation induced changes in the mechanical properties of the materials. It is thus necessary to investigate the effects of radiation on the properties of thin films used in microfabrication and here we report on tests with γ, high energy protons and fast neutrons radiation. Prototype SOI based MEMS magnetometers which were developed in UCL are also used as test vehicles to investigate radiation effects on the reliability of magnetically actuated and capacitively coupled MEMS.

Internet MEMS design tools based on component technology

NASA Astrophysics Data System (ADS)

Brueck, Rainer; Schumer, Christian

1999-03-01

The micro electromechanical systems (MEMS) industry in Europe is characterized by small and medium sized enterprises specialized on products to solve problems in specific domains like medicine, automotive sensor technology, etc. In this field of business the technology driven design approach known from micro electronics is not appropriate. Instead each design problem aims at its own, specific technology to be used for the solution. The variety of technologies at hand, like Si-surface, Si-bulk, LIGA, laser, precision engineering requires a huge set of different design tools to be available. No single SME can afford to hold licenses for all these tools. This calls for a new and flexible way of designing, implementing and distributing design software. The Internet provides a flexible manner of offering software access along with methodologies of flexible licensing e.g. on a pay-per-use basis. New communication technologies like ADSL, TV cable of satellites as carriers promise to offer a bandwidth sufficient even for interactive tools with graphical interfaces in the near future. INTERLIDO is an experimental tool suite for process specification and layout verification for lithography based MEMS technologies to be accessed via the Internet. The first version provides a Java implementation even including a graphical editor for process specification. Currently, a new version is brought into operation that is based on JavaBeans component technology. JavaBeans offers the possibility to realize independent interactive design assistants, like a design rule checking assistants, a process consistency checking assistants, a technology definition assistants, a graphical editor assistants, etc. that may reside distributed over the Internet, communicating via Internet protocols. Each potential user thus is able to configure his own dedicated version of a design tool set dedicated to the requirements of the current problem to be solved.

NASA NDE Applications for Mobile MEMS Devices and Sensors

NASA Technical Reports Server (NTRS)

Wilson, William C.; Atkinson, Gary M.; Barclay, R. O.

2008-01-01

NASA would like new devices and sensors for performing nondestructive evaluation (NDE) of aerospace vehicles. These devices must be small in size/volume, mass, and power consumption. The devices must be autonomous and mobile so they can access the internal structures of aircraft and spacecraft and adequately monitor the structural health of these craft. The platforms must be mobile in order to transport NDE sensors for evaluating structural integrity and determining whether further investigations will be required. Microelectromechanical systems (MEMS) technology is crucial to the development of the mobile platforms and sensor systems. This paper presents NASA s needs for micro mobile platforms and MEMS sensors that will enable NDE to be performed on aerospace vehicles.

An approach to optimal semi-active control of vibration energy harvesting based on MEMS

NASA Astrophysics Data System (ADS)

Rojas, Rafael A.; Carcaterra, Antonio

2018-07-01

In this paper the energy harvesting problem involving typical MEMS technology is reduced to an optimal control problem, where the objective function is the absorption of the maximum amount of energy in a given time interval from a vibrating environment. The interest here is to identify a physical upper bound for this energy storage. The mathematical tool is a new optimal control called Krotov's method, that has not yet been applied to engineering problems, except in quantum dynamics. This approach leads to identify new maximum bounds to the energy harvesting performance. Novel MEMS-based device control configurations for vibration energy harvesting are proposed with particular emphasis to piezoelectric, electromagnetic and capacitive circuits.

A Hazardous Gas Detection System for Aerospace and Commercial Applications

NASA Technical Reports Server (NTRS)

Hunter, G. W.; Neudeck, P. G.; Chen, L. - Y.; Makel, D. B.; Liu, C. C.; Wu, Q. H.; Knight, D.

1998-01-01

The detection of explosive conditions in aerospace propulsion applications is important for safety and economic reasons. Microfabricated hydrogen, oxygen, and hydrocarbon sensors as well as the accompanying hardware and software are being developed for a range of aerospace safety applications. The development of these sensors is being done using MEMS (Micro ElectroMechanical Systems) based technology and SiC-based semiconductor technology. The hardware and software allows control and interrogation of each sensor head and reduces accompanying cabling through multiplexing. These systems are being applied on the X-33 and on an upcoming STS-95 Shuttle mission. A number of commercial applications are also being pursued. It is concluded that this MEMS-based technology has significant potential to reduce costs and increase safety in a variety of aerospace applications.

A Hazardous Gas Detection System for Aerospace and Commercial Applications

NASA Technical Reports Server (NTRS)

Hunter, G. W.; Neudeck, P. G.; Chen, L.-Y.; Makel, D. B.; Liu, C. C.; Wu, Q. H.; Knight, D.

1998-01-01

The detection of explosive conditions in aerospace propulsion applications is important for safety and economic reasons. Microfabricated hydrogen, oxygen, and hydrocarbon sensors as well as the accompanying hardware and software are being, developed for a range of aerospace safety applications. The development of these sensors is being done using MEMS (Micro ElectroMechanical Systems) based technology and SiC-based semiconductor technology. The hardware and software allows control and interrocation of each sensor head and reduces accompanying cabling through multiplexing. These systems are being, applied on the X-33 and on an upcoming STS-95 Shuttle mission. A number of commercial applications are also being pursued. It is concluded that this MEMS-based technology has significant potential to reduce costs and increase safety in a variety of aerospace applications.

Concept for a Micro Autonomous Ultrasonic Instrument (MAUI)

NASA Technical Reports Server (NTRS)

Wilson, William C.; Atkinson, Gary M.

2002-01-01

We investigate a concept for the construction a mobile Micro Optical ElectroMechanical Systems (MOEMS) based laser ultrasonic instrument to serve as a Micro Autonomous Ultrasonic Instrument (MAUI). The system will consist of a laser ultrasonic instrument fabricated using Micro Electro-Mechanical Systems (MEMS) technology, and a MEMS based walking platform like those developed by Pister et al. at Berkeley. This small system will allow for automated remote Non-Destructive Evaluation (NDE) of aerospace vehicles.

Programmable differential capacitance-to-voltage converter for MEMS accelerometers

NASA Astrophysics Data System (ADS)

Royo, G.; Sánchez-Azqueta, C.; Gimeno, C.; Aldea, C.; Celma, S.

2017-05-01

Capacitive MEMS sensors exhibit an excellent noise performance, high sensitivity and low power consumption. They offer a huge range of applications, being the accelerometer one of its main uses. In this work, we present the design of a capacitance-to-voltage converter in CMOS technology to measure the acceleration from the capacitance variations. It is based on a low-power, fully-differential transimpedance amplifier with low input impedance and a very low input noise.

Sandia Advanced MEMS Design Tools, Version 2.2.5

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yarberry, Victor; Allen, James; Lantz, Jeffery

2010-01-19

The Sandia National Laboratories Advanced MEMS Design Tools, Version 2.2.5, is a collection of menus, prototype drawings, and executables that provide significant productivity enhancements when using AutoCAD to design MEMS components. This release is designed for AutoCAD 2000i, 2002, or 2004 and is supported under Windows NT 4.0, Windows 2000, or XP. SUMMiT V (Sandia Ultra planar Multi level MEMS Technology) is a 5 level surface micromachine fabrication technology, which customers internal and external to Sandia can access to fabricate prototype MEMS devices. This CD contains an integrated set of electronic files that: a) Describe the SUMMiT V fabrication processmore » b) Facilitate the process of designing MEMS with the SUMMiT process (prototype file, Design Rule Checker, Standard Parts Library) New features in this version: AutoCAD 2004 support has been added. SafeExplode ? a new feature that explodes blocks without affecting polylines (avoids exploding polylines into objects that are ignored by the DRC and Visualization tools). Layer control menu ? a pull-down menu for selecting layers to isolate, freeze, or thaw. Updated tools: A check has been added to catch invalid block names. DRC features: Added username/password validation, added a method to update the user?s password. SNL_DRC_WIDTH ? a value to control the width of the DRC error lines. SNL_BIAS_VALUE ? a value use to offset selected geometry SNL_PROCESS_NAME ? a value to specify the process name Documentation changes: The documentation has been updated to include the new features. While there exist some files on the CD that are used in conjunction with software package AutoCAD, these files are not intended for use independent of the CD. Note that the customer must purchase his/her own copy of AutoCAD to use with these files.« less

Microtechnology management considering test and cost aspects for stacked 3D ICs with MEMS

NASA Astrophysics Data System (ADS)

Hahn, K.; Wahl, M.; Busch, R.; Grünewald, A.; Brück, R.

2018-01-01

Innovative automotive systems require complex semiconductor devices currently only available in consumer grade quality. The European project TRACE will develop and demonstrate methods, processes, and tools to facilitate usage of Consumer Electronics (CE) components to be deployable more rapidly in the life-critical automotive domain. Consumer electronics increasingly use heterogeneous system integration methods and "More than Moore" technologies, which are capable to combine different circuit domains (Analog, Digital, RF, MEMS) and which are integrated within SiP or 3D stacks. Making these technologies or at least some of the process steps available under automotive electronics requirements is an important goal to keep pace with the growing demand for information processing within cars. The approach presented in this paper aims at a technology management and recommendation system that covers technology data, functional and non-functional constraints, and application scenarios, and that will comprehend test planning and cost consideration capabilities.

Uncertainty quantification analysis of the dynamics of an electrostatically actuated microelectromechanical switch model

NASA Astrophysics Data System (ADS)

Snow, Michael G.; Bajaj, Anil K.

2015-08-01

This work presents an uncertainty quantification (UQ) analysis of a comprehensive model for an electrostatically actuated microelectromechanical system (MEMS) switch. The goal is to elucidate the effects of parameter variations on certain key performance characteristics of the switch. A sufficiently detailed model of the electrostatically actuated switch in the basic configuration of a clamped-clamped beam is developed. This multi-physics model accounts for various physical effects, including the electrostatic fringing field, finite length of electrodes, squeeze film damping, and contact between the beam and the dielectric layer. The performance characteristics of immediate interest are the static and dynamic pull-in voltages for the switch. Numerical approaches for evaluating these characteristics are developed and described. Using Latin Hypercube Sampling and other sampling methods, the model is evaluated to find these performance characteristics when variability in the model's geometric and physical parameters is specified. Response surfaces of these results are constructed via a Multivariate Adaptive Regression Splines (MARS) technique. Using a Direct Simulation Monte Carlo (DSMC) technique on these response surfaces gives smooth probability density functions (PDFs) of the outputs characteristics when input probability characteristics are specified. The relative variation in the two pull-in voltages due to each of the input parameters is used to determine the critical parameters.

Digital SPC switching technology: Foreign technology assessment

NASA Astrophysics Data System (ADS)

Fischman, Kurt; Jorstad, Norman D.

1990-12-01

This paper provides a foreign technology assessment of digital switching technology. Leading suppliers of digital switching technology are identified; although the United States holds a large part of the market, major companies in France, Sweden, Japan, the U.K., and Germany are also important. These countries, along with Belgium and Canada, are the most innovative and technically advanced. A listing is provided of transfers of digital switching technology to non-COCOM countries through licensing and joint ventures which reflects the widespread dissemination of this technology. Detailed technical specifications are provided for selected digital switching systems worldwide. The report concludes that considering the degree to which the technology is in place, that control of digital switching technology may not be feasible.

Poly-SiGe MEMS actuators for adaptive optics

NASA Astrophysics Data System (ADS)

Lin, Blake C.; King, Tsu-Jae; Muller, Richard S.

2006-01-01

Many adaptive optics (AO) applications require mirror arrays with hundreds to thousands of segments, necessitating a CMOS-compatible MEMS process to integrate the mirrors with their driving electronics. This paper proposes a MEMS actuator that is fabricated using low-temperature polycrystalline silicon-germanium (poly-SiGe) surface-micromaching technology (total thermal budget is 6 hours at or below 425°C). The MEMS actuator consists of three flexures and a hexagonal platform, on which a micromirror is to be assembled. The flexures are made of single-layer poly-SiGe with stress gradient across thickness of the film, making them bend out-of-plane after sacrificial-layer release to create a large nominal gap. The platform, on the other hand, has an additional stress-balancing SiGe layer deposited on top, making the dual-layer stack stay flat after release. Using this process, we have successfully fabricated the MEMS actuator which is lifted 14.6 μm out-of-plane by 290-μm-long flexures. The 2-μm-thick hexagonal mirror-platform exhibits a strain gradient of -5.5×10 -5 μm -1 (equivalent to 18 mm radius-of-curvature), which would be further reduced once the micromirror is assembled.

Producing fluid flow using 3D carbon electrodes

NASA Astrophysics Data System (ADS)

Rouabah, H. A.; Park, B. Y.; Zaouk, R. B.; Madou, M. J.; Green, Nicolas G.

2008-12-01

Moving and manipulating bio-particles and fluids on the microscale is central to many lab-on-a-chip applications. Techniques for pumping fluids which use electric fields have shown promise using both DC and AC voltages. AC techniques, however, require the use of integrated metal electrodes which have a low resistance but can suffer from unwanted chemical reactions even at low potentials. In this paper we introduce the use of carbon MEMS technology (C-MEMS), a fabrication method which produces 3D conductive polymeric structures. Results are presented of the fabrication of an innovative design of 3D AC-electroosmotic micropump and preliminary experimental measurements which demonstrate the potential of both the technology and the design.

A novel safety device with metal counter meshing gears discriminator directly driven by axial flux permanent magnet micromotors based on MEMS technology

NASA Astrophysics Data System (ADS)

Zhang, Weiping; Chen, Wenyuan; Zhao, Xiaolin; Li, Shengyong; Jiang, Yong

2005-08-01

In a novel safety device based on MEMS technology for high consequence systems, the discriminator consists of two groups of metal counter meshing gears and two pawl/ratchet wheel mechanisms. Each group of counter meshing gears is onepiece and driven directly by an axial flux permanent magnet micromotor respectively. The energy-coupling element is an optical shutter with two collimators and a coupler wheel. The safety device's probability is less than 1/106. It is fabricated by combination of an LiGA-like process and precision mechanical engineering. The device has simple structure, few dynamic problems, high strength and strong reliability.

Intensity modulation of a terahertz bandpass filter: utilizing image currents induced on MEMS reconfigurable metamaterials.

PubMed

Hu, Fangrong; Fan, Yixing; Zhang, Xiaowen; Jiang, Wenying; Chen, Yuanzhi; Li, Peng; Yin, Xianhua; Zhang, Wentao

2018-01-01

We experimentally demonstrated a tunable terahertz bandpass filter based on microelectromechanical systems (MEMS) reconfigurable metamaterials. The unit cell of the filter consists of two split-ring resonators (SRRs) and a movable bar. Initially, the movable bar situates at the center of the unit cell, and the filter has two passbands whose central frequencies locate at 0.65 and 0.96 THz. The intensity of the two passbands can be actively modulated by the movable bar, and a maximum modulation depth of 96% is achieved at 0.96 THz. The mechanism of tunability is investigated using the finite-integration time-domain method. The result shows that the image currents induced on the movable bar are opposite the resonance currents induced on the SRRs and, thus, weaken the oscillating intensity of the resonance currents. This scheme paves the way to dynamically control and switch the terahertz wave at some constant frequencies utilizing induced image currents.

Microelectromechanical (MEM) thermal actuator

DOEpatents

Garcia, Ernest J [Albuquerque, NM; Fulcher, Clay W. G. [Sandia Park, NM

2012-07-31

Microelectromechanical (MEM) buckling beam thermal actuators are disclosed wherein the buckling direction of a beam is constrained to a desired direction of actuation, which can be in-plane or out-of-plane with respect to a support substrate. The actuators comprise as-fabricated, linear beams of uniform cross section supported above the substrate by supports which rigidly attach a beam to the substrate. The beams can be heated by methods including the passage of an electrical current through them. The buckling direction of an initially straight beam upon heating and expansion is controlled by incorporating one or more directional constraints attached to the substrate and proximal to the mid-point of the beam. In the event that the beam initially buckles in an undesired direction, deformation of the beam induced by contact with a directional constraint generates an opposing force to re-direct the buckling beam into the desired direction. The displacement and force generated by the movement of the buckling beam can be harnessed to perform useful work, such as closing contacts in an electrical switch.

Faster sensitivity and non-antimonite permanent photoresist for MEMS

NASA Astrophysics Data System (ADS)

Misumi, Koichi; Saito, Koji; Yamanouchi, Atsushi; Senzaki, Takahiro; Okui, Toshiki; Honma, Hideo

2006-03-01

Micro Electro Mechanical Systems (MEMS) is a three-dimensional micro-fabrication technology based on photolithography. The fields of application are extensive and wide-ranging. Among the applications, those that have already acquired a large market include acceleration sensors for airbags of automobiles, pressure sensors for engine control, inkjet printer heads and thin film magnetic heads. The market is expected to further expand in the optic and biology-related fields in the future. In the MEMS field, the packaging accounts for the cost, and it is difficult to standardize due to the low production volume of highly specific technology application. A typical application in the MEMS process would be to conduct plating and etching (Deep RIE) through an intermediate layer of photoresist patterns, but there are cases where the photoresist itself is left therein as a permanent film. A photoresist composed of epoxy resin as the main component can form the permanent film through a catalyst of the optical cationic polymerizating initiator. In general, the optical cationic polymerizating initiator is of onium salt with antimonite as the anion group due to the nature of the hardening rate or the exposure energy. This paper presents the development status of a high sensitivity permanent photoresist made of epoxy resin as the main component with non-antimonite optical cationic polymerizating initiator with concerns to the impact to the environment and material for packaging.

MEMS capacitive accelerometer-based middle ear microphone.

PubMed

Young, Darrin J; Zurcher, Mark A; Semaan, Maroun; Megerian, Cliff A; Ko, Wen H

2012-12-01

The design, implementation, and characterization of a microelectromechanical systems (MEMS) capacitive accelerometer-based middle ear microphone are presented in this paper. The microphone is intended for middle ear hearing aids as well as future fully implantable cochlear prosthesis. Human temporal bones acoustic response characterization results are used to derive the accelerometer design requirements. The prototype accelerometer is fabricated in a commercial silicon-on-insulator (SOI) MEMS process. The sensor occupies a sensing area of 1 mm × 1 mm with a chip area of 2 mm × 2.4 mm and is interfaced with a custom-designed low-noise electronic IC chip over a flexible substrate. The packaged sensor unit occupies an area of 2.5 mm × 6.2 mm with a weight of 25 mg. The sensor unit attached to umbo can detect a sound pressure level (SPL) of 60 dB at 500 Hz, 35 dB at 2 kHz, and 57 dB at 8 kHz. An improved sound detection limit of 34-dB SPL at 150 Hz and 24-dB SPL at 500 Hz can be expected by employing start-of-the-art MEMS fabrication technology, which results in an articulation index of approximately 0.76. Further micro/nanofabrication technology advancement is needed to enhance the microphone sensitivity for improved understanding of normal conversational speech.

A Compact and Low-Cost MEMS Loudspeaker for Digital Hearing Aids.

PubMed

Sang-Soo Je; Rivas, F; Diaz, R E; Jiuk Kwon; Jeonghwan Kim; Bakkaloglu, B; Kiaei, S; Junseok Chae

2009-10-01

A microelectromechanical-systems (MEMS)-based electromagnetically actuated loudspeaker to reduce form factor, cost, and power consumption, and increase energy efficiency in hearing-aid applications is presented. The MEMS loudspeaker has multilayer copper coils, an NiFe soft magnet on a thin polyimide diaphragm, and an NdFeB permanent magnet on the perimeter. The coil impedance is measured at 1.5 Omega, and the resonant frequency of the diaphragm is located far from the audio frequency range. The device is driven by a power-scalable, 0.25-mum complementary metal-oxide semiconductor class-D SigmaDelta amplifier stage. The class-D amplifier is formed by a differential H-bridge driven by a single bit, pulse-density-modulated SigmaDelta bitstream at a 1.2-MHz clock rate. The fabricated MEMS loudspeaker generates more than 0.8-mum displacement, equivalent to 106-dB sound pressure level (SPL), with 0.13-mW power consumption. Driven by the SigmaDelta class-D amplifier, the MEMS loudspeaker achieves measured 65-dB total harmonic distortion (THD) with a measurement uncertainty of less than 10%. Energy-efficient and cost-effective advanced hearing aids would benefit from further miniaturization via MEMS technology. The results from this study appear very promising for developing a compact, mass-producible, low-power loudspeaker with sufficient sound generation for hearing-aid applications.

Reconfigurable Antennas for High Data Rate Multi-beam Communication Systems

NASA Technical Reports Server (NTRS)

Bernhard, Jennifer T.; Michielssen, Eric

2005-01-01

High-speed (2-100 Mb/sec) wireless data communication - whether land- or satellite-based - faces a major challenge: high error rates caused by interference and unpredictable environments. A planar antenna system that can be reconfigured to respond to changing conditions has the potential to dramatically improve data throughput and system reliability. Moreover, new planar antenna designs that reduce array size, weight, and cost can have a significant impact on terrestrial and satellite communication system performance. This research developed new individually-reconfigurable planar antenna array elements that can be adjusted to provide multiple beams while providing increased scan angles and higher aperture efficiency than traditional diffraction-limited arrays. These new elements are microstrip spiral antennas with specialized tuning mechanisms that provide adjustable radiation patterns. We anticipate that these new elements can be used in both large and small arrays for inter-satellite communication as well as tracking of multiple mobile surface-based units. Our work has developed both theoretical descriptions as well as experimental prototypes of the antennas in both single element and array embodiments. The technical summary of the results of this work is divided into six sections: A. Cavity model for analysis and design of pattern reconfigurable antennas; B. Performance of antenna in array configurations for broadside and endfire operation; C. Performance of antenna in array configurations for beam scanning operation; D. Simulation of antennas in infinite phased arrays; E. Demonstration of antenna with commercially-available RF MEMS switches; F. Design of antenna MEMS switch combinations for direct simultaneous fabrication.

Modeling methods of MEMS micro-speaker with electrostatic working principle

NASA Astrophysics Data System (ADS)

Tumpold, D.; Kaltenbacher, M.; Glacer, C.; Nawaz, M.; Dehé, A.

2013-05-01

The market for mobile devices like tablets, laptops or mobile phones is increasing rapidly. Device housings get thinner and energy efficiency is more and more important. Micro-Electro-Mechanical-System (MEMS) loudspeakers, fabricated in complementary metal oxide semiconductor (CMOS) compatible technology merge energy efficient driving technology with cost economical fabrication processes. In most cases, the fabrication of such devices within the design process is a lengthy and costly task. Therefore, the need for computer modeling tools capable of precisely simulating the multi-field interactions is increasing. The accurate modeling of such MEMS devices results in a system of coupled partial differential equations (PDEs) describing the interaction between the electric, mechanical and acoustic field. For the efficient and accurate solution we apply the Finite Element (FE) method. Thereby, we fully take the nonlinear effects into account: electrostatic force, charged moving body (loaded membrane) in an electric field, geometric nonlinearities and mechanical contact during the snap-in case between loaded membrane and stator. To efficiently handle the coupling between the mechanical and acoustic fields, we apply Mortar FE techniques, which allow different grid sizes along the coupling interface. Furthermore, we present a recently developed PML (Perfectly Matched Layer) technique, which allows limiting the acoustic computational domain even in the near field without getting spurious reflections. For computations towards the acoustic far field we us a Kirchhoff Helmholtz integral (e.g, to compute the directivity pattern). We will present simulations of a MEMS speaker system based on a single sided driving mechanism as well as an outlook on MEMS speakers using double stator systems (pull-pull-system), and discuss their efficiency (SPL) and quality (THD) towards the generated acoustic sound.

Finite Element Modeling of Micromachined MEMS Photon Devices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Datskos, P.G.; Evans, B.M.; Schonberger, D.

1999-09-20

The technology of microelectronics that has evolved over the past half century is one of great power and sophistication and can now be extended to many applications (MEMS and MOEMS) other than electronics. An interesting application of MEMS quantum devices is the detection of electromagnetic radiation. The operation principle of MEMS quantum devices is based on the photoinduced stress in semiconductors, and the photon detection results from the measurement of the photoinduced bending. These devices can be described as micromechanical photon detectors. In this work, we have developed a technique for simulating electronic stresses using finite element analysis. We havemore » used our technique to model the response of micromechanical photon devices to external stimuli and compared these results with experimental data. Material properties, geometry, and bimaterial design play an important role in the performance of micromechanical photon detectors. We have modeled these effects using finite element analysis and included the effects of bimaterial thickness coating, effective length of the device, width, and thickness.« less

Development of High Precision Metal Micro-Electro-Mechanical-Systems Column for Portable Surface Acoustic Wave Gas Chromatograph

NASA Astrophysics Data System (ADS)

Iwaya, Takamitsu; Akao, Shingo; Sakamoto, Toshihiro; Tsuji, Toshihiro; Nakaso, Noritaka; Yamanaka, Kazushi

2012-07-01

In the field of environmental measurement and security, a portable gas chromatograph (GC) is required for the on-site analysis of multiple hazardous gases. Although the gas separation column has been downsized using micro-electro-mechanical-systems (MEMS) technology, an MEMS column made of silicon and glass still does not have sufficient robustness and a sufficiently low fabrication cost for a portable GC. In this study, we fabricated a robust and inexpensive high-precision metal MEMS column by combining diffusion-bonded etched stainless-steel plates with alignment evaluation using acoustic microscopy. The separation performance was evaluated using a desktop GC with a flame ionization detector and we achieved the high separation performance comparable to the best silicon MEMS column fabricated using a dynamic coating method. As an application, we fabricated a palm-size surface acoustic wave (SAW) GC combining this column with a ball SAW sensor and succeeded in separating and detecting a mixture of volatile organic compounds.

Finite element modeling of micromachined MEMS photon devices

NASA Astrophysics Data System (ADS)

Evans, Boyd M., III; Schonberger, D. W.; Datskos, Panos G.

1999-09-01

The technology of microelectronics that has evolved over the past half century is one of great power and sophistication and can now be extended to many applications (MEMS and MOEMS) other than electronics. An interesting application of MEMS quantum devices is the detection of electromagnetic radiation. The operation principle of MEMS quantum devices is based on the photoinduced stress in semiconductors, and the photon detection results from the measurement of the photoinduced bending. These devices can be described as micromechanical photon detectors. In this work, we have developed a technique for simulating electronic stresses using finite element analysis. We have used our technique to model the response of micromechanical photon devices to external stimuli and compared these results with experimental data. Material properties, geometry, and bimaterial design play an important role in the performance of micromechanical photon detectors. We have modeled these effects using finite element analysis and included the effects of bimaterial thickness coating, effective length of the device, width, and thickness.

High Volume Manufacturing and Field Stability of MEMS Products

NASA Astrophysics Data System (ADS)

Martin, Jack

Low volume MEMS/NEMS production is practical when an attractive concept is implemented with business, manufacturing, packaging, and test support. Moving beyond this to high volume production adds requirements on design, process control, quality, product stability, market size, market maturity, capital investment, and business systems. In a broad sense, this chapter uses a case study approach: It describes and compares the silicon-based MEMS accelerometers, pressure sensors, image projection systems, and gyroscopes that are in high volume production. Although they serve several markets, these businesses have common characteristics. For example, the manufacturing lines use automated semiconductor equipment and standard material sets to make consistent products in large quantities. Standard, well controlled processes are sometimes modified for a MEMS product. However, novel processes that cannot run with standard equipment and material sets are avoided when possible. This reliance on semiconductor tools, as well as the organizational practices required to manufacture clean, particle-free products partially explains why the MEMS market leaders are integrated circuit manufacturers. There are other factors. MEMS and NEMS are enabling technologies, so it can take several years for high volume applications to develop. Indeed, market size is usually a strong function of price. This becomes a vicious circle, because low price requires low cost - a result that is normally achieved only after a product is in high volume production. During the early years, IC companies reduced cost and financial risk by using existing facilities for low volume MEMS production. As a result, product architectures are partially determined by capabilities developed for previous products. This chapter includes a discussion of MEMS product architecture with particular attention to the impact of electronic integration, packaging, and surfaces. Packaging and testing are critical, because they are significant factors in MEMS product cost. These devices have extremelyhigh surface/volume ratios, so performance and stability may depend on the control of surface characteristics after packaging. Looking into the future, the competitive advantage of IC suppliers will decrease as small companies learn to integrate MEMS/NEMS devices on CMOS foundry wafers. Packaging challenges still remain, because most MEMS/NEMS products must interact with the environment without degrading stability or reliability. Generic packaging solutions are unlikely. However, packaging subcontractors recognize that MEMS/NEMS is a growth opportunity. They will spread the overhead burden of high-capital-cost-facilities by developing flexible processes in order to package several types of moderate volume integrated MEMS/NEMS products on the same equipment.

High Volume Manufacturing and Field Stability of MEMS Products

NASA Astrophysics Data System (ADS)

Martin, Jack

Low volume MEMS/NEMS production is practical when an attractive concept is implemented with business, manufacturing, packaging, and test support. Moving beyond this to high volume production adds requirements on design, process control, quality, product stability, market size, market maturity, capital investment, and business systems. In a broad sense, this chapter uses a case study approach: It describes and compares the silicon-based MEMS accelerometers, pressure sensors, image projection systems, and gyroscopes that are in high volume production. Although they serve several markets, these businesses have common characteristics. For example, the manufacturing lines use automated semiconductor equipment and standard material sets to make consistent products in large quantities. Standard, well controlled processes are sometimes modified for a MEMS product. However, novel processes that cannot run with standard equipment and material sets are avoided when possible. This reliance on semiconductor tools, as well as the organizational practices required to manufacture clean, particle-free products partially explains why the MEMS market leaders are integrated circuit manufacturers. There are other factors. MEMS and NEMS are enabling technologies, so it can take several years for high volume applications to develop. Indeed, market size is usually a strong function of price. This becomes a vicious circle, because low price requires low cost - a result that is normally achieved only after a product is in high volume production. During the early years, IC companies reduced cost and financial risk by using existing facilities for low volume MEMS production. As a result, product architectures are partially determined by capabilities developed for previous products. This chapter includes a discussion of MEMS product architecture with particular attention to the impact of electronic integration, packaging, and surfaces. Packaging and testing are critical, because they are significant factors in MEMS product cost. These devices have extremely high surface/volume ratios, so performance and stability may depend on the control of surface characteristics after packaging. Looking into the future, the competitive advantage of IC suppliers will decrease as small companies learn to integrate MEMS/NEMS devices on CMOS foundry wafers. Packaging challenges still remain, because most MEMS/NEMS products must interact with the environment without degrading stability or reliability. Generic packaging solutions are unlikely. However, packaging subcontractors recognize that MEMS/NEMS is a growth opportunity. They will spread the overhead burden of high-capital-cost-facilities by developing flexible processes in order to package several types of moderate volume integrated MEMS/NEMS products on the same equipment.

Nanocharacterization of the adhesion effect and bending stiffness in optical MEMS

NASA Astrophysics Data System (ADS)

Pustan, Marius; Birleanu, Corina; Dudescu, Cristian

2017-11-01

The scope of this paper is the reliability design and testing of flexible MEMS components as clamp-clamp beams for the out-of-plane displacement. The field of implementation of such structures is in optical relevant applications such as the optical microsensors or optical microswitches. Moreover these structures can be successfully implemented in RF switches or in the other MEMS applications. The research studies presented in this paper consider the analytical and numerical analysis follow by the experimental validation. The mechanical and tribological characteristics such as the sample static response under an applied force and the adhesion effect between the flexible structure and substrate are investigated. The samples under test are fabricated from a reflective material - gold. Experimental investigations are performed by atomic force microscopy in order to determine the response of the gold microbridges under an applied force. Moreover, to identify the proper geometry that is less sensitive to a thermal gradient, different geometrical configurations of microbridges are tested under different temperatures. An etalon structure is considered as a reference beam and it is compared with the other samples fabricated in the same geometrical dimensions but with some additional rectangular holes performed on the flexible plate. The scope of holes is to reduce the temperature influence on the mechanical behaviour of clamp-clamp beam from application where a thermal gradient occurs. During numerical analysis and experimental investigations, the temperature of samples is increased from 20 °C to 100 °C and the sample response is monitored. A comparison between numerical and experimental results is provided at the end of paper. The research results are useful for designers to predict the behaviour of material and structure from optical or thermal applications in order to improve the reliability and the MEMS lifetime.

[A micro-silicon multi-slit spectrophotometer based on MEMS technology].

PubMed

Hao, Peng; Wu, Yi-Hui; Zhang, Ping; Liu, Yong-Shun; Zhang, Ke; Li, Hai-Wen

2009-06-01

A new mini-spectrophotometer was developed by adopting micro-silicon slit and pixel segmentation technology, and this spectrophotometer used photoelectron diode array as the detector by the back-dividing-light way. At first, the effect of the spectral bandwidth on the tested absorbance linear correlation was analyzed. A theory for the design of spectrophotometer's slit was brought forward after discussing the relationships between spectrophotometer spectrum band width and pre-and post-slits width. Then, the integrative micro-silicon-slit, which features small volume, high precision, and thin thickness, was manufactured based on the MEMS technology. Finally, a test was carried on linear absorbance solution by this spectrophotometer. The final result showed that the correlation coefficients were larger than 0.999, which means that the new mini-spectrophotometer with micro-silicon slit pixel segmentation has an obvious linear correlation.

Design and Fabrication of a Miniaturized GMI Magnetic Sensor Based on Amorphous Wire by MEMS Technology

PubMed Central

Chen, Jiawen; Li, Jianhua; Li, Yiyuan; Chen, Yulong

2018-01-01

A miniaturized Co-based amorphous wire GMI (Giant magneto-impedance) magnetic sensor was designed and fabricated in this paper. The Co-based amorphous wire was used as the sense element due to its high sensitivity to the magnetic field. A three-dimensional micro coil surrounding the Co-based amorphous wire was fabricated by MEMS (Micro-Electro-Mechanical System) technology, which was used to extract the electrical signal. The three-dimensional micro pick-up coil was designed and simulated with HFSS (High Frequency Structure Simulator) software to determine the key parameters. Surface micro machining MEMS (Micro-Electro-Mechanical System) technology was employed to fabricate the three-dimensional coil. The size of the developed amorphous wire magnetic sensor is 5.6 × 1.5 × 1.1 mm3. Helmholtz coil was used to characterize the performance of the device. The test results of the sensor sample show that the voltage change is 130 mV/Oe and the linearity error is 4.83% in the range of 0~45,000 nT. The results indicate that the developed miniaturized magnetic sensor has high sensitivity. By testing the electrical resistance of the samples, the results also showed high uniformity of each device. PMID:29494477

MEMS packaging: state of the art and future trends

NASA Astrophysics Data System (ADS)

Bossche, Andre; Cotofana, Carmen V. B.; Mollinger, Jeff R.

1998-07-01

Now that the technology for Integrated sensor and MEMS devices has become sufficiently mature to allow mass production, it is expected that the prices of bare chips will drop dramatically. This means that the package prices will become a limiting factor in market penetration, unless low cost packaging solutions become available. This paper will discuss the developments in packaging technology. Both single-chip and multi-chip packaging solutions will be addressed. It first starts with a discussion on the different requirements that have to be met; both from a device point of view (open access paths to the environment, vacuum cavities, etc.) and from the application point of view (e.g. environmental hostility). Subsequently current technologies are judged on their applicability for MEMS and sensor packaging and a forecast is given for future trends. It is expected that the large majority of sensing devices will be applied in relative friendly environments for which plastic packages would suffice. Therefore, on the short term an important role is foreseen for recently developed plastic packaging techniques such as precision molding and precision dispensing. Just like in standard electronic packaging, complete wafer level packaging methods for sensing devices still have a long way to go before they can compete with the highly optimized and automated plastic packaging processes.

MEMS Technology for Space Applications

NASA Technical Reports Server (NTRS)

vandenBerg, A.; Spiering, V. L.; Lammerink, T. S. J.; Elwenspoek, M.; Bergveld, P.

1995-01-01

Micro-technology enables the manufacturing of all kinds of components for miniature systems or micro-systems, such as sensors, pumps, valves, and channels. The integration of these components into a micro-electro-mechanical system (MEMS) drastically decreases the total system volume and mass. These properties, combined with the increasing need for monitoring and control of small flows in (bio)chemical experiments, makes MEMS attractive for space applications. The level of integration and applied technology depends on the product demands and the market. The ultimate integration is process integration, which results in a one-chip system. An example of process integration is a dosing system of pump, flow sensor, micromixer, and hybrid feedback electronics to regulate the flow. However, for many applications, a hybrid integration of components is sufficient and offers the advantages of design flexibility and even the exchange of components in the case of a modular set up. Currently, we are working on hybrid integration of all kinds of sensors (physical and chemical) and flow system modules towards a modular system; the micro total analysis system (micro TAS). The substrate contains electrical connections as in a printed circuit board (PCB) as well as fluid channels for a circuit channel board (CCB) which, when integrated, form a mixed circuit board (MCB).

Application of MEMS Microphone Array Technology to Airframe Noise Measurements

NASA Technical Reports Server (NTRS)

Humphreys, William M., Jr.; Shams, Qamar A.; Graves, Sharon S.; Sealey, Bradley S.; Bartram, Scott M.; Comeaux, Toby

2005-01-01

Current generation microphone directional array instrumentation is capable of extracting accurate noise source location and directivity data on a variety of aircraft components, resulting in significant gains in test productivity. However, with this gain in productivity has come the desire to install larger and more complex arrays in a variety of ground test facilities, creating new challenges for the designers of array systems. To overcome these challenges, a research study was initiated to identify and develop hardware and fabrication technologies which could be used to construct an array system exhibiting acceptable measurement performance but at much lower cost and with much simpler installation requirements. This paper describes an effort to fabricate a 128-sensor array using commercially available Micro-Electro-Mechanical System (MEMS) microphones. The MEMS array was used to acquire noise data for an isolated 26%-scale high-fidelity Boeing 777 landing gear in the Virginia Polytechnic Institute and State University Stability Tunnel across a range of Mach numbers. The overall performance of the array was excellent, and major noise sources were successfully identified from the measurements.

Operational characterization of CSFH MEMS technology based hinges

NASA Astrophysics Data System (ADS)

Crescenzi, Rocco; Balucani, Marco; Belfiore, Nicola Pio

2018-05-01

Progress in MEMS technology continuously stimulates new developments in the mechanical structure of micro systems, such as, for example, the concept of so-called CSFH (conjugate surfaces flexural hinge), which makes it possible, simultaneously, to minimize the internal stresses and to increase motion range and robustness. Such a hinge may be actuated by means of a rotary comb-drive, provided that a proper set of simulations and tests are capable to assess its feasibility. In this paper, a CSFH has been analyzed with both theoretical and finite element (FEM) methods, in order to obtain the relation between voltage and generated torque. The FEM model considers also the fringe effect on the comb drive finger. Electromechanical couple-field analysis is performed by means of both direct and load transfer methods. Experimental tests have been also performed on a CSFH embedded in a MEMS prototype, which has been fabricated starting from a SOI wafer and using D-RIE (deep reactive ion etching). Results showed that CSFH performs better than linear flexure hinges in terms of larger rotations and less stress for given applied voltage.

A Low-Cost CMOS-MEMS Piezoresistive Accelerometer with Large Proof Mass

PubMed Central

Khir, Mohd Haris Md; Qu, Peng; Qu, Hongwei

2011-01-01

This paper reports a low-cost, high-sensitivity CMOS-MEMS piezoresistive accelerometer with large proof mass. In the device fabricated using ON Semiconductor 0.5 μm CMOS technology, an inherent CMOS polysilicon thin film is utilized as the piezoresistive sensing material. A full Wheatstone bridge was constructed through easy wiring allowed by the three metal layers in the 0.5 μm CMOS technology. The device fabrication process consisted of a standard CMOS process for sensor configuration, and a deep reactive ion etching (DRIE) based post-CMOS microfabrication for MEMS structure release. A bulk single-crystal silicon (SCS) substrate is included in the proof mass to increase sensor sensitivity. In device design and analysis, the self heating of the polysilicon piezoresistors and its effect to the sensor performance is also discussed. With a low operating power of 1.5 mW, the accelerometer demonstrates a sensitivity of 0.077 mV/g prior to any amplification. Dynamic tests have been conducted with a high-end commercial calibrating accelerometer as reference. PMID:22164052

Novel threshold pressure sensors based on nonlinear dynamics of MEMS resonators

NASA Astrophysics Data System (ADS)

Hasan, Mohammad H.; Alsaleem, Fadi M.; Ouakad, Hassen M.

2018-06-01

Triggering an alarm in a car for low air-pressure in the tire or tripping an HVAC compressor if the refrigerant pressure is lower than a threshold value are examples for applications where measuring the amount of pressure is not as important as determining if the pressure has exceeded a threshold value for an action to occur. Unfortunately, current technology still relies on analog pressure sensors to perform this functionality by adding a complex interface (extra circuitry, controllers, and/or decision units). In this paper, we demonstrate two new smart tunable-threshold pressure switch concepts that can reduce the complexity of a threshold pressure sensor. The first concept is based on the nonlinear subharmonic resonance of a straight double cantilever microbeam with a proof mass and the other concept is based on the snap-through bi-stability of a clamped-clamped MEMS shallow arch. In both designs, the sensor operation concept is simple. Any actuation performed at a certain pressure lower than a threshold value will activate a nonlinear dynamic behavior (subharmonic resonance or snap-through bi-stability) yielding a large output that would be interpreted as a logic value of ONE, or ON. Once the pressure exceeds the threshold value, the nonlinear response ceases to exist, yielding a small output that would be interpreted as a logic value of ZERO, or OFF. A lumped, single degree of freedom model for the double cantilever beam, that is validated using experimental data, and a continuous beam model for the arch beam, are used to simulate the operation range of the proposed sensors by identifying the relationship between the excitation signal and the critical cut-off pressure.

Micro-Raman Analysis of Irradiated Diamond Films

NASA Technical Reports Server (NTRS)

Newton, R. L.; Munafo, Paul M. (Technical Monitor)

2002-01-01

Owing to its unique and robust physical properties, diamond is a much sought after material for use in advanced technologies such as Microelectromechanical Systems (MEMS). The volume and weight savings promised by MEMS-based devices are of particular interest to spaceflight applications. However, much basic materials science research remains to be completed in this field. Results of micro-Raman analysis of proton (1015 - 1017 H+/cm2 doses) irradiated chemical vapor deposited (CVD) diamond reveals that the microstructure is retained even after high radiation exposure.

Micro-electro-mechanical systems (MEMS) and agile lensing-based modules for communications, sensing and signal processing

NASA Astrophysics Data System (ADS)

Reza, Syed Azer

This dissertation proposes the use of the emerging Micro-Electro-Mechanical Systems (MEMS) and agile lensing optical device technologies to design novel and powerful signal conditioning and sensing modules for advanced applications in optical communications, physical parameter sensing and RF/optical signal processing. For example, these new module designs have experimentally demonstrated exceptional features such as stable loss broadband operations and high > 60 dB optical dynamic range signal filtering capabilities. The first part of the dissertation describes the design and demonstration of digital MEMS-based signal processing modules for communication systems and sensor networks using the TI DLP (Digital Light Processing) technology. Examples of such modules include optical power splitters, narrowband and broadband variable fiber optical attenuators, spectral shapers and filters. Compared to prior works, these all-digital designs have advantages of repeatability, accuracy, and reliability that are essential for advanced communications and sensor applications. The next part of the dissertation proposes, analyzes and demonstrates the use of analog opto-fluidic agile lensing technology for sensor networks and test and measurement systems. Novel optical module designs for distance sensing, liquid level sensing, three-dimensional object shape sensing and variable photonic delay lines are presented and experimentally demonstrated. Compared to prior art module designs, the proposed analog-mode modules have exceptional performances, particularly for extreme environments (e.g., caustic liquids) where the free-space agile beam-based sensor provide remote non-contact access for physical sensing operations. The dissertation also presents novel modules involving hybrid analog-digital photonic designs that make use of the different optical device technologies to deliver the best features of both analog and digital optical device operations and controls. Digital controls are achieved through the use of the digital MEMS technology and analog controls are realized by employing opto-fluidic agile lensing technology and acousto-optic technology. For example, variable fiber-optic attenuators and spectral filters are proposed using the hybrid design. Compared to prior art module designs, these hybrid designs provide a higher module dynamic range and increased resolution that are critical in various advanced system applications. In summary, the dissertation shows the added power of hybrid optical designs using both the digital and analog photonic signal processing versus just all-digital or all-analog module designs.

New technologies for the actuation and controls of large aperture lightweight quality mirrors

NASA Technical Reports Server (NTRS)

Lih, S. S.; Yang, E. H.; Gullapalli, S. N.; Flood, R.

2003-01-01

This paper presents a set of candidate components: MEMS based large stroke (>100 microns) ultra lightweight (0.01 gm) discrete inch worm actuator technology, and a distributed actuator technology, in the context of a novel lightweight active flexure-hinged substrate concept that uses the nanolaminate face sheet.

GRC-2011-C-00579

NASA Image and Video Library

2007-03-28

Photos for Web Feature by Victoria (Tori) Woods; Micro-Electro Mechanical Systems (MEMS) using vacuum technology; fabricating High Temperature Electronics for Harsh Environments using silicon carbide substrates

MEMS-based platforms for mechanical manipulation and characterization of cells

NASA Astrophysics Data System (ADS)

Pan, Peng; Wang, Wenhui; Ru, Changhai; Sun, Yu; Liu, Xinyu

2017-12-01

Mechanical manipulation and characterization of single cells are important experimental techniques in biological and medical research. Because of the microscale sizes and highly fragile structures of cells, conventional cell manipulation and characterization techniques are not accurate and/or efficient enough or even cannot meet the more and more demanding needs in different types of cell-based studies. To this end, novel microelectromechanical systems (MEMS)-based technologies have been developed to improve the accuracy, efficiency, and consistency of various cell manipulation and characterization tasks, and enable new types of cell research. This article summarizes existing MEMS-based platforms developed for cell mechanical manipulation and characterization, highlights their specific design considerations making them suitable for their designated tasks, and discuss their advantages and limitations. In closing, an outlook into future trends is also provided.

Dynamic focus-tracking MEMS scanning micromirror with low actuation voltages for endoscopic imaging.

PubMed

Strathman, Matthew; Liu, Yunbo; Li, Xingde; Lin, Lih Y

2013-10-07

We demonstrate a 3-D scanning micromirror device that combines 2-D beam scanning with focus control in the same device using micro-electro-mechanical-systems (MEMS) technology. 2-D beam scanning is achieved with a biaxial gimbal structure and focus control is obtained with a deformable mirror membrane surface. The micromirror with 800 micrometer diameter is designed to be sufficiently compact and efficient so that it can be incorporated into an endoscopic imaging probe in the future. The design, fabrication and characterization of the device are described in this paper. Using the focus-tracking MEMS scanning mirror, we achieved an optical scanning range of >16 degrees with <40 V actuation voltage at resonance and a tunable focal length between infinity and 25 mm with <100V applied bias.

Method for measuring thermal accommodation coefficients of gases on thin film surfaces using a MEMS sensor structure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grau, Mario, E-mail: mario.grau@hs-rm.de; Völklein, Friedemann; Meier, Andreas

A method for measuring the thermal accommodation coefficient α for surface-/gas interfaces is presented. It allows the determination of α for thin films produced by a variety of deposition technologies, such as chemical vapor deposition, physical vapor deposition, and atomic layer deposition (ALD). The setup is based on two microelectromechanical systems (MEMS) Pirani sensors facing each other in a defined positioning. Because these MEMS sensors show a very high sensitivity in their individual molecular flow regimes, it is possible to measure the accommodation coefficients of gases without the disturbing influence of the transition regime. This paper presents the analytical backgroundmore » and the actual measurement principle. The results for air and nitrogen molecules on sputtered Au and Pt surfaces are presented.« less

Three Axes MEMS Combined Sensor for Electronic Stability Control System

NASA Astrophysics Data System (ADS)

Jeong, Heewon; Goto, Yasushi; Aono, Takanori; Nakamura, Toshiaki; Hayashi, Masahide

A microelectromechanical systems (MEMS) combined sensor measuring two-axis accelerations and an angular rate (rotation) has been developed for an electronic stability control system of automobiles. With the recent trend to mount the combined sensors in the engine compartment, the operation temperature range increased drastically, with the request of immunity to environmental disturbances such as vibration. In this paper, we report the combined sensor which has a gyroscopic part and two acceleration parts in single die. A deformation-robust MEMS structure has been adopted to achieve stable operation under wide temperature range (-40 to 125°C) in the engine compartment. A package as small as 10 × 19 × 4 mm is achieved by adopting TSV (through silicon via) and WLP (wafer-level package) technologies with enough performance as automotive grade.

MEMS Microshutter Arrays for James Webb Space Telescope

NASA Technical Reports Server (NTRS)

Li, Mary J.; Beamesderfer, Michael; Babu, Sachi; Bajikar, Sateesh; Ewin, Audrey; Franz, Dave; Hess, Larry; Hu, Ron; Jhabvala, Murzy; Kelly, Dan;

Glassy carbon MEMS for novel origami-styled 3D integrated intracortical and epicortical neural probes

NASA Astrophysics Data System (ADS)

Goshi, Noah; Castagnola, Elisa; Vomero, Maria; Gueli, Calogero; Cea, Claudia; Zucchini, Elena; Bjanes, David; Maggiolini, Emma; Moritz, Chet; Kassegne, Sam; Ricci, Davide; Fadiga, Luciano

2018-06-01

We report on a novel technology for microfabricating 3D origami-styled micro electro-mechanical systems (MEMS) structures with glassy carbon (GC) features and a supporting polymer substrate. GC MEMS devices that open to form 3D microstructures are microfabricated from GC patterns that are made through pyrolysis of polymer precursors on high-temperature resisting substrates like silicon or quartz and then transferring the patterned devices to a flexible substrate like polyimide followed by deposition of an insulation layer. The devices on flexible substrate are then folded into 3D form in an origami-fashion. These 3D MEMS devices have tunable mechanical properties that are achieved by selectively varying the thickness of the polymeric substrate and insulation layers at any desired location. This technology opens new possibilities by enabling microfabrication of a variety of 3D GC MEMS structures suited to applications ranging from biochemical sensing to implantable microelectrode arrays. As a demonstration of the technology, a neural signal recording microelectrode array platform that integrates both surface (cortical) and depth (intracortical) GC microelectrodes onto a single flexible thin-film device is introduced. When the device is unfurled, a pre-shaped shank of polyimide automatically comes off the substrate and forms the penetrating part of the device in a 3D fashion. With the advantage of being highly reproducible and batch-fabricated, the device introduced here allows for simultaneous recording of electrophysiological signals from both the brain surface (electrocorticography—ECoG) and depth (single neuron). Our device, therefore, has the potential to elucidate the roles of underlying neurons on the different components of µECoG signals. For in vivo validation of the design capabilities, the recording sites are coated with a poly(3,4-ethylenedioxythiophene)—polystyrene sulfonate—carbon nanotube composite, to improve the electrical conductivity of the electrodes and consequently the quality of the recorded signals. Results show that both µECoG and intracortical arrays were able to acquire neural signals with high-sensitivity that increased with depth, thereby verifying the device functionality.

PREFACE: The 15th International Conference on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2015)

NASA Astrophysics Data System (ADS)

Livermore, C.; Velásquez-García, L. F.

2015-12-01

Greetings, and welcome to Boston, MA and PowerMEMS 2015 - the 15th International Conference on Micro and Nanotechnology for Power Generation and Energy Conversion Applications! The objective of PowerMEMS 2015 is to catalyze innovation in micro- and nano-scale technologies for the energy domain. The scope of the meeting ranges from basic principles, to materials and fabrication, to devices and systems, to applications. The many applications of Power MEMS range from the harvesting, storage, conversion and conditioning of energy, to integrated systems that manage these processes, to actuation, pumping, and propulsion. Our Conference aims to stimulate the exchange of insights and information, as well as the development of new ideas, in the Power MEMS field. Our goal is to allow the attendees to interact and network within our multidisciplinary community that includes professionals from many branches of science and engineering, as well as energy, policy, and entrepreneurial specialists interested in the commercialization of Power MEMS technologies. Since the first PowerMEMS in Sendai, Japan in 2000, the Conference has grown in size, reputation, impact, and technical breadth. This continuing growth is evident in this year's technical program, which includes an increasing number of papers on nanomaterials, additive manufacturing for energy systems, actuators, energy storage, harvesting strategies and integrated energy harvesting systems, for example. This year's technical program is highlighted by six plenary talks from prominent experts on piezoelectrics, robotic insects, thermoelectrics, photovoltaics, nanocomposite cathodes, and thermal energy conversion systems. The contributed program received a large number of abstract submissions this year, 169 in total. After careful review by the 34-member Technical Program Committee, a total of 135 papers were selected for presentation. The 60 contributed oral presentations are arranged in two parallel sessions. The 75 posters are arranged in a ''two-in-one'' poster session in which the poster session time is divided in two; half the posters will be presented during each half-session, allowing the poster presenters to also browse the posters during the poster session. Posters will remain up during the meeting, so please feel free to peruse them at your leisure. The Proceedings will be visible and accessible through IOP after conclusion of the Conference. We hope to maximize interaction among participants and stimulate lively discussion through the technical program and social events. For the first time at the Conference, a great many sponsors are making their presence known at PowerMEMS through tabletop displays, which will catalyze engaging conversations between our industrial partners and the research community. Also, for the first time at PowerMEMS, we will host a Rump Session - an informal event in which Conference participants engage in honest and fun discussions of topics of relevance to the community while strengthening bonds within the community. This meeting is made possible by many generous contributions of time, effort, and financial support. Thanks are due to the Technical Program Committee for their intensive efforts in reviewing abstract submissions, and to the International Steering Committee for their advice and support. We are grateful to Preferred Meeting Management Inc. for their many and key contributions to the management and organization of our Conference. Finally, we gratefully acknowledge the organizational and financial support provided for this meeting by the Transducers Research Foundation, Northeastern University, the Massachusetts Institute of Technology, and our exhibitors and other supporters. We hope that you find our Conference enjoyable and fruitful, and that you enjoy your stay in the Boston, MA area.

Microwave photonic filters using low-cost sources featuring tunability, reconfigurability and negative coefficients.

PubMed

Capmany, José; Mora, José; Ortega, Beatriz; Pastor, Daniel

2005-03-07

We propose and experimentally demonstrate two configurations of photonic filters for the processing of microwave signals featuring tunability, reconfigurability and negative coefficients based on the use of low cost optical sources. The first option is a low power configuration based on spectral slicing of a broadband source. The second is a high power configuration based on fixed lasers. Tunability, reconfigurability and negative coefficients are achieved by means of a MEMS cross-connect, a variable optical attenuator array and simple 2x2 switches respectively.

The MEMS Knudsen Compressor as a Vacuum Pump for Space Exploration Applications

NASA Technical Reports Server (NTRS)

Vargo, S. E.; Muntz, E. P.; Tang, W. C.

2000-01-01

Several lander, probe and rover missions currently under study at the Jet Propulsion Laboratory (JPL) and especially in the Microdevices Laboratory (MDL) Center for Space Microelectronics Technology, focus on utilizing microelectromechanical systems (MEMS) based instruments for science data gathering. These small instruments and NASA's commitment to "faster, better, cheaper" type missions has brought about the need for novel approaches to satisfying mission requirements. Existing in-situ instrument systems clearly lack novel and integrated methods for satisfying their vacuum needs. One attractive candidate for a MEMS vacuum pump is the Knudsen Compressor, which operates based on thermal transpiration. Thermal transpiration describes gas flows induced by temperature differences maintained across orifices, porous membranes or capillary tubes under rarefied conditions. This device has two overwhelmingly attractive features as a MEMS vacuum pump - no moving parts and no fluids. An initial estimate of a Knudsen Compressor's pumping power requirements for a surface atmospheric sampling task on Mars is less than 80 mW, significantly below than alternative pumps. Due to the relatively low energy use for this task and the applicability of the Knudsen Compressor to other applications, the development of a Knudsen Compressor utilizing MEMS fabrication techniques has been initiated. This paper discusses the initial fabrication of a single-stage MEMS Knudsen Compressor vacuum pump, provides performance criteria such as pumping speed, size, energy use and ultimate pressure and details vacuum pump applications in several MDL related in-situ instruments.

UAV-borne lidar with MEMS mirror-based scanning capability

NASA Astrophysics Data System (ADS)

Kasturi, Abhishek; Milanovic, Veljko; Atwood, Bryan H.; Yang, James

2016-05-01

Firstly, we demonstrated a wirelessly controlled MEMS scan module with imaging and laser tracking capability which can be mounted and flown on a small UAV quadcopter. The MEMS scan module was reduced down to a small volume of <90mm x 60mm x 40mm, weighing less than 40g and consuming less than 750mW of power using a ~5mW laser. This MEMS scan module was controlled by a smartphone via Bluetooth while flying on a drone, and could project vector content, text, and perform laser based tracking. Also, a "point-and-range" LiDAR module was developed for UAV applications based on low SWaP (Size, Weight and Power) gimbal-less MEMS mirror beam-steering technology and off-the-shelf OEM LRF modules. For demonstration purposes of an integrated laser range finder module, we used a simple off-the-shelf OEM laser range finder (LRF) with a 100m range, +/-1.5mm accuracy, and 4Hz ranging capability. The LRFs receiver optics were modified to accept 20° of angle, matching the transmitter's FoR. A relatively large (5.0mm) diameter MEMS mirror with +/-10° optical scanning angle was utilized in the demonstration to maintain the small beam divergence of the module. The complete LiDAR prototype can fit into a small volume of <70mm x 60mm x 60mm, and weigh <50g when powered by the UAV's battery. The MEMS mirror based LiDAR system allows for ondemand ranging of points or areas within the FoR without altering the UAV's position. Increasing the LRF ranging frequency and stabilizing the pointing of the laser beam by utilizing the onboard inertial sensors and the camera are additional goals of the next design.

On the feasibility to integrate low-cost MEMS accelerometers and GNSS receivers

NASA Astrophysics Data System (ADS)

Benedetti, Elisa; Dermanis, Athanasios; Crespi, Mattia

2017-06-01

The aim of this research was to investigate the feasibility of merging the benefits offered by low-cost GNSS and MEMS accelerometers technology, in order to promote the diffusion of low-cost monitoring solutions. A merging approach was set up at the level of the combination of kinematic results (velocities and displacements) coming from the two kinds of sensors, whose observations were separately processed, following to the so called loose integration, which sounds much more simple and flexible thinking about the possibility of an easy change of the combined sensors. At first, the issues related to the difference in reference systems, time systems and measurement rate and epochs for the two sensors were faced with. An approach was designed and tested to transform into unique reference and time systems the outcomes from GPS and MEMS and to interpolate the usually (much) more dense MEMS observation to common (GPS) epochs. The proposed approach was limited to time-independent (constant) orientation of the MEMS reference system with respect to the GPS one. Then, a data fusion approach based on the use of Discrete Fourier Transform and cubic splines interpolation was proposed both for velocities and displacements: MEMS and GPS derived solutions are firstly separated by a rectangular filter in spectral domain, and secondly back-transformed and combined through a cubic spline interpolation. Accuracies around 5 mm for slow and fast displacements and better than 2 mm/s for velocities were assessed. The obtained solution paves the way to a powerful and appealing use of low-cost single frequency GNSS receivers and MEMS accelerometers for structural and ground monitoring applications. Some additional remarks and prospects for future investigations complete the paper.

Benefits of combined GPS/GLONASS with low-cost MEMS IMUs for vehicular urban navigation.

PubMed

Angrisano, Antonio; Petovello, Mark; Pugliano, Giovanni

2012-01-01

The integration of Global Navigation Satellite Systems (GNSS) with Inertial Navigation Systems (INS) has been very actively researched for many years due to the complementary nature of the two systems. In particular, during the last few years the integration with micro-electromechanical system (MEMS) inertial measurement units (IMUs) has been investigated. In fact, recent advances in MEMS technology have made possible the development of a new generation of low cost inertial sensors characterized by small size and light weight, which represents an attractive option for mass-market applications such as vehicular and pedestrian navigation. However, whereas there has been much interest in the integration of GPS with a MEMS-based INS, few research studies have been conducted on expanding this application to the revitalized GLONASS system. This paper looks at the benefits of adding GLONASS to existing GPS/INS(MEMS) systems using loose and tight integration strategies. The relative benefits of various constraints are also assessed. Results show that when satellite visibility is poor (approximately 50% solution availability) the benefits of GLONASS are only seen with tight integration algorithms. For more benign environments, a loosely coupled GPS/GLONASS/INS system offers performance comparable to that of a tightly coupled GPS/INS system, but with reduced complexity and development time.

A MEMS Condenser Microphone-Based Intracochlear Acoustic Receiver.

PubMed

Pfiffner, Flurin; Prochazka, Lukas; Peus, Dominik; Dobrev, Ivo; Dalbert, Adrian; Sim, Jae Hoon; Kesterke, Rahel; Walraevens, Joris; Harris, Francesca; Roosli, Christof; Obrist, Dominik; Huber, Alexander

2017-10-01

Intracochlear sound pressure (ICSP) measurements are limited by the small dimensions of the human inner ear and the requirements imposed by the liquid medium. A robust intracochlear acoustic receiver (ICAR) for repeated use with a simple data acquisition system that provides the required high sensitivity and small dimensions does not yet exist. The work described in this report aims to fill this gap and presents a new microelectromechanical systems (MEMS) condenser microphone (CMIC)-based ICAR concept suitable for ICSP measurements in human temporal bones. The ICAR head consisted of a passive protective diaphragm (PD) sealing the MEMS CMIC against the liquid medium, enabling insertion into the inner ear. The components of the MEMS CMIC-based ICAR were expressed by a lumped element model (LEM) and compared to the performance of successfully fabricated ICARs. Good agreement was achieved between the LEM and the measurements with different sizes of the PD. The ICSP measurements in a human cadaver temporal bone yielded data in agreement with the literature. Our results confirm that the presented MEMS CMIC-based ICAR is a promising technology for measuring ICSP in human temporal bones in the audible frequency range. A sensor for evaluation of the biomechanical hearing process by quantification of ICSP is presented. The concept has potential as an acoustic receiver in totally implantable cochlear implants.

A digital output piezoelectric accelerometer using a Pb(Zr, Ti)O3 thin film array electrically connected in series

NASA Astrophysics Data System (ADS)

Kobayashi, T.; Okada, H.; Masuda, T.; Maeda, R.; Itoh, T.

2010-10-01

A digital output piezoelectric accelerometer is proposed to realize an ultra-low power consumption wireless sensor node. The accelerometer has patterned piezoelectric thin films (piezoelectric plates) electrically connected in series accompanied by CMOS switches at the end of some of the piezoelectric plates. The connected piezoelectric plates amplify the output voltage without the use of amplifiers. The CMOS switches turn on when the output voltage of the piezoelectric plates is higher than the CMOS threshold voltage. The piezoelectric accelerometer converts the acceleration into a number of on-state CMOS switches, which can be called the digital output. The proposed digital output piezoelectric accelerometer, using Pb(Zr, Ti)O3 (PZT) thin films as the piezoelectric material, was fabricated through a microelectromechanical system (MEMS) microfabrication process. The output voltage was found to be amplified by the number of connected piezoelectric plates. The DC output voltage obtained by using an AC to DC conversion circuit is proportional to the number of connections. The results show the potential for realizing the proposed digital output piezoelectric accelerometer.

FOREWORD: Focus on Novel Nanoelectromechanical 3D Structures: Fabrication and Properties Focus on Novel Nanoelectromechanical 3D Structures: Fabrication and Properties

NASA Astrophysics Data System (ADS)

Yamada, Shooji; Yamaguchi, Hiroshi; Ishihara, Sunao

2009-06-01

Microelectromechanical systems (MEMS) are widely used small electromechanical systems made of micrometre-sized components. Presently, we are witnessing a transition from MEMS to nanoelectromechanical systems (NEMS), which comprise devices integrating electrical and mechanical functionality on the nanoscale and offer new exciting applications. Similarly to MEMS, NEMS typically include a central transistor-like nanoelectronic unit for data processing, as well as mechanical actuators, pumps, and motors; and they may combine with physical, biological and chemical sensors. In the transition from MEMS to NEMS, component sizes need to be reduced. Therefore, many fabrication methods previously developed for MEMS are unsuitable for the production of high-precision NEMS components. The key challenge in NEMS is therefore the development of new methods for routine and reproducible nanofabrication. Two complementary types of method for NEMS fabrication are available: 'top-down' and 'bottom-up'. The top-down approach uses traditional lithography technologies, whereas bottom-up techniques include molecular self-organization, self-assembly and nanodeposition. The NT2008 conference, held at Ishikawa High-Tech Conference Center, Ishikawa, Japan, between 23-25 October 2008, focused on novel NEMS fabricated from new materials and on process technologies. The topics included compound semiconductors, small mechanical structures, nanostructures for micro-fluid and bio-sensors, bio-hybrid micro-machines, as well as their design and simulation. This focus issue compiles seven articles selected from 13 submitted manuscripts. The articles by Prinz et al and Kehrbusch et al introduce the frontiers of the top-down production of various operational NEMS devices, and Kometani et al present an example of the bottom-up approach, namely ion-beam induced deposition of MEMS and NEMS. The remaining articles report novel technologies for biological sensors. Taira et al have used manganese nanoparticles to improve the chemical analysis of biological samples by laser desorption/ionization mass spectrometry. Matsumoto et al have prepared sugar microarrays via click chemistry and have applied this to the detection and characterization of proteins. Yoshimura et al have expanded the single-nucleotide polymorphism typing method to differentiate genes from various food crops, such as indica and japonica rice. Finally, Takashi et al have designed a nanoparticle-based strip sensor, which can be used for rapid evaluation of the psychological condition of animals and humans. We hope that this focus issue will help readers to understand, from a materials science viewpoint, different aspects of frontier research into NEMS.

Integrated System Technologies for Modular Trapped Ion Quantum Information Processing

NASA Astrophysics Data System (ADS)

Crain, Stephen G.

Although trapped ion technology is well-suited for quantum information science, scalability of the system remains one of the main challenges. One of the challenges associated with scaling the ion trap quantum computer is the ability to individually manipulate the increasing number of qubits. Using micro-mirrors fabricated with micro-electromechanical systems (MEMS) technology, laser beams are focused on individual ions in a linear chain and steer the focal point in two dimensions. Multiple single qubit gates are demonstrated on trapped 171Yb+ qubits and the gate performance is characterized using quantum state tomography. The system features negligible crosstalk to neighboring ions (< 3e-4), and switching speeds comparable to typical single qubit gate times (< 2 mus). In a separate experiment, photons scattered from the 171Yb+ ion are coupled into an optical fiber with 63% efficiency using a high numerical aperture lens (0.6 NA). The coupled photons are directed to superconducting nanowire single photon detectors (SNSPD), which provide a higher detector efficiency (69%) compared to traditional photomultiplier tubes (35%). The total system photon collection efficiency is increased from 2.2% to 3.4%, which allows for fast state detection of the qubit. For a detection beam intensity of 11 mW/cm 2, the average detection time is 23.7 mus with 99.885(7)% detection fidelity. The technologies demonstrated in this thesis can be integrated to form a single quantum register with all of the necessary resources to perform local gates as well as high fidelity readout and provide a photon link to other systems.

Microsystems: from technologies to products

NASA Astrophysics Data System (ADS)

Ryser, Peter

2003-10-01

In this paper, we outline the process leading from technologies to successful products in the MEMS (Microelectromechanical Systems) and MST (Microsystems Technology) field. The development of new products involves a lot of factors, such as mature technologies, interdisciplinary team, identifying the right business potential and long term oriented investors. The paper summarizes a survey of different technologies and point out that packaging, test and calibration are still major shortcomings for the concerned industries.

On the measurement of stationary electric fields in air

NASA Technical Reports Server (NTRS)

Kirkham, H.

2002-01-01

Applications and measurement methods for field measurements are reviewed. Recent developments using optical technology are examined. The various methods are compared. It is concluded that the best general purpose instrument is the isolated cylindrical field mill, but MEMS technology could furnish better instruments in the future.

Design and optimization of stress centralized MEMS vector hydrophone with high sensitivity at low frequency

NASA Astrophysics Data System (ADS)

Zhang, Guojun; Ding, Junwen; Xu, Wei; Liu, Yuan; Wang, Renxin; Han, Janjun; Bai, Bing; Xue, Chenyang; Liu, Jun; Zhang, Wendong

2018-05-01

A micro hydrophone based on piezoresistive effect, "MEMS vector hydrophone" was developed for acoustic detection application. To improve the sensitivity of MEMS vector hydrophone at low frequency, we reported a stress centralized MEMS vector hydrophone (SCVH) mainly used in 20-500 Hz. Stress concentration area was actualized in sensitive unit of hydrophone by silicon micromachining technology. Then piezoresistors were placed in stress concentration area for better mechanical response, thereby obtaining higher sensitivity. Static analysis was done to compare the mechanical response of three different sensitive microstructure: SCVH, conventional micro-silicon four-beam vector hydrophone (CFVH) and Lollipop-shaped vector hydrophone (LVH) respectively. And fluid-structure interaction (FSI) was used to analyze the natural frequency of SCVH for ensuring the measurable bandwidth. Eventually, the calibration experiment in standing wave field was done to test the property of SCVH and verify the accuracy of simulation. The results show that the sensitivity of SCVH has nearly increased by 17.2 dB in contrast to CFVH and 7.6 dB in contrast to LVH during 20-500 Hz.

Automatic classification of singular elements for the electrostatic analysis of microelectromechanical systems

NASA Astrophysics Data System (ADS)

Su, Y.; Ong, E. T.; Lee, K. H.

2002-05-01

The past decade has seen an accelerated growth of technology in the field of microelectromechanical systems (MEMS). The development of MEMS products has generated the need for efficient analytical and simulation methods for minimizing the requirement for actual prototyping. The boundary element method is widely used in the electrostatic analysis for MEMS devices. However, singular elements are needed to accurately capture the behavior at singular regions, such as sharp corners and edges, where standard elements fail to give an accurate result. The manual classification of boundary elements based on their singularity conditions is an immensely laborious task, especially when the boundary element model is large. This process can be automated by querying the geometric model of the MEMS device for convex edges based on geometric information of the model. The associated nodes of the boundary elements on these edges can then be retrieved. The whole process is implemented in the MSC/PATRAN platform using the Patran Command Language (the source code is available as supplementary data in the electronic version of this journal issue).

A multi-conjugate adaptive optics testbed using two MEMS deformable mirrors

NASA Astrophysics Data System (ADS)

Andrews, Jonathan R.; Martinez, Ty; Teare, Scott W.; Restaino, Sergio R.; Wilcox, Christopher C.; Santiago, Freddie; Payne, Don M.

2011-03-01

Adaptive optics (AO) systems are well demonstrated in the literature with both laboratory and real-world systems being developed. Some of these systems have employed MEMS deformable mirrors as their active corrective element. More recent work in AO for astronomical applications has focused on providing correction in more than one conjugate plane. Additionally, horizontal path AO systems are exploring correction in multiple conjugate planes. This provides challenges for a laboratory system as the aberrations need to be generated and corrected in more than one plane in the optical system. Our work with compact AO systems employing MEMS technology in addition to liquid crystal spatial light modulator (SLM) driven aberration generators has been scaled up to a two conjugate plane testbed. Using two SLM based aberration generators and two separate wavefront sensors, the system can apply correction with two MEMS deformable mirrors. The challenges in such a system are to properly match non-identical components and weight the correction algorithm for correcting in two planes. This paper demonstrates preliminary results and analysis with this system with wavefront data and residual error measurements.

EDITORIAL: MEMS in biology and medicine MEMS in biology and medicine

NASA Astrophysics Data System (ADS)

Pruitt, Beth L.; Herr, Amy E.

2011-05-01

Stimulating—the first word that springs to mind regarding the emerging and expanding role of MEMS in biological inquiry. When invited to guest-edit this special issue on 'MEMS in biology and medicine' for JMM, we jumped at the opportunity. Partly owing to the breadth of the stimulating research in this nascent area and partly owing to the stimulating of biological function made possible with MEMS accessible length and time scales, we were eager to assemble manuscripts detailing some of the most cutting edge biological research being conducted around the globe. In addition to cutting edge engineering, this special issue features challenging biological questions addressed with innovative MEMS technologies. Topics span from Yetisen and colleagues' inquiry into quantifying pollen tube behaviour in response to pistil tissues [1] to Morimoto and colleagues' engineering efforts to produce monodisperse droplets capable of encapsulating single cells (without surface modification) [2]. Questions are bold, including a means to achieve therapeutically-relevant scaling for enrichment of leukocytes from blood (Inglis et al [3]), assessing the dependence of Escherichia coli biofilm formation on bacterial signalling (Meyer et al [4]), and elucidation of adhesion dynamics of circulating tumour cells (Cheung et al [5]) among others. Technologies are diverse, including microfabricated magnetic actuators (Lee et al [6]), stimuli-responsive polymer nanocomposites (Hess et al [7]), and SU-8 electrothermal microgrippers (Chu et al [8]) to name but a few. Contributing authors do indeed span a large swathe of the globe, with contributions from Australia, Italy, China, Canada, Denmark, Japan, the USA and numerous other locations. Collaboration finds a home here—with researchers from macromolecular science and electrical engineering collaborating with the Veterans Affairs Medical Center or neurosurgery researchers working with biological and electrical engineers. The questions posed by this generation of MEMS researchers encapsulate the mission of JMM to 'cover all aspects of microelectromechanical systems, devices and structures as well as micromechanics, microengineering and microfabrication' as the physics and chemical processes under study match the scales of the MEMS technologies now possible. As evidenced by the articles assembled in this issue, the combined maturation of both our biological model systems and our tools is driving a new paradigm in the formulation of biological hypotheses. The intersection of MEMS with cell biology is evidenced in reviews of both methods for applying microscale forces in biological environments by Zheng and Zhang [9] as well as the manipulation of biology through mechanical interactions by Rajagopalan and Saif [10]. Additionally, the potential for microfluidic platforms to miniaturize and improve for a diverse set of biological measurements and assays for medical diagnostics is further reviewed by Tentori and Herr [11]. We hope that you find, as we do, this special issue to be 'essential reading for all MEMS researchers' and perhaps even of technical interest to your life sciences colleagues. References [1] Yetisen A K et al 2011 J. Micromech. Microeng. 21 054018 [2] Morimoto Y et al 2011 J. Micromech. Microeng. 21 054031 [3] Inglis D W et al 2011 J. Micromech. Microeng. 21 054024 [4] Meyer M T et al 2011 J. Micromech. Microeng. 21 054023 [5] Cheung L S-L et al 2011 J. Micromech. Microeng. 21 054033 [6] Lee S A et al 2011 J. Micromech. Microeng. 21 054006 [7] Hess A E et al 2011 J. Micromech. Microeng. 21 054009 [8] Chu J et al 2011 J. Micromech. Microeng. 21 054030 [9] Zheng X R and Zhang X 2011 J. Micromech. Microeng. 21 054003 [10] Rajagopalan J and Saif M T A 2011 J. Micromech. Microeng. 21 054002 [11] Tentori A M and Herr A E 2011 J. Micromech. Microeng. 21 054001

Materials challenges for repeatable RF wireless device reconfiguration with microfluidic channels

NASA Astrophysics Data System (ADS)

Griffin, Anthony S.; Sottos, Nancy R.; White, Scott R.

2018-03-01

Recently, adaptive wireless devices have utilized displacement of EGaIn within microchannels as an electrical switching mechanism to enable reconfigurable electronics. Device reconfiguration using EGaIn in microchannels overcomes many challenges encountered by more traditional reconfiguration mechanisms such as diodes and microelectromechanical systems (MEMS). Reconfiguration using EGaIn is severely limited by undesired permanent shorting due to retention of the liquid in microchannels caused by wetting and rapid oxide skin formation. Here, we investigate the conditions which prevent repeatable electrical switching using EGaIn in microchannels. Initial contact angle tests of EGaIn on epoxy surfaces demonstrate the wettability of EGaIn on flat surfaces. SEM cross-sections of microchannels reveal adhesion of EGaIn residue to channel walls. Micro-computed tomography (microCT) scans of provide volumetric measurements of EGaIn remaining inside channels after flow cycling. Non-wetting coatings are proposed as materials based strategy to overcome these issues in future work.

Method for forming permanent magnets with different polarities for use in microelectromechanical devices

DOEpatents

Roesler, Alexander W [Tijeras, NM; Christenson, Todd R [Albuquerque, NM

2007-04-24

Methods are provided for forming a plurality of permanent magnets with two different north-south magnetic pole alignments for use in microelectromechanical (MEM) devices. These methods are based on initially magnetizing the permanent magnets all in the same direction, and then utilizing a combination of heating and a magnetic field to switch the polarity of a portion of the permanent magnets while not switching the remaining permanent magnets. The permanent magnets, in some instances, can all have the same rare-earth composition (e.g. NdFeB) or can be formed of two different rare-earth materials (e.g. NdFeB and SmCo). The methods can be used to form a plurality of permanent magnets side-by-side on or within a substrate with an alternating polarity, or to form a two-dimensional array of permanent magnets in which the polarity of every other row of the array is alternated.

Enantiomeric switching of chiral metamaterial for terahertz polarization modulation employing vertically deformable MEMS spirals

NASA Astrophysics Data System (ADS)

Kan, Tetsuo; Isozaki, Akihiro; Kanda, Natsuki; Nemoto, Natsuki; Konishi, Kuniaki; Takahashi, Hidetoshi; Kuwata-Gonokami, Makoto; Matsumoto, Kiyoshi; Shimoyama, Isao

2015-10-01

Active modulation of the polarization states of terahertz light is indispensable for polarization-sensitive spectroscopy, having important applications such as non-contact Hall measurements, vibrational circular dichroism measurements and anisotropy imaging. In the terahertz region, the lack of a polarization modulator similar to a photoelastic modulator in the visible range hampers expansion of such spectroscopy. A terahertz chiral metamaterial has a huge optical activity unavailable in nature; nevertheless, its modulation is still challenging. Here we demonstrate a handedness-switchable chiral metamaterial for polarization modulation employing vertically deformable Micro Electro Mechanical Systems. Vertical deformation of a planar spiral by a pneumatic force creates a three-dimensional spiral. Enantiomeric switching is realized by selecting the deformation direction, where the polarity of the optical activity is altered while maintaining the spectral shape. A polarization rotation as high as 28° is experimentally observed, thus providing a practical and compact polarization modulator for the terahertz range.

Enantiomeric switching of chiral metamaterial for terahertz polarization modulation employing vertically deformable MEMS spirals.

PubMed

Kan, Tetsuo; Isozaki, Akihiro; Kanda, Natsuki; Nemoto, Natsuki; Konishi, Kuniaki; Takahashi, Hidetoshi; Kuwata-Gonokami, Makoto; Matsumoto, Kiyoshi; Shimoyama, Isao

2015-10-01

Active modulation of the polarization states of terahertz light is indispensable for polarization-sensitive spectroscopy, having important applications such as non-contact Hall measurements, vibrational circular dichroism measurements and anisotropy imaging. In the terahertz region, the lack of a polarization modulator similar to a photoelastic modulator in the visible range hampers expansion of such spectroscopy. A terahertz chiral metamaterial has a huge optical activity unavailable in nature; nevertheless, its modulation is still challenging. Here we demonstrate a handedness-switchable chiral metamaterial for polarization modulation employing vertically deformable Micro Electro Mechanical Systems. Vertical deformation of a planar spiral by a pneumatic force creates a three-dimensional spiral. Enantiomeric switching is realized by selecting the deformation direction, where the polarity of the optical activity is altered while maintaining the spectral shape. A polarization rotation as high as 28° is experimentally observed, thus providing a practical and compact polarization modulator for the terahertz range.

Micro hot embossing for high-aspect-ratio structure with materials flow enhancement by polymer sheet

NASA Astrophysics Data System (ADS)

Murakoshi, Yoichi; Shan, Xue-Chuan; Sano, Toshio; Takahashi, Masaharu; Maeda, Ryutaro

2004-04-01

Nano imprinting or Nano embossing process have been introduced to fabricate semiconductor, optical device and Micro Electro Mechanical Systems (MEMS) and the Nano Electro Mechanical Systems (NEMS) to reduce the fabrication cost. In our previous paper, micro hot embossing of Polycarbonate (PC) and Polyetheretherketone (PEEK) for optical switch with 8x8 mirrors was reported. The PC and PEEK sheets were embossed at elevated temperature with an embossing machine designed for the MEMS. In the application, the mirrors on the optical switch had some defects, such as slump, sticking and step at side of the mirror, due to embossing process and process conditions. These defects are attributed to the poor materials flow of plastics into the e Ni mold cavity of complicate shape with different aspect ratio. Therefore, the micro hot embossing is optimized in this paper with PTFE sheet to enhance the materials flow. In this paper, the PC and the PEEK sheets, thickness of 300um, are embossed at elevated temperature with the hot embossing machine with a Nickel mold. To control material flow of the PC or the PEEK sheets, Polytetrafluoroethylene (PTFE) sheet, the thickness of 100um, is placed on the PC or the PEEK sheets at elevated temperature. Mirror shape was transferred with better fidelity on the PC and PEEK sheet, and the thickness of cantilever became thinner than previous embossed structure without the PTFE. Especially, the mirror height and the thickness of cantilever on the PC have been improved at lower embossing temperature.

Study on film resistivity of Energy Conversion Components for MEMS Initiating Explosive Device

NASA Astrophysics Data System (ADS)

Ren, Wei; Zhang, Bin; Zhao, Yulong; Chu, Enyi; Yin, Ming; Li, Hui; Wang, Kexuan

2018-03-01

Resistivity of Plane-film Energy Conversion Components is a key parameter to influence its resistance and explosive performance, and also it has important relations with the preparation of thin film technology, scale, structure and etc. In order to improve the design of Energy Conversion Components for MEMS Initiating Explosive Device, and reduce the design deviation of Energy Conversion Components in microscale, guarantee the design resistance and ignition performance of MEMS Initiating Explosive Device, this paper theoretically analyzed the influence factors of film resistivity in microscale, through the preparation of Al film and Ni-Cr film at different thickness with micro/nano, then obtain the film resistivity parameter of the typical metal under different thickness, and reveals the effect rule of the scale to the resistivity in microscale, at the same time we obtain the corresponding inflection point data.

Differential wide temperature range CMOS interface circuit for capacitive MEMS pressure sensors.

PubMed

Wang, Yucai; Chodavarapu, Vamsy P

2015-02-12

We describe a Complementary Metal-Oxide Semiconductor (CMOS) differential interface circuit for capacitive Micro-Electro-Mechanical Systems (MEMS) pressure sensors that is functional over a wide temperature range between -55 °C and 225 °C. The circuit is implemented using IBM 0.13 μm CMOS technology with 2.5 V power supply. A constant-gm biasing technique is used to mitigate performance degradation at high temperatures. The circuit offers the flexibility to interface with MEMS sensors with a wide range of the steady-state capacitance values from 0.5 pF to 10 pF. Simulation results show that the circuitry has excellent linearity and stability over the wide temperature range. Experimental results confirm that the temperature effects on the circuitry are small, with an overall linearity error around 2%.

Differential Wide Temperature Range CMOS Interface Circuit for Capacitive MEMS Pressure Sensors

PubMed Central

Wang, Yucai; Chodavarapu, Vamsy P.

2015-01-01

We describe a Complementary Metal-Oxide Semiconductor (CMOS) differential interface circuit for capacitive Micro-Electro-Mechanical Systems (MEMS) pressure sensors that is functional over a wide temperature range between −55 °C and 225 °C. The circuit is implemented using IBM 0.13 μm CMOS technology with 2.5 V power supply. A constant-gm biasing technique is used to mitigate performance degradation at high temperatures. The circuit offers the flexibility to interface with MEMS sensors with a wide range of the steady-state capacitance values from 0.5 pF to 10 pF. Simulation results show that the circuitry has excellent linearity and stability over the wide temperature range. Experimental results confirm that the temperature effects on the circuitry are small, with an overall linearity error around 2%. PMID:25686312

Dynamic focus-tracking MEMS scanning micromirror with low actuation voltages for endoscopic imaging

PubMed Central

Strathman, Matthew; Liu, Yunbo; Li, Xingde; Lin, Lih Y.

2013-01-01

We demonstrate a 3-D scanning micromirror device that combines 2-D beam scanning with focus control in the same device using micro-electro-mechanical-systems (MEMS) technology. 2-D beam scanning is achieved with a biaxial gimbal structure and focus control is obtained with a deformable mirror membrane surface. The micromirror with 800 micrometer diameter is designed to be sufficiently compact and efficient so that it can be incorporated into an endoscopic imaging probe in the future. The design, fabrication and characterization of the device are described in this paper. Using the focus-tracking MEMS scanning mirror, we achieved an optical scanning range of >16 degrees with <40 V actuation voltage at resonance and a tunable focal length between infinity and 25 mm with <100V applied bias. PMID:24104304

Large-area multiplexed sensing using MEMS and fiber optics

NASA Astrophysics Data System (ADS)

Miller, Michael B.; Clark, Richard L., Jr.; Bell, Clifton R.; Russler, Patrick M.

2000-06-01

Micro-electro-mechanical (MEMS) technology offers the ability to implement local and independent sensing and actuation functions through the coordinated response of discrete micro-electro-mechanical 'basis function' elements. The small size of micromechanical components coupled with the ability to reduce costs using volume manufacturing techniques opens up significant potential not only in military applications such as flight and engine monitoring and control, but in autonomous vehicle control, smart munitions, airborne reconnaissance, LADAR, missile guidance, and even in intelligent transportation systems and automotive guidance applications. In this program, Luna Innovations is developing a flexible, programmable interface which can be integrated direction with different types of MEMS sensors, and then used to multiplex many sensors ona single optical fiber to provide a unique combination of functions that will allow larger quantities of sensory input with better resolution than ever before possible.

Structural design of high-performance capacitive accelerometers using parametric optimization with uncertainties

NASA Astrophysics Data System (ADS)

Teves, André da Costa; Lima, Cícero Ribeiro de; Passaro, Angelo; Silva, Emílio Carlos Nelli

2017-03-01

Electrostatic or capacitive accelerometers are among the highest volume microelectromechanical systems (MEMS) products nowadays. The design of such devices is a complex task, since they depend on many performance requirements, which are often conflicting. Therefore, optimization techniques are often used in the design stage of these MEMS devices. Because of problems with reliability, the technology of MEMS is not yet well established. Thus, in this work, size optimization is combined with the reliability-based design optimization (RBDO) method to improve the performance of accelerometers. To account for uncertainties in the dimensions and material properties of these devices, the first order reliability method is applied to calculate the probabilities involved in the RBDO formulation. Practical examples of bulk-type capacitive accelerometer designs are presented and discussed to evaluate the potential of the implemented RBDO solver.

MEMS-Based Micro Instruments for In-Situ Planetary Exploration

NASA Technical Reports Server (NTRS)

George, Thomas; Urgiles, Eduardo R; Toda, Risaku; Wilcox, Jaroslava Z.; Douglas, Susanne; Lee, C-S.; Son, Kyung-Ah; Miller, D.; Myung, N.; Madsen, L.;

Can mobile phones used in strong motion seismology?

NASA Astrophysics Data System (ADS)

D'Alessandro, Antonino; D'Anna, Giuseppe

2013-04-01

Micro Electro-Mechanical Systems (MEMS) accelerometers are electromechanical devices able to measure static or dynamic accelerations. In the 1990s MEMS accelerometers revolutionized the automotive-airbag system industry and are currently widely used in laptops, game controllers and mobile phones. Nowadays MEMS accelerometers seems provide adequate sensitivity, noise level and dynamic range to be applicable to earthquake strong motion acquisition. The current use of 3 axes MEMS accelerometers in mobile phone maybe provide a new means to easy increase the number of observations when a strong earthquake occurs. However, before utilize the signals recorded by a mobile phone equipped with a 3 axes MEMS accelerometer for any scientific porpoise, it is fundamental to verify that the signal collected provide reliable records of ground motion. For this reason we have investigated the suitability of the iPhone 5 mobile phone (one of the most popular mobile phone in the world) for strong motion acquisition. It is provided by several MEMS devise like a three-axis gyroscope, a three-axis electronic compass and a the LIS331DLH three-axis accelerometer. The LIS331DLH sensor is a low-cost high performance three axes linear accelerometer, with 16 bit digital output, produced by STMicroelectronics Inc. We have tested the LIS331DLH MEMS accelerometer using a vibrating table and the EpiSensor FBA ES-T as reference sensor. In our experiments the reference sensor was rigidly co-mounted with the LIS331DHL MEMS sensor on the vibrating table. We assessment the MEMS accelerometer in the frequency range 0.2-20 Hz, typical range of interesting in strong motion seismology and earthquake engineering. We generate both constant and damped sine waves with central frequency starting from 0.2 Hz until 20 Hz with step of 0.2 Hz. For each frequency analyzed we generate sine waves with mean amplitude 50, 100, 200, 400, 800 and 1600 mg0. For damped sine waves we generate waveforms with initial amplitude of 2 g0. Our tests show as, in the frequency and amplitude range analyzed (0.2-20 Hz, 10-2000 mg0), the LIS331DLH MEMS accelerometer have excellent frequency and phase response, comparable with that of some standard FBA accelerometer used in strong motion seismology. However, we found that the signal recorded by the LIS331DLH MEMS accelerometer slightly underestimates the real acceleration (of about 2.5%). This suggests that may be important to calibrate a MEMS sensor before using it in scientific applications. A drawback of the LIS331DLH MEMS accelerometer is its low sensitivity. This is an important limitation of all the low cost MEMS accelerometers; therefore nowadays they are desirable to use only in strong motion seismology. However, the rapid development of this technology will lead in the coming years to the development of high sensitivity and low noise digital MEMS sensors that may be replace the current seismic accelerometer used in seismology. Actually, the real main advantage of these sensors is their common use in the mobile phones.

Micro-Raman Analysis of Irradiated Diamond Films

NASA Technical Reports Server (NTRS)

Newton, Robert L.

2003-01-01

Owing to its unique and robust physical properties, diamond is a much sought after material for use in advanced technologies, even in Microelectromechanical Systems (MEMS). The volume and weight savings promised by MEMS-based devices are of particular interest to spaceflight applications. However, much basic materials science research remains to be completed in this field. Results of micro-Raman analysis of proton (10(exp 15) - 10(exp 17) H(+)/sq cm doses) irradiated chemical vapor deposited (CVD) films are presented and indicate that their microstructure is retained even after high radiation exposure.

Radio Relays Improve Wireless Products

NASA Technical Reports Server (NTRS)

2009-01-01

Signal Hill, California-based XCOM Wireless Inc. developed radio frequency micromachine (RF MEMS) relays with a Phase II Small Business Innovation Research (SBIR) contract through NASA?s Jet Propulsion Laboratory. In order to improve satellite communication systems, XCOM produced wireless RF MEMS relays and tunable capacitors that use metal-to-metal contact and have the potential to outperform most semiconductor technologies while using less power. These relays are used in high-frequency test equipment and instrumentation, where increased speed can mean significant cost savings. Applications now also include mainstream wireless applications and greatly improved tactical radios.

Scanning laser beam displays based on a 2D MEMS

NASA Astrophysics Data System (ADS)

Niesten, Maarten; Masood, Taha; Miller, Josh; Tauscher, Jason

2010-05-01

The combination of laser light sources and MEMS technology enables a range of display systems such as ultra small projectors for mobile devices, head-up displays for vehicles, wearable near-eye displays and projection systems for 3D imaging. Images are created by scanning red, green and blue lasers horizontally and vertically with a single two-dimensional MEMS. Due to the excellent beam quality of laser beams, the optical designs are efficient and compact. In addition, the laser illumination enables saturated display colors that are desirable for augmented reality applications where a virtual image is used. With this technology, the smallest projector engine for high volume manufacturing to date has been developed. This projector module has a height of 7 mm and a volume of 5 cc. The resolution of this projector is WVGA. No additional projection optics is required, resulting in an infinite focus depth. Unlike with micro-display projection displays, an increase in resolution will not lead to an increase in size or a decrease in efficiency. Therefore future projectors can be developed that combine a higher resolution in an even smaller and thinner form factor with increased efficiencies that will lead to lower power consumption.

Analysis of dual-frequency MEMS antenna using H-MRTD method

NASA Astrophysics Data System (ADS)

Yu, Wenge; Zhong, Xianxin; Chen, Yu; Wu, Zhengzhong

2004-10-01

For applying micro/nano technologies and Micro-Electro-Mechanical System (MEMS) technologies in the Radio Frequency (RF) field to manufacture miniature microstrip antennas. A novel MEMS dual-band patch antenna designed using slot-loaded and short-circuited size-reduction techniques is presented in this paper. By controlling the short-plane width, the two resonant frequencies, f10 and f30, can be significantly reduced and the frequency ratio (f30/f10) is tunable in the range 1.7~2.3. The Haar-Wavelet-Based multiresolution time domain (H-MRTD) with compactly supported scaling function for a full three-dimensional (3-D) wave to Yee's staggered cell is used for modeling and analyzing the antenna for the first time. Associated with practical model, an uniaxial perfectly matched layer (UPML) absorbing boundary conditions was developed, In addition , extending the mathematical formulae to an inhomogenous media. Numerical simulation results are compared with those using the conventional 3-D finite-difference time-domain (FDTD) method and measured. It has been demonstrated that, with this technique, space discretization with only a few cells per wavelength gives accurate results, leading to a reduction of both memory requirement and computation time.

MEMS product engineering: methodology and tools

NASA Astrophysics Data System (ADS)

Ortloff, Dirk; Popp, Jens; Schmidt, Thilo; Hahn, Kai; Mielke, Matthias; Brück, Rainer

2011-03-01

The development of MEMS comprises the structural design as well as the definition of an appropriate manufacturing process. Technology constraints have a considerable impact on the device design and vice-versa. Product design and technology development are therefore concurrent tasks. Based on a comprehensive methodology the authors introduce a software environment that links commercial design tools from both area into a common design flow. In this paper emphasis is put on automatic low threshold data acquisition. The intention is to collect and categorize development data for further developments with minimum overhead and minimum disturbance of established business processes. As a first step software tools that automatically extract data from spreadsheets or file-systems and put them in context with existing information are presented. The developments are currently carried out in a European research project.

Advanced adaptive optics technology development

NASA Astrophysics Data System (ADS)

Olivier, Scot S.

2002-02-01

The NSF Center for Adaptive Optics (CfAO) is supporting research on advanced adaptive optics technologies. CfAO research activities include development and characterization of micro-electro-mechanical systems (MEMS) deformable mirror (DM) technology, as well as development and characterization of high-resolution adaptive optics systems using liquid crystal (LC) spatial light modulator (SLM) technology. This paper presents an overview of the CfAO advanced adaptive optics technology development activities including current status and future plans.

Evaluation of Thermo-Mechanical Stability of COTS Dual-Axis MEMS Accelerometers for Space Applications

NASA Technical Reports Server (NTRS)

Sharma, Ashok K.; Teverovksy, Alexander; Day, John H. (Technical Monitor)

2000-01-01

Microelectromechanical systems in MEMS is one of the fastest growing technologies in microelectronics, and is of great interest for military and aerospace applications. Accelerometers are the earliest and most developed representatives of MEMS. First demonstrated in 1979, micromachined accelerometers were used in automobile industry for air bag crash- sensing applications since 1990. In 1999, N4EMS accelerometers were used in NASA-JPL Mars Microprobe. The most developed accelerometers for airbag crash- sensing are rated for a full range of +/- 50 G. The range of sensitivity for accelerometers required for military or aerospace applications is much larger, varying from 20,000 G (to measure acceleration during gun and ballistic munition launches), and to 10(exp -6) G, when used as guidance sensors (to measure attitude and position of a spacecraft). The presence of moving parts on the surface of chip is specific to MEMS, and particularly, to accelerometers. This characteristic brings new reliability issues to micromachined accelerometers, including cyclic fatigue cracking of polysilicon cantilevers and springs, mechanical stresses that are caused by packaging and contamination in the internal cavity of the package. Studies of fatigue cracks initiation and growth in polysilicon showed that the fatigue damage may influence MEMS device performance, and the presence of water vapor significantly enhances crack initiation and growth. Environmentally induced failures, particularly, failures due to thermal cycling and mechanical shock are considered as one of major reliability concerns in MEMS. These environmental conditions are also critical for space applications of the parts. For example, the Mars pathfinder mission had experienced 80 mechanical shock events during the pyrotechnic separation processes.

Variable Emissivity Through MEMS Technology

NASA Technical Reports Server (NTRS)

Darrin, Ann Garrison; Osiander, Robert; Champion, John; Swanson, Ted; Douglas, Donya; Grob, Lisa M.; Powers, Edward I. (Technical Monitor)

2000-01-01

This paper discusses a new technology for variable emissivity (vari-e) radiator surfaces, which has significant advantages over traditional radiators and promises an alternative design technique for future spacecraft thermal control systems. All spacecraft rely on radiative surfaces to dissipate waste heat. These radiators have special coatings, typically with a low solar absorptivity and a high infrared-red emissivity, that are intended to optimize performance under the expected heat load and thermal sink environment. The dynamics of the heat loads and thermal environment make it a challenge to properly size the radiator and often require some means of regulating the heat rejection rate of the radiators in order to achieve proper thermal balance. Specialized thermal control coatings, which can passively or actively adjust their emissivity offer an attractive solution to these design challenges. Such systems would allow intelligent control of the rate of heat loss from a radiator in response to heat load and thermal environmental variations. Intelligent thermal control through variable emissivity systems is well suited for nano and pico spacecraft applications where large thermal fluctuations are expected due to the small thermal mass and limited electric resources. Presently there are three different types of vari-e technologies under development: Micro ElectroMechanical Systems (MEMS) louvers, Electrochromic devices, and Electrophoretic devices. This paper will describe several prototypes of micromachined (MEMS) louvers and experimental results for the emissivity variations measured on theses prototypes. It will further discuss possible actuation mechanisms and space reliability aspects for different designs. Finally, for comparison parametric evaluations of the thermal performances of the new vari-e technology and standard thermal control systems are presented in this paper.

Array Phase Shifters: Theory and Technology

NASA Technical Reports Server (NTRS)

Romanofsky, Robert R.

2007-01-01

While there are a myriad of applications for microwave phase shifters in instrumentation and metrology, power combining, amplifier linearization, and so on, the most prevalent use is in scanning phased-array antennas. And while this market continues to be dominated by military radar and tracking platforms, many commercial applications have emerged in the past decade or so. These new and potential applications span low-Earth-orbit (LEO) communications satellite constellations and collision warning radar, an aspect of the Intelligent Vehicle Highway System or Automated Highway System. In any case, the phase shifters represent a considerable portion of the overall antenna cost, with some estimates approaching 40 percent for receive arrays. Ferrite phase shifters continue to be the workhorse in military-phased arrays, and while there have been advances in thin film ferrite devices, the review of this device technology in the previous edition of this book is still highly relevant. This chapter will focus on three types of phase shifters that have matured in the past decade: GaAs MESFET monolithic microwave integrated circuit (MMIC), micro-electromechanical systems (MEMS), and thin film ferroelectric-based devices. A brief review of some novel devices including thin film ferrite phase shifters and superconducting switches for phase shifter applications will be provided. Finally, the effects of modulo 2 phase shift limitations, phase errors, and transient response on bit error rate degradation will be considered.

Heat convection in a micro impinging jet system

NASA Astrophysics Data System (ADS)

Mai, John Dzung Hoang

2000-10-01

This thesis covers the development of an efficient micro impinging jet heat exchanger, using MEMS technology, to provide localized cooling for present and next generation microelectronic computer chips. Before designing an efficient localized heat exchanger, it is necessary to investigate fluid dynamics and heat transfer in the micro scale. MEMS technology has been used in this project because it is the only tool currently available that can provide a large array of batch-fabricated, micro-scale nozzles for localized cooling. Our investigation of potential MEMS heat exchanger designs begins with experiments that measure the pressure drops and temperature changes in a micro scale tubing system that will be necessary to carry fluid to the impingement point. Our basic MEMS model is a freestanding micro channel with integrated temperature microsensors. The temperature distribution along the channel in a vacuum is measured. The measured flow rates are compared with an analytical model developed for capillary flow that accounts for 2-D, slip and compressibility effects. The work is focused on obtaining correlations in the form of the Nussult number, the Reynolds number and a H/d geometric factor. A set of single MEMS nozzles have been designed to test heat transfer effectiveness as a function of nozzle diameter, ranging from 1.0 mm to 250 um. In addition, nozzle and slot array MEMS devices have been fabricated. In order to obtain quantitative measurements from these micron scale devices, a series of target temperature sensor chips were custom made and characterized for these experiments. The heat transfer characteristics of various MEMS nozzle configurations operating at various steady inlet pressures, at different heights above the heated substrate, have been characterized. These steady results showed that the average heat transfer coefficient, averaged over a 1 cm2 test area, was usually less than 0.035 W/cm 2K for any situation. However, the local heat transfer coefficient, as measured by a single 4mum x 4mum temperature sensor, was as high as 0.5 W/cm2K. Using a mechanical valve and piezo actuator to perturb the flow at frequencies from 10 Hz to 1 kHz, we identify that enhanced heat transfer can occur in an unsteady forced jet. The functional dependence of the enhanced heat transfer on the mean jet speed, perturbation level and perturbing frequency has been established. The expected trend that increased heat transfer at higher values of St number was noticed. In addition the effect of a confined and free jet geometry on an unsteady flow was observed.

An investigation into graphene exfoliation and potential graphene application in MEMS devices

NASA Astrophysics Data System (ADS)

Fercana, George; Kletetschka, Gunther; Mikula, Vilem; Li, Mary

2011-02-01

The design of microelectromecanical systems (MEMS) and micro-opto-electromechanical systems (MOEMS) are often materials-limited with respect to the efficiency and capability of the material. Graphene, a one atom thick honeycomb lattice of carbon, is a highly desired material for MEMS applications. Relevant properties of graphene include the material's optical transparency, mechanical strength, energy efficiency, and electrical and thermal conductivity due to its electron mobility. Aforementioned properties make graphene a strong candidate to supplant existing transparent electrode technology and replace the conventionally used material, indium-tin oxide. In this paper we present preliminary results on work toward integration of graphene with MEMS structures. We are studying mechanical exfoliation of highly ordered pyrolytic graphite (HOPG) crystals by repeatedly applying and separating adhesive materials from the HOPG surface. The resulting graphene sheets are then transferred to silicon oxide substrate using the previously applied adhesive material. We explored different adhesive options, particularly the use of Kapton tape, to improve the yield of graphene isolation along with chemical cross-linking agents which operate on a mechanism of photoinsertion of disassociated nitrene groups. These perfluorophenyl nitrenes participate in C=C addition reactions with graphene monolayers creating a covalent binding between the substrate and graphene. We are focusing on maximizing the size of isolated graphene sheets and comparing to conventional exfoliation. Preliminary results allow isolation of few layer graphene (FLG) sheets (n<3) of approximately 10μm x 44μm. Photolithography could possibly be utilized to tailor designs for microshutter technology to be used in future deep space telescopes.

MEMS-based thermally-actuated image stabilizer for cellular phone camera

NASA Astrophysics Data System (ADS)

Lin, Chun-Ying; Chiou, Jin-Chern

2012-11-01

This work develops an image stabilizer (IS) that is fabricated using micro-electro-mechanical system (MEMS) technology and is designed to counteract the vibrations when human using cellular phone cameras. The proposed IS has dimensions of 8.8 × 8.8 × 0.3 mm3 and is strong enough to suspend an image sensor. The processes that is utilized to fabricate the IS includes inductive coupled plasma (ICP) processes, reactive ion etching (RIE) processes and the flip-chip bonding method. The IS is designed to enable the electrical signals from the suspended image sensor to be successfully emitted out using signal output beams, and the maximum actuating distance of the stage exceeds 24.835 µm when the driving current is 155 mA. Depending on integration of MEMS device and designed controller, the proposed IS can decrease the hand tremor by 72.5%.

MEMS device for mass market gas and chemical sensors

NASA Astrophysics Data System (ADS)

Kinkade, Brian R.; Daly, James T.; Johnson, Edward A.

2000-08-01

Gas and chemical sensors are used in many applications. Industrial health and safety monitors allow companies to meet OSHA requirements by detecting harmful levels of toxic or combustible gases. Vehicle emissions are tested during annual inspections. Blood alcohol breathalizers are used by law enforcement. Refrigerant leak detection ensures that the Earth's ozone layer is not being compromised. Industrial combustion emissions are also monitored to minimize pollution. Heating and ventilation systems watch for high levels of carbon dioxide (CO2) to trigger an increase in fresh air exchange. Carbon monoxide detectors are used in homes to prevent poisoning from poor combustion ventilation. Anesthesia gases are monitored during a patients operation. The current economic reality is that two groups of gas sensor technologies are competing in two distinct existing market segments - affordable (less reliable) chemical reaction sensors for consumer markets and reliable (expensive) infrared (IR) spectroscopic sensors for industrial, laboratory, and medical instrumentation markets. Presently high volume mass-market applications are limited to CO detectros and on-board automotive emissions sensors. Due to reliability problems with electrochemical sensor-based CO detectors there is a hesitancy to apply these sensors in other high volume applications. Applications such as: natural gas leak detection, non-invasive blood glucose monitoring, home indoor air quality, personal/portable air quality monitors, home fire/burnt cooking detector, and home food spoilage detectors need a sensor that is a small, efficient, accurate, sensitive, reliable, and inexpensive. Connecting an array of these next generation gas sensors to wireless networks that are starting to proliferate today creates many other applications. Asthmatics could preview the air quality of their destinations as they venture out into the day. HVAC systems could determine if fresh air intake was actually better than the air in the house. Internet grocery delivery services could check for spoiled foods in their clients' refrigerators. City emissions regulators could monitor the various emissions sources throughout the area from their desk to predict how many pollution vouchers they will need to trade in the next week. We describe a new component architecture for mass-market sensors based on silicon microelectromechanical systems (MEMS) technology. MEMS are micrometer-scale devices that can be fabricated as discrete devices or large arrays, using the technology of integrated circuit manufacturing. These new photonic bandgap and MEMS fabricataion technologies will simplify the component technology to provide high-quality gas and chemical sensors at consumer prices.

Large-area low-temperature ultrananocrystaline diamond (UNCD) films and integration with CMOS devices for monolithically integrated diamond MEMD/NEMS-CMOS systems.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sumant, A.V.; Auciello, O.; Yuan, H.-C

2009-05-01

Because of exceptional mechanical, chemical, and tribological properties, diamond has a great potential to be used as a material for the development of high-performance MEMS and NEMS such as resonators and switches compatible with harsh environments, which involve mechanical motion and intermittent contact. Integration of such MEMS/NEMS devices with complementary metal oxide semiconductor (CMOS) microelectronics will provide a unique platform for CMOS-driven commercial MEMS/NEMS. The main hurdle to achieve diamond-CMOS integration is the relatively high substrate temperatures (600-800 C) required for depositing conventional diamond thin films, which are well above the CMOS operating thermal budget (400 C). Additionally, a materialsmore » integration strategy has to be developed to enable diamond-CMOS integration. Ultrananocrystalline diamond (UNCD), a novel material developed in thin film form at Argonne, is currently the only microwave plasma chemical vapor deposition (MPCVD) grown diamond film that can be grown at 400 C, and still retain exceptional mechanical, chemical, and tribological properties comparable to that of single crystal diamond. We have developed a process based on MPCVD to synthesize UNCD films on up to 200 mm in diameter CMOS wafers, which will open new avenues for the fabrication of monolithically integrated CMOS-driven MEMS/NEMS based on UNCD. UNCD films were grown successfully on individual Si-based CMOS chips and on 200 mm CMOS wafers at 400 C in a MPCVD system, using Ar-rich/CH4 gas mixture. The CMOS devices on the wafers were characterized before and after UNCD deposition. All devices were performing to specifications with very small degradation after UNCD deposition and processing. A threshold voltage degradation in the range of 0.08-0.44V and transconductance degradation in the range of 1.5-9% were observed.« less

Advanced materials and techniques for fibre-optic sensing

NASA Astrophysics Data System (ADS)

Henderson, Philip J.

2014-06-01

Fibre-optic monitoring systems came of age in about 1999 upon the emergence of the world's first significant commercialising company - a spin-out from the UK's collaborative MAST project. By using embedded fibre-optic technology, the MAST project successfully measured transient strain within high-performance composite yacht masts. Since then, applications have extended from smart composites into civil engineering, energy, military, aerospace, medicine and other sectors. Fibre-optic sensors come in various forms, and may be subject to embedment, retrofitting, and remote interrogation. The unique challenges presented by each implementation require careful scrutiny before widespread adoption can take place. Accordingly, various aspects of design and reliability are discussed spanning a range of representative technologies that include resonant microsilicon structures, MEMS, Bragg gratings, advanced forms of spectroscopy, and modern trends in nanotechnology. Keywords: Fibre-optic sensors, fibre Bragg gratings, MEMS, MOEMS, nanotechnology, plasmon.

Simulation of Strain Induced Pseudomagnetic Fields in Graphene Suspended on MEMS Chevron Actuators

NASA Astrophysics Data System (ADS)

Vutukuru, Mounika; Christopher, Jason; Bishop, David; Swan, Anna

Graphene has been shown to withstand remarkable levels of mechanical strain an order of magnitude larger than bulk crystalline materials. This exceptional stretchability of graphene allows for the direct tuning of fundamental material properties, as well as for the investigation of novel physics such as generation of strain induced pseudomagnetic fields. However, current methods for strain such as polymer elongation or pressurized wells do not integrate well into devices. We propose microelectromechanical (MEMS) Chevron actuators as a reliable platform for applying strain to graphene. In addition to their advantageous controllable output force, low input power and ease of integration into existing technologies, MEMS allow for different strain orientations to optimize pseudomagnetic field generation in graphene. Here, we model nonuniform strain in suspended graphene on Chevron actuators using COMSOL Multiphysics. By simulating the deformation of the graphene geometry under the device actuation, we explore the pseudomagnetic field map induced by numerically calculating the components of the strain tensor. Our models provide the theoretical framework with which experimental analysis is compared, and optimize our MEMS designs for further exploration of novel physics in graphene. The authors would like to thank NSF DMR 1411008 for their support on this project.

A flexible Li-ion battery with design towards electrodes electrical insulation

NASA Astrophysics Data System (ADS)

Vieira, E. M. F.; Ribeiro, J. F.; Sousa, R.; Correia, J. H.; Goncalves, L. M.

2016-08-01

The application of micro electromechanical systems (MEMS) technology in several consumer electronics leads to the development of micro/nano power sources with high power and MEMS integration possibility. This work presents the fabrication of a flexible solid-state Li-ion battery (LIB) (~2.1 μm thick) with a design towards electrodes electrical insulation, using conventional, low cost and compatible MEMS fabrication processes. Kapton® substrate provides flexibility to the battery. E-beam deposited 300 nm thick Ge anode was coupled with LiCoO2/LiPON (cathode/solid-state electrolyte) in a battery system. LiCoO2 and LiPON films were deposited by RF-sputtering with a power source of 120 W and 100 W, respectively. LiCoO2 film was annealed at 400 °C after deposition. The new design includes Si3N4 and LiPO thin-films, providing electrode electrical insulation and a battery chemical stability safeguard, respectively. Microstructure and battery performance were investigated by scanning electron microscopy, electric resistivity and electrochemical measurements (open circuit potential, charge/discharge cycles and electrochemical impedance spectroscopy). A rechargeable thin-film and lightweight flexible LIB using MEMS processing compatible materials and techniques is reported.

Design, modeling and simulation of MEMS-based silicon Microneedles

NASA Astrophysics Data System (ADS)

Amin, F.; Ahmed, S.

2013-06-01

The advancement in semiconductor process engineering and nano-scale fabrication technology has made it convenient to transport specific biological fluid into or out of human skin with minimum discomfort. Fluid transdermal delivery systems such as Microneedle arrays are one such emerging and exciting Micro-Electro Mechanical System (MEMS) application which could lead to a total painless fluid delivery into skin with controllability and desirable yield. In this study, we aimed to revisit the problem with modeling, design and simulations carried out for MEMS based silicon hollow out of plane microneedle arrays for biomedical applications particularly for transdermal drug delivery. An approximate 200 μm length of microneedle with 40 μm diameter of lumen has been successfully shown formed by isotropic and anisotropic etching techniques using MEMS Pro design tool. These microneedles are arranged in size of 2 × 4 matrix array with center to center spacing of 750 μm. Furthermore, comparisons for fluid flow characteristics through these microneedle channels have been modeled with and without the contribution of the gravitational forces using mathematical models derived from Bernoulli Equation. Physical Process simulations have also been performed on TCAD SILVACO to optimize the design of these microneedles aligned with the standard Si-Fabrication lines.

Application of Au-Sn eutectic bonding in hermetic radio-frequency microelectromechanical system wafer level packaging

NASA Astrophysics Data System (ADS)

Wang, Qian; Choa, Sung-Hoon; Kim, Woonbae; Hwang, Junsik; Ham, Sukjin; Moon, Changyoul

2006-03-01

Development of packaging is one of the critical issues toward realizing commercialization of radio-frequency-microelectromechanical system (RF-MEMS) devices. The RF-MEMS package should be designed to have small size, hermetic protection, good RF performance, and high reliability. In addition, packaging should be conducted at sufficiently low temperature. In this paper, a low-temperature hermetic wafer level packaging scheme for the RF-MEMS devices is presented. For hermetic sealing, Au-Sn eutectic bonding technology at temperatures below 300°C is used. Au-Sn multilayer metallization with a square loop of 70 µm in width is performed. The electrical feed-through is achieved by the vertical through-hole via filling with electroplated Cu. The size of the MEMS package is 1 mm × 1 mm × 700 µm. The shear strength and hermeticity of the package satisfies the requirements of MIL-STD-883F. Any organic gases or contamination are not observed inside the package. The total insertion loss for the packaging is 0.075 dB at 2 GHz. Furthermore, the robustness of the package is demonstrated by observing no performance degradation and physical damage of the package after several reliability tests.

EDITORIAL: The 6th International Workshop on Micro and Nanotechnologies for Power Generation and Energy Conversion Applications (PowerMEMS 2006)

NASA Astrophysics Data System (ADS)

Fréchette, Luc G.

2007-09-01

Energy is a sector of paramount importance over the coming decades if we are to ensure sustainable development that respects our environment. The research and development of novel approaches to convert available energy into usable forms using micro and nanotechnologies can contribute towards this goal and meet the growing need for power in small scale portable applications. The dominant power sources for handheld and other portable electronics are currently primary and rechargeable batteries. Their limited energy density and adverse effects on the environment upon disposal suggest that alternative approaches need to be explored. This special issue will showcase some of the leading work in this area, initially presented at PowerMEMS 2006, the 6th International Workshop on Micro and Nanotechnologies for Power Generation and Energy Conversion Applications. Power MEMS are defined as microsystems for electrical power generation and other energy conversion applications, including propulsion and cooling. The range of power MEMS technologies includes micro thermodynamic machines, such as microturbines, miniature internal combustion engines and micro-coolers; solid-state direct energy conversion, such as thermoelectric and photovoltaic microstructures; micro electrochemical devices, such as micro fuel cells and nanostructure batteries; vibration energy harvesting devices, such as piezoelectric, magnetic or electrostatic micro generators, as well as micro thrusters and rocket engines for propulsion. These can either be driven by scavenging thermal, mechanical or solar energy from the environment, or from a stored energy source, such as chemical fuel or radioactive material. The unique scope leads to unique challenges in the development of power MEMS, ranging from the integration of novel materials to the efficient small scale implementation of energy conversion principles. In this special issue, Mitcheson et al provide a comparative assessment of three inertial vibration energy harvesting approaches. Technologies and approaches for micro heat engines are shared, ranging from a complete microsystem for thermal energy harvesting (Cho et al) to core bearing and microturbomachinery technologies for rotating micro heat engines (Waits et al, Nakajima et al). Electrochemical microsystems are also presented, based on methanol as fuel (Morse et al), as well as novel micro and nanofabrication approaches (Chu et al). Fuel cell microsystems with integrated hydrogen generation approaches are also investigated by Peterson et al and Varady et al, illustrating the benefits and challenges of miniaturizing complete power sources. Finally, biological micro fuel cells that leverage the principles found in nature are presented, in contrast to chemical fuel cells (Chen et al, Morishima et al). We hope that this work will inspire others to pursue innovative research and development activities in the area of power MEMS, and consequently contribute to addressing our energy challenges for the 21st century.

MEMS sensor technologies for human centred applications in healthcare, physical activities, safety and environmental sensing: a review on research activities in Italy.

PubMed

Ciuti, Gastone; Ricotti, Leonardo; Menciassi, Arianna; Dario, Paolo

2015-03-17

Over the past few decades the increased level of public awareness concerning healthcare, physical activities, safety and environmental sensing has created an emerging need for smart sensor technologies and monitoring devices able to sense, classify, and provide feedbacks to users' health status and physical activities, as well as to evaluate environmental and safety conditions in a pervasive, accurate and reliable fashion. Monitoring and precisely quantifying users' physical activity with inertial measurement unit-based devices, for instance, has also proven to be important in health management of patients affected by chronic diseases, e.g., Parkinson's disease, many of which are becoming highly prevalent in Italy and in the Western world. This review paper will focus on MEMS sensor technologies developed in Italy in the last three years describing research achievements for healthcare and physical activity, safety and environmental sensing, in addition to smart systems integration. Innovative and smart integrated solutions for sensing devices, pursued and implemented in Italian research centres, will be highlighted, together with specific applications of such technologies. Finally, the paper will depict the future perspective of sensor technologies and corresponding exploitation opportunities, again with a specific focus on Italy.

Adaptive optics for high-contrast imaging of faint substellar companions

NASA Astrophysics Data System (ADS)

Morzinski, Katie M.

Direct imaging of faint objects around bright stars is challenging because the primary star's diffracted light can overwhelm low-mass companions. Nevertheless, advances in adaptive optics (AO) and high-contrast imaging have revealed the first pictures of extrasolar planets. In this dissertation I employ today's high-contrast AO techniques to image brown dwarfs around stars in the nearby Hyades cluster. Furthermore, I prepare for the next generation of high-contrast AO instrumentation, by qualifying MEMS deformable mirrors for wavefront control in the Gemini Planet Imager. In Part I, I present discovery of 3 new brown dwarfs and 36 low-mass stellar companions to 85 stars in the Hyades, imaged with AO at Keck and Lick Observatories. The "locally-optimized combination of images" (LOCI) image-diversity technique filters out the primary star to reveal faint companions. This survey is complete to the hydrogen-burning limit at separations beyond 20 AU. In the complete sample, multiplicity increases as primary star mass decreases. Additionally, the brown dwarfs are at wide >150 AU separations. Finding this preference for low binding-energy systems is an unexpected result, as the Hyades is 625 Myr old and dynamically relaxed. Future work will continue to explore this trend to understand the dynamical and star formation history of the Hyades. The brown dwarfs are near interesting transition regimes for low-mass objects; therefore, characterizing their atmospheres with spectrophotometry will serve as an important benchmark for our understanding of these cool objects. In Part II, I demonstrate micro-electro-mechanical systems (MEMS) deformable mirrors for high-order wavefront control in the Gemini Planet Imager (GPI). MEMS micromirrors have thousands of degrees of freedom and represent a significant cost efficiency over conventional glass deformable mirrors, making them ideal for high-contrast AO. In Chapter 7, I present experimental evidence that MEMS actuators function well and are stable and repeatable at the sub-nm level over the course of an hour. In Chapter 8, I prove MEMS ability to correct high-order Kolmogorov turbulence and maintain the high-contrast "dark hole" in the GPI woofer-tweeter architecture. Finally, in Chapter 9, I analyze MEMS performance on sky with Villages, a telescope testbed for MEMS technology, visible-light AO, and open-loop control. The MEMS remains repeatably flat and controllable over ˜4 years and ˜800 hours of operation. Open loop control of the hysteresis-free MEMS produces a diffraction-limited core in I-band, while internal static errors dominate the on-sky error budget. This work establishes MEMS deformable mirrors as excellent wavefront correctors for high-order AO. The MEMS in GPI will produce a deeper, broader dark hole, allowing for detection and characterization of directly-imaged planets in a fainter, wider search space.

Intelligent switches of integrated lightwave circuits with core telecommunication functions

NASA Astrophysics Data System (ADS)

Izhaky, Nahum; Duer, Reuven; Berns, Neil; Tal, Eran; Vinikman, Shirly; Schoenwald, Jeffrey S.; Shani, Yosi

2001-05-01

We present a brief overview of a promising switching technology based on Silica on Silicon thermo-optic integrated circuits. This is basically a 2D solid-state optical device capable of non-blocking switching operation. Except of its excellent performance (insertion loss<5dB, switching time<2ms...), the switch enables additional important build-in functionalities. It enables single-to- single channel switching and single-to-multiple channel multicasting/broadcasting. In addition, it has the capability of channel weighting and variable output power control (attenuation), for instance, to equalize signal levels and compensate for unbalanced different optical input powers, or to equalize unbalanced EDFA gain curve. We examine the market segments appropriate for the switch size and technology, followed by a discussion of the basic features of the technology. The discussion is focused on important requirements from the switch and the technology (e.g., insertion loss, power consumption, channel isolation, extinction ratio, switching time, and heat dissipation). The mechanical design is also considered. It must take into account integration of optical fiber, optical planar wafer, analog electronics and digital microprocessor controls, embedded software, and heating power dissipation. The Lynx Photon.8x8 switch is compared to competing technologies, in terms of typical market performance requirements.

PREFACE: MEM07: The 5th Annual Workshop on Mechanical and Electromagnetic Properties of Composite Superconductors (Princeton, NJ, USA, 21 24 August 2007)

NASA Astrophysics Data System (ADS)

Larbalestier, D. C.; Osamura, K.; Hampshire, D. P.

2008-05-01

MEM07 was the 5th international workshop concentrating on the mechanical and electrical properties of composite superconductors, which are the technological conductor forms from which practical superconducting devices are made. Such superconducting conductors respond to important challenges we currently face, especially those concerned with the proper management of the world's energy resources. Superconductivity provides a means to address the challenges in the generation, transmission and distribution, and use of energy. For energy generation, the ITER Fusion Tokomak (now underway in France) provides exciting new challenges for the whole superconductivity community, due to the enormous size and strong fields of the plasma confinement superconducting magnets that will form the largest and most powerful superconducting machine yet built. Significant attention was paid at MEM07 to the modeling, characterization, testing and validation of the high-amperage Nb3Sn cable-in-conduit conductors needed for ITER. As for electric energy industry uses, there was much discussion of both first generation (Bi,Pb)2Sr2Ca2Cu3Ox conductors and the rapidly emerging second generation coated conductors made from YBa2Cu37-x. High-performing, affordable conductors of these materials are vital for large capacity transmission cables, energy storage systems, fault current limiters, generators and motors—many prototypes of which are being pursued in technologically advanced countries. There is a broad consensus that the prototype stage for high-current-high-field superconducting applications is nearing its end and that large scale applications are technologically feasible. However full industrialization of large-scale superconducting technologies in electric utility applications will benefit from continuous improvement in critical current, lower ac loss, higher strength and other vital conductor properties. The establishment of optimal procedures for the system design accompanying scale-up is a second vital task. As system design is dependent on material development, there is a critical need to study the key issues in developing high performance superconducting materials. The emphases of MEM07 were The mechanical properties of superconductors including the influence of stress and strain on the critical current of practical conductors including YBCO and ReBCO coated conductors, BSCCO tapes, MgB2 wires and Nb3Sn filamentary conductors. The intrinsic strain effects on critical current density in Nb3Sn, YBCO, BSCCO and MgB2. Recent advances in critical current, the mechanical properties and the reduction in ac losses of HTS tapes and wires. The compositional and microstructural dependence of E-J characteristics and explanations based on flux pinning, grain boundary weak-links and other mechanisms. Standardized test-methods: international cooperative research work to establish test methods for assessing the mechano-electromagnetic properties of superconductors based on the activities of IEC/TC90 and VAMAS/TWA-16. More than 60 researchers from more than 12 countries attended the MEM07 workshop, and about 40 presentations were made. A small selection of papers (15) from the workshop are included in this special issue of Superconductor Science and Technology. Taken together with papers published at earlier MEM meetings, this issue provides an updated view of some of the current state-of-the-art research in the mechano-electromagnetic properties of composite superconductors. The workshop was organized under the activities of the NEDO Grant Project (Applied Superconductivity, 2004EA004) and VAMAS/TWA-16. The meeting was organized by a committee composed of David Larbalestier (Conference Chair) aided by MEM05 and MEM06 Conference Chairs Kozo Osamura (Research Institute for Applied Sciences, Kyoto, Japan), Damian Hampshire (Durham University, UK) and Arman Nyilas (CEME). The Program Committee was composed of Ettore Salpietro (European Fusion Development Agreement), Neil Mitchell (ITER), Kozo Osamura, Damian Hampshire and Arman Nyilas. We express our great thanks to all those whose efforts were key in organizing the meeting, with very special thanks to our Meeting Planner Kate Liu who organized matters large and small with discretion and great efficiency.

Pick-and-place process for sensitivity improvement of the capacitive type CMOS MEMS 2-axis tilt sensor

NASA Astrophysics Data System (ADS)

Chang, Chun-I.; Tsai, Ming-Han; Liu, Yu-Chia; Sun, Chih-Ming; Fang, Weileun

2013-09-01

This study exploits the foundry available complimentary metal-oxide-semiconductor (CMOS) process and the packaging house available pick-and-place technology to implement a capacitive type micromachined 2-axis tilt sensor. The suspended micro mechanical structures such as the spring, stage and sensing electrodes are fabricated using the CMOS microelectromechanical systems (MEMS) processes. A bulk block is assembled onto the suspended stage by pick-and-place technology to increase the proof-mass of the tilt sensor. The low temperature UV-glue dispensing and curing processes are employed to bond the block onto the stage. Thus, the sensitivity of the CMOS MEMS capacitive type 2-axis tilt sensor is significantly improved. In application, this study successfully demonstrates the bonding of a bulk solder ball of 100 µm in diameter with a 2-axis tilt sensor fabricated using the standard TSMC 0.35 µm 2P4M CMOS process. Measurements show the sensitivities of the 2-axis tilt sensor are increased for 2.06-fold (x-axis) and 1.78-fold (y-axis) after adding the solder ball. Note that the sensitivity can be further improved by reducing the parasitic capacitance and the mismatch of sensing electrodes caused by the solder ball.

High-productivity DRIE solutions for 3D-SiP and MEMS volume manufacturing

NASA Astrophysics Data System (ADS)

Puech, M.; Thevenoud, J. M.; Launay, N.; Arnal, N.; Godinat, P.; Andrieu, B.; Gruffat, J. M.

2006-12-01

Emerging 3D-SiP technologies and high volume MEMS applications require high productivity mass production DRIE systems. The Alcatel DRIE product range has recently been optimized to reach the highest process and hardware production performances. A study based on sub-micron high aspect ratio structures encountered in the most stringent 3D-SiP has been carried out. The optimization of the Bosch process parameters have shown ultra high silicon etch rate, with unrivaled uniformity and repeatability leading to excellent process yields. In parallel, most recent hardware and proprietary design optimization including vacuum pumping lines, process chamber, wafer chucks, pressure control system, gas delivery are discussed. A key factor for achieving the highest performances was the recognized expertise of Alcatel vacuum and plasma science technologies. These improvements have been monitored in a mass production environment for a mobile phone application. Field data analysis shows a significant reduction of cost of ownership thanks to increased throughput and much lower running costs. These benefits are now available for all 3D-SiP and high volume MEMS applications. The typical etched patterns include tapered trenches for CMOS imagers, through silicon via holes for die stacking, well controlled profile angle for 3D high precision inertial sensors, and large exposed area features for inkjet printer head and Silicon microphones.

MEMS-based flexible reflective analog modulators (FRAM) for projection displays: a technology review and scale-down study

NASA Astrophysics Data System (ADS)

Picard, Francis; Ilias, Samir; Asselin, Daniel; Boucher, Marc-André; Duchesne, François; Jacob, Michel; Larouche, Carl; Vachon, Carl; Niall, Keith K.; Jerominek, Hubert

2011-02-01

A MEMS based technology for projection display is reviewed. This technology relies on mechanically flexible and reflective microbridges made of aluminum alloy. A linear array of such micromirrors is combined with illumination and Schlieren optics to produce a pixels line. Each microbridge in the array is individually controlled using electrostatic actuation to adjust the pixels intensities. Results of the simulation, fabrication and characterization of these microdevices are presented. Activation voltages below 250 V with response times below 10 μs were obtained for 25 μm × 25 μm micromirrors. With appropriate actuation voltage waveforms, response times of 5 μs and less are achievable. A damage threshold of the mirrors above 8 kW/cm2 has been evaluated. Development of the technology has produced projector engines demonstrating this light modulation principle. The most recent of these engines is DVI compatible and displays VGA video streams at 60 Hz. Recently applications have emerged that impose more stringent requirements on the dimensions of the MEMS array and associated optical system. This triggered a scale down study to evaluate the minimum micromirror size achievable, the impact of this reduced size on the damage threshold and the achievable minimum size of the associated optical system. Preliminary results of this scale down study are reported. FRAM with active surface as small as 5 μm × 5 μm have been investigated. Simulations have shown that such micromirrors could be activated with 107 V to achieve f-number of 1.25. The damage threshold has been estimated for various FRAM sizes. Finally, design of a conceptual miniaturized projector based on 1000×1 array of 5 μm × 5 μm micromirrors is presented. The volume of this projector concept is about 12 cm3.

Percutaneous Steerable Robotic Tool Delivery Platform and Metal MEMS Device for Tissue Manipulation and Approximation: Closure of Patent Foramen Ovale in an Animal Model

PubMed Central

Vasilyev, Nikolay V.; Gosline, Andrew H.; Butler, Evan; Lang, Nora; Codd, Patrick J.; Yamauchi, Haruo; Feins, Eric N.; Folk, Chris R.; Cohen, Adam L.; Chen, Richard; Zurakowski, David; del Nido, Pedro J.; Dupont, Pierre E

2013-01-01

Background Beating-heart image-guided intracardiac interventions have been evolving rapidly. To extend the domain of catheter-based and transcardiac interventions into reconstructive surgery, a new robotic tool delivery platform (TDP) and tissue approximation device have been developed. Initial results employing these tools to perform patent foramen ovale (PFO) closure are described. Methods and Results A robotic TDP comprised of superelastic metal tubes provides the capability of delivering and manipulating tools and devices inside the beating heart. A new device technology is also presented that utilizes a metal-based MicroElectroMechanical Systems (MEMS) manufacturing process to produce fully-assembled and fully-functional millimeter-scale tools. As a demonstration of both technologies, a PFO creation and closure was performed in a swine model. In the first group of animals (N=10), a preliminary study was performed. The procedural technique was validated with a transcardiac handheld delivery platform and epicardial echocardiography, video-assisted cardioscopy and fluoroscopy. In the second group (N=9), the procedure was performed percutaneously using the robotic TDP under epicardial echocardiography and fluoroscopy imaging. All PFO’s were completely closed in the first group. In the second group, the PFO was not successfully created in 1 animal, and the defects were completely closed in 6 of the 8 remaining animals. Conclusions In contrast to existing robotic catheter technologies, the robotic TDP utilizes a combination of stiffness and active steerability along its length to provide the positioning accuracy and force application capability necessary for tissue manipulation. In combination with a MEMS tool technology, it can enable reconstructive procedures inside the beating heart. PMID:23899870

Micromachined fiber optic Fabry-Perot underwater acoustic probe

NASA Astrophysics Data System (ADS)

Wang, Fuyin; Shao, Zhengzheng; Hu, Zhengliang; Luo, Hong; Xie, Jiehui; Hu, Yongming

2014-08-01

One of the most important branches in the development trend of the traditional fiber optic physical sensor is the miniaturization of sensor structure. Miniature fiber optic sensor can realize point measurement, and then to develop sensor networks to achieve quasi-distributed or distributed sensing as well as line measurement to area monitoring, which will greatly extend the application area of fiber optic sensors. The development of MEMS technology brings a light path to address the problems brought by the procedure of sensor miniaturization. Sensors manufactured by MEMS technology possess the advantages of small volume, light weight, easy fabricated and low cost. In this paper, a fiber optic extrinsic Fabry-Perot interferometric underwater acoustic probe utilizing micromachined diaphragm collaborated with fiber optic technology and MEMS technology has been designed and implemented to actualize underwater acoustic sensing. Diaphragm with central embossment, where the embossment is used to anti-hydrostatic pressure which would largely deflect the diaphragm that induce interferometric fringe fading, has been made by double-sided etching of silicon on insulator. By bonding the acoustic-sensitive diaphragm as well as a cleaved fiber end in ferrule with an outer sleeve, an extrinsic Fabry-Perot interferometer has been constructed. The sensor has been interrogated by quadrature-point control method and tested in field-stable acoustic standing wave tube. Results have been shown that the recovered signal detected by the sensor coincided well with the corresponding transmitted signal and the sensitivity response was flat in frequency range from 10 Hz to 2kHz with the value about -154.6 dB re. 1/μPa. It has been manifest that the designed sensor could be used as an underwater acoustic probe.

Urban MEMS based seismic network for post-earthquakes rapid disaster assessment

NASA Astrophysics Data System (ADS)

D'Alessandro, Antonino; Luzio, Dario; D'Anna, Giuseppe

2014-05-01

Life losses following disastrous earthquake depends mainly by the building vulnerability, intensity of shaking and timeliness of rescue operations. In recent decades, the increase in population and industrial density has significantly increased the exposure to earthquakes of urban areas. The potential impact of a strong earthquake on a town center can be reduced by timely and correct actions of the emergency management centers. A real time urban seismic network can drastically reduce casualties immediately following a strong earthquake, by timely providing information about the distribution of the ground shaking level. Emergency management centers, with functions in the immediate post-earthquake period, could be use this information to allocate and prioritize resources to minimize loss of human life. However, due to the high charges of the seismological instrumentation, the realization of an urban seismic network, which may allow reducing the rate of fatalities, has not been achieved. Recent technological developments in MEMS (Micro Electro-Mechanical Systems) technology could allow today the realization of a high-density urban seismic network for post-earthquakes rapid disaster assessment, suitable for the earthquake effects mitigation. In the 1990s, MEMS accelerometers revolutionized the automotive-airbag system industry and are today widely used in laptops, games controllers and mobile phones. Due to their great commercial successes, the research into and development of MEMS accelerometers are actively pursued around the world. Nowadays, the sensitivity and dynamics of these sensors are such to allow accurate recording of earthquakes with moderate to strong magnitude. Due to their low cost and small size, the MEMS accelerometers may be employed for the realization of high-density seismic networks. The MEMS accelerometers could be installed inside sensitive places (high vulnerability and exposure), such as schools, hospitals, public buildings and places of worship. The waveforms recorded could be promptly used to determine ground-shaking parameters, like peak ground acceleration/velocity/displacement, Arias and Housner intensity, that could be all used to create, few seconds after a strong earthquakes, shaking maps at urban scale. These shaking maps could allow to quickly identify areas of the town center that have had the greatest earthquake resentment. When a strong seismic event occur, the beginning of the ground motion observed at the site could be used to predict the ensuing ground motion at the same site and so to realize a short term earthquake early warning system. The data acquired after a moderate magnitude earthquake, would provide valuable information for the detail seismic microzonation of the area based on direct earthquake shaking observations rather than from a model-based or indirect methods. In this work, we evaluate the feasibility and effectiveness of such seismic network taking in to account both technological, scientific and economic issues. For this purpose, we have simulated the creation of a MEMS based urban seismic network in a medium size city. For the selected town, taking into account the instrumental specifics, the array geometry and the environmental noise, we investigated the ability of the planned network to detect and measure earthquakes of different magnitude generated from realistic near seismogentic sources.

1998 IEEE Aerospace Conference. Proceedings.

NASA Astrophysics Data System (ADS)

The following topics were covered: science frontiers and aerospace; flight systems technologies; spacecraft attitude determination and control; space power systems; smart structures and dynamics; military avionics; electronic packaging; MEMS; hyperspectral remote sensing for GVP; space laser technology; pointing, control, tracking and stabilization technologies; payload support technologies; protection technologies; 21st century space mission management and design; aircraft flight testing; aerospace test and evaluation; small satellites and enabling technologies; systems design optimisation; advanced launch vehicles; GPS applications and technologies; antennas and radar; software and systems engineering; scalable systems; communications; target tracking applications; remote sensing; advanced sensors; and optoelectronics.

Design of a MEMS-Based Oscillator Using 180nm CMOS Technology.

PubMed

Roy, Sukanta; Ramiah, Harikrishnan; Reza, Ahmed Wasif; Lim, Chee Cheow; Ferrer, Eloi Marigo

2016-01-01

Micro-electro mechanical system (MEMS) based oscillators are revolutionizing the timing industry as a cost effective solution, enhanced with more features, superior performance and better reliability. The design of a sustaining amplifier was triggered primarily to replenish MEMS resonator's high motion losses due to the possibility of their 'system-on-chip' integrated circuit solution. The design of a sustaining amplifier observing high gain and adequate phase shift for an electrostatic clamp-clamp (C-C) beam MEMS resonator, involves the use of an 180nm CMOS process with an unloaded Q of 1000 in realizing a fixed frequency oscillator. A net 122dBΩ transimpedance gain with adequate phase shift has ensured 17.22MHz resonant frequency oscillation with a layout area consumption of 0.121 mm2 in the integrated chip solution, the sustaining amplifier draws 6.3mW with a respective phase noise of -84dBc/Hz at 1kHz offset is achieved within a noise floor of -103dBC/Hz. In this work, a comparison is drawn among similar design studies on the basis of a defined figure of merit (FOM). A low phase noise of 1kHz, high figure of merit and the smaller size of the chip has accredited to the design's applicability towards in the implementation of a clock generative integrated circuit. In addition to that, this complete silicon based MEMS oscillator in a monolithic solution has offered a cost effective solution for industrial or biomedical electronic applications.

Cost-Effectiveness of Remote Cardiac Monitoring With the CardioMEMS Heart Failure System.

PubMed

Schmier, Jordana K; Ong, Kevin L; Fonarow, Gregg C

2017-07-01

Heart failure (HF) is a leading cause of cardiovascular mortality in the United States and presents a substantial economic burden. A recently approved implantable wireless pulmonary artery pressure remote monitor, the CardioMEMS HF System, has been shown to be effective in reducing hospitalizations among New York Heart Association (NYHA) class III HF patients. The objective of this study was to estimate the cost-effectiveness of this remote monitoring technology compared to standard of care treatment for HF. A Markov cohort model relying on the CHAMPION (CardioMEMS Heart Sensor Allows Monitoring of Pressure to Improve Outcomes in NYHA Class III Heart Failure Patients) clinical trial for mortality and hospitalization data, published sources for cost data, and a mix of CHAMPION data and published sources for utility data, was developed. The model compares outcomes over 5 years for implanted vs standard of care patients, allowing patients to accrue costs and utilities while they remain alive. Sensitivity analyses explored uncertainty in input parameters. The CardioMEMS HF System was found to be cost-effective, with an incremental cost-effectiveness ratio of $44,832 per quality-adjusted life year (QALY). Sensitivity analysis found the model was sensitive to the device cost and to whether mortality benefits were sustained, although there were no scenarios in which the cost/QALY exceeded $100,000. Compared with standard of care, the CardioMEMS HF System was cost-effective when leveraging trial data to populate the model. © 2017 Wiley Periodicals, Inc.

Human organ-on-a-chip BioMEMS devices for testing new diagnostic and therapeutic strategies

NASA Astrophysics Data System (ADS)

Leary, James F.; Key, Jaehong; Vidi, Pierre-Alexandre; Cooper, Christy L.; Kole, Ayeeshik; Reece, Lisa M.; Lelièvre, Sophie A.

2013-03-01

MEMS human "organs-on-a-chip" can be used to create model human organ systems for developing new diagnostic and therapeutic strategies. They represent a promising new strategy for rapid testing of new diagnostic and therapeutic approaches without the need for involving risks to human subjects. We are developing multicomponent, superparamagnetic and fluorescent nanoparticles as X-ray and MRI contrast agents for noninvasive multimodal imaging and for antibody- or peptide-targeted drug delivery to tumor and precancerous cells inside these artificial organ MEMS devices. Magnetic fields can be used to move the nanoparticles "upstream" to find their target cells in an organs-on-achip model of human ductal breast cancer. Theoretically, unbound nanoparticles can then be removed by reversing the magnetic field to give a greatly enhanced image of tumor cells within these artificial organ structures. Using branched PDMS microchannels and 3D tissue engineering of normal and malignant human breast cancer cells inside those MEMS channels, we can mimic the early stages of human ductal breast cancer with the goal to improve the sensitivity and resolution of mammography and MRI of very small tumors and test new strategies for treatments. Nanomedical systems can easily be imaged by multicolor confocal microscopy inside the artificial organs to test targeting and therapeutic responses including the differential viability of normal and tumor cells during treatments. Currently we are using 2-dimensional MEMS structures, but these studies can be extended to more complex 3D structures using new 3D printing technologies.

Large-aperture MOEMS Fabry-Perot interferometer for miniaturized spectral imagers

NASA Astrophysics Data System (ADS)

Rissanen, Anna; Langner, Andreas; Viherkanto, Kai; Mannila, Rami

2015-02-01

VTT's optical MEMS Fabry-Perot interferometers (FPIs) are tunable optical filters, which enable miniaturization of spectral imagers into small, mass producible hand-held sensors with versatile optical measurement capabilities. FPI technology has also created a basis for various hyperspectral imaging instruments, ranging from nanosatellites, environmental sensing and precision agriculture with UAVs to instruments for skin cancer detection. Until now, these application demonstrations have been mostly realized with piezo-actuated FPIs fabricated by non-monolithical assembly method, suitable for achieving very large optical apertures and with capacity to small-to-medium volumes; however large-volume production of MEMS manufacturing supports the potential for emerging spectral imaging applications also in large-volume applications, such as in consumer/mobile products. Previously reported optical apertures of MEMS FPIs in the visible range have been up to 2 mm in size; this paper presents the design, successful fabrication and characterization of MEMS FPIs for central wavelengths of λ = 500 nm and λ = 650 nm with optical apertures up to 4 mm in diameter. The mirror membranes of the FPI structures consist of ALD (atomic layer deposited) TiO2-Al2O3 λ/4- thin film Bragg reflectors, with the air gap formed by sacrificial polymer etching in O2 plasma. The entire fabrication process is conducted below 150 °C, which makes it possible to monolithically integrate the filter structures on other ICdevices such as detectors. The realized MEMS devices are aimed for nanosatellite space application as breadboard hyperspectral imager demonstrators.

Cantilever-type Thermal Microactuators Fabricated by SOI-MUMPs with U-type and I-type Configurations

NASA Astrophysics Data System (ADS)

Osada, Takahiro; Ochiai, Kuniyuki; Osada, Kazuki; Muro, Hideo

Recently, the micro fluid systems have been extensively studied, where microactuators such as micro valves fabricated by MEMS technology are essential for realizing these systems. In this paper thermal microactuators with U-type and I-type shapes fabricated by SOI-MUMPs technology have been investigated for optimizing their configurations.

Radio frequency telemetry system for sensors and actuators

NASA Technical Reports Server (NTRS)

Simons, Rainee N. (Inventor); Miranda, Felix A. (Inventor)

2003-01-01

The present invention discloses and teaches apparatus for combining Radio Frequency (RF) technology with novel micro-inductor antennas and signal processing circuits for RF telemetry of real time, measured data, from microelectromechanical system (MEMS) sensors, through electromagnetic coupling with a remote powering/receiving device. Such technology has many applications, but is especially useful in the biomedical area.

Radio Frequency Telemetry System for Sensors and Actuators

NASA Technical Reports Server (NTRS)

Simons, Rainee N. (Inventor); Miranda, Felix A. (Inventor)

2003-01-01

The present invention discloses and teaches apparatus for combining Radio Frequency (RF) technology with novel micro-inductor antennas and signal processing circuits for RF telemetry of real time, measured data, from microelectromechanical system (MEMS) sensors, through electromagnetic coupling with a remote poweringheceiving device. Such technology has many applications, but is especially useful in the biomedical area.

Nanoelectronics and More-than-Moore at IMEC

NASA Astrophysics Data System (ADS)

Cartuyvels, Rudi; Biesemans, Serge; Vandervorst, Wilfried; De Boeck, Jo

2011-11-01

This paper presents an overview of imec's R&D addressing the challenges of CMOS scaling towards the 10 nm node and its outlook beyond. In addition to the relentless geometrical shrinks, opportunities to further increase nanoelectronic system functionality and performance by co-integration and chip stacking technologies combined with emerging MEMS and optoelectronic technologies will be presented.

Gyroscope Technology and Applications: A Review in the Industrial Perspective

PubMed Central

Cuccovillo, Antonello; Vaiani, Lorenzo; De Carlo, Martino

2017-01-01

This paper is an overview of current gyroscopes and their roles based on their applications. The considered gyroscopes include mechanical gyroscopes and optical gyroscopes at macro- and micro-scale. Particularly, gyroscope technologies commercially available, such as Mechanical Gyroscopes, silicon MEMS Gyroscopes, Ring Laser Gyroscopes (RLGs) and Fiber-Optic Gyroscopes (FOGs), are discussed. The main features of these gyroscopes and their technologies are linked to their performance. PMID:28991175

Sources of stress gradients in electrodeposited Ni MEMS.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hearne, Sean Joseph; Floro, Jerrold Anthony; Dyck, Christopher William

2004-06-01

The ability of future integrated metal-semiconductor micro-systems such as RF MEMS to perform highly complex functions will depend on developing freestanding metal structures that offer improved conductivity and reflectivity over polysilicon structures. For example, metal-based RF MEMS technology could replace the bulky RF system presently used in communications, navigation, and avionics systems. However, stress gradients that induce warpage of active components have prevented the implementation of this technology. Figure 1, is an interference micrograph image of a series of cantilever beams fabricated from electrodeposited Ni. The curvature in the beams was the result of stress gradients intrinsic to the electrodepositionmore » process. To study the sources of the stress in electrodeposition of Ni we have incorporated a wafer curvature based stress sensor, the multibeam optical stress sensor, into an electrodeposition cell. We have determined that there are two regions of stress induced by electrodepositing Ni from a sulfamate-based bath (Fig 2). The stress evolution during the first region, 0-1000{angstrom}, was determined to be dependent only on the substrate material (Au vs. Cu), whereas the stress evolution during the second region, >1000{angstrom}, was highly dependent on the deposition conditions. In this region, the stress varied from +0.5 GPa to -0.5GPa, depending solely on the deposition rate. We examined four likely sources for the compressive intrinsic stress, i.e. reduction in tensile stress, and determined that only the adatom diffusion into grain boundaries model of Sheldon, et al. could account for the observed compressive stress. In the presentation, we shall discuss the compressive stress generation mechanisms considered and the ramifications of these results on fabrication of electrodeposited Ni for MEMS applications.« less

Optical MEMS for Earth observation

NASA Astrophysics Data System (ADS)

Liotard, Arnaud; Viard, Thierry; Noell, Wilfried; Zamkotsian, Frédéric; Freire, Marco; Guldimann, Benedikt; Kraft, Stefan

2017-11-01

Due to the relatively large number of optical Earth Observation missions at ESA, this area is interesting for new space technology developments. In addition to their compactness, scalability and specific task customization, optical MEMS could generate new functions not available with current technologies and are thus candidates for the design of future space instruments. Most mature components for space applications are the digital mirror arrays, the micro-deformable mirrors, the programmable micro diffraction gratings and tiltable micromirrors. A first selection of market-pull and techno-push concepts is done. In addition, some concepts are coming from outside Earth Observation. Finally two concepts are more deeply analyzed. The first concept is a programmable slit for straylight control for space spectro-imagers. This instrument is a push-broom spectroimager for which some images cannot be exploited because of bright sources in the field-of-view. The proposed concept consists in replacing the current entrance spectrometer slit by an active row of micro-mirrors. The MEMS will permit to dynamically remove the bright sources and then to obtain a field-of-view with an optically enhanced signal-to-noise ratio. The second concept is a push-broom imager for which the acquired spectrum can be tuned by optical MEMS. This system is composed of two diffractive elements and a digital mirror array. The first diffractive element spreads the spectrum. A micromirror array is set at the location of the spectral focal plane. By putting the micro-mirrors ON or OFF, we can select parts of field-of-view or spectrum. The second diffractive element then recombines the light on a push-broom detector. Dichroics filters, strip filter, band-pass filter could be replaced by a unique instrument.

Syngas generation from n-butane with an integrated MEMS assembly for gas processing in micro-solid oxide fuel cell systems.

PubMed

Bieberle-Hütter, A; Santis-Alvarez, A J; Jiang, B; Heeb, P; Maeder, T; Nabavi, M; Poulikakos, D; Niedermann, P; Dommann, A; Muralt, P; Bernard, A; Gauckler, L J

2012-11-21

An integrated system of a microreformer and a carrier allowing for syngas generation from liquefied petroleum gas (LPG) for micro-SOFC application is discussed. The microreformer with an overall size of 12.7 mm × 12.7 mm × 1.9 mm is fabricated with micro-electro-mechanical system (MEMS) technologies. As a catalyst, a special foam-like material made from ceria-zirconia nanoparticles doped with rhodium is used to fill the reformer cavity of 58.5 mm(3). The microreformer is fixed onto a microfabricated structure with built-in fluidic channels and integrated heaters, the so-called functional carrier. It allows for thermal decoupling of the cold inlet gas and the hot fuel processing zone. Two methods for heating the microreformer are compared in this study: a) heating in an external furnace and b) heating with the two built-in heaters on the functional carrier. With both methods, high butane conversion rates of 74%-85% are obtained at around 550 °C. In addition, high hydrogen and carbon monoxide yields and selectivities are achieved. The results confirm those from classical lab reformers built without MEMS technology (N. Hotz et al., Chem. Eng. Sci., 2008, 63, 5193; N. Hotz et al., Appl. Catal., B, 2007, 73, 336). The material combinations and processing techniques enable syngas production with the present MEMS based microreformer with high performance for temperatures up to 700 °C. The functional carrier is the basis for a new platform, which can integrate the micro-SOFC membranes and the gas processing unit as subsystem of an entire micro-SOFC system.

Evaluation of MEMS-based in-place inclinometers in cold regions : [summary].

DOT National Transportation Integrated Search

2013-03-01

Inclinometer probes are used to measure ground movement. While an industry standard, this technology has drawbacks, including costly trips for manual measurements, : operator error, and limited measurements due to casing deformation. Relatively new M...

Evaluation of MEMS-based in-place inclinometers in cold regions.

DOT National Transportation Integrated Search

2013-03-01

Inclinometer probes are used to measure ground movement. While an industry standard, this technology has drawbacks, including costly trips for manual measurements, : operator error, and limited measurements due to casing deformation. Relatively new M...

Sampling and Control Circuit Board for an Inertial Measurement Unit

NASA Technical Reports Server (NTRS)

Chelmins, David; Powis, Rick

2012-01-01

Spacesuit navigation is one component of NASA s efforts to return humans to the Moon. Studies performed at the NASA Glenn Research Center (GRC) considered various navigation technologies and filtering approaches to enable navigation on the lunar surface. As part of this effort, microelectromechanical systems (MEMS) inertial measurement units (IMUs) were studied to determine if they could supplement a radiometric infrastructure. MEMS IMUs were included in the Lunar Extra-Vehicular Activity Crewmember Location Determination System (LECLDS) testbed during NASA s annual Desert Research and Technology Studies (D-RATS) event in 2009 and 2010. The testbed included one IMU in 2009 and three IMUs in 2010, along with a custom circuit board interfacing between the navigation processor and each IMU. The board was revised for the 2010 test, and this paper documents the design details of this latest revision of the interface circuit board and firmware.

Hemispherical array of sensors with contractively wrapped polymer petals for flow sensing

NASA Astrophysics Data System (ADS)

Kanhere, Elgar; Wang, Nan; Kottapalli, Ajay Giri Prakash; Miao, Jianmin; Triantafyllou, Michael

2017-11-01

Hemispherical arrays have inherent advantages that allow simultaneous detection of flow speed and direction due to their shape. Though MEMS technology has progressed leaps and bounds, fabrication of array of sensors on a hemispherical surface is still a challenge. In this work, a novel approach of constructing hemispherical array is presented which employs a technique of contractively wrapping a hemispherical surface with flexible liquid crystal polymer petals. This approach also leverages the offerings from rapid prototyping technology and established standard MEMS fabrication processes. Hemispherical arrays of piezoresistive sensors are constructed with two types of petal wrappings, 4-petals and 8-petals, on a dome. The flow sensing and direction detection abilities of the dome are evaluated through experiments in wind tunnel. Experimental results demonstrate that a dome equipped with a dense array of sensors can provide information pertaining to the stimulus, through visualization of output profile over the entire surface.

RF MEMS and Their Applications in NASA's Space Communication Systems

NASA Technical Reports Server (NTRS)

Williams, W. Daniel; Ponchak, George E.; Simons, Rainee N.; Zaman, Afroz; Kory, Carol; Wintucky, Edwin; Wilson, Jeffrey D.; Scardelletti, Maximilian; Lee, Richard; Nguyen, Hung

2001-01-01

Radio frequency (RF) and microwave communication systems rely on frequency, amplitude, and phase control circuits to efficiently use the available spectrum. Phase control circuits are required for electronically scanning phase array antennas that enable radiation pattern shaping, scanning, and hopping. Two types of phase shifters, which are the phase control circuits, are most often used. The first is comprised of two circuits with different phase characteristics such as two transmission lines of different lengths or a high pass and low pass filter and a switch that directs the RF power through one of the two circuits. Alternatively, a variable capacitor, or varactor, is used to change the effective electrical path length of a transmission line, which changes the phase characteristics. Filter banks are required for the diplexer at the front end of wide band communication satellites. These filters greatly increase the size and mass of the RF/microwave systems, but smaller diplexers may be made with a low loss varactor or a group of capacitors, a switch and an inductor.

Fully parameterized model of a voltage-driven capacitive coupled micromachined ohmic contact switch for RF applications

NASA Astrophysics Data System (ADS)

Heeb, Peter; Tschanun, Wolfgang; Buser, Rudolf

2012-03-01

A comprehensive and completely parameterized model is proposed to determine the related electrical and mechanical dynamic system response of a voltage-driven capacitive coupled micromechanical switch. As an advantage over existing parameterized models, the model presented in this paper returns within few seconds all relevant system quantities necessary to design the desired switching cycle. Moreover, a sophisticated and detailed guideline is given on how to engineer a MEMS switch. An analytical approach is used throughout the modelling, providing representative coefficients in a set of two coupled time-dependent differential equations. This paper uses an equivalent mass moving along the axis of acceleration and a momentum absorption coefficient. The model describes all the energies transferred: the energy dissipated in the series resistor that models the signal attenuation of the bias line, the energy dissipated in the squeezed film, the stored energy in the series capacitor that represents a fixed separation in the bias line and stops the dc power in the event of a short circuit between the RF and dc path, the energy stored in the spring mechanism, and the energy absorbed by mechanical interaction at the switch contacts. Further, the model determines the electrical power fed back to the bias line. The calculated switching dynamics are confirmed by the electrical characterization of the developed RF switch. The fabricated RF switch performs well, in good agreement with the modelled data, showing a transition time of 7 µs followed by a sequence of bounces. Moreover, the scattering parameters exhibit an isolation in the off-state of >8 dB and an insertion loss in the on-state of <0.6 dB up to frequencies of 50 GHz. The presented model is intended to be integrated into standard circuit simulation software, allowing circuit engineers to design the switch bias line, to minimize induced currents and cross actuation, as well as to find the mechanical structure dimensions necessary for the desired switching time and actuation voltage waveform. Moreover, process related design rules can be automatically verified.

High quality factor single-crystal diamond mechanical resonators

NASA Astrophysics Data System (ADS)

Ovartchaiyapong, P.; Pascal, L. M. A.; Myers, B. A.; Lauria, P.; Bleszynski Jayich, A. C.

2012-10-01

Single-crystal diamond is a promising material for microelectromechanical systems (MEMs) because of its low mechanical loss, compatibility with extreme environments, and built-in interface to high-quality spin centers. But its use has been limited by challenges in processing and growth. We demonstrate a wafer bonding-based technique to form diamond on insulator, from which we make single-crystal diamond micromechanical resonators with mechanical quality factors as high as 338 000 at room temperature. Variable temperature measurements down to 10 K reveal a nonmonotonic dependence of quality factor on temperature. These resonators enable integration of single-crystal diamond into MEMs technology for classical and quantum applications.

Applications of Ferro-Nanofluid on a Micro-Transformer

PubMed Central

Tsai, Tsung-Han; Kuo, Long-Sheng; Chen, Ping-Hei; Lee, Da-sheng; Yang, Chin-Ting

2010-01-01

An on-chip transformer with a ferrofluid magnetic core has been developed and tested. The transformer consists of solenoid-type coil and a magnetic core of ferrofluid, with the former fabricated by MEMS technology and the latter by a chemical co-precipitation method. The performance of the MEMS transformer with a ferrofluid magnetic core was measured and simulated with frequencies ranging from 100 kHz to 100 MHz. Experimental results reveal that the presence of the ferrofluid increases the inductance of coils and the coupling coefficient of transformer; however, it also increases the resistance owing to the lag between the external magnetic field and the magnetization of the material. PMID:22163647

Applications of ferro-nanofluid on a micro-transformer.

PubMed

Tsai, Tsung-Han; Kuo, Long-Sheng; Chen, Ping-Hei; Lee, Da-Sheng; Yang, Chin-Ting

2010-01-01

An on-chip transformer with a ferrofluid magnetic core has been developed and tested. The transformer consists of solenoid-type coil and a magnetic core of ferrofluid, with the former fabricated by MEMS technology and the latter by a chemical co-precipitation method. The performance of the MEMS transformer with a ferrofluid magnetic core was measured and simulated with frequencies ranging from 100 kHz to 100 MHz. Experimental results reveal that the presence of the ferrofluid increases the inductance of coils and the coupling coefficient of transformer; however, it also increases the resistance owing to the lag between the external magnetic field and the magnetization of the material.

System-in Package of Integrated Humidity Sensor Using CMOS-MEMS Technology.

PubMed

Lee, Sung Pil

2015-10-01

Temperature/humidity microchips with micropump were fabricated using a CMOS-MEMS process and combined with ZigBee modules to implement a sensor system in package (SIP) for a ubiquitous sensor network (USN) and/or a wireless communication system. The current of a diode temperature sensor to temperature and a normalized current of FET humidity sensor to relative humidity showed linear characteristics, respectively, and the use of the micropump has enabled a faster response. A wireless reception module using the same protocol as that in transmission systems processed the received data within 10 m and showed temperature and humidity values in the display.

MEMS deformable mirror for wavefront correction of large telescopes

NASA Astrophysics Data System (ADS)

Manhart, Sigmund; Vdovin, Gleb; Collings, Neil; Sodnik, Zoran; Nikolov, Susanne; Hupfer, Werner

2017-11-01

A 50 mm diameter membrane mirror was designed and manufactured at TU Delft. It is made from bulk silicon by micromachining - a technology primarily used for micro-electromechanical systems (MEMS). The mirror unit is equipped with 39 actuator electrodes and can be electrostatically deformed to correct wavefront errors in optical imaging systems. Performance tests on the deformable mirror were carried out at Astrium GmbH using a breadboard setup with a wavefront sensor and a closed-loop control system. It was found that the deformable membrane mirror is well suited for correction of low order wavefront errors as they must be expected in lightweighted space telescopes.

Infusion of Emerging Technologies and New Teaching Methods into the Mechanical Engineering Curriculum at the City College of New York

ERIC Educational Resources Information Center

Delale, Feridun; Liaw, Benjamin M.; Jiji, Latif M.; Voiculescu, Ioana; Yu, Honghui

2011-01-01

From October 2003 to April 2008 a systemic reform of the Mechanical Engineering program at The City College of New York was undertaken with the goal of incorporating emerging technologies (such as nanotechnology, biotechnology, Micro-Electro-Mechanical Systems (MEMS), intelligent systems) and new teaching methodologies (such as project based…

Introduction to Micro/Nanofabrication

NASA Astrophysics Data System (ADS)

Ziaie, Babak; Baldi, Antonio; Atashbar, Massood

This chapter outlines and discusses important micro- and nanofabrication techniques. We start with the most basic methods borrowed from the integrated circuit (IC) industry, such as thin film deposition, lithography and etching, and then move on to look at MEMS and nanofabrication technologies. We cover a broad range of dimensions, from the micron to the nanometer scale. Although most of the current research is geared towards the nanodomain, a good understanding of top-down methods for fabricating micron-sized objects can aid our understanding of this research. Due to space constraints, we have focused here on the most important technologies; in the microdomain these include surface, bulk and high aspect ratio micromachining; in the nanodomain we concentrate on e-beam lithography, epitaxial growth, template manufacturing and self-assembly. MEMS technology is maturing rapidly, with some new technologies displacing older ones that have proven to be unsuited to manufacture on a commercial scale. However, the jury is still out on methods used in the nanodomain, although it appears that bottom-up methods are the most feasible, and these will have a major impact in a variety of application areas such as biology, medicine, environmental monitoring and nanoelectronics.

Biomimetic patterned surfaces for controllable friction in micro- and nanoscale devices

NASA Astrophysics Data System (ADS)

Singh, Arvind; Suh, Kahp-Yang

2013-12-01

Biomimetics is the study and simulation of biological systems for desired functional properties. It involves the transformation of underlying principles discovered in nature into man-made technologies. In this context, natural surfaces have significantly inspired and motivated new solutions for micro- and nano-scale devices (e.g., Micro/Nano-Electro-Mechanical Systems, MEMS/NEMS) towards controllable friction, during their operation. As a generic solution to reduce friction at small scale, various thin films/coatings have been employed in the last few decades. In recent years, inspiration from `Lotus Effect' has initiated a new research direction for controllable friction with biomimetic patterned surfaces. By exploiting the intrinsic hydrophobicity and ability to reduce contact area, such micro- or nano-patterned surfaces have demonstrated great strength and potential for applications in MEMS/NEMS devices. This review highlights recent advancements on the design, development and performance of these biomimetic patterned surfaces. Also, we present some hybrid approaches to tackle current challenges in biomimetic tribological applications for MEMS/NEMS devices.

High sensitivity capacitive MEMS microphone with spring supported diaphragm

NASA Astrophysics Data System (ADS)

Mohamad, Norizan; Iovenitti, Pio; Vinay, Thurai

2007-12-01

Capacitive microphones (condenser microphones) work on a principle of variable capacitance and voltage by the movement of its electrically charged diaphragm and back plate in response to sound pressure. There has been considerable research carried out to increase the sensing performance of microphones while reducing their size to cater for various modern applications such as mobile communication and hearing aid devices. This paper reviews the development and current performance of several condenser MEMS microphone designs, and introduces a microphone with spring supported diaphragm to further improve condenser microphone performance. The numerical analysis using Coventor FEM software shows that this new microphone design has a higher mechanical sensitivity compared to the existing edge clamped flat diaphragm condenser MEMS microphone. The spring supported diaphragm is shown to have a flat frequency response up to 7 kHz and more stable under the variations of the diaphragm residual stress. The microphone is designed to be easily fabricated using the existing silicon fabrication technology and the stability against the residual stress increases its reproducibility.

The Electrophysiological MEMS Device with Micro Channel Array for Cellular Network Analysis

NASA Astrophysics Data System (ADS)

Tonomura, Wataru; Kurashima, Toshiaki; Takayama, Yuzo; Moriguchi, Hiroyuki; Jimbo, Yasuhiko; Konishi, Satoshi

This paper describes a new type of MCA (Micro Channel Array) for simultaneous multipoint measurement of cellular network. Presented MCA employing the measurement principles of the patch-clamp technique is designed for advanced neural network analysis which has been studied by co-authors using 64ch MEA (Micro Electrode Arrays) system. First of all, sucking and clamping of cells through channels of developed MCA is expected to improve electrophysiological signal detections. Electrophysiological sensing electrodes integrated around individual channels of MCA by using MEMS (Micro Electro Mechanical System) technologies are electrically isolated for simultaneous multipoint measurement. In this study, we tested the developed MCA using the non-cultured rat's cerebral cortical slice and the hippocampal neurons. We could measure the spontaneous action potential of the slice simultaneously at multiple points and culture the neurons on developed MCA. Herein, we describe the experimental results together with the design and fabrication of the electrophysiological MEMS device with MCA for cellular network analysis.

An integrated MEMS infrastructure for fuel processing: hydrogen generation and separation for portable power generation

NASA Astrophysics Data System (ADS)

Varady, M. J.; McLeod, L.; Meacham, J. M.; Degertekin, F. L.; Fedorov, A. G.

2007-09-01

Portable fuel cells are an enabling technology for high efficiency and ultra-high density distributed power generation, which is essential for many terrestrial and aerospace applications. A key element of fuel cell power sources is the fuel processor, which should have the capability to efficiently reform liquid fuels and produce high purity hydrogen that is consumed by the fuel cells. To this end, we are reporting on the development of two novel MEMS hydrogen generators with improved functionality achieved through an innovative process organization and system integration approach that exploits the advantages of transport and catalysis on the micro/nano scale. One fuel processor design utilizes transient, reverse-flow operation of an autothermal MEMS microreactor with an intimately integrated, micromachined ultrasonic fuel atomizer and a Pd/Ag membrane for in situ hydrogen separation from the product stream. The other design features a simpler, more compact planar structure with the atomized fuel ejected directly onto the catalyst layer, which is coupled to an integrated hydrogen selective membrane.

INS/GNSS Integration for Aerobatic Flight Applications and Aircraft Motion Surveying.

PubMed

V Hinüber, Edgar L; Reimer, Christian; Schneider, Tim; Stock, Michael

2017-04-26

This paper presents field tests of challenging flight applications obtained with a new family of lightweight low-power INS/GNSS ( inertial navigation system/global satellite navigation system ) solutions based on MEMS ( micro-electro-mechanical- sensor ) machined sensors, being used for UAV ( unmanned aerial vehicle ) navigation and control as well as for aircraft motion dynamics analysis and trajectory surveying. One key is a 42+ state extended Kalman-filter-based powerful data fusion, which also allows the estimation and correction of parameters that are typically affected by sensor aging, especially when applying MEMS-based inertial sensors, and which is not yet deeply considered in the literature. The paper presents the general system architecture, which allows iMAR Navigation the integration of all classes of inertial sensors and GNSS ( global navigation satellite system ) receivers from very-low-cost MEMS and high performance MEMS over FOG ( fiber optical gyro ) and RLG ( ring laser gyro ) up to HRG ( hemispherical resonator gyro ) technology, and presents detailed flight test results obtained under extreme flight conditions. As a real-world example, the aerobatic maneuvers of the World Champion 2016 (Red Bull Air Race) are presented. Short consideration is also given to surveying applications, where the ultimate performance of the same data fusion, but applied on gravimetric surveying, is discussed.

INS/GNSS Integration for Aerobatic Flight Applications and Aircraft Motion Surveying

PubMed Central

v. Hinüber, Edgar L.; Reimer, Christian; Schneider, Tim; Stock, Michael

2017-01-01

This paper presents field tests of challenging flight applications obtained with a new family of lightweight low-power INS/GNSS (inertial navigation system/global satellite navigation system) solutions based on MEMS (micro-electro-mechanical- sensor) machined sensors, being used for UAV (unmanned aerial vehicle) navigation and control as well as for aircraft motion dynamics analysis and trajectory surveying. One key is a 42+ state extended Kalman-filter-based powerful data fusion, which also allows the estimation and correction of parameters that are typically affected by sensor aging, especially when applying MEMS-based inertial sensors, and which is not yet deeply considered in the literature. The paper presents the general system architecture, which allows iMAR Navigation the integration of all classes of inertial sensors and GNSS (global navigation satellite system) receivers from very-low-cost MEMS and high performance MEMS over FOG (fiber optical gyro) and RLG (ring laser gyro) up to HRG (hemispherical resonator gyro) technology, and presents detailed flight test results obtained under extreme flight conditions. As a real-world example, the aerobatic maneuvers of the World Champion 2016 (Red Bull Air Race) are presented. Short consideration is also given to surveying applications, where the ultimate performance of the same data fusion, but applied on gravimetric surveying, is discussed. PMID:28445417

MEMS Sensor Technologies for Human Centred Applications in Healthcare, Physical Activities, Safety and Environmental Sensing: A Review on Research Activities in Italy

PubMed Central

Ciuti, Gastone; Ricotti, Leonardo; Menciassi, Arianna; Dario, Paolo

2015-01-01

Over the past few decades the increased level of public awareness concerning healthcare, physical activities, safety and environmental sensing has created an emerging need for smart sensor technologies and monitoring devices able to sense, classify, and provide feedbacks to users’ health status and physical activities, as well as to evaluate environmental and safety conditions in a pervasive, accurate and reliable fashion. Monitoring and precisely quantifying users’ physical activity with inertial measurement unit-based devices, for instance, has also proven to be important in health management of patients affected by chronic diseases, e.g., Parkinson’s disease, many of which are becoming highly prevalent in Italy and in the Western world. This review paper will focus on MEMS sensor technologies developed in Italy in the last three years describing research achievements for healthcare and physical activity, safety and environmental sensing, in addition to smart systems integration. Innovative and smart integrated solutions for sensing devices, pursued and implemented in Italian research centres, will be highlighted, together with specific applications of such technologies. Finally, the paper will depict the future perspective of sensor technologies and corresponding exploitation opportunities, again with a specific focus on Italy. PMID:25808763

EDITORIAL: Selected papers from the 9th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2009) Selected papers from the 9th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2009)

NASA Astrophysics Data System (ADS)

Ghodssi, Reza; Livermore, Carol; Arnold, David

2010-10-01

This special section of the Journal of Micromechanics and Microengineering presents papers selected from the 9th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2009), which was held in Washington DC, USA from 1-4 December 2009. Since it was first held in Sendai, Japan in 2000, the PowerMEMS workshop has focused on small-scale systems that process, convert, or generate macroscopically significant amounts of power, typically with high power density or high energy density. In the workshop's early years, much of the research presented was on small-scale fueled systems, such as micro heat engines and micro fuel cells. The past nine years have seen a dramatic expansion in the range of technologies that are brought to bear on the challenge of high-power, small-scale systems, as well as an increase in the applications for such technologies. At this year's workshop, 158 contributed papers were presented, along with invited and plenary presentations. The papers focused on applications from micro heat engines and fuel cells, to energy harvesting and its enabling electronics, to thermal management and propulsion. Also presented were the technologies that enable these applications, such as the structuring of microscale, nanoscale and biological systems for power applications, as well as combustion and catalysis at small scales. This special section includes a selection of 12 expanded papers representing energy harvesting, chemical and fueled systems, and elastic energy storage at small scales. We would like to express our appreciation to the members of the International Steering Committee, the Technical Program Committee, the Local Organizing Committee, and to the workshop's financial supporters. We are grateful to the referees for their contributions to the review process. Finally, we would like to thank Dr Ian Forbes, the editorial staff of the Journal of Micromechanics and Microengineering, and the staff of IOP Publishing for making this special section possible.

Design of a MEMS-Based Oscillator Using 180nm CMOS Technology

PubMed Central

Roy, Sukanta; Ramiah, Harikrishnan; Reza, Ahmed Wasif; Lim, Chee Cheow; Ferrer, Eloi Marigo

2016-01-01

Micro-electro mechanical system (MEMS) based oscillators are revolutionizing the timing industry as a cost effective solution, enhanced with more features, superior performance and better reliability. The design of a sustaining amplifier was triggered primarily to replenish MEMS resonator’s high motion losses due to the possibility of their ‘system-on-chip’ integrated circuit solution. The design of a sustaining amplifier observing high gain and adequate phase shift for an electrostatic clamp-clamp (C-C) beam MEMS resonator, involves the use of an 180nm CMOS process with an unloaded Q of 1000 in realizing a fixed frequency oscillator. A net 122dBΩ transimpedance gain with adequate phase shift has ensured 17.22MHz resonant frequency oscillation with a layout area consumption of 0.121 mm2 in the integrated chip solution, the sustaining amplifier draws 6.3mW with a respective phase noise of -84dBc/Hz at 1kHz offset is achieved within a noise floor of -103dBC/Hz. In this work, a comparison is drawn among similar design studies on the basis of a defined figure of merit (FOM). A low phase noise of 1kHz, high figure of merit and the smaller size of the chip has accredited to the design’s applicability towards in the implementation of a clock generative integrated circuit. In addition to that, this complete silicon based MEMS oscillator in a monolithic solution has offered a cost effective solution for industrial or biomedical electronic applications. PMID:27391136

Sensing magnetic flux density of artificial neurons with a MEMS device.

PubMed

Tapia, Jesus A; Herrera-May, Agustin L; García-Ramírez, Pedro J; Martinez-Castillo, Jaime; Figueras, Eduard; Flores, Amira; Manjarrez, Elías

2011-04-01

We describe a simple procedure to characterize a magnetic field sensor based on microelectromechanical systems (MEMS) technology, which exploits the Lorentz force principle. This sensor is designed to detect, in future applications, the spiking activity of neurons or muscle cells. This procedure is based on the well-known capability that a magnetic MEMS device can be used to sense a small magnetic flux density. In this work, an electronic neuron (FitzHugh-Nagumo) is used to generate controlled spike-like magnetic fields. We show that the magnetic flux density generated by the hardware of this neuron can be detected with a new MEMS magnetic field sensor. This microdevice has a compact resonant structure (700 × 600 × 5 μm) integrated by an array of silicon beams and p-type piezoresistive sensing elements, which need an easy fabrication process. The proposed microsensor has a resolution of 80 nT, a sensitivity of 1.2 V.T(-1), a resonant frequency of 13.87 kHz, low power consumption (2.05 mW), quality factor of 93 at atmospheric pressure, and requires a simple signal processing circuit. The importance of our study is twofold. First, because the artificial neuron can generate well-controlled magnetic flux density, we suggest it could be used to analyze the resolution and performance of different magnetic field sensors intended for neurobiological applications. Second, the introduced MEMS magnetic field sensor may be used as a prototype to develop new high-resolution biomedical microdevices to sense magnetic fields from cardiac tissue, nerves, spinal cord, or the brain.

Measurement of the Earth tides with a MEMS gravimeter.

PubMed

Middlemiss, R P; Samarelli, A; Paul, D J; Hough, J; Rowan, S; Hammond, G D

2016-03-31

The ability to measure tiny variations in the local gravitational acceleration allows, besides other applications, the detection of hidden hydrocarbon reserves, magma build-up before volcanic eruptions, and subterranean tunnels. Several technologies are available that achieve the sensitivities required for such applications (tens of microgal per hertz(1/2)): free-fall gravimeters, spring-based gravimeters, superconducting gravimeters, and atom interferometers. All of these devices can observe the Earth tides: the elastic deformation of the Earth's crust as a result of tidal forces. This is a universally predictable gravitational signal that requires both high sensitivity and high stability over timescales of several days to measure. All present gravimeters, however, have limitations of high cost (more than 100,000 US dollars) and high mass (more than 8 kilograms). Here we present a microelectromechanical system (MEMS) device with a sensitivity of 40 microgal per hertz(1/2) only a few cubic centimetres in size. We use it to measure the Earth tides, revealing the long-term stability of our instrument compared to any other MEMS device. MEMS accelerometers--found in most smart phones--can be mass-produced remarkably cheaply, but none are stable enough to be called a gravimeter. Our device has thus made the transition from accelerometer to gravimeter. The small size and low cost of this MEMS gravimeter suggests many applications in gravity mapping. For example, it could be mounted on a drone instead of low-flying aircraft for distributed land surveying and exploration, deployed to monitor volcanoes, or built into multi-pixel density-contrast imaging arrays.

Programmable Aperture with MEMS Microshutter Arrays

NASA Technical Reports Server (NTRS)

Moseley, Samuel; Li, Mary; Kutyrev, Alexander; Kletetschka, Gunther; Fettig, Rainer

2011-01-01

A microshutter array (MSA) has been developed for use as an aperture array for multi-object selections in James Webb Space Telescope (JWST) technology. Light shields, molybdenum nitride (MoN) coating on shutters, and aluminum/aluminum oxide coatings on interior walls are put on each shutter for light leak prevention, and to enhance optical contrast. Individual shutters are patterned with a torsion flexure that permits shutters to open 90 deg. with a minimized mechanical stress concentration. The shutters are actuated magnetically, latched, and addressed electrostatically. Also, micromechanical features are tailored onto individual shutters to prevent stiction. An individual shutter consists of a torsion hinge, a shutter blade, a front electrode that is coated on the shutter blade, a backside electrode that is coated on the interior walls, and a magnetic cobalt-iron coating. The magnetic coating is patterned into stripes on microshutters so that shutters can respond to an external magnetic field for the magnetic actuation. A set of column electrodes is placed on top of shutters, and a set of row electrodes on sidewalls is underneath the shutters so that they can be electrostatically latched open. A linear permanent magnet is aligned with the shutter rows and is positioned above a flipped upside-down array, and sweeps across the array in a direction parallel to shutter columns. As the magnet sweeps across the array, sequential rows of shutters are rotated from their natural horizontal orientation to a vertical open position, where they approach vertical electrodes on the sidewalls. When the electrodes are biased with a sufficient electrostatic force to overcome the mechanical restoring force of torsion bars, shutters remain latched to vertical electrodes in their open state. When the bias is removed, or is insufficient, the shutters return to their horizontal, closed positions. To release a shutter, both the electrode on the shutter and the one on the back wall where the shutter sits are grounded. The shutters with one or both ungrounded electrodes are held open. Sub-micron bumps underneath light shields and silicon ribs on back walls are the two features to prevent stiction. These features ensure that the microshutter array functions properly in mechanical motions. The MSA technology can be used primarily in multi-object imaging and spectroscopy, photomask generation, light switches, and in the stepper equipment used to make integrated circuits and MEMS (microelectromechanical systems) devices.

Advanced optical components for next-generation photonic networks

NASA Astrophysics Data System (ADS)

Yoo, S. J. B.

2003-08-01

Future networks will require very high throughput, carrying dominantly data-centric traffic. The role of Photonic Networks employing all-optical systems will become increasingly important in providing scalable bandwidth, agile reconfigurability, and low-power consumptions in the future. In particular, the self-similar nature of data traffic indicates that packet switching and burst switching will be beneficial in the Next Generation Photonic Networks. While the natural conclusion is to pursue Photonic Packet Switching and Photonic Burst Switching systems, there are significant challenges in realizing such a system due to practical limitations in optical component technologies. Lack of a viable all-optical memory technology will continue to drive us towards exploring rapid reconfigurability in the wavelength domain. We will introduce and discuss the advanced optical component technologies behind the Photonic Packet Routing system designed and demonstrated at UC Davis. The system is capable of packet switching and burst switching, as well as circuit switching with 600 psec switching speed and scalability to 42 petabit/sec aggregated switching capacity. By utilizing a combination of rapidly tunable wavelength conversion and a uniform-loss cyclic frequency (ULCF) arrayed waveguide grating router (AWGR), the system is capable of rapidly switching the packets in wavelength, time, and space domains. The label swapping module inside the Photonic Packet Routing system containing a Mach-Zehnder wavelength converter and a narrow-band fiber Bragg-grating achieves all-optical label swapping with optical 2R (potentially 3R) regeneration while maintaining optical transparency for the data payload. By utilizing the advanced optical component technologies, the Photonic Packet Routing system successfully demonstrated error-free, cascaded, multi-hop photonic packet switching and routing with optical-label swapping. This paper will review the advanced optical component technologies and their role in the Next Generation Photonic Networks.

Nanotechnology: MEMS and NEMS and their applications to smart systems and devices

NASA Astrophysics Data System (ADS)

Varadan, Vijay K.

2003-10-01

The microelectronics industry has seen explosive growth during the last thirty years. Extremely large markets for logic and memory devices have driven the development of new materials, and technologies for the fabrication of even more complex devices with features sizes now down at the sub micron and nanometer level. Recent interest has arisen in employing these materials, tools and technologies for the fabrication of miniature sensors and actuators and their integration with electronic circuits to produce smart devices and systems. This effort offers the promise of: (1) increasing the performance and manufacturability of both sensors and actuators by exploiting new batch fabrication processes developed including micro stereo lithographic and micro molding techniques; (2) developing novel classes of materials and mechanical structures not possible previously, such as diamond like carbon, silicon carbide and carbon nanotubes, micro-turbines and micro-engines; (3) development of technologies for the system level and wafer level integration of micro components at the nanometer precision, such as self-assembly techniques and robotic manipulation; (4) development of control and communication systems for MEMS devices, such as optical and RF wireless, and power delivery systems, etc. A novel composite structure can be tailored by functionalizing carbon nano tubes and chemically bonding them with the polymer matrix e.g. block or graft copolymer, or even cross-linked copolymer, to impart exceptional structural, electronic and surface properties. Bio- and Mechanical-MEMS devices derived from this hybrid composite provide a new avenue for future smart systems. The integration of NEMS (NanoElectroMechanical Systems), MEMS, IDTs (Interdigital Transducers) and required microelectronics and conformal antenna in the multifunctional smart materials and composites results in a smart system suitable for sending and control of a variety functions in automobile, aerospace, marine and civil strutures and food and medical industries. This unique combination of technologies also results in novel conformal sensors that can be remotely sensed by an antenna system with the advantage of no power requirements at the sensor site. This paper provides a brief review of MEMS and NEMS based smart systems for various applications mentioned above. Carbon Nano Tubes (CNT) with their unique structure, have already proven to be valuable in their application as tips for scanning probe microscopy, field emission devices, nanoelectronics, H2-storage, electromagnetic absorbers, ESD, EMI films and coatings and structural composites. For many of these applications, highly purified and functionalized CNT which are compatible with many host polymers are needed. A novel microwave CVD processing technique to meet these requirements has been developed at Penn State Center for the Engineering of Electronic and Acoustic Materials and Devices (CEEAMD). This method enables the production of highly purified carbon nano tubes with variable size (from 5 - 40 nm) at low cost (per gram) and high yield. Whereas, carbon nano tubes synthesized using the laser ablation or arc discharge evaporation method always include impurity due to catalyst or catalyst support. The Penn State research is based on the use of zeolites over other metal/metal oxides in the microwave field for a high production and uniformity of the product. An extended coventional purification method has been employed to purify our products in order to remove left over impurity. A novel composite structure can be tailored by functionalizing carbon nano tubes and chemically bonding them with the polymer matrix e.g. block or graft copolymer, or even cross-linked copolymer, to impart exceptional structural, electronic and surface properties. Bio- and Mechanical-MEMS devices derived from this hybrid composites will be presented.

MEMS- and NEMS-based smart devices and systems

NASA Astrophysics Data System (ADS)

Varadan, Vijay K.

2001-11-01

The microelectronics industry has seen explosive growth during the last thirty years. Extremely large markets for logic and memory devices have driven the development of new materials, and technologies for the fabrication of even more complex devices with features sized now don at the sub micron and nanometer level. Recent interest has arisen in employing these materials, tools and technologies for the fabrication of miniature sensors and actuators and their integration with electronic circuits to produce smart devices and systems. This effort offers the promise of: 1) increasing the performance and manufacturability of both sensors and actuators by exploiting new batch fabrication processes developed including micro stereo lithographic an micro molding techniques; 2) developing novel classes of materials and mechanical structures not possible previously, such as diamond like carbon, silicon carbide and carbon nanotubes, micro-turbines and micro-engines; 3) development of technologies for the system level and wafer level integration of micro components at the nanometer precision, such as self-assembly techniques and robotic manipulation; 4) development of control and communication systems for MEMS devices, such as optical and RF wireless, and power delivery systems, etc. A novel composite structure can be tailored by functionalizing carbon nano tubes and chemically bonding them with the polymer matrix e.g. block or graft copolymer, or even cross-linked copolymer, to impart exceptional structural, electronic and surface properties. Bio- and Mechanical-MEMS devices derived from this hybrid composite provide a new avenue for future smart systems. The integration of NEMS (NanoElectroMechanical Systems), MEMS, IDTs (Interdigital Transducers) and required microelectronics and conformal antenna in the multifunctional smart materials and composites results in a smart system suitable for sensing and control of a variety functions in automobile, aerospace, marine and civil structures and food and medical industries. This unique combination of technologies also results in novel conformal sensors that can be remotely sensed by an antenna system with the advantage of no power requirements at the sensor site. This paper provides a brief review of MEMS and NEMS based smart systems for various applications mentioned above. Carbon Nano Tubes (CNT) with their unique structure, have already proven to be valuable in their application as tips for scanning probe microscopy, field emission devices, nanoelectronics, H2-storage, electromagnetic absorbers, ESD, EMI films and coatings and structural composites. For many of these applications, highly purified and functionalized CNT which are compatible with many host polymers are needed. A novel microwave CVD processing technique to meet these requirements has been developed at Penn State Center for the engineering of Electronic and Acoustic Materials and Devices (CEEAMD). This method enables the production of highly purified carbon nano tubes with variable size (from 5-40 nm) at low cost (per gram) and high yield. Whereas, carbon nano tubes synthesized using the laser ablation or arc discharge evaporation method always include impurity due to catalyst or catalyst support. The Penn State research is based on the use of zeolites over other metal/metal oxides in the microwave field for a high production and uniformity of the product. An extended conventional purification method has been employed to purify our products in order to remove left over impurity. A novel composite structure can be tailored by functionalizing carbon nano tubes and chemically bonding them with the polymer matrix e.g. block or graft copolymer, or even cross- linked copolymer, to impart exceptional structural, electronic and surface properties. Bio- and Mechanical-MEMS devices derived from this hybrid composites will be presented.

Computer Access. Tech Use Guide: Using Computer Technology.

ERIC Educational Resources Information Center

Council for Exceptional Children, Reston, VA. Center for Special Education Technology.

One of nine brief guides for special educators on using computer technology, this guide focuses on access including adaptations in input devices, output devices, and computer interfaces. Low technology devices include "no-technology" devices (usually modifications to existing devices), simple switches, and multiple switches. High technology input…