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Sample records for active pixel cmos

  1. CMOS Active Pixel Sensor Technology and Reliability Characterization Methodology

    NASA Technical Reports Server (NTRS)

    Chen, Yuan; Guertin, Steven M.; Pain, Bedabrata; Kayaii, Sammy

    2006-01-01

    This paper describes the technology, design features and reliability characterization methodology of a CMOS Active Pixel Sensor. Both overall chip reliability and pixel reliability are projected for the imagers.

  2. CMOS Active-Pixel Image Sensor With Simple Floating Gates

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R.; Nakamura, Junichi; Kemeny, Sabrina E.

    1996-01-01

    Experimental complementary metal-oxide/semiconductor (CMOS) active-pixel image sensor integrated circuit features simple floating-gate structure, with metal-oxide/semiconductor field-effect transistor (MOSFET) as active circuit element in each pixel. Provides flexibility of readout modes, no kTC noise, and relatively simple structure suitable for high-density arrays. Features desirable for "smart sensor" applications.

  3. Thin Film on CMOS Active Pixel Sensor for Space Applications

    PubMed Central

    Schulze Spuentrup, Jan Dirk; Burghartz, Joachim N.; Graf, Heinz-Gerd; Harendt, Christine; Hutter, Franz; Nicke, Markus; Schmidt, Uwe; Schubert, Markus; Sterzel, Juergen

    2008-01-01

    A 664 × 664 element Active Pixel image Sensor (APS) with integrated analog signal processing, full frame synchronous shutter and random access for applications in star sensors is presented and discussed. A thick vertical diode array in Thin Film on CMOS (TFC) technology is explored to achieve radiation hardness and maximum fill factor.

  4. Monolithic active pixel sensors (MAPS) in a VLSI CMOS technology

    NASA Astrophysics Data System (ADS)

    Turchetta, R.; French, M.; Manolopoulos, S.; Tyndel, M.; Allport, P.; Bates, R.; O'Shea, V.; Hall, G.; Raymond, M.

    2003-03-01

    Monolithic Active Pixel Sensors (MAPS) designed in a standard VLSI CMOS technology have recently been proposed as a compact pixel detector for the detection of high-energy charged particle in vertex/tracking applications. MAPS, also named CMOS sensors, are already extensively used in visible light applications. With respect to other competing imaging technologies, CMOS sensors have several potential advantages in terms of low cost, low power, lower noise at higher speed, random access of pixels which allows windowing of region of interest, ability to integrate several functions on the same chip. This brings altogether to the concept of 'camera-on-a-chip'. In this paper, we review the use of CMOS sensors for particle physics and we analyse their performances in term of the efficiency (fill factor), signal generation, noise, readout speed and sensor area. In most of high-energy physics applications, data reduction is needed in the sensor at an early stage of the data processing before transfer of the data to tape. Because of the large number of pixels, data reduction is needed on the sensor itself or just outside. This brings in stringent requirements on the temporal noise as well as to the sensor uniformity, expressed as a Fixed Pattern Noise (FPN). A pixel architecture with an additional transistor is proposed. This architecture, coupled to correlated double sampling of the signal will allow cancellation of the two dominant noise sources, namely the reset or kTC noise and the FPN. A prototype has been designed in a standard 0.25 μm CMOS technology. It has also a structure for electrical calibration of the sensor. The prototype is functional and detailed tests are under way.

  5. CMOS VLSI Active-Pixel Sensor for Tracking

    NASA Technical Reports Server (NTRS)

    Pain, Bedabrata; Sun, Chao; Yang, Guang; Heynssens, Julie

    2004-01-01

    An architecture for a proposed active-pixel sensor (APS) and a design to implement the architecture in a complementary metal oxide semiconductor (CMOS) very-large-scale integrated (VLSI) circuit provide for some advanced features that are expected to be especially desirable for tracking pointlike features of stars. The architecture would also make this APS suitable for robotic- vision and general pointing and tracking applications. CMOS imagers in general are well suited for pointing and tracking because they can be configured for random access to selected pixels and to provide readout from windows of interest within their fields of view. However, until now, the architectures of CMOS imagers have not supported multiwindow operation or low-noise data collection. Moreover, smearing and motion artifacts in collected images have made prior CMOS imagers unsuitable for tracking applications. The proposed CMOS imager (see figure) would include an array of 1,024 by 1,024 pixels containing high-performance photodiode-based APS circuitry. The pixel pitch would be 9 m. The operations of the pixel circuits would be sequenced and otherwise controlled by an on-chip timing and control block, which would enable the collection of image data, during a single frame period, from either the full frame (that is, all 1,024 1,024 pixels) or from within as many as 8 different arbitrarily placed windows as large as 8 by 8 pixels each. A typical prior CMOS APS operates in a row-at-a-time ( grolling-shutter h) readout mode, which gives rise to exposure skew. In contrast, the proposed APS would operate in a sample-first/readlater mode, suppressing rolling-shutter effects. In this mode, the analog readout signals from the pixels corresponding to the windows of the interest (which windows, in the star-tracking application, would presumably contain guide stars) would be sampled rapidly by routing them through a programmable diagonal switch array to an on-chip parallel analog memory array. The

  6. CMOS Monolithic Active Pixel Sensors (MAPS): Developments and future outlook

    NASA Astrophysics Data System (ADS)

    Turchetta, R.; Fant, A.; Gasiorek, P.; Esbrand, C.; Griffiths, J. A.; Metaxas, M. G.; Royle, G. J.; Speller, R.; Venanzi, C.; van der Stelt, P. F.; Verheij, H.; Li, G.; Theodoridis, S.; Georgiou, H.; Cavouras, D.; Hall, G.; Noy, M.; Jones, J.; Leaver, J.; Machin, D.; Greenwood, S.; Khaleeq, M.; Schulerud, H.; Østby, J. M.; Triantis, F.; Asimidis, A.; Bolanakis, D.; Manthos, N.; Longo, R.; Bergamaschi, A.

    2007-12-01

    Re-invented in the early 1990s, on both sides of the Atlantic, Monolithic Active Pixel Sensors (MAPS) in a CMOS technology are today the most sold solid-state imaging devices, overtaking the traditional technology of Charge-Coupled Devices (CCD). The slow uptake of CMOS MAPS started with low-end applications, for example web-cams, and is slowly pervading the high-end applications, for example in prosumer digital cameras. Higher specifications are required for scientific applications: very low noise, high speed, high dynamic range, large format and radiation hardness are some of these requirements. This paper will present a brief overview of the CMOS Image Sensor technology and of the requirements for scientific applications. As an example, a sensor for X-ray imaging will be presented. This sensor was developed within a European FP6 Consortium, intelligent imaging sensors (I-ImaS).

  7. A CMOS active pixel sensor for retinal stimulation

    NASA Astrophysics Data System (ADS)

    Prydderch, Mark L.; French, Marcus J.; Mathieson, Keith; Adams, Christopher; Gunning, Deborah; Laudanski, Jonathan; Morrison, James D.; Moodie, Alan R.; Sinclair, James

    2006-02-01

    Degenerative photoreceptor diseases, such as age-related macular degeneration and retinitis pigmentosa, are the most common causes of blindness in the western world. A potential cure is to use a microelectronic retinal prosthesis to provide electrical stimulation to the remaining healthy retinal cells. We describe a prototype CMOS Active Pixel Sensor capable of detecting a visual scene and translating it into a train of electrical pulses for stimulation of the retina. The sensor consists of a 10 x 10 array of 100 micron square pixels fabricated on a 0.35 micron CMOS process. Light incident upon each pixel is converted into output current pulse trains with a frequency related to the light intensity. These outputs are connected to a biocompatible microelectrode array for contact to the retinal cells. The flexible design allows experimentation with signal amplitudes and frequencies in order to determine the most appropriate stimulus for the retina. Neural processing in the retina can be studied by using the sensor in conjunction with a Field Programmable Gate Array (FPGA) programmed to behave as a neural network. The sensor has been integrated into a test system designed for studying retinal response. We present the most recent results obtained from this sensor.

  8. A 128 x 128 CMOS Active Pixel Image Sensor for Highly Integrated Imaging Systems

    NASA Technical Reports Server (NTRS)

    Mendis, Sunetra K.; Kemeny, Sabrina E.; Fossum, Eric R.

    1993-01-01

    A new CMOS-based image sensor that is intrinsically compatible with on-chip CMOS circuitry is reported. The new CMOS active pixel image sensor achieves low noise, high sensitivity, X-Y addressability, and has simple timing requirements. The image sensor was fabricated using a 2 micrometer p-well CMOS process, and consists of a 128 x 128 array of 40 micrometer x 40 micrometer pixels. The CMOS image sensor technology enables highly integrated smart image sensors, and makes the design, incorporation and fabrication of such sensors widely accessible to the integrated circuit community.

  9. CMOS Active Pixel Sensor Star Tracker with Regional Electronic Shutter

    NASA Technical Reports Server (NTRS)

    Yadid-Pecht, Orly; Pain, Bedabrata; Staller, Craig; Clark, Christopher; Fossum, Eric

    1996-01-01

    The guidance system in a spacecraft determines spacecraft attitude by matching an observed star field to a star catalog....An APS(active pixel sensor)-based system can reduce mass and power consumption and radiation effects compared to a CCD(charge-coupled device)-based system...This paper reports an APS (active pixel sensor) with locally variable times, achieved through individual pixel reset (IPR).

  10. Development of radiation hard CMOS active pixel sensors for HL-LHC

    NASA Astrophysics Data System (ADS)

    Pernegger, Heinz

    2016-07-01

    New pixel detectors, based on commercial high voltage and/or high resistivity full CMOS processes, hold promise as next-generation active pixel sensors for inner and intermediate layers of the upgraded ATLAS tracker. The use of commercial CMOS processes allow cost-effective detector construction and simpler hybridisation techniques. The paper gives an overview of the results obtained on AMS-produced CMOS sensors coupled to the ATLAS Pixel FE-I4 readout chips. The SOI (silicon-on-insulator) produced sensors by XFAB hold great promise as radiation hard SOI-CMOS sensors due to their combination of partially depleted SOI transistors reducing back-gate effects. The test results include pre-/post-irradiation comparison, measurements of charge collection regions as well as test beam results.

  11. Application-specific architectures of CMOS monolithic active pixel sensors

    NASA Astrophysics Data System (ADS)

    Szelezniak, Michal; Besson, Auguste; Claus, Gilles; Colledani, Claude; Degerli, Yavuz; Deptuch, Grzegorz; Deveaux, Michael; Dorokhov, Andrei; Dulinski, Wojciech; Fourches, Nicolas; Goffe, Mathieu; Grandjean, Damien; Guilloux, Fabrice; Heini, Sebastien; Himmi, Abdelkader; Hu, Christine; Jaaskelainen, Kimmo; Li, Yan; Lutz, Pierre; Orsini, Fabienne; Pellicioli, Michel; Shabetai, Alexandre; Valin, Isabelle; Winter, Marc

    2006-11-01

    Several development directions intended to adapt and optimize monolithic active pixel sensors for specific applications are presented in this work. The first example, compatible with the STAR microvertex upgrade, is based on a simple two-transistor pixel circuitry. It is suited for a long integration time, room-temperature operation and minimum power dissipation. In another approach for this application, a specific readout method is proposed, allowing optimization of the integration time independently of the full frame-readout time. The circuit consists of an in-pixel front-end voltage amplifier, with a gain on the order of five, followed by two analog memory cells. The extended version of this scheme, based on the implementation of more memory cells per pixel, is the solution considered for the outer layers of a microvertex detector at the international linear collider. For the two innermost layers, a circuit allowing fast frame scans together with on-line, on-chip data sparsification is proposed. The first results of this prototype demonstrate that the fixed pattern dispersion is reduced below a noise level of 15 e -, allowing the use of a single comparator or a low-resolution ADC per pixel column. A common element for most of the mentioned readout schemes is a low-noise, low power consumption, layout efficient in-pixel amplifier. A review of possible solutions for this element together with some experimental results is presented.

  12. Analysis of noise characteristics for the active pixels in CMOS image sensors for X-ray imaging

    NASA Astrophysics Data System (ADS)

    Kim, Young Soo; Cho, Gyuseong; Bae, Jun-Hyung

    2006-09-01

    CMOS image sensors have poorer performance compared to conventional charge coupled devices (CCDs). Since CMOS Active Pixel Sensors (APSs) in general have higher temporal noise, higher dark current, smaller full well charge capacitance, and lower spectral response, they cannot provide the same wide dynamic range and superior signal to noise ratio as CCDs. In view of electronic noise, the main source for the CMOS APS is the pixel, along with other signal processing blocks such as row and column decoder, analog signal processor (ASP), analog-to-digital converter (ADC), and timing and control logic circuitry. Therefore, it is important and necessary to characterize noise of the active pixels in CMOS APSs, and we performed experimental measurements and comparisons with theoretical estimations. To derive noise source of the pixels, we designed and fabricated four types of CMOS active pixels, and each pixel is composed of a photodiode and three MOS transistors. The size of these pixels is 100 μm×100 μm. The test chip was fabricated using ETRI 0.8 μm (2P/2M) standard CMOS process. It was found that the dominant noise in CMOS active pixels is shot noise during integration under normal operating conditions. And, it was also seen that epitaxial type pixels have similar noise level compared to non-epitaxial type, and the noise of diffusion type pixel is larger than for a well type pixel on the same substrate type.

  13. A CMOS Active Pixel Sensor for Charged Particle Detection

    SciTech Connect

    Matis, Howard S.; Bieser, Fred; Kleinfelder, Stuart; Rai, Gulshan; Retiere, Fabrice; Ritter, Hans George; Singh, Kunal; Wurzel, Samuel E.; Wieman, Howard; Yamamoto, Eugene

    2002-12-02

    Active Pixel Sensor (APS) technology has shown promise for next-generation vertex detectors. This paper discusses the design and testing of two generations of APS chips. Both are arrays of 128 by 128 pixels, each 20 by 20 {micro}m. Each array is divided into sub-arrays in which different sensor structures (4 in the first version and 16 in the second) and/or readout circuits are employed. Measurements of several of these structures under Fe{sup 55} exposure are reported. The sensors have also been irradiated by 55 MeV protons to test for radiation damage. The radiation increased the noise and reduced the signal. The noise can be explained by shot noise from the increased leakage current and the reduction in signal is due to charge being trapped in the epi layer. Nevertheless, the radiation effect is small for the expected exposures at RHIC and RHIC II. Finally, we describe our concept for mechanically supporting a thin silicon wafer in an actual detector.

  14. Low Power Camera-on-a-Chip Using CMOS Active Pixel Sensor Technology

    NASA Technical Reports Server (NTRS)

    Fossum, E. R.

    1995-01-01

    A second generation image sensor technology has been developed at the NASA Jet Propulsion Laboratory as a result of the continuing need to miniaturize space science imaging instruments. Implemented using standard CMOS, the active pixel sensor (APS) technology permits the integration of the detector array with on-chip timing, control and signal chain electronics, including analog-to-digital conversion.

  15. Integrated imaging sensor systems with CMOS active pixel sensor technology

    NASA Technical Reports Server (NTRS)

    Yang, G.; Cunningham, T.; Ortiz, M.; Heynssens, J.; Sun, C.; Hancock, B.; Seshadri, S.; Wrigley, C.; McCarty, K.; Pain, B.

    2002-01-01

    This paper discusses common approaches to CMOS APS technology, as well as specific results on the five-wire programmable digital camera-on-a-chip developed at JPL. The paper also reports recent research in the design, operation, and performance of APS imagers for several imager applications.

  16. Proof of principle study of the use of a CMOS active pixel sensor for proton radiography

    SciTech Connect

    Seco, Joao; Depauw, Nicolas

    2011-02-15

    Purpose: Proof of principle study of the use of a CMOS active pixel sensor (APS) in producing proton radiographic images using the proton beam at the Massachusetts General Hospital (MGH). Methods: A CMOS APS, previously tested for use in s-ray radiation therapy applications, was used for proton beam radiographic imaging at the MGH. Two different setups were used as a proof of principle that CMOS can be used as proton imaging device: (i) a pen with two metal screws to assess spatial resolution of the CMOS and (ii) a phantom with lung tissue, bone tissue, and water to assess tissue contrast of the CMOS. The sensor was then traversed by a double scattered monoenergetic proton beam at 117 MeV, and the energy deposition inside the detector was recorded to assess its energy response. Conventional x-ray images with similar setup at voltages of 70 kVp and proton images using commercial Gafchromic EBT 2 and Kodak X-Omat V films were also taken for comparison purposes. Results: Images were successfully acquired and compared to x-ray kVp and proton EBT2/X-Omat film images. The spatial resolution of the CMOS detector image is subjectively comparable to the EBT2 and Kodak X-Omat V film images obtained at the same object-detector distance. X-rays have apparent higher spatial resolution than the CMOS. However, further studies with different commercial films using proton beam irradiation demonstrate that the distance of the detector to the object is important to the amount of proton scatter contributing to the proton image. Proton images obtained with films at different distances from the source indicate that proton scatter significantly affects the CMOS image quality. Conclusion: Proton radiographic images were successfully acquired at MGH using a CMOS active pixel sensor detector. The CMOS demonstrated spatial resolution subjectively comparable to films at the same object-detector distance. Further work will be done in order to establish the spatial and energy resolution of the

  17. A CMOS Energy Harvesting and Imaging (EHI) Active Pixel Sensor (APS) Imager for Retinal Prosthesis.

    PubMed

    Ay, S U

    2011-12-01

    A CMOS image sensor capable of imaging and energy harvesting on same focal plane is presented for retinal prosthesis. The energy harvesting and imaging (EHI) active pixel sensor (APS) imager was designed, fabricated, and tested in a standard 0.5 μm CMOS process. It has 54 × 50 array of 21 × 21 μm(2) EHI pixels, 10-bit supply boosted (SB) SAR ADC, and charge pump circuits consuming only 14.25 μW from 1.2 V and running at 7.4 frames per second. The supply boosting technique (SBT) is used in an analog signal chain of the EHI imager. Harvested solar energy on focal plane is stored on an off-chip capacitor with the help of a charge pump circuit with better than 70% efficiency. Energy harvesting efficiency of the EHI pixel was measured at different light levels. It was 9.4% while producing 0.41 V open circuit voltage. The EHI imager delivers 3.35 μW of power was delivered to a resistive load at maximum power point operation. The measured pixel array figure of merit (FoM) was 1.32 pW/frame/pixel while imager figure of merit (iFoM) including whole chip power consumption was 696 fJ/pixel/code for the EHI imager. PMID:23852551

  18. Performance of a novel wafer scale CMOS active pixel sensor for bio-medical imaging.

    PubMed

    Esposito, M; Anaxagoras, T; Konstantinidis, A C; Zheng, Y; Speller, R D; Evans, P M; Allinson, N M; Wells, K

    2014-07-01

    Recently CMOS active pixels sensors (APSs) have become a valuable alternative to amorphous silicon and selenium flat panel imagers (FPIs) in bio-medical imaging applications. CMOS APSs can now be scaled up to the standard 20 cm diameter wafer size by means of a reticle stitching block process. However, despite wafer scale CMOS APS being monolithic, sources of non-uniformity of response and regional variations can persist representing a significant challenge for wafer scale sensor response. Non-uniformity of stitched sensors can arise from a number of factors related to the manufacturing process, including variation of amplification, variation between readout components, wafer defects and process variations across the wafer due to manufacturing processes. This paper reports on an investigation into the spatial non-uniformity and regional variations of a wafer scale stitched CMOS APS. For the first time a per-pixel analysis of the electro-optical performance of a wafer CMOS APS is presented, to address inhomogeneity issues arising from the stitching techniques used to manufacture wafer scale sensors. A complete model of the signal generation in the pixel array has been provided and proved capable of accounting for noise and gain variations across the pixel array. This novel analysis leads to readout noise and conversion gain being evaluated at pixel level, stitching block level and in regions of interest, resulting in a coefficient of variation ⩽1.9%. The uniformity of the image quality performance has been further investigated in a typical x-ray application, i.e. mammography, showing a uniformity in terms of CNR among the highest when compared with mammography detectors commonly used in clinical practice. Finally, in order to compare the detection capability of this novel APS with the technology currently used (i.e. FPIs), theoretical evaluation of the detection quantum efficiency (DQE) at zero-frequency has been performed, resulting in a higher DQE for this

  19. Performance of a novel wafer scale CMOS active pixel sensor for bio-medical imaging

    NASA Astrophysics Data System (ADS)

    Esposito, M.; Anaxagoras, T.; Konstantinidis, A. C.; Zheng, Y.; Speller, R. D.; Evans, P. M.; Allinson, N. M.; Wells, K.

    2014-07-01

    Recently CMOS active pixels sensors (APSs) have become a valuable alternative to amorphous silicon and selenium flat panel imagers (FPIs) in bio-medical imaging applications. CMOS APSs can now be scaled up to the standard 20 cm diameter wafer size by means of a reticle stitching block process. However, despite wafer scale CMOS APS being monolithic, sources of non-uniformity of response and regional variations can persist representing a significant challenge for wafer scale sensor response. Non-uniformity of stitched sensors can arise from a number of factors related to the manufacturing process, including variation of amplification, variation between readout components, wafer defects and process variations across the wafer due to manufacturing processes. This paper reports on an investigation into the spatial non-uniformity and regional variations of a wafer scale stitched CMOS APS. For the first time a per-pixel analysis of the electro-optical performance of a wafer CMOS APS is presented, to address inhomogeneity issues arising from the stitching techniques used to manufacture wafer scale sensors. A complete model of the signal generation in the pixel array has been provided and proved capable of accounting for noise and gain variations across the pixel array. This novel analysis leads to readout noise and conversion gain being evaluated at pixel level, stitching block level and in regions of interest, resulting in a coefficient of variation ⩽1.9%. The uniformity of the image quality performance has been further investigated in a typical x-ray application, i.e. mammography, showing a uniformity in terms of CNR among the highest when compared with mammography detectors commonly used in clinical practice. Finally, in order to compare the detection capability of this novel APS with the technology currently used (i.e. FPIs), theoretical evaluation of the detection quantum efficiency (DQE) at zero-frequency has been performed, resulting in a higher DQE for this

  20. CMOS Active Pixel Sensors as energy-range detectors for proton Computed Tomography

    NASA Astrophysics Data System (ADS)

    Esposito, M.; Anaxagoras, T.; Evans, P. M.; Green, S.; Manolopoulos, S.; Nieto-Camero, J.; Parker, D. J.; Poludniowski, G.; Price, T.; Waltham, C.; Allinson, N. M.

    2015-06-01

    Since the first proof of concept in the early 70s, a number of technologies has been proposed to perform proton CT (pCT), as a means of mapping tissue stopping power for accurate treatment planning in proton therapy. Previous prototypes of energy-range detectors for pCT have been mainly based on the use of scintillator-based calorimeters, to measure proton residual energy after passing through the patient. However, such an approach is limited by the need for only a single proton passing through the energy-range detector in a read-out cycle. A novel approach to this problem could be the use of pixelated detectors, where the independent read-out of each pixel allows to measure simultaneously the residual energy of a number of protons in the same read-out cycle, facilitating a faster and more efficient pCT scan. This paper investigates the suitability of CMOS Active Pixel Sensors (APSs) to track individual protons as they go through a number of CMOS layers, forming an energy-range telescope. Measurements performed at the iThemba Laboratories will be presented and analysed in terms of correlation, to confirm capability of proton tracking for CMOS APSs.

  1. Depleted Monolithic Active Pixel Sensors (DMAPS) implemented in LF-150 nm CMOS technology

    NASA Astrophysics Data System (ADS)

    Kishishita, T.; Hemperek, T.; Krüger, H.; Wermes, N.

    2015-03-01

    We present the recent development of Depleted Monolithic Active Pixel Sensors (DMAPS), implemented with an LFoundry (LF) 150 nm CMOS process. MAPS detectors based on an epi-layer have been matured in recent years and have attractive features in terms of reducing material budget and handling cost compared to conventional hybrid pixel detectors. However, the obtained signal is relatively small (~1000 e-) due to the thin epi-layer, and charge collection time is relatively slow, e.g., in the order of 100 ns, because charges are mainly collected by diffusion. Modern commercial CMOS technology, however, offers advanced process options to overcome such difficulties and enable truly monolithic devices as an alternative to hybrid pixel sensors and charge coupled devices. Unlike in the case of the standard MAPS technologies with epi-layers, the LF process provides a high-resistivity substrate that enables large signal and fast charge collection by drift in a ~50 μm thick depleted layer. Since this process also enables the use of deep n- and p-wells to isolate the collection electrode from the thin active device layer, PMOS and NMOS transistors are available for the readout electronics in each pixel cell. In order to evaluate the sensor and transistor characteristics, several collection electrodes variants and readout architectures have been implemented. In this report, we focus on its design aspect of the LF-DMAPS prototype chip.

  2. A 512×512 CMOS Monolithic Active Pixel Sensor with integrated ADCs for space science

    NASA Astrophysics Data System (ADS)

    Prydderch, M. L.; Waltham, N. J.; Turchetta, R.; French, M. J.; Holt, R.; Marshall, A.; Burt, D.; Bell, R.; Pool, P.; Eyles, C.; Mapson-Menard, H.

    2003-10-01

    In the last few years, CMOS sensors have become widely used for consumer applications, but little has been done for scientific instruments. In this paper we present the design and experimental characterisation of a Monolithic Active Pixel Sensor (MAPS) intended for a space science application. The sensor incorporates a 525×525 array of pixels on a 25 μm pitch. Each pixel contains a detector together with three transistors that are used for pixel reset, pixel selection and charge-to-voltage conversion. The detector consists of four n-well/p-substrate diodes combining optimum charge collection and low noise performance. The array readout is column-parallel with adjustable gain column amplifiers and a 10-bit single slope ADC. Data conversion takes place simultaneously for all the 525 pixels in one row. The ADC slope can be adjusted in order to give the best dynamic range for a given brightness of a scene. The digitised data are output on a 10-bit bus at 3 MHz. An on-chip state machine generates all of the control signals needed for the readout. All of the bias currents and voltages are generated on chip by a DAC that is programmable through an I 2C compatible interface. The sensor was designed and fabricated on a standard 0.5 μm CMOS technology. The overall die size is 16.7 mm×19.9 mm including the associated readout electronics and bond pads. Preliminary test results show that the full-scale design works well, meeting the Star Tracker requirements with less than 1-bit noise, good linearity and good optical performance.

  3. Photon small-field measurements with a CMOS active pixel sensor.

    PubMed

    Spang, F Jiménez; Rosenberg, I; Hedin, E; Royle, G

    2015-06-01

    In this work the dosimetric performance of CMOS active pixel sensors for the measurement of small photon beams is presented. The detector used consisted of an array of 520  × 520 pixels on a 25 µm pitch. Dosimetric parameters measured with this sensor were compared with data collected with an ionization chamber, a film detector and GEANT4 Monte Carlo simulations. The sensor performance for beam profiles measurements was evaluated for field sizes of 0.5  × 0.5 cm(2). The high spatial resolution achieved with this sensor allowed the accurate measurement of profiles, beam penumbrae and field size under lateral electronic disequilibrium. Field size and penumbrae agreed within 5.4% and 2.2% respectively with film measurements. Agreements with ionization chambers better than 1.0% were obtained when measuring tissue-phantom ratios. Output factor measurements were in good agreement with ionization chamber and Monte Carlo simulation. The data obtained from this imaging sensor can be easily analyzed to extract dosimetric information. The results presented in this work are promising for the development and implementation of CMOS active pixel sensors for dosimetry applications. PMID:25985207

  4. Photon small-field measurements with a CMOS active pixel sensor

    NASA Astrophysics Data System (ADS)

    Jiménez Spang, F.; Rosenberg, I.; Hedin, E.; Royle, G.

    2015-06-01

    In this work the dosimetric performance of CMOS active pixel sensors for the measurement of small photon beams is presented. The detector used consisted of an array of 520  × 520 pixels on a 25 µm pitch. Dosimetric parameters measured with this sensor were compared with data collected with an ionization chamber, a film detector and GEANT4 Monte Carlo simulations. The sensor performance for beam profiles measurements was evaluated for field sizes of 0.5  × 0.5 cm2. The high spatial resolution achieved with this sensor allowed the accurate measurement of profiles, beam penumbrae and field size under lateral electronic disequilibrium. Field size and penumbrae agreed within 5.4% and 2.2% respectively with film measurements. Agreements with ionization chambers better than 1.0% were obtained when measuring tissue-phantom ratios. Output factor measurements were in good agreement with ionization chamber and Monte Carlo simulation. The data obtained from this imaging sensor can be easily analyzed to extract dosimetric information. The results presented in this work are promising for the development and implementation of CMOS active pixel sensors for dosimetry applications.

  5. Development of CMOS Active Pixel Image Sensors for Low Cost Commercial Applications

    NASA Technical Reports Server (NTRS)

    Fossum, E.; Gee, R.; Kemeny, S.; Kim, Q.; Mendis, S.; Nakamura, J.; Nixon, R.; Ortiz, M.; Pain, B.; Zhou, Z.; Ackland, B.; Dickinson, A.; Eid, E.; Inglis, D.

    1994-01-01

    This paper describes ongoing research and development of CMOS active pixel image sensors for low cost commercial applications. A number of sensor designs have been fabricated and tested in both p-well and n-well technologies. Major elements in the development of the sensor include on-chip analog signal processing circuits for the reduction of fixed pattern noise, on-chip timing and control circuits and on-chip analog-to-digital conversion (ADC). Recent results and continuing efforts in these areas will be presented.

  6. Characterisation of a CMOS active pixel sensor for use in the TEAM microscope

    NASA Astrophysics Data System (ADS)

    Battaglia, Marco; Contarato, Devis; Denes, Peter; Doering, Dionisio; Duden, Thomas; Krieger, Brad; Giubilato, Piero; Gnani, Dario; Radmilovic, Velimir

    2010-10-01

    A 1M- and a 4M-pixel monolithic CMOS active pixel sensor with 9.5×9.5 μm2 pixels have been developed for direct imaging in transmission electron microscopy as part of the TEAM project. We present the design and a full characterisation of the detector. Data collected with electron beams at various energies of interest in electron microscopy are used to determine the detector response. Data are compared to predictions of simulation. The line spread function measured with 80 and 300 keV electrons is (12.1±0.7) and (7.4±0.6) μm, respectively, in good agreement with our simulation. We measure the detection quantum efficiency to be 0.78±0.04 at 80 keV and 0.74±0.03 at 300 keV. Using a new imaging technique, based on single electron reconstruction, the line spread function for 80 and 300 keV electrons becomes (6.7±0.3) and (2.4±0.2) μm, respectively. The radiation tolerance of the pixels has been tested up to 5 Mrad and the detector is still functional with a decrease of dynamic range by ≃30%, corresponding to a reduction in full-well depth from ˜39 to ˜27 primary 300 keV electrons, due to leakage current increase, but identical line spread function performance.

  7. 12-inch-wafer-scale CMOS active-pixel sensor for digital mammography

    NASA Astrophysics Data System (ADS)

    Heo, Sung Kyn; Kosonen, Jari; Hwang, Sung Ha; Kim, Tae Woo; Yun, Seungman; Kim, Ho Kyung

    2011-03-01

    This paper describes the development of an active-pixel sensor (APS) panel, which has a field-of-view of 23.1×17.1 cm and features 70-μm-sized pixels arranged in a 3300×2442 array format, for digital mammographic applications. The APS panel was realized on 12-inch wafers based on the standard complementary metal-oxide-semiconductor (CMOS) technology without physical tiling processes of several small-area sensor arrays. Electrical performance of the developed panel is described in terms of dark current, full-well capacity and leakage current map. For mammographic imaging, the optimized CsI:Tl scintillator is experimentally determined by being combined with the developed panel and analyzing im aging characteristics, such as modulation-transfer function, noise-power spectrum, detective quantum efficiency, image l ag, and contrast-detail analysis by using the CDMAM 3.4 phantom. With these results, we suggest that the developed CMOS-based detector can be used for conventional and advanced digital mammographic applications.

  8. CMOS digital pixel sensors: technology and applications

    NASA Astrophysics Data System (ADS)

    Skorka, Orit; Joseph, Dileepan

    2014-04-01

    CMOS active pixel sensor technology, which is widely used these days for digital imaging, is based on analog pixels. Transition to digital pixel sensors can boost signal-to-noise ratios and enhance image quality, but can increase pixel area to dimensions that are impractical for the high-volume market of consumer electronic devices. There are two main approaches to digital pixel design. The first uses digitization methods that largely rely on photodetector properties and so are unique to imaging. The second is based on adaptation of a classical analog-to-digital converter (ADC) for in-pixel data conversion. Imaging systems for medical, industrial, and security applications are emerging lower-volume markets that can benefit from these in-pixel ADCs. With these applications, larger pixels are typically acceptable, and imaging may be done in invisible spectral bands.

  9. Improved Design of Active Pixel CMOS Sensors for Charged Particle Detection

    SciTech Connect

    Deptuch, Grzegorz

    2007-11-12

    The Department of Energy (DOE) nuclear physics program requires developments in detector instrumentation electronics with improved energy, position and timing resolution, sensitivity, rate capability, stability, dynamic range, and background suppression. The current Phase-I project was focused on analysis of standard-CMOS photogate Active Pixel Sensors (APS) as an efficient solution to this challenge. The advantages of the CMOS APS over traditional hybrid approaches (i.e., separate detection regions bump-bonded to readout circuits) include greatly reduced cost, low power and the potential for vastly larger pixel counts and densities. However, challenges remain in terms of the signal-to-noise ratio (SNR) and readout speed (currently on the order of milliseconds), which is the major problem for this technology. Recent work has shown that the long readout time for photogate APS is due to the presence of (interface) traps at the semiconductor-oxide interface. This Phase-I work yielded useful results in two areas: (a) Advanced three-dimensional (3D) physics-based simulation models and simulation-based analysis of the impact of interface trap density on the transient charge collection characteristics of existing APS structures; and (b) Preliminary analysis of the feasibility of an improved photogate pixel structure (i.e., new APS design) with an induced electric field under the charge collecting electrode to enhance charge collection. Significant effort was dedicated in Phase-I to the critical task of implementing accurate interface trap models in CFDRC's NanoTCAD 3D semiconductor device-physics simulator. This resulted in validation of the new NanoTCAD models and simulation results against experimental (published) data, within the margin of uncertainty associated with obtaining device geometry, material properties, and experimentation details. Analyses of the new, proposed photogate APS design demonstrated several promising trends.

  10. Characterization of Depleted Monolithic Active Pixel detectors implemented with a high-resistive CMOS technology

    NASA Astrophysics Data System (ADS)

    Kishishita, T.; Hemperek, T.; Rymaszewski, P.; Hirono, T.; Krüger, H.; Wermes, N.

    2016-07-01

    We present the recent development of DMAPS (Depleted Monolithic Active Pixel Sensor), implemented with a Toshiba 130 nm CMOS process. Unlike in the case of standard MAPS technologies which are based on an epi-layer, this process provides a high-resistive substrate that enables larger signal and faster charge collection by drift in a 50 - 300 μm thick depleted layer. Since this process also enables the use of deep n-wells to isolate the collection electrodes from the thin active device layer, NMOS and PMOS transistors are available for the readout electronics in each pixel cell. In order to characterize the technology, we implemented a simple three transistor readout with a variety of pixel pitches and input FET sizes. This layout variety gives us a clue on sensor characteristics for future optimization, such as the input detector capacitance or leakage current. In the initial measurement, the radiation spectra were obtained from 55Fe with an energy resolution of 770 eV (FWHM) and 90Sr with the MVP of 4165 e-.

  11. Physical characterization and performance comparison of active- and passive-pixel CMOS detectors for mammography.

    PubMed

    Elbakri, I A; McIntosh, B J; Rickey, D W

    2009-03-21

    We investigated the physical characteristics of two complementary metal oxide semiconductor (CMOS) mammography detectors. The detectors featured 14-bit image acquisition, 50 microm detector element (del) size and an active area of 5 cm x 5 cm. One detector was a passive-pixel sensor (PPS) with signal amplification performed by an array of amplifiers connected to dels via data lines. The other detector was an active-pixel sensor (APS) with signal amplification performed at each del. Passive-pixel designs have higher read noise due to data line capacitance, and the APS represents an attempt to improve the noise performance of this technology. We evaluated the detectors' resolution by measuring the modulation transfer function (MTF) using a tilted edge. We measured the noise power spectra (NPS) and detective quantum efficiencies (DQE) using mammographic beam conditions specified by the IEC 62220-1-2 standard. Our measurements showed the APS to have much higher gain, slightly higher MTF, and higher NPS. The MTF of both sensors approached 10% near the Nyquist limit. DQE values near dc frequency were in the range of 55-67%, with the APS sensor DQE lower than the PPS DQE for all frequencies. Our results show that lower read noise specifications in this case do not translate into gains in the imaging performance of the sensor. We postulate that the lower fill factor of the APS is a possible cause for this result. PMID:19242050

  12. Pitch dependence of the tolerance of CMOS monolithic active pixel sensors to non-ionizing radiation

    NASA Astrophysics Data System (ADS)

    Doering, D.; Deveaux, M.; Domachowski, M.; Fröhlich, I.; Koziel, M.; Müntz, C.; Scharrer, P.; Stroth, J.

    2013-12-01

    CMOS monolithic active pixel sensors (MAPS) have demonstrated excellent performance as tracking detectors for charged particles. They provide an outstanding spatial resolution (a few μm), a detection efficiency of ≳ 99.9 %, very low material budget (0.05 %X0) and good radiation tolerance (≳ 1 Mrad, ≳1013neq /cm2) (Deveaux et al. [1]). This makes them an interesting technology for various applications in heavy ion and particle physics. Their tolerance to bulk damage was recently improved by using high-resistivity (∼ 1 kΩ cm) epitaxial layers as sensitive volume (Deveaux et al. [1], Dorokhov et al. [2]). The radiation tolerance of conventional MAPS is known to depend on the pixel pitch. This is as a higher pitch extends the distance, which signal electrons have to travel by thermal diffusion before being collected. Increased diffusion paths turn into a higher probability of loosing signal charge due to recombination. Provided that a similar effect exists in MAPS with high-resistivity epitaxial layer, it could be used to extend their radiation tolerance further. We addressed this question with MIMOSA-18AHR prototypes, which were provided by the IPHC Strasbourg and irradiated with reactor neutrons. We report about the results of this study and provide evidences that MAPS with 10 μm pixel pitch tolerate doses of ≳ 3 ×1014neq /cm2.

  13. CMOS Active-Pixel Image Sensor With Intensity-Driven Readout

    NASA Technical Reports Server (NTRS)

    Langenbacher, Harry T.; Fossum, Eric R.; Kemeny, Sabrina

    1996-01-01

    Proposed complementary metal oxide/semiconductor (CMOS) integrated-circuit image sensor automatically provides readouts from pixels in order of decreasing illumination intensity. Sensor operated in integration mode. Particularly useful in number of image-sensing tasks, including diffractive laser range-finding, three-dimensional imaging, event-driven readout of sparse sensor arrays, and star tracking.

  14. Radiation-hard active CMOS pixel sensors for HL-LHC detector upgrades

    NASA Astrophysics Data System (ADS)

    Backhaus, Malte

    2015-02-01

    The luminosity of the Large Hadron Collider (LHC) will be increased during the Long Shutdown of 2022 and 2023 (LS3) in order to increase the sensitivity of its experiments. A completely new inner detector for the ATLAS experiment needs to be developed to withstand the extremely harsh environment of the upgraded, so-called High-Luminosity LHC (HL-LHC). High radiation hardness as well as granularity is mandatory to cope with the requirements in terms of radiation damage as well as particle occupancy. A new silicon detector concept that uses commercial high voltage and/or high resistivity full complementary metal-oxide-semiconductor (CMOS) processes as active sensor for pixel and/or strip layers has risen high attention, because it potentially provides high radiation hardness and granularity and at the same time reduced price due to the commercial processing and possibly relaxed requirements for the hybridization technique. Results on the first prototypes characterized in a variety of laboratory as well as test beam environments are presented.

  15. Advanced monolithic active pixel sensors for tracking, vertexing and calorimetry with full CMOS capability

    NASA Astrophysics Data System (ADS)

    Stanitzki, M.; SPiDeR Collaboration, www. spider. ac. uk

    2011-09-01

    We present test results from the "TPAC" and "F ORTIS" sensors produced using the 180 nm CMOS INMAPS process. The TPAC sensor has a 50 μm pixel size with advanced in-pixel electronics. Although TPAC was developed for digital electromagnetic calorimetry, the technology can be readily extended to tracking and vertexing applications where highly granular pixels with in-pixel intelligence are required. By way of example, a variant of the TPAC sensor has been proposed for the Super B vertex detector. The F ORTIS sensor is a prototype with several pixel variants to study the performance of a four transistors (4T) architecture and is the first sensor of this type tested for particle physics applications. TPAC and F ORTIS sensors have been fabricated with some of the processing innovations available in INMAPS such as deep p-wells and high-resistivity epitaxial layers. The performance of these sensor variants has been measured both in the laboratory and at test beams and results showing significant improvements due to these innovations are presented. We have recently manufactured the "C HERWELL" sensor, building on the experience with both TPAC and F ORTIS and making use of the 4T approach. C HERWELL is designed for tracking and vertexing and has an integrated ADC and targets very low-noise performance. The principal features of C HERWELL are described.

  16. CMOS monolithic pixel sensors research and development at LBNL

    NASA Astrophysics Data System (ADS)

    Contarato, D.; Bussat, J.-M.; Denes, P.; Greiner, L.; Kim, T.; Stezelberger, T.; Wieman, H.; Battaglia, M.; Hooberman, B.; Tompkins, L.

    2007-12-01

    This paper summarizes the recent progress in the design and characterization of CMOS pixel sensors at LBNL. Results of lab tests, beam tests and radiation hardness tests carried out at LBNL on a test structure with pixels of various sizes are reported. The first results of the characterization of back-thinned CMOS pixel sensors are also reported, and future plans and activities are discussed.

  17. Radiation-hard Active Pixel Sensors for HL-LHC Detector Upgrades based on HV-CMOS Technology

    NASA Astrophysics Data System (ADS)

    Miucci, A.; Gonella, L.; Hemperek, T.; Hügging, F.; Krüger, H.; Obermann, T.; Wermes, N.; Garcia-Sciveres, M.; Backhaus, M.; Capeans, M.; Feigl, S.; Nessi, M.; Pernegger, H.; Ristic, B.; Gonzalez-Sevilla, S.; Ferrere, D.; Iacobucci, G.; La Rosa, A.; Muenstermann, D.; George, M.; Große-Knetter, J.; Quadt, A.; Rieger, J.; Weingarten, J.; Bates, R.; Blue, A.; Buttar, C.; Hynds, D.; Kreidl, C.; Peric, I.; Breugnon, P.; Pangaud, P.; Godiot-Basolo, S.; Fougeron, D.; Bompard, F.; Clemens, J. C.; Liu, J.; Barbero, M.; Rozanov, A.; HV-CMOS Collaboration

    2014-05-01

    Luminosity upgrades are discussed for the LHC (HL-LHC) which would make updates to the detectors necessary, requiring in particular new, even more radiation-hard and granular, sensors for the inner detector region. A proposal for the next generation of inner detectors is based on HV-CMOS: a new family of silicon sensors based on commercial high-voltage CMOS technology, which enables the fabrication of part of the pixel electronics inside the silicon substrate itself. The main advantages of this technology with respect to the standard silicon sensor technology are: low material budget, fast charge collection time, high radiation tolerance, low cost and operation at room temperature. A traditional readout chip is still needed to receive and organize the data from the active sensor and to handle high-level functionality such as trigger management. HV-CMOS has been designed to be compatible with both pixel and strip readout. In this paper an overview of HV2FEI4, a HV-CMOS prototype in 180 nm AMS technology, will be given. Preliminary results after neutron and X-ray irradiation are shown.

  18. Integrated X-ray and charged particle active pixel CMOS sensor arrays using an epitaxial silicon sensitive region

    SciTech Connect

    Kleinfelder, Stuart; Bichsel, Hans; Bieser, Fred; Matis, Howard S.; Rai, Gulshan; Retiere, Fabrice; Weiman, Howard; Yamamoto, Eugene

    2002-07-01

    Integrated CMOS Active Pixel Sensor (APS) arrays have been fabricated and tested using X-ray and electron sources. The 128 by 128 pixel arrays, designed in a standard 0.25 micron process, use a {approx}10 micron epitaxial silicon layer as a deep detection region. The epitaxial layer has a much greater thickness than the surface features used by standard CMOS APS, leading to stronger signals and potentially better signal-to-noise ratio (SNR). On the other hand, minority carriers confined within the epitaxial region may diffuse to neighboring pixels, blur images and reduce peak signal intensity. But for low-rate, sparse-event images, centroid analysis of this diffusion may be used to increase position resolution. Careful trade-offs involving pixel size and sense-node area verses capacitance must be made to optimize overall performance. The prototype sensor arrays, therefore, include a range of different pixel designs, including different APS circuits and a range of different epitaxial layer contact structures. The fabricated arrays were tested with 1.5 GeV electrons and Fe-55 X-ray sources, yielding a measured noise of 13 electrons RMS and an SNR for single Fe-55 X-rays of greater than 38.

  19. 50 μm pixel pitch wafer-scale CMOS active pixel sensor x-ray detector for digital breast tomosynthesis

    NASA Astrophysics Data System (ADS)

    Zhao, C.; Konstantinidis, A. C.; Zheng, Y.; Anaxagoras, T.; Speller, R. D.; Kanicki, J.

    2015-12-01

    Wafer-scale CMOS active pixel sensors (APSs) have been developed recently for x-ray imaging applications. The small pixel pitch and low noise are very promising properties for medical imaging applications such as digital breast tomosynthesis (DBT). In this work, we evaluated experimentally and through modeling the imaging properties of a 50 μm pixel pitch CMOS APS x-ray detector named DynAMITe (Dynamic Range Adjustable for Medical Imaging Technology). A modified cascaded system model was developed for CMOS APS x-ray detectors by taking into account the device nonlinear signal and noise properties. The imaging properties such as modulation transfer function (MTF), noise power spectrum (NPS), and detective quantum efficiency (DQE) were extracted from both measurements and the nonlinear cascaded system analysis. The results show that the DynAMITe x-ray detector achieves a high spatial resolution of 10 mm-1 and a DQE of around 0.5 at spatial frequencies  <1 mm-1. In addition, the modeling results were used to calculate the image signal-to-noise ratio (SNRi) of microcalcifications at various mean glandular dose (MGD). For an average breast (5 cm thickness, 50% glandular fraction), 165 μm microcalcifications can be distinguished at a MGD of 27% lower than the clinical value (~1.3 mGy). To detect 100 μm microcalcifications, further optimizations of the CMOS APS x-ray detector, image aquisition geometry and image reconstruction techniques should be considered.

  20. 50 μm pixel pitch wafer-scale CMOS active pixel sensor x-ray detector for digital breast tomosynthesis.

    PubMed

    Zhao, C; Konstantinidis, A C; Zheng, Y; Anaxagoras, T; Speller, R D; Kanicki, J

    2015-12-01

    Wafer-scale CMOS active pixel sensors (APSs) have been developed recently for x-ray imaging applications. The small pixel pitch and low noise are very promising properties for medical imaging applications such as digital breast tomosynthesis (DBT). In this work, we evaluated experimentally and through modeling the imaging properties of a 50 μm pixel pitch CMOS APS x-ray detector named DynAMITe (Dynamic Range Adjustable for Medical Imaging Technology). A modified cascaded system model was developed for CMOS APS x-ray detectors by taking into account the device nonlinear signal and noise properties. The imaging properties such as modulation transfer function (MTF), noise power spectrum (NPS), and detective quantum efficiency (DQE) were extracted from both measurements and the nonlinear cascaded system analysis. The results show that the DynAMITe x-ray detector achieves a high spatial resolution of 10 mm(-1) and a DQE of around 0.5 at spatial frequencies  <1 mm(-1). In addition, the modeling results were used to calculate the image signal-to-noise ratio (SNRi) of microcalcifications at various mean glandular dose (MGD). For an average breast (5 cm thickness, 50% glandular fraction), 165 μm microcalcifications can be distinguished at a MGD of 27% lower than the clinical value (~1.3 mGy). To detect 100 μm microcalcifications, further optimizations of the CMOS APS x-ray detector, image aquisition geometry and image reconstruction techniques should be considered. PMID:26540090

  1. Fourier analysis of the imaging characteristics of a CMOS active pixel detector for mammography by using a linearization method

    NASA Astrophysics Data System (ADS)

    Han, Jong Chul; Yun, Seungman; Youn, Hanbean; Kam, Soohwa; Cho, Seungryong; Achterkirchen, Thorsten G.; Kim, Ho Kyung

    2014-09-01

    Active pixel design using the complementary metal-oxide-semiconductor (CMOS) process is a compelling solution for use in X-ray imaging detectors because of its excellent electronic noise characteristics. We have investigated the imaging performance of a CMOS active pixel photodiode array coupled to a granular phosphor through a fiber-optic faceplate for mammographic applications. The imaging performance included the modulation-transfer function (MTF), noise-power spectrum (NPS), and detective quantum efficiency (DQE). Because we observed a nonlinear detector response at low exposures, we used the linearization method for the analysis of the DQE. The linearization method uses the images obtained at detector input, which are converted from those obtained at detector output by using the inverse of the detector response. Compared to the conventional method, the linearization method provided almost the same MTF and a slightly lower normalized NPS. However, the difference between the DQE results obtained by using the two methods was significant. We claim that the conventional DQE analysis of a detector having a nonlinear response characteristic can yield wrong results. Under the standard mammographic imaging condition, we obtained a DQE performance that was competitive with the performances of conventional flat-panel mammography detectors. We believe that the CMOS detector investigated in this study can be successfully used for mammography.

  2. Non-linear responsivity characterisation of a CMOS Active Pixel Sensor for high resolution imaging of the Jovian system

    NASA Astrophysics Data System (ADS)

    Soman, M.; Stefanov, K.; Weatherill, D.; Holland, A.; Gow, J.; Leese, M.

    2015-02-01

    The Jovian system is the subject of study for the Jupiter Icy Moon Explorer (JUICE), an ESA mission which is planned to launch in 2022. The scientific payload is designed for both characterisation of the magnetosphere and radiation environment local to the spacecraft, as well as remote characterisation of Jupiter and its satellites. A key instrument on JUICE is the high resolution and wide angle camera, JANUS, whose main science goals include detailed characterisation and study phases of three of the Galilean satellites, Ganymede, Callisto and Europa, as well as studies of other moons, the ring system, and irregular satellites. The CIS115 is a CMOS Active Pixel Sensor from e2v technologies selected for the JANUS camera. It is fabricated using 0.18 μ m CMOS imaging sensor process, with an imaging area of 2000 × 1504 pixels, each 7 μ m square. A 4T pixel architecture allows for efficient correlated double sampling, improving the readout noise to better than 8 electrons rms, whilst the sensor is operated in a rolling shutter mode, sampling at up to 10 Mpixel/s at each of the four parallel outputs.A primary parameter to characterise for an imaging device is the relationship that converts the sensor's voltage output back to the corresponding number of electrons that were detected in a pixel, known as the Charge to Voltage Factor (CVF). In modern CMOS sensors with small feature sizes, the CVF is known to be non-linear with signal level, therefore a signal-dependent measurement of the CIS115's CVF has been undertaken and is presented here. The CVF is well modelled as a quadratic function leading to a measurement of the maximum charge handling capacity of the CIS115 to be 3.4 × 104 electrons. If the CIS115's response is assumed linear, its CVF is 21.1 electrons per mV (1/47.5 μ V per electron).

  3. High responsivity CMOS imager pixel implemented in SOI technology

    NASA Technical Reports Server (NTRS)

    Zheng, X.; Wrigley, C.; Yang, G.; Pain, B.

    2000-01-01

    Availability of mature sub-micron CMOS technology and the advent of the new low noise active pixel sensor (APS) concept have enabled the development of low power, miniature, single-chip, CMOS digital imagers in the decade of the 1990's.

  4. Large area CMOS active pixel sensor x-ray imager for digital breast tomosynthesis: Analysis, modeling, and characterization

    SciTech Connect

    Zhao, Chumin; Kanicki, Jerzy; Konstantinidis, Anastasios C.; Patel, Tushita

    2015-11-15

    Purpose: Large area x-ray imagers based on complementary metal-oxide-semiconductor (CMOS) active pixel sensor (APS) technology have been proposed for various medical imaging applications including digital breast tomosynthesis (DBT). The low electronic noise (50–300 e{sup −}) of CMOS APS x-ray imagers provides a possible route to shrink the pixel pitch to smaller than 75 μm for microcalcification detection and possible reduction of the DBT mean glandular dose (MGD). Methods: In this study, imaging performance of a large area (29 × 23 cm{sup 2}) CMOS APS x-ray imager [Dexela 2923 MAM (PerkinElmer, London)] with a pixel pitch of 75 μm was characterized and modeled. The authors developed a cascaded system model for CMOS APS x-ray imagers using both a broadband x-ray radiation and monochromatic synchrotron radiation. The experimental data including modulation transfer function, noise power spectrum, and detective quantum efficiency (DQE) were theoretically described using the proposed cascaded system model with satisfactory consistency to experimental results. Both high full well and low full well (LFW) modes of the Dexela 2923 MAM CMOS APS x-ray imager were characterized and modeled. The cascaded system analysis results were further used to extract the contrast-to-noise ratio (CNR) for microcalcifications with sizes of 165–400 μm at various MGDs. The impact of electronic noise on CNR was also evaluated. Results: The LFW mode shows better DQE at low air kerma (K{sub a} < 10 μGy) and should be used for DBT. At current DBT applications, air kerma (K{sub a} ∼ 10 μGy, broadband radiation of 28 kVp), DQE of more than 0.7 and ∼0.3 was achieved using the LFW mode at spatial frequency of 0.5 line pairs per millimeter (lp/mm) and Nyquist frequency ∼6.7 lp/mm, respectively. It is shown that microcalcifications of 165–400 μm in size can be resolved using a MGD range of 0.3–1 mGy, respectively. In comparison to a General Electric GEN2 prototype DBT system (at

  5. Analysis of pixel circuits in CMOS image sensors

    NASA Astrophysics Data System (ADS)

    Mei, Zou; Chen, Nan; Yao, Li-bin

    2015-04-01

    CMOS image sensors (CIS) have lower power consumption, lower cost and smaller size than CCD image sensors. However, generally CCDs have higher performance than CIS mainly due to lower noise. The pixel circuit used in CIS is the first part of the signal processing circuit and connected to photodiode directly, so its performance will greatly affect the CIS or even the whole imaging system. To achieve high performance, CMOS image sensors need advanced pixel circuits. There are many pixel circuits used in CIS, such as passive pixel sensor (PPS), 3T and 4T active pixel sensor (APS), capacitive transimpedance amplifier (CTIA), and passive pixel sensor (PPS). At first, the main performance parameters of each pixel structure including the noise, injection efficiency, sensitivity, power consumption, and stability of bias voltage are analyzed. Through the theoretical analysis of those pixel circuits, it is concluded that CTIA pixel circuit has good noise performance, high injection efficiency, stable photodiode bias, and high sensitivity with small integrator capacitor. Furthermore, the APS and CTIA pixel circuits are simulated in a standard 0.18-μm CMOS process and using a n-well/p-sub photodiode by SPICE and the simulation result confirms the theoretical analysis result. It shows the possibility that CMOS image sensors can be extended to a wide range of applications requiring high performance.

  6. Development of CMOS Active Pixel Image Sensors for Low Cost Commercial Applications

    NASA Technical Reports Server (NTRS)

    Gee, R.; Kemeny, S.; Kim, Q.; Mendis, S.; Nakamura, J.; Nixon, R.; Ortiz, M.; Pain, B.; Staller, C.; Zhou, Z; Fossum, E.

    1994-01-01

    JPL, under sponsorship from the NASA Office of Advanced Concepts and Technology, has been developing a second-generation solid-state image sensor technology. Charge-coupled devices (CCD) are a well-established first generation image sensor technology. For both commercial and NASA applications, CCDs have numerous shortcomings. In response, the active pixel sensor (APS) technology has been under research. The major advantages of APS technology are the ability to integrate on-chip timing, control, signal-processing and analog-to-digital converter functions, reduced sensitivity to radiation effects, low power operation, and random access readout.

  7. Optical and electrical characterization of a back-thinned CMOS active pixel sensor

    NASA Astrophysics Data System (ADS)

    Blue, Andrew; Clark, A.; Houston, S.; Laing, A.; Maneuski, D.; Prydderch, M.; Turchetta, R.; O'Shea, V.

    2009-06-01

    This work will report on the first work on the characterization of a back-thinned Vanilla-a 512×512 (25 μm squared) active pixel sensor (APS). Characterization of the detectors was carried out through the analysis of photon transfer curves to yield a measurement of full well capacity, noise levels, gain constants and linearity. Spectral characterization of the sensors was also performed in the visible and UV regions. A full comparison against non-back-thinned front illuminated Vanilla sensors is included. Such measurements suggest that the Vanilla APS will be suitable for a wide range of applications, including particle physics and biomedical imaging.

  8. First tests of CHERWELL, a Monolithic Active Pixel Sensor: A CMOS Image Sensor (CIS) using 180 nm technology

    NASA Astrophysics Data System (ADS)

    Mylroie-Smith, James; Kolya, Scott; Velthuis, Jaap; Bevan, Adrian; Inguglia, Gianluca; Headspith, Jon; Lazarus, Ian; Lemon, Roy; Crooks, Jamie; Turchetta, Renato; Wilson, Fergus

    2013-12-01

    The Cherwell is a 4T CMOS sensor in 180 nm technology developed for the detection of charged particles. Here, the different test structures on the sensor will be described and first results from tests on the reference pixel variant are shown. The sensors were shown to have a noise of 12 e- and a signal to noise up to 150 in 55Fe.

  9. Performance of CMOS imager as sensing element for a Real-time Active Pixel Dosimeter for Interventional Radiology procedures

    NASA Astrophysics Data System (ADS)

    Magalotti, D.; Bissi, L.; Conti, E.; Paolucci, M.; Placidi, P.; Scorzoni, A.; Servoli, L.

    2014-01-01

    Staff members applying Interventional Radiology procedures are exposed to ionizing radiation, which can induce detrimental effects to the human body, and requires an improvement of radiation protection. This paper is focused on the study of the sensor element for a wireless real-time dosimeter to be worn by the medical staff during the interventional radiology procedures, in the framework of the Real-Time Active PIxel Dosimetry (RAPID) INFN project. We characterize a CMOS imager to be used as detection element for the photons scattered by the patient body. The CMOS imager has been first characterized in laboratory using fluorescence X-ray sources, then a PMMA phantom has been used to diffuse the X-ray photons from an angiography system. Different operating conditions have been used to test the detector response in realistic situations, by varying the X-ray tube parameters (continuous/pulsed mode, tube voltage and current, pulse parameters), the sensor parameters (gain, integration time) and the relative distance between sensor and phantom. The sensor response has been compared with measurements performed using passive dosimeters (TLD) and also with a certified beam, in an accredited calibration centre, in order to obtain an absolute calibration. The results are very encouraging, with dose and dose rate measurement uncertainties below the 10% level even for the most demanding Interventional Radiology protocols.

  10. Synchrotron based planar imaging and digital tomosynthesis of breast and biopsy phantoms using a CMOS active pixel sensor.

    PubMed

    Szafraniec, Magdalena B; Konstantinidis, Anastasios C; Tromba, Giuliana; Dreossi, Diego; Vecchio, Sara; Rigon, Luigi; Sodini, Nicola; Naday, Steve; Gunn, Spencer; McArthur, Alan; Olivo, Alessandro

    2015-03-01

    The SYRMEP (SYnchrotron Radiation for MEdical Physics) beamline at Elettra is performing the first mammography study on human patients using free-space propagation phase contrast imaging. The stricter spatial resolution requirements of this method currently force the use of conventional films or specialized computed radiography (CR) systems. This also prevents the implementation of three-dimensional (3D) approaches. This paper explores the use of an X-ray detector based on complementary metal-oxide-semiconductor (CMOS) active pixel sensor (APS) technology as a possible alternative, for acquisitions both in planar and tomosynthesis geometry. Results indicate higher quality of the images acquired with the synchrotron set-up in both geometries. This improvement can be partly ascribed to the use of parallel, collimated and monochromatic synchrotron radiation (resulting in scatter rejection, no penumbra-induced blurring and optimized X-ray energy), and partly to phase contrast effects. Even though the pixel size of the used detector is still too large - and thus suboptimal - for free-space propagation phase contrast imaging, a degree of phase-induced edge enhancement can clearly be observed in the images. PMID:25498332

  11. The Dexela 2923 CMOS X-ray detector: A flat panel detector based on CMOS active pixel sensors for medical imaging applications

    NASA Astrophysics Data System (ADS)

    Konstantinidis, Anastasios C.; Szafraniec, Magdalena B.; Speller, Robert D.; Olivo, Alessandro

    2012-10-01

    Complementary metal-oxide-semiconductors (CMOS) active pixel sensors (APS) have been introduced recently in many scientific applications. This work reports on the performance (in terms of signal and noise transfer) of an X-ray detector that uses a novel CMOS APS which was developed for medical X-ray imaging applications. For a full evaluation of the detector's performance, electro-optical and X-ray characterizations were carried out. The former included measuring read noise, full well capacity and dynamic range. The latter, which included measuring X-ray sensitivity, presampling modulation transfer function (pMTF), noise power spectrum (NPS) and the resulting detective quantum efficiency (DQE), was assessed under three beam qualities (28 kV, 50 kV (RQA3) and 70 kV (RQA5) using W/Al) all in accordance with the IEC standard. The detector features an in-pixel option for switching the full well capacity between two distinct modes, high full well (HFW) and low full well (LFW). Two structured CsI:Tl scintillators of different thickness (a “thin” one for high resolution and a thicker one for high light efficiency) were optically coupled to the sensor array to optimize the performance of the system for different medical applications. The electro-optical performance evaluation of the sensor results in relatively high read noise (∼360 e-), high full well capacity (∼1.5×106 e-) and wide dynamic range (∼73 dB) under HFW mode operation. When the LFW mode is used, the read noise is lower (∼165) at the expense of a reduced full well capacity (∼0.5×106 e-) and dynamic range (∼69 dB). The maximum DQE values at low frequencies (i.e. 0.5 lp/mm) are high for both HFW (0.69 for 28 kV, 0.71 for 50 kV and 0.75 for 70 kV) and LFW (0.69 for 28 kV and 0.7 for 50 kV) modes. The X-ray performance of the studied detector compares well to that of other mammography and general radiography systems, obtained under similar experimental conditions. This demonstrates the suitability

  12. Noise in a CMOS digital pixel sensor

    NASA Astrophysics Data System (ADS)

    Chi, Zhang; Suying, Yao; Jiangtao, Xu

    2011-11-01

    Based on the study of noise performance in CMOS digital pixel sensor (DPS), a mathematical model of noise is established with the pulse-width-modulation (PWM) principle. Compared with traditional CMOS image sensors, the integration time is different and A/D conversion is implemented in each PWM DPS pixel. Then, the quantitative calculating formula of system noise is derived. It is found that dark current shot noise is the dominant noise source in low light region while photodiode shot noise becomes significantly important in the bright region. In this model, photodiode shot noise does not vary with luminance, but dark current shot noise does. According to increasing photodiode capacitance and the comparator's reference voltage or optimizing the mismatch in the comparator, the total noise can be reduced. These results serve as a guideline for the design of PWM DPS.

  13. A CMOS active pixel sensor system for laboratory- based x-ray diffraction studies of biological tissue.

    PubMed

    Bohndiek, Sarah E; Cook, Emily J; Arvanitis, Costas D; Olivo, Alessandro; Royle, Gary J; Clark, Andy T; Prydderch, Mark L; Turchetta, Renato; Speller, Robert D

    2008-02-01

    X-ray diffraction studies give material-specific information about biological tissue. Ideally, a large area, low noise, wide dynamic range digital x-ray detector is required for laboratory-based x-ray diffraction studies. The goal of this work is to introduce a novel imaging technology, the CMOS active pixel sensor (APS) that has the potential to fulfil all these requirements, and demonstrate its feasibility for coherent scatter imaging. A prototype CMOS APS has been included in an x-ray diffraction demonstration system. An industrial x-ray source with appropriate beam filtration is used to perform angle dispersive x-ray diffraction (ADXRD). Optimization of the experimental set-up is detailed including collimator options and detector operating parameters. Scatter signatures are measured for 11 different materials, covering three medical applications: breast cancer diagnosis, kidney stone identification and bone mineral density calculations. Scatter signatures are also recorded for three mixed samples of known composition. Results are verified using two independent models for predicting the APS scatter signature: (1) a linear systems model of the APS and (2) a linear superposition integral combining known monochromatic scatter signatures with the input polychromatic spectrum used in this case. Cross validation of experimental, modelled and literature results proves that APS are able to record biologically relevant scatter signatures. Coherent scatter signatures are sensitive to multiple materials present in a sample and provide a means to quantify composition. In the future, production of a bespoke APS imager for x-ray diffraction studies could enable simultaneous collection of the transmitted beam and scattered radiation in a laboratory-based coherent scatter system, making clinical transfer of the technique attainable. PMID:18199908

  14. Characterization of imaging performance of a large-area CMOS active-pixel detector for low-energy X-ray imaging

    NASA Astrophysics Data System (ADS)

    Hwy Lim, Chang; Yun, Seungman; Chul Han, Jong; Kim, Ho Kyung; Farrier, Michael G.; Graeve Achterkirchen, Thorsten; McDonald, Mike; Cunningham, Ian A.

    2011-10-01

    We report the imaging characteristics of the recently developed large-area complementary metal-oxide-semiconductor (CMOS) active-pixel detector for low-energy digital X-ray imaging applications. The detector consists of a scintillator to convert X-ray into light and a photodiode pixel array made by the CMOS fabrication process to convert light into charge signals. Between two layers, we introduce a fiber-optic faceplate (FOP) to avoid direct absorption of X-ray photons in the photodiode array. A single pixel is composed of a photodiode and three transistors, and the pixel pitch is 96 μm. The imaging characteristics of the detector have been investigated in terms of modulation-transfer function (MTF), noise-power spectrum (NPS), and detective quantum efficiency (DQE). From the measured results, the MTF at the Nyquist frequency is about 20% and the DQE around zero-spatial frequency is about 40%. Simple cascaded linear-systems analysis has showed that the FOP prevents direct absorption of X-ray photons within the CMOS photodiode array, leading to a lower NPS and consequently improved DQE especially at high spatial frequencies.

  15. A novel CMOS sensor with in-pixel auto-zeroed discrimination for charged particle tracking

    NASA Astrophysics Data System (ADS)

    Degerli, Y.; Guilloux, F.; Orsini, F.

    2014-05-01

    With the aim of developing fast and granular Monolithic Active Pixels Sensors (MAPS) as new charged particle tracking detectors for high energy physics experiments, a new rolling shutter binary pixel architecture concept (RSBPix) with in-pixel correlated double sampling, amplification and discrimination is presented. The discriminator features auto-zeroing in order to compensate process-related transistor mismatches. In order to validate the pixel, a first monolithic CMOS sensor prototype, including a pixel array of 96 × 64 pixels, has been designed and fabricated in the Tower-Jazz 0.18 μm CMOS Image Sensor (CIS) process. Results of laboratory tests are presented.

  16. Novel integrated CMOS pixel structures for vertex detectors

    SciTech Connect

    Kleinfelder, Stuart; Bieser, Fred; Chen, Yandong; Gareus, Robin; Matis, Howard S.; Oldenburg, Markus; Retiere, Fabrice; Ritter, Hans Georg; Wieman, Howard H.; Yamamoto, Eugene

    2003-10-29

    Novel CMOS active pixel structures for vertex detector applications have been designed and tested. The overriding goal of this work is to increase the signal to noise ratio of the sensors and readout circuits. A large-area native epitaxial silicon photogate was designed with the aim of increasing the charge collected per struck pixel and to reduce charge diffusion to neighboring pixels. The photogate then transfers the charge to a low capacitance readout node to maintain a high charge to voltage conversion gain. Two techniques for noise reduction are also presented. The first is a per-pixel kT/C noise reduction circuit that produces results similar to traditional correlated double sampling (CDS). It has the advantage of requiring only one read, as compared to two for CDS, and no external storage or subtraction is needed. The technique reduced input-referred temporal noise by a factor of 2.5, to 12.8 e{sup -}. Finally, a column-level active reset technique is explored that suppresses kT/C noise during pixel reset. In tests, noise was reduced by a factor of 7.6 times, to an estimated 5.1 e{sup -} input-referred noise. The technique also dramatically reduces fixed pattern (pedestal) noise, by up to a factor of 21 in our tests. The latter feature may possibly reduce pixel-by-pixel pedestal differences to levels low enough to permit sparse data scan without per-pixel offset corrections.

  17. Empirical electro-optical and x-ray performance evaluation of CMOS active pixels sensor for low dose, high resolution x-ray medical imaging.

    PubMed

    Arvanitis, C D; Bohndiek, S E; Royle, G; Blue, A; Liang, H X; Clark, A; Prydderch, M; Turchetta, R; Speller, R

    2007-12-01

    Monolithic complementary metal oxide semiconductor (CMOS) active pixel sensors with high performance have gained attention in the last few years in many scientific and space applications. In order to evaluate the increasing capabilities of this technology, in particular where low dose high resolution x-ray medical imaging is required, critical electro-optical and physical x-ray performance evaluation was determined. The electro-optical performance includes read noise, full well capacity, interacting quantum efficiency, and pixels cross talk. The x-ray performance, including x-ray sensitivity, modulation transfer function, noise power spectrum, and detection quantum efficiency, has been evaluated in the mammographic energy range. The sensor is a 525 x 525 standard three transistor CMOS active pixel sensor array with more than 75% fill factor and 25 x 25 microm pixel pitch. Reading at 10 f/s, it is found that the sensor has 114 electrons total additive noise, 10(5) electrons full well capacity with shot noise limited operation, and 34% interacting quantum efficiency at 530 nm. Two different structured CsI:Tl phosphors with thickness 95 and 115 microm, respectively, have been optically coupled via a fiber optic plate to the array resulting in two different system configurations. The sensitivity of the two different system configurations was 43 and 47 electrons per x-ray incident on the sensor. The MTF at 10% of the two different system configurations was 9.5 and 9 cycles/mm with detective quantum efficiency of 0.45 and 0.48, respectively, close to zero frequency at approximately 0.44 microC/kg (1.72 mR) detector entrance exposure. The detector was quantum limited at low spatial frequencies and its performance was comparable with high resolution a: Si and charge coupled device based x-ray imagers. The detector also demonstrates almost an order of magnitude lower noise than active matrix flat panel imagers. The results suggest that CMOS active pixel sensors when coupled

  18. Empirical electro-optical and x-ray performance evaluation of CMOS active pixels sensor for low dose, high resolution x-ray medical imaging

    SciTech Connect

    Arvanitis, C. D.; Bohndiek, S. E.; Royle, G.; Blue, A.; Liang, H. X.; Clark, A.; Prydderch, M.; Turchetta, R.; Speller, R.

    2007-12-15

    Monolithic complementary metal oxide semiconductor (CMOS) active pixel sensors with high performance have gained attention in the last few years in many scientific and space applications. In order to evaluate the increasing capabilities of this technology, in particular where low dose high resolution x-ray medical imaging is required, critical electro-optical and physical x-ray performance evaluation was determined. The electro-optical performance includes read noise, full well capacity, interacting quantum efficiency, and pixels cross talk. The x-ray performance, including x-ray sensitivity, modulation transfer function, noise power spectrum, and detection quantum efficiency, has been evaluated in the mammographic energy range. The sensor is a 525x525 standard three transistor CMOS active pixel sensor array with more than 75% fill factor and 25x25 {mu}m pixel pitch. Reading at 10 f/s, it is found that the sensor has 114 electrons total additive noise, 10{sup 5} electrons full well capacity with shot noise limited operation, and 34% interacting quantum efficiency at 530 nm. Two different structured CsI:Tl phosphors with thickness 95 and 115 {mu}m, respectively, have been optically coupled via a fiber optic plate to the array resulting in two different system configurations. The sensitivity of the two different system configurations was 43 and 47 electrons per x-ray incident on the sensor. The MTF at 10% of the two different system configurations was 9.5 and 9 cycles/mm with detective quantum efficiency of 0.45 and 0.48, respectively, close to zero frequency at {approx}0.44 {mu}C/kg (1.72 mR) detector entrance exposure. The detector was quantum limited at low spatial frequencies and its performance was comparable with high resolution a:Si and charge coupled device based x-ray imagers. The detector also demonstrates almost an order of magnitude lower noise than active matrix flat panel imagers. The results suggest that CMOS active pixel sensors when coupled to

  19. Analysis and Enhancement of Low-Light-Level Performance of Photodiode-Type CMOS Active Pixel Images Operated with Sub-Threshold Reset

    NASA Technical Reports Server (NTRS)

    Pain, Bedabrata; Yang, Guang; Ortiz, Monico; Wrigley, Christopher; Hancock, Bruce; Cunningham, Thomas

    2000-01-01

    Noise in photodiode-type CMOS active pixel sensors (APS) is primarily due to the reset (kTC) noise at the sense node, since it is difficult to implement in-pixel correlated double sampling for a 2-D array. Signal integrated on the photodiode sense node (SENSE) is calculated by measuring difference between the voltage on the column bus (COL) - before and after the reset (RST) is pulsed. Lower than kTC noise can be achieved with photodiode-type pixels by employing "softreset" technique. Soft-reset refers to resetting with both drain and gate of the n-channel reset transistor kept at the same potential, causing the sense node to be reset using sub-threshold MOSFET current. However, lowering of noise is achieved only at the expense higher image lag and low-light-level non-linearity. In this paper, we present an analysis to explain the noise behavior, show evidence of degraded performance under low-light levels, and describe new pixels that eliminate non-linearity and lag without compromising noise.

  20. From hybrid to CMOS pixels ... a possibility for LHC's pixel future?

    NASA Astrophysics Data System (ADS)

    Wermes, N.

    2015-12-01

    Hybrid pixel detectors have been invented for the LHC to make tracking and vertexing possible at all in LHC's radiation intense environment. The LHC pixel detectors have meanwhile very successfully fulfilled their promises and R&D for the planned HL-LHC upgrade is in full swing, targeting even higher ionising doses and non-ionising fluences. In terms of rate and radiation tolerance hybrid pixels are unrivaled. But they have disadvantages as well, most notably material thickness, production complexity, and cost. Meanwhile also active pixel sensors (DEPFET, MAPS) have become real pixel detectors but they would by far not stand the rates and radiation faced from HL-LHC. New MAPS developments, so-called DMAPS (depleted MAPS) which are full CMOS-pixel structures with charge collection in a depleted region have come in the R&D focus for pixels at high rate/radiation levels. This goal can perhaps be realised exploiting HV technologies, high ohmic substrates and/or SOI based technologies. The paper covers the main ideas and some encouraging results from prototyping R&D, not hiding the difficulties.

  1. Depleted CMOS pixels for LHC proton-proton experiments

    NASA Astrophysics Data System (ADS)

    Wermes, N.

    2016-07-01

    While so far monolithic pixel detectors have remained in the realm of comparatively low rate and radiation applications outside LHC, new developments exploiting high resistivity substrates with three or four well CMOS process options allow reasonably large depletion depths and full CMOS circuitry in a monolithic structure. This opens up the possibility to target CMOS pixel detectors also for high radiation pp-experiments at the LHC upgrade, either in a hybrid-type fashion or even fully monolithic. Several pixel matrices have been prototyped with high ohmic substrates, high voltage options, and full CMOS electronics. They were characterized in the lab and in test beams. An overview of the necessary development steps and different approaches as well as prototype results are presented in this paper.

  2. Fully depleted, thick, monolithic CMOS pixels with high quantum efficiency

    NASA Astrophysics Data System (ADS)

    Clarke, A.; Stefanov, K.; Johnston, N.; Holland, A.

    2015-04-01

    The Centre for Electronic Imaging (CEI) has an active programme of evaluating and designing Complementary Metal-Oxide Semiconductor (CMOS) image sensors with high quantum efficiency, for applications in near-infrared and X-ray photon detection. This paper describes the performance characterisation of CMOS devices made on a high resistivity 50 μ m thick p-type substrate with a particular focus on determining the depletion depth and the quantum efficiency. The test devices contain 8 × 8 pixel arrays using CCD-style charge collection, which are manufactured in a low voltage CMOS process by ESPROS Photonics Corporation (EPC). Measurements include determining under which operating conditions the devices become fully depleted. By projecting a spot using a microscope optic and a LED and biasing the devices over a range of voltages, the depletion depth will change, causing the amount of charge collected in the projected spot to change. We determine if the device is fully depleted by measuring the signal collected from the projected spot. The analysis of spot size and shape is still under development.

  3. Performance of capacitively coupled active pixel sensors in 180 nm HV-CMOS technology after irradiation to HL-LHC fluences

    NASA Astrophysics Data System (ADS)

    Feigl, S.

    2014-03-01

    In this ATLAS upgrade R&D project, we explore the concept of using a deep-submicron HV-CMOS process to produce a drop-in replacement for traditional radiation-hard silicon sensors. Such active sensors contain simple circuits, e.g. amplifiers and discriminators, but still require a traditional (pixel or strip) readout chip. This approach yields most advantages of MAPS (improved resolution, reduced cost and material budget, etc.), without the complication of full integration on a single chip. After outlining the basic design of the HV2FEI4 test ASIC, results after irradiation with X-rays to 862 Mrad and neutrons up to 1016(1 MeV neq)/cm2 will be presented. Finally, a brief outlook on further development plans is given.

  4. Development of a CMOS SOI Pixel Detector

    SciTech Connect

    Arai, Y.; Hazumi, M.; Ikegami, Y.; Kohriki, T.; Tajima, O.; Terada, S.; Tsuboyama, T.; Unno, Y.; Ushiroda, Y.; Ikeda, H.; Hara, K.; Ishino, H.; Kawasaki, T.; Miyake, H.; Martin, E.; Varner, G.; Tajima, H.; Ohno, M.; Fukuda, K.; Komatsubara, H.; Ida, J.; /NONE - OKI ELECTR INDUST TOKYO

    2008-08-19

    We have developed a monolithic radiation pixel detector using silicon on insulator (SOI) with a commercial 0.15 {micro}m fully-depleted-SOI technology and a Czochralski high resistivity silicon substrate in place of a handle wafer. The SOI TEG (Test Element Group) chips with a size of 2.5 x 2.5 mm{sup 2} consisting of 20 x 20 {micro}m{sup 2} pixels have been designed and manufactured. Performance tests with a laser light illumination and a {beta} ray radioactive source indicate successful operation of the detector. We also briefly discuss the back gate effect as well as the simulation study.

  5. Amorphous selenium direct detection CMOS digital x-ray imager with 25 micron pixel pitch

    NASA Astrophysics Data System (ADS)

    Scott, Christopher C.; Abbaszadeh, Shiva; Ghanbarzadeh, Sina; Allan, Gary; Farrier, Michael; Cunningham, Ian A.; Karim, Karim S.

    2014-03-01

    We have developed a high resolution amorphous selenium (a-Se) direct detection imager using a large-area compatible back-end fabrication process on top of a CMOS active pixel sensor having 25 micron pixel pitch. Integration of a-Se with CMOS technology requires overcoming CMOS/a-Se interfacial strain, which initiates nucleation of crystalline selenium and results in high detector dark currents. A CMOS-compatible polyimide buffer layer was used to planarize the backplane and provide a low stress and thermally stable surface for a-Se. The buffer layer inhibits crystallization and provides detector stability that is not only a performance factor but also critical for favorable long term cost-benefit considerations in the application of CMOS digital x-ray imagers in medical practice. The detector structure is comprised of a polyimide (PI) buffer layer, the a-Se layer, and a gold (Au) top electrode. The PI layer is applied by spin-coating and is patterned using dry etching to open the backplane bond pads for wire bonding. Thermal evaporation is used to deposit the a-Se and Au layers, and the detector is operated in hole collection mode (i.e. a positive bias on the Au top electrode). High resolution a-Se diagnostic systems typically use 70 to 100 μm pixel pitch and have a pre-sampling modulation transfer function (MTF) that is significantly limited by the pixel aperture. Our results confirm that, for a densely integrated 25 μm pixel pitch CMOS array, the MTF approaches the fundamental material limit, i.e. where the MTF begins to be limited by the a-Se material properties and not the pixel aperture. Preliminary images demonstrating high spatial resolution have been obtained from a frst prototype imager.

  6. A CMOS In-Pixel CTIA High Sensitivity Fluorescence Imager

    PubMed Central

    Murari, Kartikeya; Etienne-Cummings, Ralph; Thakor, Nitish; Cauwenberghs, Gert

    2012-01-01

    Traditionally, charge coupled device (CCD) based image sensors have held sway over the field of biomedical imaging. Complementary metal oxide semiconductor (CMOS) based imagers so far lack sensitivity leading to poor low-light imaging. Certain applications including our work on animal-mountable systems for imaging in awake and unrestrained rodents require the high sensitivity and image quality of CCDs and the low power consumption, flexibility and compactness of CMOS imagers. We present a 132×124 high sensitivity imager array with a 20.1 μm pixel pitch fabricated in a standard 0.5 μ CMOS process. The chip incorporates n-well/p-sub photodiodes, capacitive transimpedance amplifier (CTIA) based in-pixel amplification, pixel scanners and delta differencing circuits. The 5-transistor all-nMOS pixel interfaces with peripheral pMOS transistors for column-parallel CTIA. At 70 fps, the array has a minimum detectable signal of 4 nW/cm2 at a wavelength of 450 nm while consuming 718 μA from a 3.3 V supply. Peak signal to noise ratio (SNR) was 44 dB at an incident intensity of 1 μW/cm2. Implementing 4×4 binning allowed the frame rate to be increased to 675 fps. Alternately, sensitivity could be increased to detect about 0.8 nW/cm2 while maintaining 70 fps. The chip was used to image single cell fluorescence at 28 fps with an average SNR of 32 dB. For comparison, a cooled CCD camera imaged the same cell at 20 fps with an average SNR of 33.2 dB under the same illumination while consuming over a watt. PMID:23136624

  7. Development of CMOS Pixel Sensors with digital pixel dedicated to future particle physics experiments

    NASA Astrophysics Data System (ADS)

    Zhao, W.; Wang, T.; Pham, H.; Hu-Guo, C.; Dorokhov, A.; Hu, Y.

    2014-02-01

    Two prototypes of CMOS pixel sensor with in-pixel analog to digital conversion have been developed in a 0.18 μm CIS process. The first design integrates a discriminator into each pixel within an area of 22 × 33 μm2 in order to meet the requirements of the ALICE inner tracking system (ALICE-ITS) upgrade. The second design features 3-bit charge encoding inside a 35 × 35 μm2 pixel which is motivated by the specifications of the outer layers of the ILD vertex detector (ILD-VXD). This work aims to validate the concept of in-pixel digitization which offers higher readout speed, lower power consumption and less dead zone compared with the column-level charge encoding.

  8. Design of an ultra low power CMOS pixel sensor for a future neutron personal dosimeter

    SciTech Connect

    Zhang, Y.; Hu-Guo, C.; Husson, D.; Hu, Y.

    2011-07-01

    Despite a continuously increasing demand, neutron electronic personal dosimeters (EPDs) are still far from being completely established because their development is a very difficult task. A low-noise, ultra low power consumption CMOS pixel sensor for a future neutron personal dosimeter has been implemented in a 0.35 {mu}m CMOS technology. The prototype is composed of a pixel array for detection of charged particles, and the readout electronics is integrated on the same substrate for signal processing. The excess electrons generated by an impinging particle are collected by the pixel array. The charge collection time and the efficiency are the crucial points of a CMOS detector. The 3-D device simulations using the commercially available Synopsys-SENTAURUS package address the detailed charge collection process. Within a time of 1.9 {mu}s, about 59% electrons created by the impact particle are collected in a cluster of 4 x 4 pixels with the pixel pitch of 80 {mu}m. A charge sensitive preamplifier (CSA) and a shaper are employed in the frond-end readout. The tests with electrical signals indicate that our prototype with a total active area of 2.56 x 2.56 mm{sup 2} performs an equivalent noise charge (ENC) of less than 400 e - and 314 {mu}W power consumption, leading to a promising prototype. (authors)

  9. Active pixel sensors with substantially planarized color filtering elements

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R. (Inventor); Kemeny, Sabrina E. (Inventor)

    1999-01-01

    A semiconductor imaging system preferably having an active pixel sensor array compatible with a CMOS fabrication process. Color-filtering elements such as polymer filters and wavelength-converting phosphors can be integrated with the image sensor.

  10. Low-noise CMOS SPAD arrays with in-pixel time-to-digital converters

    NASA Astrophysics Data System (ADS)

    Tosi, Alberto; Villa, Federica; Bronzi, Danilo; Zou, Yu; Lussana, Rudi; Tamborini, Davide; Tisa, Simone; Durini, Daniel; Weyers, Sascha; Pashen, Uwe; Brockherde, Werner; Zappa, Franco

    2014-05-01

    We present our latest results concerning CMOS Single-Photon Avalanche Diode (SPAD) arrays for high-throughput parallel single-photon counting. We exploited a high-voltage 0.35 μm CMOS technology in order to develop low-noise CMOS SPADs. The Dark Count Rate is 30 cps at room temperature for 30 μm devices, increases to 2 kcps for 100 μm SPADs and just to 100 kcps for 500 μm ones. Afterpulsing is less than 1% for hold-off time longer than 50 ns, thus allowing to reach high count rates. Photon Detection Efficiency is > 50% at 420 nm, > 40% below 500 nm and is still 5% at 850 nm. Timing jitter is less than 100 ps (FWHM) in SPADs with active area diameter up to 50 μm. We developed CMOS SPAD imagers with 150 μm pixel pitch and 30 μm SPADs. A 64×32 SPAD array is based on pixels including three 9-bit counters for smart phase-resolved photon counting up to 100 kfps. A 32x32 SPAD array includes 1024 10-bit Time-to-Digital Converters (TDC) with 300 ps resolution and 450 ps single-shot precision, for 3D ranging and FLIM. We developed also linear arrays with up to 60 pixels (with 100 μm SPAD, 150 μm pitch and in-pixel 250 ps TDC) for time-resolved parallel spectroscopy with high fill factor.

  11. Characterization of a Depleted Monolithic Active Pixel Sensor (DMAPS) prototype

    NASA Astrophysics Data System (ADS)

    Obermann, T.; Havranek, M.; Hemperek, T.; Hügging, F.; Kishishita, T.; Krüger, H.; Marinas, C.; Wermes, N.

    2015-03-01

    New monolithic pixel detectors integrating CMOS electronics and sensor on the same silicon substrate are currently explored for particle tracking in future HEP experiments, most notably at the LHC . The innovative concept of Depleted Monolithic Active Pixel Sensors (DMAPS) is based on high resistive silicon bulk material enabling full substrate depletion and the application of an electrical drift field for fast charge collection, while retaining full CMOS capability for the electronics. The technology (150 nm) used offers quadruple wells and allows to implement the pixel electronics with independently isolated N- and PMOS transistors. Results of initial studies on the charge collection and sensor performance are presented.

  12. Characterization of a three side abuttable CMOS pixel sensor with digital pixel and data compression for charged particle tracking

    NASA Astrophysics Data System (ADS)

    Guilloux, F.; Değerli, Y.; Flouzat, C.; Lachkar, M.; Monmarthe, E.; Orsini, F.; Venault, P.

    2016-02-01

    CMOS monolithic pixel sensor technology has been chosen to equip the new ALICE trackers for HL-LHC . PIXAM is the final prototype from an R&D program specific to the Muon Forward Tracker which intends to push significantly forward the performances of the mature rolling shutter architecture. By implementing a digital pixel allowing to readout of a group of rows in parallel, the PIXAM sensor increases the rolling shutter readout speed while keeping the same power consumption as that of analogue pixel sensors. This paper will describe shortly the ASIC architecture and will focus on the analogue and digital performances of the sensor, obtained from laboratory measurements.

  13. Using an Active Pixel Sensor In A Vertex Detector

    SciTech Connect

    Matis, Howard S.; Bieser, Fred; Chen, Yandong; Gareus, Robin; Kleinfelder, Stuart; Oldenburg, Markus; Retiere, Fabrice; Ritter, HansGeorg; Wieman, Howard H.; Wurzel, Samuel E.; Yamamoto, Eugene

    2004-04-22

    Research has shown that Active Pixel CMOS sensors can detect charged particles. We have been studying whether this process can be used in a collider environment. In particular, we studied the effect of radiation with 55 MeV protons. These results show that a fluence of about 2 x 10{sup 12} protons/cm{sup 2} reduces the signal by a factor of two while the noise increases by 25%. A measurement 6 months after exposure shows that the silicon lattice naturally repairs itself. Heating the silicon to 100 C reduced the shot noise and increased the collected charge. CMOS sensors have a reduced signal to noise ratio per pixel because charge diffuses to neighboring pixels. We have constructed a photogate to see if this structure can collect more charge per pixel. Results show that a photogate does collect charge in fewer pixels, but it takes about 15 ms to collect all of the electrons produced by a pulse of light.

  14. Power and area efficient 4-bit column-level ADC in a CMOS pixel sensor for the ILD vertex detector

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Morel, F.; Hu-Guo, Ch; Hu, Y.

    2013-01-01

    A 48 × 64 pixels prototype CMOS pixel sensor (CPS) integrated with 4-bit column-level, self triggered ADCs for the outer layers of the ILD vertex detector (VTX) was developed and fabricated in a 0.35 μm CMOS process with a pixel pitch of 35 μm. The pixel concept combines in-pixel amplification with a correlated double sampling (CDS) operation. The ADCs accommodating the pixel read out in a rolling shutter mode complete the conversion by performing a multi-bit/step approximation. The design was optimised for power saving at sampling frequency. The prototype sensor is currently at the stage of being started testing and evaluation. So what is described is based on post simulation results rather than test data. This 4-bit ADC dissipates, at a 3-V supply and 6.25-MS/s sampling rate, 486 μW in its inactive mode, which is by far the most frequent. This value rises to 714 μW in case of the active mode. Its footprint amounts to 35 × 545 μm2.

  15. A high frame rate, 16 million pixels, radiation hard CMOS sensor

    NASA Astrophysics Data System (ADS)

    Guerrini, N.; Turchetta, R.; Van Hoften, G.; Henderson, R.; McMullan, G.; Faruqi, A. R.

    2011-03-01

    CMOS sensors provide the possibility of designing detectors for a large variety of applications with all the benefits and flexibility of the widely used CMOS process. In this paper we describe a novel CMOS sensor designed for transmission electron microscopy. The overall design consists of a large 61 × 63 mm2 silicon area containing 16 million pixels arranged in a 4K × 4K array, with radiation hard geometry. All this is combined with a very fast readout, the possibility of region of interest (ROI) readout, pixel binning with consequent frame rate increase and a dynamic range close to 12 bits. The high frame rate has been achieved using 32 parallel analogue outputs each one operating at up to 20 MHz. Binning of pixels can be controlled externally and the flexibility of the design allows several possibilities, such as 2 × 2 or 4 × 4 binning. Other binning configurations where the number of rows and the number of columns are not equal, such as 2 × 1 or 2 × 4, are also possible. Having control of the CMOS design allowed us to optimise the pixel design, in particular with regard to its radiation hardness, and to make optimum choices in the design of other regions of the final sensor. An early prototype was also designed with a variety of geometries in order to optimise the readout structure and these are presented. The sensor was manufactured in a 0.35 μm standard CMOS process.

  16. 1T Pixel Using Floating-Body MOSFET for CMOS Image Sensors

    PubMed Central

    Lu, Guo-Neng; Tournier, Arnaud; Roy, François; Deschamps, Benoît

    2009-01-01

    We present a single-transistor pixel for CMOS image sensors (CIS). It is a floating-body MOSFET structure, which is used as photo-sensing device and source-follower transistor, and can be controlled to store and evacuate charges. Our investigation into this 1T pixel structure includes modeling to obtain analytical description of conversion gain. Model validation has been done by comparing theoretical predictions and experimental results. On the other hand, the 1T pixel structure has been implemented in different configurations, including rectangular-gate and ring-gate designs, and variations of oxidation parameters for the fabrication process. The pixel characteristics are presented and discussed. PMID:22389592

  17. 1T Pixel Using Floating-Body MOSFET for CMOS Image Sensors.

    PubMed

    Lu, Guo-Neng; Tournier, Arnaud; Roy, François; Deschamps, Benoît

    2009-01-01

    We present a single-transistor pixel for CMOS image sensors (CIS). It is a floating-body MOSFET structure, which is used as photo-sensing device and source-follower transistor, and can be controlled to store and evacuate charges. Our investigation into this 1T pixel structure includes modeling to obtain analytical description of conversion gain. Model validation has been done by comparing theoretical predictions and experimental results. On the other hand, the 1T pixel structure has been implemented in different configurations, including rectangular-gate and ring-gate designs, and variations of oxidation parameters for the fabrication process. The pixel characteristics are presented and discussed. PMID:22389592

  18. Large area CMOS bio-pixel array for compact high sensitive multiplex biosensing.

    PubMed

    Sandeau, Laure; Vuillaume, Cassandre; Contié, Sylvain; Grinenval, Eva; Belloni, Federico; Rigneault, Hervé; Owens, Roisin M; Fournet, Margaret Brennan

    2015-02-01

    A novel CMOS bio-pixel array which integrates assay substrate and assay readout is demonstrated for multiplex and multireplicate detection of a triplicate of cytokines with single digit pg ml(-1) sensitivities. Uniquely designed large area bio-pixels enable individual assays to be dedicated to and addressed by single pixels. A capability to simultaneously measure a large number of targets is provided by the 128 available pixels. Chemiluminescent assays are carried out directly on the pixel surface which also detects the emitted chemiluminescent photons, facilitating a highly compact sensor and reader format. The high sensitivity of the bio-pixel array is enabled by the high refractive index of silicon based pixels. This in turn generates a strong supercritical angle luminescence response significantly increasing the efficiency of the photon collection over conventional farfield modalities. PMID:25490928

  19. Compact all-CMOS spatiotemporal compressive sensing video camera with pixel-wise coded exposure.

    PubMed

    Zhang, Jie; Xiong, Tao; Tran, Trac; Chin, Sang; Etienne-Cummings, Ralph

    2016-04-18

    We present a low power all-CMOS implementation of temporal compressive sensing with pixel-wise coded exposure. This image sensor can increase video pixel resolution and frame rate simultaneously while reducing data readout speed. Compared to previous architectures, this system modulates pixel exposure at the individual photo-diode electronically without external optical components. Thus, the system provides reduction in size and power compare to previous optics based implementations. The prototype image sensor (127 × 90 pixels) can reconstruct 100 fps videos from coded images sampled at 5 fps. With 20× reduction in readout speed, our CMOS image sensor only consumes 14μW to provide 100 fps videos. PMID:27137331

  20. A High-Speed CMOS Image Sensor with Global Electronic Shutter Pixels Using Pinned Diodes

    NASA Astrophysics Data System (ADS)

    Yasutomi, Keita; Tamura, Toshihiro; Furuta, Masanori; Itoh, Shinya; Kawahito, Shoji

    This paper describes a high-speed CMOS image sensor with a new type of global electronic shutter pixel. A global electronic shutter is necessary for imaging fast-moving objects without motion blur or distortion. The proposed pixel has two potential wells with pinned diode structure for two-stage charge transfer that enables a global electronic shuttering and reset noise canceling. A prototype high-speed image sensor fabricated in 0.18μm standard CMOS image sensor process consists of the proposed pixel array, 12-bit column-parallel cyclic ADC arrays and 192-channel digital outputs. The sensor achieves a good linearity at low-light intensity, demonstrating the perfect charge transfer between two pinned diodes. The input referred noise of the proposed pixel is measured to be 6.3 e-.

  1. A low-power and small-area column-level ADC for high frame-rate CMOS pixel sensor

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Morel, F.; Hu-Guo, C.; Hu, Y.

    2014-07-01

    CMOS pixel sensors (CPS) have demonstrated performances meeting the specifications of the International Linear Collider (ILC) vertex detector (VTX). This paper presents a low-power and small-area 4-bit column-level analog-to-digital converter (ADC) for CMOS pixel sensors. The ADC employs a self-timed trigger and completes the conversion by performing a multi-bit/step approximation. As in the outer layers of the ILC vertex detector hit density is of the order of a few per thousand, in order to reduce power consumption, the ADC is designed to work in two modes: active mode and idle mode. The ADC is fabricated in a 0.35 μm CMOS process with a pixel pitch of 35 μm. It is implemented with 48 columns in a sensor prototype. Each column ADC covers an area of 35 ×545 μm2. The measured temporal noise and Fixed Pattern Noise (FPN) are 0.96 mV and 0.40 mV, respectively. The power consumption, for a 3 V supply and 6.25 MS/s sampling rate, is 486 μW during idle time, which is by far the most frequently employed one. This value rises to 714 μW in the case of the active mode. The measured differential nonlinearity (DNL) and integral nonlinearity (INL) are 0.49/-0.28 LSB and 0.29/-0.20 LSB, respectively.

  2. CMOS readout integrated circuit involving pixel-level ADC for microbolometer FPAs

    NASA Astrophysics Data System (ADS)

    Hwang, C. H.; Kwon, I. W.; Lee, Y. S.; Lee, H. C.

    2008-04-01

    The function of most readout integrated circuits (ROIC) for microbolometer focal plane arrays (FPAs) is supplying a bias voltage to a microbolometer of each pixel, integrating the current of a microbolometer, and transferring the signals from pixels to the output of a chip. However, the scale down of CMOS technology allows the integration of other functions. In this paper, we proposed a CMOS ROIC involving a pixel-level analog-to-digital converter (ADC) for 320 × 240 microbolometer FPAs. Such integration would improve the performance of a ROIC at the reduced system cost and power consumption. The noise performance of a microbolometer is improved by using the pixelwise readout structure because integration time can be increased up to 1ms. A Pixel circuit is consisted of a background skimming circuit, a differential amplifier, an integration capacitor and a 10-bit DRAM. First, the microbolometer current is integrated for 1ms after the skimming current correction. The differential amplifier operates as an op-Amp and the integration capacitor makes negative feedback loop between an output and a negative input of the op-Amp. And then, the integrated signal voltage is converted to digital signals using a modified single slope ADC in a pixel when the differential amplifier operates as a comparator and the 10-bit DRAM stores values of a counter. This readout circuit is designed and fabricated using a standard 0.35μm 2-poly 3-metal CMOS technology.

  3. High Speed, Radiation Hard CMOS Pixel Sensors for Transmission Electron Microscopy

    NASA Astrophysics Data System (ADS)

    Contarato, Devis; Denes, Peter; Doering, Dionisio; Joseph, John; Krieger, Brad

    CMOS monolithic active pixel sensors are currently being established as the technology of choice for new generation digital imaging systems in Transmission Electron Microscopy (TEM). A careful sensor design that couples μm-level pixel pitches with high frame rate readout and radiation hardness to very high electron doses enables the fabrication of direct electron detectors that are quickly revolutionizing high-resolution TEM imaging in material science and molecular biology. This paper will review the principal characteristics of this novel technology and its advantages over conventional, optically-coupled cameras, and retrace the sensor development driven by the Transmission Electron Aberration corrected Microscope (TEAM) project at the LBNL National Center for Electron Microscopy (NCEM), illustrating in particular the imaging capabilities enabled by single electron detection at high frame rate. Further, the presentation will report on the translation of the TEAM technology to a finer feature size process, resulting in a sensor with higher spatial resolution and superior radiation tolerance currently serving as the baseline for a commercial camera system.

  4. High dynamic range CMOS image sensor with pixel level ADC and in-situ image enhancement

    NASA Astrophysics Data System (ADS)

    Harton, Austin V.; Ahmed, Mohamed I.; Beuhler, Allyson; Castro, Francisco; Dawson, Linda M.; Herold, Barry W.; Kujawa, Gregory; Lee, King F.; Mareachen, Russell D.; Scaminaci, Tony J.

    2005-03-01

    We describe a CMOS image sensor with pixel level analog to digital conversion (ADC) having high dynamic range (>100db) and the capability of performing many image processing functions at the pixel level during image capture. The sensor has a 102x98 pixel array and is implemented in a 0.18um CMOS process technology. Each pixel is 15.5um x15.5um with 15% fill factor and is comprised of a comparator, two 10 bit memory registers and control logic. A digital to analog converter and system processor are located off-chip. The photodetector produces a photocurrent yielding a photo-voltage proportional to the impinging light intensity. Once the photo-voltage is less than a predetermined global reference voltage; a global code value is latched into the pixel data buffer. This process prevents voltage saturation resulting in high dynamic range imaging. Upon completion of image capture, a digital representation of the image exists at the pixel array, thereby, allowing image data to be accessed in a parallel fashion from the focal plane array. It is demonstrated that by appropriate variation of the global reference voltage with time, it is possible to perform, during image capture, thresholding and image enhancement operations, such as, contrast stretching in a parallel manner.

  5. A high fill-factor low dark leakage CMOS image sensor with shared-pixel design

    NASA Astrophysics Data System (ADS)

    Seo, Min-Woong; Yasutomi, Keita; Kagawa, Keiichiro; Kawahito, Shoji

    2014-03-01

    We have developed and evaluated the high responsivity and low dark leakage CMOS image sensor with the ring-gate shared-pixel design. A ring-gate shared-pixel design with a high fill factor makes it possible to achieve the low-light imaging. As eliminating the shallow trench isolation in the proposed pixel, the dark leakage current is significantly decreased because one of major dark leakage sources is removed. By sharing the in-pixel transistors such as a reset transistor, a select transistor, and a source follower amplifier, each pixel has a high fill-factor of 43 % and high sensitivity of 144.6 ke-/lx·sec. In addition, the effective number of transistors per pixel is 1.75. The proposed imager achieved the relatively low dark leakage current of about 104.5 e-/s (median at 60°C), corresponding to a dark current density Jdark_proposed of about 30 pA/cm2. In contrast, the conventional type test pixel has a large dark leakage current of 2450 e-/s (median at 60°C), corresponding to Jdark_conventional of about 700 pA/cm2. Both pixels have a same pixel size of 7.5×7.5 μm2 and are fabricated in same process.

  6. A CMOS image sensor using high-speed lock-in pixels for stimulated Raman scattering

    NASA Astrophysics Data System (ADS)

    Lioe, DeXing; Mars, Kamel; Takasawa, Taishi; Yasutomi, Keita; Kagawa, Keiichiro; Hashimoto, Mamoru; Kawahito, Shoji

    2016-03-01

    A CMOS image sensor using high-speed lock-in pixels for stimulated Raman scattering (SRS) spectroscopy is presented in this paper. The effective SRS signal from the stimulated emission of SRS mechanism is very small in contrast to the offset of a probing laser source, which is in the ratio of 10-4 to 10-5. In order to extract this signal, the common offset component is removed, and the small difference component is sampled using switched-capacitor integrator with a fully differential amplifier. The sampling is performed over many integration cycles to achieve appropriate amplification. The lock-in pixels utilizes high-speed lateral electric field charge modulator (LEFM) to demodulate the SRS signal which is modulated at high-frequency of 20MHz. A prototype chip is implemented using 0.11μm CMOS image sensor technology.

  7. A low-noise CMOS pixel direct charge sensor, Topmetal-II-

    NASA Astrophysics Data System (ADS)

    An, Mangmang; Chen, Chufeng; Gao, Chaosong; Han, Mikyung; Ji, Rong; Li, Xiaoting; Mei, Yuan; Sun, Quan; Sun, Xiangming; Wang, Kai; Xiao, Le; Yang, Ping; Zhou, Wei

    2016-02-01

    We report the design and characterization of a CMOS pixel direct charge sensor, Topmetal-II-, fabricated in a standard 0.35 μm CMOS Integrated Circuit process. The sensor utilizes exposed metal patches on top of each pixel to directly collect charge. Each pixel contains a low-noise charge-sensitive preamplifier to establish the analog signal and a discriminator with tunable threshold to generate hits. The analog signal from each pixel is accessible through time-shared multiplexing over the entire array. Hits are read out digitally through a column-based priority logic structure. Tests show that the sensor achieved a < 15e- analog noise and a 200e- minimum threshold for digital readout per pixel. The sensor is capable of detecting both electrons and ions drifting in gas. These characteristics enable its use as the charge readout device in future Time Projection Chambers without gaseous gain mechanism, which has unique advantages in low background and low rate-density experiments.

  8. Denoising Algorithm for the Pixel-Response Non-Uniformity Correction of a Scientific CMOS Under Low Light Conditions

    NASA Astrophysics Data System (ADS)

    Hu, Changmiao; Bai, Yang; Tang, Ping

    2016-06-01

    We present a denoising algorithm for the pixel-response non-uniformity correction of a scientific complementary metal-oxide-semiconductor (CMOS) image sensor, which captures images under extremely low-light conditions. By analyzing the integrating sphere experimental data, we present a pixel-by-pixel flat-field denoising algorithm to remove this fixed pattern noise, which occur in low-light conditions and high pixel response readouts. The response of the CMOS image sensor imaging system to the uniform radiance field shows a high level of spatial uniformity after the denoising algorithm has been applied.

  9. Ultra-thin silicon (UTSi) on insulator CMOS transceiver and time-division multiplexed switch chips for smart pixel integration

    NASA Astrophysics Data System (ADS)

    Zhang, Liping; Sawchuk, Alexander A.

    2001-12-01

    We describe the design, fabrication and functionality of two different 0.5 micron CMOS optoelectronic integrated circuit (OEIC) chips based on the Peregrine Semiconductor Ultra-Thin Silicon on insulator technology. The Peregrine UTSi silicon- on-sapphire (SOS) technology is a member of the silicon-on- insulator (SOI) family. The low-loss synthetic sapphire substrate is optically transparent and has good thermal conductivity and coefficient of thermal expansion properties, which meet the requirements for flip-chip bonding of VCSELs and other optoelectronic input-output components. One chip contains transceiver and network components, including four channel high-speed CMOS transceiver modules, pseudo-random bit stream (PRBS) generators, a voltage controlled oscillator (VCO) and other test circuits. The transceiver chips can operate in both self-testing mode and networking mode. An on- chip clock and true-single-phase-clock (TSPC) D-flip-flop have been designed to generate a PRBS at over 2.5 Gb/s for the high-speed transceiver arrays to operate in self-testing mode. In the networking mode, an even number of transceiver chips forms a ring network through free-space or fiber ribbon interconnections. The second chip contains four channel optical time-division multiplex (TDM) switches, optical transceiver arrays, an active pixel detector and additional test devices. The eventual applications of these chips will require monolithic OEICs with integrated optical input and output. After fabrication and testing, the CMOS transceiver array dies will be packaged with 850 nm vertical cavity surface emitting lasers (VCSELs), and metal-semiconductor- metal (MSM) or GaAs p-i-n detector die arrays to achieve high- speed optical interconnections. The hybrid technique could be either wire bonding or flip-chip bonding of the CMOS SOS smart-pixel arrays with arrays of VCSELs and photodetectors onto an optoelectronic chip carrier as a multi-chip module (MCM).

  10. A CMOS pixel sensor prototype for the outer layers of linear collider vertex detector

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Morel, F.; Hu-Guo, C.; Himmi, A.; Dorokhov, A.; Hu, Y.

    2015-01-01

    The International Linear Collider (ILC) expresses a stringent requirement for high precision vertex detectors (VXD). CMOS pixel sensors (CPS) have been considered as an option for the VXD of the International Large Detector (ILD), one of the detector concepts proposed for the ILC. MIMOSA-31 developed at IPHC-Strasbourg is the first CPS integrated with 4-bit column-level ADC for the outer layers of the VXD, adapted to an original concept minimizing the power consumption. It is composed of a matrix of 64 rows and 48 columns. The pixel concept combines in-pixel amplification with a correlated double sampling (CDS) operation in order to reduce the temporal noise and fixed pattern noise (FPN). At the bottom of the pixel array, each column is terminated with a self-triggered analog-to-digital converter (ADC). The ADC design was optimized for power saving at a sampling frequency of 6.25 MS/s. The prototype chip is fabricated in a 0.35 μm CMOS technology. This paper presents the details of the prototype chip and its test results.

  11. Mask-less ultraviolet photolithography based on CMOS-driven micro-pixel light emitting diodes.

    PubMed

    Elfström, D; Guilhabert, B; McKendry, J; Poland, S; Gong, Z; Massoubre, D; Richardson, E; Rae, B R; Valentine, G; Blanco-Gomez, G; Gu, E; Cooper, J M; Henderson, R K; Dawson, M D

    2009-12-21

    We report on an approach to ultraviolet (UV) photolithography and direct writing where both the exposure pattern and dose are determined by a complementary metal oxide semiconductor (CMOS) controlled micro-pixellated light emitting diode array. The 370 nm UV light from a demonstrator 8 x 8 gallium nitride micro-pixel LED is projected onto photoresist covered substrates using two back-to-back microscope objectives, allowing controlled demagnification. In the present setup, the system is capable of delivering up to 8.8 W/cm2 per imaged pixel in circular spots of diameter approximately 8 microm. We show example structures written in positive as well as in negative photoresist. PMID:20052059

  12. Preliminary investigations of active pixel sensors in Nuclear Medicine imaging

    NASA Astrophysics Data System (ADS)

    Ott, Robert; Evans, Noel; Evans, Phil; Osmond, J.; Clark, A.; Turchetta, R.

    2009-06-01

    Three CMOS active pixel sensors have been investigated for their application to Nuclear Medicine imaging. Startracker with 525×525 25 μm square pixels has been coupled via a fibre optic stud to a 2 mm thick segmented CsI(Tl) crystal. Imaging tests were performed using 99mTc sources, which emit 140 keV gamma rays. The system was interfaced to a PC via FPGA-based DAQ and optical link enabling imaging rates of 10 f/s. System noise was measured to be >100e and it was shown that the majority of this noise was fixed pattern in nature. The intrinsic spatial resolution was measured to be ˜80 μm and the system spatial resolution measured with a slit was ˜450 μm. The second sensor, On Pixel Intelligent CMOS (OPIC), had 64×72 40 μm pixels and was used to evaluate noise characteristics and to develop a method of differentiation between fixed pattern and statistical noise. The third sensor, Vanilla, had 520×520 25 μm pixels and a measured system noise of ˜25e. This sensor was coupled directly to the segmented phosphor. Imaging results show that even at this lower level of noise the signal from 140 keV gamma rays is small as the light from the phosphor is spread over a large number of pixels. Suggestions for the 'ideal' sensor are made.

  13. An ultra-low power self-timed column-level ADC for a CMOS pixel sensor based vertex detector

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Wang, M.

    2014-11-01

    The International Large Detector (ILD) is a detector concept for the future linear collider experiment. The vertex detector is the key tool to achieve high precision measurements for flavor tagging, which puts stringent requirements on the CMOS pixel sensors. Due to the cooling systems which deteriorate the material budget and increase the multiple scattering, it is important to reduce the power consumption. This paper presents an ultra-low power self-timed column-level ADC for the CMOS pixel sensors, aiming to equip the outer layers of the vertex detector. The ADC was designed to operate in two modes (active and idle) adapted to the low hit density in the outer layers. The architecture employs an enhanced sample-and-hold circuit and a self-timed technique. The total power consumption with a 3-V supply is 225μW during idle mode, which is the most frequent situation. This value rises to 425μW in the case of the active mode. It occupies an area of 35 × 590μm2.

  14. 10000 pixels wide CMOS frame imager for earth observation from a HALE UAV

    NASA Astrophysics Data System (ADS)

    Delauré, B.; Livens, S.; Everaerts, J.; Kleihorst, R.; Schippers, Gert; de Wit, Yannick; Compiet, John; Banachowicz, Bartosz

    2009-09-01

    MEDUSA is the lightweight high resolution camera, designed to be operated from a solar-powered Unmanned Aerial Vehicle (UAV) flying at stratospheric altitudes. The instrument is a technology demonstrator within the Pegasus program and targets applications such as crisis management and cartography. A special wide swath CMOS imager has been developed by Cypress Semiconductor Cooperation Belgium to meet the specific sensor requirements of MEDUSA. The CMOS sensor has a stitched design comprising a panchromatic and color sensor on the same die. Each sensor consists of 10000*1200 square pixels (5.5μm size, novel 6T architecture) with micro-lenses. The exposure is performed by means of a high efficiency snapshot shutter. The sensor is able to operate at a rate of 30fps in full frame readout. Due to a novel pixel design, the sensor has low dark leakage of the memory elements (PSNL) and low parasitic light sensitivity (PLS). Still it maintains a relative high QE (Quantum efficiency) and a FF (fill factor) of over 65%. It features an MTF (Modulation Transfer Function) higher than 60% at Nyquist frequency in both X and Y directions The measured optical/electrical crosstalk (expressed as MTF) of this 5.5um pixel is state-of-the art. These properties makes it possible to acquire sharp images also in low-light conditions.

  15. Optical confinement methods for continued scaling of CMOS image sensor pixels.

    PubMed

    Fesenmaier, Christian C; Huo, Yijie; Catrysse, Peter B

    2008-12-01

    The pixels that make up CMOS image sensors have steadily decreased in size over the last decade. This scaling has two effects: first, the amount of light incident on each pixel decreases, making optical efficiency, i.e., the collection of each photon, more important. Second, diffraction comes into play when pixel size approaches the wavelength of visible light, resulting in increased spatial optical crosstalk. To address these two effects, we investigate and compare three methods for guiding incident light from the microlens down to the photodiode. Two of these techniques rely on total internal reflection (TIR) at the boundary between dielectric media of different refractive indices, while the third uses reflection at a metal-dielectric interface to confine the light. Simulations are performed using a finite-difference time-domain (FDTD) method on a realistic 1.75-mum pixel model for on-axis as well as angled incidence. We evaluate the optical efficiency and spatial crosstalk performance of these methods compared to a reference pixel and find significant (10%) improvement for the TIR designs with properly chosen parameters and nearly full spatial crosstalk elimination using metal to confine the light. We also show that these improvements are comparable to those achieved by thinning the image sensor stack. PMID:19065184

  16. High-voltage pixel detectors in commercial CMOS technologies for ATLAS, CLIC and Mu3e experiments

    NASA Astrophysics Data System (ADS)

    Perić, Ivan; Fischer, Peter; Kreidl, Christian; Hanh Nguyen, Hong; Augustin, Heiko; Berger, Niklaus; Kiehn, Moritz; Perrevoort, Ann-Kathrin; Schöning, André; Wiedner, Dirk; Feigl, Simon; Heim, Timon; Meng, Lingxin; Münstermann, Daniel; Benoit, Mathieu; Dannheim, Dominik; Bompard, Frederic; Breugnon, Patrick; Clemens, Jean-Claude; Fougeron, Denis; Liu, Jian; Pangaud, Patrick; Rozanov, Alexandre; Barbero, Marlon; Backhaus, Malte; Hügging, Fabian; Krüger, Hans; Lütticke, Florian; Mariñas, Carlos; Obermann, Theresa; Garcia-Sciveres, Maurice; Schwenker, Benjamin; Dierlamm, Alexander; La Rosa, Alessandro; Miucci, Antonio

    2013-12-01

    High-voltage particle detectors in commercial CMOS technologies are a detector family that allows implementation of low-cost, thin and radiation-tolerant detectors with a high time resolution. In the R/D phase of the development, a radiation tolerance of 1015 neq/cm2, nearly 100% detection efficiency and a spatial resolution of about 3 μm were demonstrated. Since 2011 the HV detectors have first applications: the technology is presently the main option for the pixel detector of the planned Mu3e experiment at PSI (Switzerland). Several prototype sensors have been designed in a standard 180 nm HV CMOS process and successfully tested. Thanks to its high radiation tolerance, the HV detectors are also seen at CERN as a promising alternative to the standard options for ATLAS upgrade and CLIC. In order to test the concept, within ATLAS upgrade R/D, we are currently exploring an active pixel detector demonstrator HV2FEI4; also implemented in the 180 nm HV process.

  17. A high speed, low power consumption LVDS interface for CMOS pixel sensors

    NASA Astrophysics Data System (ADS)

    Shi, Zhan; Tang, Zhenan; Tian, Yong; Pham, Hung; Valin, Isabelle; Jaaskelainen, Kimmo

    2015-01-01

    The use of CMOS Pixel Sensors (CPSs) offers a promising approach to the design of vertex detectors in High Energy Physics (HEP) experiments. As the CPS equipping the upgraded Solenoidal Tracker at RHIC (STAR) pixel detector, ULTIMATE perfectly illustrates the potential of CPSs for HEP applications. However, further development of CPSs with respect to readout speed is required to fulfill the readout time requirement of the next generation HEP detectors, such as the upgrade of A Large Ion Collider Experiment (ALICE) Inner Tracking System (ITS), the International Linear Collider (ILC), and the Compressed Baryonic Matter (CBM) vertex detectors. One actual limitation of CPSs is related to the speed of the Low-Voltage Differential Signaling (LVDS) circuitry implementing the interface between the sensor and the Data Acquisition (DAQ) system. To improve the transmission rate while keeping the power consumption at a low level, a source termination technique and a special current comparator were adopted for the LVDS driver and receiver, respectively. Moreover, hardening techniques are used. The circuitry was designed and submitted for fabrication in a 0.18-μm CMOS Image Sensor (CIS) process at the end of 2011. The test results indicated that the LVDS driver and receiver can operate properly at the data rate of 1.2 Gb/s with power consumption of 19.6 mW.

  18. Active-Pixel Image Sensor With Analog-To-Digital Converters

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R.; Mendis, Sunetra K.; Pain, Bedabrata; Nixon, Robert H.

    1995-01-01

    Proposed single-chip integrated-circuit image sensor contains 128 x 128 array of active pixel sensors at 50-micrometer pitch. Output terminals of all pixels in each given column connected to analog-to-digital (A/D) converter located at bottom of column. Pixels scanned in semiparallel fashion, one row at time; during time allocated to scanning row, outputs of all active pixel sensors in row fed to respective A/D converters. Design of chip based on complementary metal oxide semiconductor (CMOS) technology, and individual circuit elements fabricated according to 2-micrometer CMOS design rules. Active pixel sensors designed to operate at video rate of 30 frames/second, even at low light levels. A/D scheme based on first-order Sigma-Delta modulation.

  19. A novel pixel design with hybrid type isolation scheme for low dark current in CMOS image sensor

    NASA Astrophysics Data System (ADS)

    Choi, Sung Ho; Kim, Yi Tae; Oh, Min Seok; Park, Young Hwan; Cho, Jeong Jin; Jang, Young Heub; Han, Hyung Jun; Choi, Jong Won; Park, Ho Woo; Jung, Sang Il; Oh, Hoon Sang; Ahn, Jung Chak; Goto, Hiroshige; Choi, Chi Young; Roh, Yonghan

    2013-02-01

    New isolation scheme for CMOS image sensor pixel is proposed and its improved dark current performance is reported. It is well known that shallow trench isolation (STI) is one of major sources of dark current in imager pixel due to the existence of interfacial defects at STI/Si interface. On the account STI-free structure over the whole pixel area was previously reported for reducing dark current. As the size of pixel pitch is shrunk, however, it becomes increasingly difficult to isolate in-pixel transistors electrically without STI. In this work, we implemented hybrid type isolation scheme of removing STI around photodiode to suppress the dark current and remaining STI near transistors to guarantee the electrical isolation of transistors in pixel. It was successfully achieved that the dark current was significantly reduced by removing the STI around the photodiode together with normal operation of in-pixel transistors.

  20. CMOS image sensor with lateral electric field modulation pixels for fluorescence lifetime imaging with sub-nanosecond time response

    NASA Astrophysics Data System (ADS)

    Li, Zhuo; Seo, Min-Woong; Kagawa, Keiichiro; Yasutomi, Keita; Kawahito, Shoji

    2016-04-01

    This paper presents the design and implementation of a time-resolved CMOS image sensor with a high-speed lateral electric field modulation (LEFM) gating structure for time domain fluorescence lifetime measurement. Time-windowed signal charge can be transferred from a pinned photodiode (PPD) to a pinned storage diode (PSD) by turning on a pair of transfer gates, which are situated beside the channel. Unwanted signal charge can be drained from the PPD to the drain by turning on another pair of gates. The pixel array contains 512 (V) × 310 (H) pixels with 5.6 × 5.6 µm2 pixel size. The imager chip was fabricated using 0.11 µm CMOS image sensor process technology. The prototype sensor has a time response of 150 ps at 374 nm. The fill factor of the pixels is 5.6%. The usefulness of the prototype sensor is demonstrated for fluorescence lifetime imaging through simulation and measurement results.

  1. Active Pixel Sensor Characterization for the STAR Detector

    NASA Astrophysics Data System (ADS)

    King, Jake

    2004-10-01

    The STAR collaboration is studying matter at high temperatures and densities. If a significant improvement to the measurement of particle trajectories can be made, charmed mesons that decay away from the primary collision point could be identified. To achieve this goal, STAR is building a vertex detector consisting of a new technology Â- active pixel sensors. (APS) An APS is an implementation of standard CMOS technology in which each pixel has a photodiode directly above the epitaxial layer. Incident particles produce electron-hole pairs in the epitaxial layer, and these electrons accumulate on the photodiode. Charge from the photodiode is digitized to identify the position of the incident particle. It is important to characterize the signal to noise, readout time, and resolution on several different pixel sizes so that the vertex detector can be optimized for cost and speed. Larger pixels result in a faster data acquisition, while smaller pixels have better resolution. We will present studies of 5, 10, 20 and 30μm square pixel geometries that measure charge distribution and collection. We will also display the results of using a field emission scanning electron microscope with energies from 1 to 30 keV. This tool has the potential to probe regions of the APS integrated circuit and contribute to understanding its properties.

  2. An ultra-low power CMOS oscillating pixel array for retina implantation

    NASA Astrophysics Data System (ADS)

    Sun, Kang-Ming; Yuan, Xiang-Hui; Meng, Li-Ya; Rao, Cheng

    2010-07-01

    A light-controlled oscillating array for retina prosthesis is presented. The unique advantage of the circuit is that it has a lower voltage and ultra-low power consumption. And it has some other features as below: it is applicable to the natural light illumination and each pixel is an independent oscillator whose frequency is proportional to the intensity of the incident light. The fundamental characteristics of the circuit are analyzed. It is fabricated with a standard 0.6 μm CMOS technology. The experimental results indicate that the proposed circuit can be used for retina implantation, taking the place of the suffered photoreceptor in the retina of the blind and partially recovering the blind’s eyesight.

  3. Reset noise suppression in two-dimensional CMOS photodiode pixels through column-based feedback-reset

    NASA Technical Reports Server (NTRS)

    Pain, B.; Cunningham, T. J.; Hancock, B.; Yang, G.; Seshadri, S.; Ortiz, M.

    2002-01-01

    We present new CMOS photodiode imager pixel with ultra-low read noise through on-chip suppression of reset noise via column-based feedback circuitry. The noise reduction is achieved without introducing any image lag, and with insignificant reduction in quantum efficiency and full well.

  4. Comparison of CCD, CMOS and Hybrid Pixel x-ray detectors: detection principle and data quality

    NASA Astrophysics Data System (ADS)

    Allé, P.; Wenger, E.; Dahaoui, S.; Schaniel, D.; Lecomte, C.

    2016-06-01

    We compare, from a crystallographic point of view, the data quality obtained using laboratory x-ray diffractometers equipped with a Molybdenum micro-source using different detector types: CCD, CMOS and XPAD hybrid pixel. First we give an overview of the working principle of these different detector types with a focus on their principal differences and their impact on the data quality. Then, using the example of an organic crystal, a comparison between the detector systems concerning the raw data statistics, the refinement agreement factors, the deformation electron density maps, and the residual density after multipolar refinement is presented. It is found that the data quality obtained with the XPAD detector is the best, even though the detection efficiency at the Mo energy (17.5 keV) is only 37% due to the Si-sensor layer thickness of 300 μm. Finally, we discuss the latest x-ray detector developments with an emphasis on the sensor material, where replacing Si by another material such as GaAs would yield detection efficiencies close to 100%, up to energies of 40 keV for hybrid pixel detectors.

  5. Design of the low area monotonic trim DAC in 40 nm CMOS technology for pixel readout chips

    NASA Astrophysics Data System (ADS)

    Drozd, A.; Szczygiel, R.; Maj, P.; Satlawa, T.; Grybos, P.

    2014-12-01

    The recent research in hybrid pixel detectors working in single photon counting mode focuses on nanometer or 3D technologies which allow making pixels smaller and implementing more complex solutions in each of the pixels. Usually single pixel in readout electronics for X-ray detection comprises of charge amplifier, shaper and discriminator that allow classification of events occurring at the detector as true or false hits by comparing amplitude of the signal obtained with threshold voltage, which minimizes the influence of noise effects. However, making the pixel size smaller often causes problems with pixel to pixel uniformity and additional effects like charge sharing become more visible. To improve channel-to-channel uniformity or implement an algorithm for charge sharing effect minimization, small area trimming DACs working in each pixel independently are necessary. However, meeting the requirement of small area often results in poor linearity and even non-monotonicity. In this paper we present a novel low-area thermometer coded 6-bit DAC implemented in 40 nm CMOS technology. Monte Carlo simulations were performed on the described design proving that under all conditions designed DAC is inherently monotonic. Presented DAC was implemented in the prototype readout chip with 432 pixels working in single photon counting mode, with two trimming DACs in each pixel. Each DAC occupies the area of 8 μm × 18.5 μm. Measurements and chips' tests were performed to obtain reliable statistical results.

  6. Digital pixel CMOS focal plane array with on-chip multiply accumulate units for low-latency image processing

    NASA Astrophysics Data System (ADS)

    Little, Jeffrey W.; Tyrrell, Brian M.; D'Onofrio, Richard; Berger, Paul J.; Fernandez-Cull, Christy

    2014-06-01

    A digital pixel CMOS focal plane array has been developed to enable low latency implementations of image processing systems such as centroid trackers, Shack-Hartman wavefront sensors, and Fitts correlation trackers through the use of in-pixel digital signal processing (DSP) and generic parallel pipelined multiply accumulate (MAC) units. Light intensity digitization occurs at the pixel level, enabling in-pixel DSP and noiseless data transfer from the pixel array to the peripheral processing units. The pipelined processing of row and column image data prior to off chip readout reduces the required output bandwidth of the image sensor, thus reducing the latency of computations necessary to implement various image processing systems. Data volume reductions of over 80% lead to sub 10μs latency for completing various tracking and sensor algorithms. This paper details the architecture of the pixel-processing imager (PPI) and presents some initial results from a prototype device fabricated in a standard 65nm CMOS process hybridized to a commercial off-the-shelf short-wave infrared (SWIR) detector array.

  7. A Low-Noise CMOS THz Imager Based on Source Modulation and an In-Pixel High-Q Passive Switched-Capacitor N-Path Filter.

    PubMed

    Boukhayma, Assim; Dupret, Antoine; Rostaing, Jean-Pierre; Enz, Christian

    2016-01-01

    This paper presents the first low noise complementary metal oxide semiconductor (CMOS) deletedCMOS terahertz (THz) imager based on source modulation and in-pixel high-Q filtering. The 31 × 31 focal plane array has been fully integrated in a 0 . 13 μ m standard CMOS process. The sensitivity has been improved significantly by modulating the active THz source that lights the scene and performing on-chip high-Q filtering. Each pixel encompass a broadband bow tie antenna coupled to an N-type metal-oxide-semiconductor (NMOS) detector that shifts the THz radiation, a low noise adjustable gain amplifier and a high-Q filter centered at the modulation frequency. The filter is based on a passive switched-capacitor (SC) N-path filter combined with a continuous-time broad-band Gm-C filter. A simplified analysis that helps in designing and tuning the passive SC N-path filter is provided. The characterization of the readout chain shows that a Q factor of 100 has been achieved for the filter with a good matching between the analytical calculation and the measurement results. An input-referred noise of 0 . 2 μ V RMS has been measured. Characterization of the chip with different THz wavelengths confirms the broadband feature of the antenna and shows that this THz imager reaches a total noise equivalent power of 0 . 6 nW at 270 GHz and 0 . 8 nW at 600 GHz. PMID:26950131

  8. Laser Doppler blood flow imaging with a 64×64 pixel full custom CMOS sensor

    NASA Astrophysics Data System (ADS)

    He, D.; Nguyen, H. C.; Hayes-Gill, B. R.; Zhu, Y.; Crowe, J. A.; Morgan, S. P.; Clough, G. F.; Gill, C. A.

    2011-03-01

    Full field laser Doppler perfusion imaging offers advantages over scanning laser Doppler imaging as the effects of movement artifacts are reduced. The increased frame rate allows rapid changes in blood flow to be imaged. A custom made CMOS sensor offers several advantages over commercial cameras as the design can be optimized to the detected signals. For example, laser Doppler signals are known to have a bandwidth from DC up to ~20KHz and be of a low modulation depth. Therefore a design that can amplify the AC component and have a sampling rate and an antialiasing filter appropriate to the signal bandwidth would be beneficial. An additional advantage of custom made sensors is that on-chip processing of blood flow allows the data bottleneck that exists between the photo-detector array and processing electronics to be overcome, as the processed data can be read out from the image sensor to a PC or display at a low data rate. A fully integrated 64x64 pixel array for imaging blood flow is presented. On-chip analog signal processing is used to amplify the AC component, normalize the AC signal by the DC light intensity and provide anti-aliasing. On-chip digital signal processing is used to implement the filters required to calculate blood flow. The imaging array has been incorporated into a device that has been used in a clinical setting. Results are presented demonstrating changes in blood flow in occlusion and release tests.

  9. MISTRAL & ASTRAL: two CMOS Pixel Sensor architectures suited to the Inner Tracking System of the ALICE experiment

    NASA Astrophysics Data System (ADS)

    Morel, F.; Hu-Guo, C.; Bertolone, G.; Claus, G.; Colledani, C.; Dorokhov, A.; Dozière, G.; Dulinski, W.; Fang, X.; Goffe, M.; Himmi, A.; Jaaskelainen, K.; Senyukov, S.; Specht, M.; Szelezniak, M.; Pham, H.; Valin, I.; Wang, T.; Winter, M.

    2014-01-01

    A detector, equipped with 50 μm thin CMOS Pixel Sensors (CPS), is being designed for the upgrade of the Inner Tracking System (ITS) of the ALICE experiment at LHC. Two CPS flavours, MISTRAL and ASTRAL, are being developed at IPHC aiming to meet the requirements of the ITS upgrade. The first is derived from the MIMOSA28 sensor designed for the STAR-PXL detector. The second integrates a discriminator in each pixel to improve the readout speed and power consumption. This paper will describe in details the sensor development and show some preliminary test results.

  10. The detection of single electrons using a Micromegas gas amplification and a MediPix2 CMOS pixel readout

    NASA Astrophysics Data System (ADS)

    Fornaini, A.; Campbell, M.; Chefdeville, M.; Colas, P.; Colijn, A. P.; van der Graaf, H.; Giomataris, Y.; Heijne, E. H. M.; Kluit, P.; Llopart, X.; Schmitz, J.; Timmermans, J.; Visschers, J. L.

    2005-07-01

    By placing a Micromegas gas gain grid on top of a CMOS pixel readout circuit (MediPix2), we developed a device which acts as a pixel-segmented direct anode in gas-filled detectors. With a He/Isobutane 80/20 mixture (capable of achieving gas gain factors up to 20×103) and employing a drift length of 15 mm, signals from radioactive sources and cosmic radiation were measured. Single primary electrons originating from the passage of cosmic muons through the gas volume were detected with an efficiency higher than 90%.

  11. First measurement of the in-pixel electron multiplying with a standard imaging CMOS technology: Study of the EMCMOS concept

    NASA Astrophysics Data System (ADS)

    Brugière, Timothée; Mayer, Fréderic; Fereyre, Pierre; Guérin, Cyrille; Dominjon, Agnés; Barbier, Rémi

    2015-07-01

    Scientific low light imaging devices benefit today from designs for pushing the mean noise to the single electron level. When readout noise reduction reaches its limit, signal-to-noise ratio improvement can be driven by an electron multiplication process, driven by impact ionization, before adding the readout noises. This concept already implemented in CCD structures using extra-pixel shift registers can today be integrated inside each pixel in CMOS technology. The EBCMOS group at IPNL is in charge of the characterization of new prototypes developed by E2V using this concept: the electron multiplying CMOS (EMCMOS). The CMOS technology enables electron multiplication inside the photodiode itself, and thus, an overlap of the charge integration and multiplication. A new modeling has been developed to describe the output signal mean and variance after the impact ionization process in such a case. In this paper the feasibility of impact ionization process inside a 8 μm-pitch pixel is demonstrated. The new modeling is also validated by data and a value of 0.32% is obtained for the impact ionization parameter α with an electric field intensity of 24 V / μm.

  12. Monolithic Active-Pixel Infrared Sensors

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R.; Cunningham, Thomas J.; Krabach, Timothy N.; Staller, Craig O.

    1995-01-01

    Monolithic arrays of active-pixel junction field-effect (JFET) devices made from InGaAs proposed for use as imaging sensors sensitive to light in visible and short-wavelength infrared parts of electromagnetic spectrum. Each pixel of such array comprises photodetector monolithically integrated with JFET output-amplifier circuit of source-follower type - structure similar to charge-coupled device (CCD). Sizes of instruments reduced because large cooling systems not needed.

  13. Active Pixel Sensors: Are CCD's Dinosaurs?

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R.

    1993-01-01

    Charge-coupled devices (CCD's) are presently the technology of choice for most imaging applications. In the 23 years since their invention in 1970, they have evolved to a sophisticated level of performance. However, as with all technologies, we can be certain that they will be supplanted someday. In this paper, the Active Pixel Sensor (APS) technology is explored as a possible successor to the CCD. An active pixel is defined as a detector array technology that has at least one active transistor within the pixel unit cell. The APS eliminates the need for nearly perfect charge transfer -- the Achilles' heel of CCDs. This perfect charge transfer makes CCD's radiation 'soft,' difficult to use under low light conditions, difficult to manufacture in large array sizes, difficult to integrate with on-chip electronics, difficult to use at low temperatures, difficult to use at high frame rates, and difficult to manufacture in non-silicon materials that extend wavelength response.

  14. A Stimulated Raman Scattering CMOS Pixel Using a High-Speed Charge Modulator and Lock-in Amplifier.

    PubMed

    Lioe, De Xing; Mars, Kamel; Kawahito, Shoji; Yasutomi, Keita; Kagawa, Keiichiro; Yamada, Takahiro; Hashimoto, Mamoru

    2016-01-01

    A complementary metal-oxide semiconductor (CMOS) lock-in pixel to observe stimulated Raman scattering (SRS) using a high speed lateral electric field modulator (LEFM) for photo-generated charges and in-pixel readout circuits is presented. An effective SRS signal generated after the SRS process is very small and needs to be extracted from an extremely large offset due to a probing laser signal. In order to suppress the offset components while amplifying high-frequency modulated small SRS signal components, the lock-in pixel uses a high-speed LEFM for demodulating the SRS signal, resistor-capacitor low-pass filter (RC-LPF) and switched-capacitor (SC) integrator with a fully CMOS differential amplifier. AC (modulated) components remained in the RC-LPF outputs are eliminated by the phase-adjusted sampling with the SC integrator and the demodulated DC (unmodulated) components due to the SRS signal are integrated over many samples in the SC integrator. In order to suppress further the residual offset and the low frequency noise (1/f noise) components, a double modulation technique is introduced in the SRS signal measurements, where the phase of high-frequency modulated laser beam before irradiation of a specimen is modulated at an intermediate frequency and the demodulation is done at the lock-in pixel output. A prototype chip for characterizing the SRS lock-in pixel is implemented and a successful operation is demonstrated. The reduction effects of residual offset and 1/f noise components are confirmed by the measurements. A ratio of the detected small SRS to offset a signal of less than 10(-)⁵ is experimentally demonstrated, and the SRS spectrum of a Benzonitrile sample is successfully observed. PMID:27089339

  15. A Stimulated Raman Scattering CMOS Pixel Using a High-Speed Charge Modulator and Lock-in Amplifier

    PubMed Central

    Lioe, De Xing; Mars, Kamel; Kawahito, Shoji; Yasutomi, Keita; Kagawa, Keiichiro; Yamada, Takahiro; Hashimoto, Mamoru

    2016-01-01

    A complementary metal-oxide semiconductor (CMOS) lock-in pixel to observe stimulated Raman scattering (SRS) using a high speed lateral electric field modulator (LEFM) for photo-generated charges and in-pixel readout circuits is presented. An effective SRS signal generated after the SRS process is very small and needs to be extracted from an extremely large offset due to a probing laser signal. In order to suppress the offset components while amplifying high-frequency modulated small SRS signal components, the lock-in pixel uses a high-speed LEFM for demodulating the SRS signal, resistor-capacitor low-pass filter (RC-LPF) and switched-capacitor (SC) integrator with a fully CMOS differential amplifier. AC (modulated) components remained in the RC-LPF outputs are eliminated by the phase-adjusted sampling with the SC integrator and the demodulated DC (unmodulated) components due to the SRS signal are integrated over many samples in the SC integrator. In order to suppress further the residual offset and the low frequency noise (1/f noise) components, a double modulation technique is introduced in the SRS signal measurements, where the phase of high-frequency modulated laser beam before irradiation of a specimen is modulated at an intermediate frequency and the demodulation is done at the lock-in pixel output. A prototype chip for characterizing the SRS lock-in pixel is implemented and a successful operation is demonstrated. The reduction effects of residual offset and 1/f noise components are confirmed by the measurements. A ratio of the detected small SRS to offset a signal of less than 10−5 is experimentally demonstrated, and the SRS spectrum of a Benzonitrile sample is successfully observed. PMID:27089339

  16. MONOLITHIC ACTIVE PIXEL MATRIX WITH BINARY COUNTERS IN AN SOI PROCESS.

    SciTech Connect

    DUPTUCH,G.; YAREMA, R.

    2007-06-07

    The design of a Prototype monolithic active pixel matrix, designed in a 0.15 {micro}m CMOS SOI Process, is presented. The process allowed connection between the electronics and the silicon volume under the layer of buried oxide (BOX). The small size vias traversing through the BOX and implantation of small p-type islands in the n-type bulk result in a monolithic imager. During the acquisition time, all pixels register individual radiation events incrementing the counters. The counting rate is up to 1 MHz per pixel. The contents of counters are shifted out during the readout phase. The designed prototype is an array of 64 x 64 pixels and the pixel size is 26 x 26 {micro}m{sup 2}.

  17. Hot pixel generation in active pixel sensors: dosimetric and micro-dosimetric response

    NASA Technical Reports Server (NTRS)

    Scheick, Leif; Novak, Frank

    2003-01-01

    The dosimetric response of an active pixel sensor is analyzed. heavy ions are seen to damage the pixel in much the same way as gamma radiation. The probability of a hot pixel is seen to exhibit behavior that is not typical with other microdose effects.

  18. Efficiency enhancement in a backside illuminated 1.12 μm pixel CMOS image sensor via parabolic color filters.

    PubMed

    Lee, Jong-Kwon; Kim, Ahreum; Kang, Dong-Wan; Lee, Byung Yang

    2016-07-11

    The shrinkage of pixel size down to sub-2 μm in high-resolution CMOS image sensors (CISs) results in degraded efficiency and increased crosstalk. The backside illumination technology can increase the efficiency, but the crosstalk still remains an critical issue to improve the image quality of the CIS devices. In this paper, by adopting a parabolic color filter (P-CF), we demonstrate efficiency enhancement without any noticeable change in optical crosstalk of a backside illuminated 1.12 μm pixel CIS with deep-trench-isolation structure. To identify the observed results, we have investigated the effect of radius of curvature (r) of the P-CF on the efficiency and optical crosstalk of the CIS by performing an electromagnetic analysis. As the r of P-CF becomes equal to (or half) that of the microlens, the efficiencies of the B-, G-, and R-pixels increase by a factor of 14.1% (20.3%), 9.8% (15.3%), and 15.0% (15.7%) with respect to the flat CF cases without any noticeable crosstalk change. Also, as the incident angle increases up to 30°, the angular dependence of the efficiency and crosstalk significantly decreases by utilizing the P-CF in the CIS. Meanwhile, further reduction of r severely increases the optical crosstalk due to the increased diffraction effect, which has been confirmed with the simulated electric-field intensity distribution inside the devices. PMID:27410872

  19. Active pixel sensor with intra-pixel charge transfer

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R. (Inventor); Mendis, Sunetra (Inventor); Kemeny, Sabrina E. (Inventor)

    1995-01-01

    An imaging device formed as a monolithic complementary metal oxide semiconductor integrated circuit in an industry standard complementary metal oxide semiconductor process, the integrated circuit including a focal plane array of pixel cells, each one of the cells including a photogate overlying the substrate for accumulating photo-generated charge in an underlying portion of the substrate, a readout circuit including at least an output field effect transistor formed in the substrate, and a charge coupled device section formed on the substrate adjacent the photogate having a sensing node connected to the output transistor and at least one charge coupled device stage for transferring charge from the underlying portion of the substrate to the sensing node.

  20. Active pixel sensor with intra-pixel charge transfer

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R. (Inventor); Mendis, Sunetra (Inventor); Kemeny, Sabrina E. (Inventor)

    2003-01-01

    An imaging device formed as a monolithic complementary metal oxide semiconductor integrated circuit in an industry standard complementary metal oxide semiconductor process, the integrated circuit including a focal plane array of pixel cells, each one of the cells including a photogate overlying the substrate for accumulating photo-generated charge in an underlying portion of the substrate, a readout circuit including at least an output field effect transistor formed in the substrate, and a charge coupled device section formed on the substrate adjacent the photogate having a sensing node connected to the output transistor and at least one charge coupled device stage for transferring charge from the underlying portion of the substrate to the sensing node.

  1. Active pixel sensor with intra-pixel charge transfer

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R. (Inventor); Mendis, Sunetra (Inventor); Kemeny, Sabrina E. (Inventor)

    2004-01-01

    An imaging device formed as a monolithic complementary metal oxide semiconductor integrated circuit in an industry standard complementary metal oxide semiconductor process, the integrated circuit including a focal plane array of pixel cells, each one of the cells including a photogate overlying the substrate for accumulating photo-generated charge in an underlying portion of the substrate, a readout circuit including at least an output field effect transistor formed in the substrate, and a charge coupled device section formed on the substrate adjacent the photogate having a sensing node connected to the output transistor and at least one charge coupled device stage for transferring charge from the underlying portion of the substrate to the sensing node.

  2. ALPIDE, the Monolithic Active Pixel Sensor for the ALICE ITS upgrade

    NASA Astrophysics Data System (ADS)

    Mager, M.

    2016-07-01

    A new 10 m2 inner tracking system based on seven concentric layers of Monolithic Active Pixel Sensors will be installed in the ALICE experiment during the second long shutdown of LHC in 2019-2020. The monolithic pixel sensors will be fabricated in the 180 nm CMOS Imaging Sensor process of TowerJazz. The ALPIDE design takes full advantage of a particular process feature, the deep p-well, which allows for full CMOS circuitry within the pixel matrix, while at the same time retaining the full charge collection efficiency. Together with the small feature size and the availability of six metal layers, this allowed a continuously active low-power front-end to be placed into each pixel and an in-matrix sparsification circuit to be used that sends only the addresses of hit pixels to the periphery. This approach led to a power consumption of less than 40 mWcm-2, a spatial resolution of around 5 μm, a peaking time of around 2 μs, while being radiation hard to some 1013 1 MeVneq /cm2, fulfilling or exceeding the ALICE requirements. Over the last years of R & D, several prototype circuits have been used to verify radiation hardness, and to optimize pixel geometry and in-pixel front-end circuitry. The positive results led to a submission of full-scale (3 cm×1.5 cm) sensor prototypes in 2014. They are being characterized in a comprehensive campaign that also involves several irradiation and beam tests. A summary of the results obtained and prospects towards the final sensor to instrument the ALICE Inner Tracking System are given.

  3. A Low-Noise CMOS THz Imager Based on Source Modulation and an In-Pixel High-Q Passive Switched-Capacitor N-Path Filter

    PubMed Central

    Boukhayma, Assim; Dupret, Antoine; Rostaing, Jean-Pierre; Enz, Christian

    2016-01-01

    This paper presents the first low noise complementary metal oxide semiconductor (CMOS) terahertz (THz) imager based on source modulation and in-pixel high-Q filtering. The 31×31 focal plane array has been fully integrated in a 0.13μm standard CMOS process. The sensitivity has been improved significantly by modulating the active THz source that lights the scene and performing on-chip high-Q filtering. Each pixel encompass a broadband bow tie antenna coupled to an N-type metal-oxide-semiconductor (NMOS) detector that shifts the THz radiation, a low noise adjustable gain amplifier and a high-Q filter centered at the modulation frequency. The filter is based on a passive switched-capacitor (SC) N-path filter combined with a continuous-time broad-band Gm-C filter. A simplified analysis that helps in designing and tuning the passive SC N-path filter is provided. The characterization of the readout chain shows that a Q factor of 100 has been achieved for the filter with a good matching between the analytical calculation and the measurement results. An input-referred noise of 0.2μV RMS has been measured. Characterization of the chip with different THz wavelengths confirms the broadband feature of the antenna and shows that this THz imager reaches a total noise equivalent power of 0.6 nW at 270 GHz and 0.8 nW at 600 GHz. PMID:26950131

  4. Heavy Ion Transient Characterization of a Photobit Hardened-by-Design Active Pixel Sensor Array

    NASA Technical Reports Server (NTRS)

    Marshall, Paul W.; Byers, Wheaton B.; Conger, Christopher; Eid, El-Sayed; Gee, George; Jones, Michael R.; Marshall, Cheryl J.; Reed, Robert; Pickel, Jim; Kniffin, Scott

    2002-01-01

    This paper presents heavy ion data on the single event transient (SET) response of a Photobit active pixel sensor (APS) four quadrant test chip with different radiation tolerant designs in a standard 0.35 micron CMOS process. The physical design techniques of enclosed geometry and P-channel guard rings are used to design the four N-type active photodiode pixels as described in a previous paper. Argon transient measurements on the 256 x 256 chip array as a function of incident angle show a significant variation in the amount of charge collected as well as the charge spreading dependent on the pixel type. The results are correlated with processing and design information provided by Photobit. In addition, there is a large degree of statistical variability between individual ion strikes. No latch-up is observed up to an LET of 106 MeV/mg/sq cm.

  5. Active pixel sensor array with electronic shuttering

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R. (Inventor)

    2002-01-01

    An active pixel cell includes electronic shuttering capability. The cell can be shuttered to prevent additional charge accumulation. One mode transfers the current charge to a storage node that is blocked against accumulation of optical radiation. The charge is sampled from a floating node. Since the charge is stored, the node can be sampled at the beginning and the end of every cycle. Another aspect allows charge to spill out of the well whenever the charge amount gets higher than some amount, thereby providing anti blooming.

  6. CMOS active pixel sensor type imaging system on a chip

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R. (Inventor); Nixon, Robert (Inventor)

    2011-01-01

    A single chip camera which includes an .[.intergrated.]. .Iadd.integrated .Iaddend.image acquisition portion and control portion and which has double sampling/noise reduction capabilities thereon. Part of the .[.intergrated.]. .Iadd.integrated .Iaddend.structure reduces the noise that is picked up during imaging.

  7. Characterisation of a PERCIVAL monolithic active pixel prototype using synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Correa, J.; Bayer, M.; Göttlicher, P.; Lange, S.; Marras, A.; Niemann, M.; Reza, S.; Shevyakov, I.; Smoljanin, S.; Tennert, M.; Xia, Q.; Viti, M.; Wunderer, C. B.; Zimmer, M.; Dipayan, D.; Guerrini, N.; Marsh, B.; Sedgwick, I.; Turchetta, R.; Cautero, G.; Giuressi, D.; Khromova, A.; Pinaroli, G.; Menk, R.; Stebel, L.; Fan, R.; Marchal, J.; Pedersen, U.; Rees, N.; Steadman, P.; Sussmuth, M.; Tartoni, N.; Yousef, H.; Hyun, H. J.; Kim, K.; Rah, S.; Graafsma, H.

    2016-02-01

    PERCIVAL ("Pixelated Energy Resolving CMOS Imager, Versatile And Large") is a monolithic active pixel sensor (MAPS) based on CMOS technology. Is being developed by DESY, RAL/STFC, Elettra, DLS, and PAL to address the various requirements of detectors at synchrotron radiation sources and Free Electron Lasers (FELs) in the soft X-ray regime. These requirements include high frame rates and FELs base-rate compatibility, large dynamic range, single-photon counting capability with low probability of false positives, high quantum efficiency (QE), and (multi-)megapixel arrangements with good spatial resolution. Small-scale back-side-illuminated (BSI) prototype systems are undergoing detailed testing with X-rays and optical photons, in preparation of submission of a larger sensor. A first BSI processed prototype was tested in 2014 and a preliminary result—first detection of 350eV photons with some pixel types of PERCIVAL—reported at this meeting a year ago. Subsequent more detailed analysis revealed a very low QE and pointed to contamination as a possible cause. In the past year, BSI-processed chips on two more wafers were tested and their response to soft X-ray evaluated. We report here the improved charge collection efficiency (CCE) of different PERCIVAL pixel types for 400eV soft X-rays together with Airy patterns, response to a flat field, and noise performance for such a newly BSI-processed prototype sensor.

  8. PIXEL 2010 - A Résumé

    NASA Astrophysics Data System (ADS)

    Wermes, N.

    2011-09-01

    The Pixel 2010 conference focused on semiconductor pixel detectors for particle tracking/vertexing as well as for imaging, in particular for synchrotron light sources and XFELs. The big LHC hybrid pixel detectors have impressively started showing their capabilities. X-ray imaging detectors, also using the hybrid pixel technology, have greatly advanced the experimental possibilities for diffraction experiments. Monolithic or semi-monolithic devices like CMOS active pixels and DEPFET pixels have now reached a state such that complete vertex detectors for RHIC and superKEKB are being built with these technologies. Finally, new advances towards fully monolithic active pixel detectors, featuring full CMOS electronics merged with efficient signal charge collection, exploiting standard CMOS technologies, SOI and/or 3D integration, show the path for the future. This résumé attempts to extract the main statements of the results and developments presented at this conference.

  9. A 256 pixel magnetoresistive biosensor microarray in 0.18μm CMOS

    PubMed Central

    Hall, Drew A.; Gaster, Richard S.; Makinwa, Kofi; Wang, Shan X.; Murmann, Boris

    2014-01-01

    Magnetic nanotechnologies have shown significant potential in several areas of nanomedicine such as imaging, therapeutics, and early disease detection. Giant magnetoresistive spin-valve (GMR SV) sensors coupled with magnetic nanotags (MNTs) possess great promise as ultra-sensitive biosensors for diagnostics. We report an integrated sensor interface for an array of 256 GMR SV biosensors designed in 0.18 μm CMOS. Arranged like an imager, each of the 16 column level readout channels contains an analog front- end and a compact ΣΔ modulator (0.054 mm2) with 84 dB of dynamic range and an input referred noise of 49 nT/√Hz. Performance is demonstrated through detection of an ovarian cancer biomarker, secretory leukocyte peptidase inhibitor (SLPI), spiked at concentrations as low as 10 fM. This system is designed as a replacement for optical protein microarrays while also providing real-time kinetics monitoring. PMID:24761029

  10. High-sensitivity active pixel sensor with variable threshold photodetector

    NASA Astrophysics Data System (ADS)

    Jo, Sung-Hyun; Bae, Myunghan; Choi, Byoung-Soo; Lyu, Hong-Kun; Shin, Jang-Kyoo

    2015-05-01

    A novel high-sensitivity active pixel sensor (APS) with a variable threshold photodetector has been presented and for the first time, a simple SPICE model for the variable threshold photodetector is presented. Its SPICE model is in good agreement with measurements and is more simpler than the conventional model. The proposed APS has a gate/body-tied PMOSFET-type photodetector with an overlapping control gate that makes it possible to control the sensitivity of the proposed APS. It is a hybrid device composed of a metal-oxide-semiconductor field-effect transistor (MOSFET), a lateral bipolar junction transistor (BJT) and a vertical BJT. Using sufficient overlapping control gate bias to operate the MOSFET in inversion mode, the variable threshold photodetector allows for increasing the photocurrent gain by 105 at low light intensities when the control gate bias is -3 V. Thus, the proposed APS with a variable threshold photodetector has better low-light-level sensitivity than the conventional APS operating mode, and it has a variable sensitivity which is determined by the control gate bias. The proposed sensor has been fabricated by using 0.35 μm 2-poly 4-metal standard complementary MOS (CMOS) process and its characteristics have been evaluated.

  11. Direct reading of charge multipliers with a self-triggering CMOS analog chip with 105 k pixels at 50 μm pitch

    NASA Astrophysics Data System (ADS)

    Bellazzini, R.; Spandre, G.; Minuti, M.; Baldini, L.; Brez, A.; Cavalca, F.; Latronico, L.; Omodei, N.; Massai, M. M.; Sgro', C.; Costa, E.; Soffitta, P.; Krummenacher, F.; de Oliveira, R.

    2006-10-01

    We report on a large area (15×15 mm2), high channel density (470 pixel/mm2), self-triggering CMOS analog chip that we have developed as a pixelized charge collecting electrode of a Micropattern Gas Detector. This device represents a big step forward both in terms of size and performance, and is in fact the last version of three generations of custom ASICs of increasing complexity. The top metal layer of the CMOS pixel array is patterned in a matrix of 105,600 hexagonal pixels with a 50 μm pitch. Each pixel is directly connected to the underlying full electronics chain which has been realized in the remaining five metal and single poly-silicon layers of a 0.18 μm VLSI technology. The chip, which has customizable self-triggering capabilities, also includes a signal pre-processing function for the automatic localization of the event coordinates. Thanks to these advances it is possible to significantly reduce the read-out time and the data volume by limiting the signal output only to those pixels belonging to the region of interest. In addition to the reduced read-out time and data volume, the very small pixel area and the use of a deep sub-micron CMOS technology has allowed bringing the noise down to 50 electrons ENC. Results from in depth tests of this device when coupled to a fine pitch (50 μm on a triangular pattern) Gas Electron Multiplier are presented. It was found that matching the read-out and gas amplification pitch allows getting optimal results. The experimental detector response to polarized and unpolarized X-ray radiation when working with two gas mixtures and two different photon energies is shown and the application of this detector for Astronomical X-ray Polarimetry is discussed. Results from a full Monte-Carlo simulation for several galactic and extragalactic astronomical sources are also reported.

  12. Prototype Active Silicon Sensor in 150 nm HR-CMOS technology for ATLAS Inner Detector Upgrade

    NASA Astrophysics Data System (ADS)

    Rymaszewski, P.; Barbero, M.; Breugnon, P.; Godiot, S.; Gonella, L.; Hemperek, T.; Hirono, T.; Hügging, F.; Krüger, H.; Liu, J.; Pangaud, P.; Peric, I.; Rozanov, A.; Wang, A.; Wermes, N.

    2016-02-01

    The LHC Phase-II upgrade will lead to a significant increase in luminosity, which in turn will bring new challenges for the operation of inner tracking detectors. A possible solution is to use active silicon sensors, taking advantage of commercial CMOS technologies. Currently ATLAS R&D programme is qualifying a few commercial technologies in terms of suitability for this task. In this paper a prototype designed in one of them (LFoundry 150 nm process) will be discussed. The chip architecture will be described, including different pixel types incorporated into the design, followed by simulation and measurement results.

  13. Iterative current mode per pixel ADC for 3D SoftChip implementation in CMOS

    NASA Astrophysics Data System (ADS)

    Lachowicz, Stefan W.; Rassau, Alexander; Lee, Seung-Minh; Eshraghian, Kamran; Lee, Mike M.

    2003-04-01

    Mobile multimedia communication has rapidly become a significant area of research and development constantly challenging boundaries on a variety of technological fronts. The processing requirements for the capture, conversion, compression, decompression, enhancement, display, etc. of increasingly higher quality multimedia content places heavy demands even on current ULSI (ultra large scale integration) systems, particularly for mobile applications where area and power are primary considerations. The ADC presented in this paper is designed for a vertically integrated (3D) system comprising two distinct layers bonded together using Indium bump technology. The top layer is a CMOS imaging array containing analogue-to-digital converters, and a buffer memory. The bottom layer takes the form of a configurable array processor (CAP), a highly parallel array of soft programmable processors capable of carrying out complex processing tasks directly on data stored in the top plane. This paper presents a ADC scheme for the image capture plane. The analogue photocurrent or sampled voltage is transferred to the ADC via a column or a column/row bus. In the proposed system, an array of analogue-to-digital converters is distributed, so that a one-bit cell is associated with one sensor. The analogue-to-digital converters are algorithmic current-mode converters. Eight such cells are cascaded to form an 8-bit converter. Additionally, each photo-sensor is equipped with a current memory cell, and multiple conversions are performed with scaled values of the photocurrent for colour processing.

  14. Active pixel image sensor with a winner-take-all mode of operation

    NASA Technical Reports Server (NTRS)

    Yadid-Pecht, Orly (Inventor); Fossum, Eric R. (Inventor); Mead, Carver (Inventor)

    2003-01-01

    An integrated CMOS semiconductor imaging device having two modes of operation that can be performed simultaneously to produce an output image and provide information of a brightest or darkest pixel in the image.

  15. A Pixel Readout Chip in 40 nm CMOS Process for High Count Rate Imaging Systems with Minimization of Charge Sharing Effects

    SciTech Connect

    Maj, Piotr; Grybos, P.; Szczgiel, R.; Kmon, P.; Drozd, A.; Deptuch, G.

    2013-11-07

    We present a prototype chip in 40 nm CMOS technology for readout of hybrid pixel detector. The prototype chip has a matrix of 18x24 pixels with a pixel pitch of 100 m. It can operate both in single photon counting (SPC) mode and in C8P1 mode. In SPC the measured ENC is 84 e rms (for the peaking time of 48 ns), while the effective offset spread is below 2 mV rms. In the C8P1 mode the chip reconstructs full charge deposited in the detector, even in the case of charge sharing, and it identifies a pixel with the largest charge deposition. The chip architecture and preliminary measurements are reported.

  16. A 10 MS/s 8-bit charge-redistribution ADC for hybrid pixel applications in 65 m CMOS

    NASA Astrophysics Data System (ADS)

    Kishishita, Tetsuichi; Hemperek, Tomasz; Krüger, Hans; Koch, Manuel; Germic, Leonard; Wermes, Norbert

    2013-12-01

    The design and measurement results of an 8-bit SAR ADC, based on a charge-redistribution DAC, are presented. This ADC is characterized by superior power efficiency and small area, realized by employing a lateral metal-metal capacitor array and a dynamic two-stage comparator. To avoid the need for a high-speed clock and its associated power consumption, an asynchronous logic was implemented in a logic control cell. A test chip has been developed in a 65 nm CMOS technology, including eight ADC channels with different layout flavors of the capacitor array, a transimpedance amplifier as a signal input structure, a serializer, and a custom-made LVDS driver for data transmission. The integral (INL) and differential (DNL) nonlinearities are measured below 0.5 LSB and 0.8 LSB, respectively, for the best channel operating at a sampling frequency of 10 MS/s. The area occupies 40 μm×70 μm for one ADC channel. The power consumption is estimated as 4 μW at 1 MS/s and 38 μW at 10 MS/s with a supply rail of 1.2 V. These excellent performance features and the natural radiation hardness of the design, due to the thin gate oxide thickness of transistors, are very interesting for front-end electronics ICs of future hybrid-pixel detector systems.

  17. Pixel pitch and particle energy influence on the dark current distribution of neutron irradiated CMOS image sensors.

    PubMed

    Belloir, Jean-Marc; Goiffon, Vincent; Virmontois, Cédric; Raine, Mélanie; Paillet, Philippe; Duhamel, Olivier; Gaillardin, Marc; Molina, Romain; Magnan, Pierre; Gilard, Olivier

    2016-02-22

    The dark current produced by neutron irradiation in CMOS Image Sensors (CIS) is investigated. Several CIS with different photodiode types and pixel pitches are irradiated with various neutron energies and fluences to study the influence of each of these optical detector and irradiation parameters on the dark current distribution. An empirical model is tested on the experimental data and validated on all the irradiated optical imagers. This model is able to describe all the presented dark current distributions with no parameter variation for neutron energies of 14 MeV or higher, regardless of the optical detector and irradiation characteristics. For energies below 1 MeV, it is shown that a single parameter has to be adjusted because of the lower mean damage energy per nuclear interaction. This model and these conclusions can be transposed to any silicon based solid-state optical imagers such as CIS or Charged Coupled Devices (CCD). This work can also be used when designing an optical imager instrument, to anticipate the dark current increase or to choose a mitigation technique. PMID:26907077

  18. Development of a radiation-hardened SRAM with EDAC algorithm for fast readout CMOS pixel sensors for charged particle tracking

    NASA Astrophysics Data System (ADS)

    Wei, X.; Li, B.; Chen, N.; Wang, J.; Zheng, R.; Gao, W.; Wei, T.; Gao, D.; Hu, Y.

    2014-08-01

    CMOS pixel sensors (CPS) are attractive for use in the innermost particle detectors for charged particle tracking due to their good trade-off between spatial resolution, material budget, radiation hardness, and readout speed. With the requirements of high readout speed and high radiation hardness to total ionizing dose (TID) for particle tracking, fast readout CPS are composed by integrating a data compression block and two SRAM IP cores. However, the radiation hardness of the SRAM IP cores is not as high as that of the other parts in CPS, and thus the radiation hardness of the whole CPS chip is lowered. Especially, when CPS are migrated into 0.18-μm processes, the single event upset (SEU) effects should be also considered besides TID and single event latchup (SEL) effects. This paper presents a radiation-hardened SRAM with enhanced radiation hardness to SEU. An error detection and correction (EDAC) algorithm and a bit-interleaving storage strategy are adopted in the design. The prototype design has been fabricated in a 0.18-μm process. The area of the new SRAM is increased 1.6 times as compared with a non-radiation-hardened SRAM due to the integration of EDAC algorithm and the adoption of radiation hardened layout. The access time is increased from 5 ns to 8 ns due to the integration of EDAC algorithm. The test results indicate that the design satisfy requirements of CPS for charged particle tracking.

  19. Full well capacity and quantum efficiency optimization for small size backside illuminated CMOS image pixels with a new photodiode structure

    NASA Astrophysics Data System (ADS)

    Yu, Sun; Ping, Zhang; Jiangtao, Xu; Zhiyuan, Gao; Chao, Xu

    2012-12-01

    To improve the full well capacity (FWC) of a small size backside illuminated (BSI) CMOS image sensor (CIS), the effect of photodiode capacitance (CPD) on FWC is studied, and a reformed pinned photodiode (PPD) structure is proposed. Two procedures are implemented for the optimization. The first is to form a varying doping concentration and depth stretched new N region, which is implemented by an additional higher-energy and lower-dose N type implant beneath the original N region. The FWC of this structure is increased by extending the side wall junctions in the substrate. Secondly, in order to help the enlarged well capacity achieve full depletion, two step P-type implants with different implant energies are introduced to form a P-type insertion region in the interior of the stretched N region. This vertical inserted P region guarantees that the proposed new PD structure achieves full depletion in the reset period. The simulation results show that the FWC can be improved from 1289e- to 6390e-, and this improvement does not sacrifice any image lag performance. Additionally, quantum efficiency (QE) is enhanced in the full wavelength range, especially 6.3% at 520 nm wavelength. This technique can not only be used in such BSI structures, but also adopted in an FSI pixel with any photodiode-type readout scheme.

  20. Backside-illuminated, high-QE, 3e- RoN, fast 700fps, 1760x1680 pixels CMOS imager for AO with highly parallel readout

    NASA Astrophysics Data System (ADS)

    Downing, Mark; Kolb, Johann; Baade, Dietrich; Balard, Philippe; Dierickx, Bart; Defernez, Arnaud; Dupont, Benoit; Feautrier, Philippe; Finger, Gert; Fryer, Martin; Gach, Jean-Luc; Guillaume, Christian; Hubin, Norbert; Iwert, Olaf; Jerram, Paul; Jorden, Paul; Pike, Andrew; Pratlong, Jerome; Reyes, Javier; Stadler, Eric; Walker, Andrew

    2012-07-01

    The success of the next generation of instruments for 8 to 40-m class telescopes will depend upon improving the image quality (correcting the distortion caused by atmospheric turbulence) by exploiting sophisticated Adaptive Optics (AO) systems. One of the critical components of the AO systems for the E-ELT has been identified as the Laser/Natural Guide Star (LGS/NGS) WaveFront Sensing (WFS) detector. The combination of large format, 1760x1680 pixels to finely sample (84x84 sub-apertures) the wavefront and the spot elongation of laser guide stars, fast frame rate of 700 (up to 1000) frames per second, low read noise (< 3e-), and high QE (> 90%) makes the development of such a device extremely challenging. Design studies by industry concluded that a thinned and backside-illuminated CMOS Imager as the most promising technology. This paper describes the multi-phased development plan that will ensure devices are available on-time for E-ELT first-light AO systems; the different CMOS pixel architectures studied; measured results of technology demonstrators that have validated the CMOS Imager approach; the design explaining the approach of massive parallelism (70,000 ADCs) needed to achieve low noise at high pixel rates of ~3 Gpixel/s ; the 88 channel LVDS data interface; the restriction that stitching (required due to the 5x6cm size) posed on the design and the solutions found to overcome these limitations. Two generations of the CMOS Imager will be built: a pioneering quarter sized device of 880x840 pixels capable of meeting first light needs of the E-ELT called NGSD (Natural Guide Star Detector); followed by the full size device, the LGSD (Laser Guide Star Detector). Funding sources: OPTICON FP6 and FP7 from European Commission and ESO.

  1. CMOS foveal image sensor chip

    NASA Technical Reports Server (NTRS)

    Bandera, Cesar (Inventor); Scott, Peter (Inventor); Sridhar, Ramalingam (Inventor); Xia, Shu (Inventor)

    2002-01-01

    A foveal image sensor integrated circuit comprising a plurality of CMOS active pixel sensors arranged both within and about a central fovea region of the chip. The pixels in the central fovea region have a smaller size than the pixels arranged in peripheral rings about the central region. A new photocharge normalization scheme and associated circuitry normalizes the output signals from the different size pixels in the array. The pixels are assembled into a multi-resolution rectilinear foveal image sensor chip using a novel access scheme to reduce the number of analog RAM cells needed. Localized spatial resolution declines monotonically with offset from the imager's optical axis, analogous to biological foveal vision.

  2. Active Pixel Sensors for electron microscopy

    NASA Astrophysics Data System (ADS)

    Denes, P.; Bussat, J.-M.; Lee, Z.; Radmillovic, V.

    2007-09-01

    The technology used for monolithic CMOS imagers, popular for cell phone cameras and other photographic applications, has been explored for charged particle tracking by the high-energy physics community for several years. This technology also lends itself to certain imaging detector applications in electron microscopy. We have been developing such detectors for several years at Lawrence Berkeley National Laboratory, and we and others have shown that this technology can offer excellent point-spread function, direct detection and high readout speed. In this paper, we describe some of the design constraints peculiar to electron microscopy and summarize where such detectors could play a useful role.

  3. Detection systems for mass spectrometry imaging: a perspective on novel developments with a focus on active pixel detectors.

    PubMed

    Jungmann, Julia H; Heeren, Ron M A

    2013-01-15

    Instrumental developments for imaging and individual particle detection for biomolecular mass spectrometry (imaging) and fundamental atomic and molecular physics studies are reviewed. Ion-counting detectors, array detection systems and high mass detectors for mass spectrometry (imaging) are treated. State-of-the-art detection systems for multi-dimensional ion, electron and photon detection are highlighted. Their application and performance in three different imaging modes--integrated, selected and spectral image detection--are described. Electro-optical and microchannel-plate-based systems are contrasted. The analytical capabilities of solid-state pixel detectors--both charge coupled device (CCD) and complementary metal oxide semiconductor (CMOS) chips--are introduced. The Medipix/Timepix detector family is described as an example of a CMOS hybrid active pixel sensor. Alternative imaging methods for particle detection and their potential for future applications are investigated. PMID:23239313

  4. Large area CMOS image sensors

    NASA Astrophysics Data System (ADS)

    Turchetta, R.; Guerrini, N.; Sedgwick, I.

    2011-01-01

    CMOS image sensors, also known as CMOS Active Pixel Sensors (APS) or Monolithic Active Pixel Sensors (MAPS), are today the dominant imaging devices. They are omnipresent in our daily life, as image sensors in cellular phones, web cams, digital cameras, ... In these applications, the pixels can be very small, in the micron range, and the sensors themselves tend to be limited in size. However, many scientific applications, like particle or X-ray detection, require large format, often with large pixels, as well as other specific performance, like low noise, radiation hardness or very fast readout. The sensors are also required to be sensitive to a broad spectrum of radiation: photons from the silicon cut-off in the IR down to UV and X- and gamma-rays through the visible spectrum as well as charged particles. This requirement calls for modifications to the substrate to be introduced to provide optimized sensitivity. This paper will review existing CMOS image sensors, whose size can be as large as a single CMOS wafer, and analyse the technical requirements and specific challenges of large format CMOS image sensors.

  5. Active pixel sensor array with multiresolution readout

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R. (Inventor); Kemeny, Sabrina E. (Inventor); Pain, Bedabrata (Inventor)

    1999-01-01

    An imaging device formed as a monolithic complementary metal oxide semiconductor integrated circuit in an industry standard complementary metal oxide semiconductor process, the integrated circuit including a focal plane array of pixel cells, each one of the cells including a photogate overlying the substrate for accumulating photo-generated charge in an underlying portion of the substrate and a charge coupled device section formed on the substrate adjacent the photogate having a sensing node and at least one charge coupled device stage for transferring charge from the underlying portion of the substrate to the sensing node. There is also a readout circuit, part of which can be disposed at the bottom of each column of cells and be common to all the cells in the column. The imaging device can also include an electronic shutter formed on the substrate adjacent the photogate, and/or a storage section to allow for simultaneous integration. In addition, the imaging device can include a multiresolution imaging circuit to provide images of varying resolution. The multiresolution circuit could also be employed in an array where the photosensitive portion of each pixel cell is a photodiode. This latter embodiment could further be modified to facilitate low light imaging.

  6. Time-resolved Förster-resonance-energy-transfer DNA assay on an active CMOS microarray

    PubMed Central

    Schwartz, David Eric; Gong, Ping; Shepard, Kenneth L.

    2008-01-01

    We present an active oligonucleotide microarray platform for time-resolved Förster resonance energy transfer (TR-FRET) assays. In these assays, immobilized probe is labeled with a donor fluorophore and analyte target is labeled with a fluorescence quencher. Changes in the fluorescence decay lifetime of the donor are measured to determine the extent of hybridization. In this work, we demonstrate that TR-FRET assays have reduced sensitivity to variances in probe surface density compared with standard fluorescence-based microarray assays. Use of an active array substrate, fabricated in a standard complementary metal-oxide-semiconductor (CMOS) process, provides the additional benefits of reduced system complexity and cost. The array consists of 4096 independent single-photon avalanche diode (SPAD) pixel sites and features on-chip time-to-digital conversion. We demonstrate the functionality of our system by measuring a DNA target concentration series using TR-FRET with semiconductor quantum dot donors. PMID:18515059

  7. Active-Pixel Image Sensors With Programmable Resolution

    NASA Technical Reports Server (NTRS)

    Kemeny, Sabrina E.; Fossum, Eric R.; Pain, Bedabrata; Nakamura, Junichi; Matthies, Larry H.

    1996-01-01

    Active-pixel image sensors with programmable resolution proposed for use in applications in which speed and efficiency of processing of image data enhanced by providing those data at varying resolutions. Such applications include modeling of biological vision, stereoscopic range-finding, recognition of patterns, tracking targets, and progressive transmission of compressed images. In target-tracking application, sensor initially forms low-resolution image from which area of interest identified, then sensor set at high resolution for examination of identified area. Outputs of contiguous pixels combined. Sensor of this type made to act as though it comprised fewer and larger pixels.

  8. Low-Voltage 96 dB Snapshot CMOS Image Sensor with 4.5 nW Power Dissipation per Pixel

    PubMed Central

    Spivak, Arthur; Teman, Adam; Belenky, Alexander; Yadid-Pecht, Orly; Fish, Alexander

    2012-01-01

    Modern “smart” CMOS sensors have penetrated into various applications, such as surveillance systems, bio-medical applications, digital cameras, cellular phones and many others. Reducing the power of these sensors continuously challenges designers. In this paper, a low power global shutter CMOS image sensor with Wide Dynamic Range (WDR) ability is presented. This sensor features several power reduction techniques, including a dual voltage supply, a selective power down, transistors with different threshold voltages, a non-rationed logic, and a low voltage static memory. A combination of all these approaches has enabled the design of the low voltage “smart” image sensor, which is capable of reaching a remarkable dynamic range, while consuming very low power. The proposed power-saving solutions have allowed the maintenance of the standard architecture of the sensor, reducing both the time and the cost of the design. In order to maintain the image quality, a relation between the sensor performance and power has been analyzed and a mathematical model, describing the sensor Signal to Noise Ratio (SNR) and Dynamic Range (DR) as a function of the power supplies, is proposed. The described sensor was implemented in a 0.18 um CMOS process and successfully tested in the laboratory. An SNR of 48 dB and DR of 96 dB were achieved with a power dissipation of 4.5 nW per pixel. PMID:23112588

  9. Low-voltage 96 dB snapshot CMOS image sensor with 4.5 nW power dissipation per pixel.

    PubMed

    Spivak, Arthur; Teman, Adam; Belenky, Alexander; Yadid-Pecht, Orly; Fish, Alexander

    2012-01-01

    Modern "smart" CMOS sensors have penetrated into various applications, such as surveillance systems, bio-medical applications, digital cameras, cellular phones and many others. Reducing the power of these sensors continuously challenges designers. In this paper, a low power global shutter CMOS image sensor with Wide Dynamic Range (WDR) ability is presented. This sensor features several power reduction techniques, including a dual voltage supply, a selective power down, transistors with different threshold voltages, a non-rationed logic, and a low voltage static memory. A combination of all these approaches has enabled the design of the low voltage "smart" image sensor, which is capable of reaching a remarkable dynamic range, while consuming very low power. The proposed power-saving solutions have allowed the maintenance of the standard architecture of the sensor, reducing both the time and the cost of the design. In order to maintain the image quality, a relation between the sensor performance and power has been analyzed and a mathematical model, describing the sensor Signal to Noise Ratio (SNR) and Dynamic Range (DR) as a function of the power supplies, is proposed. The described sensor was implemented in a 0.18 um CMOS process and successfully tested in the laboratory. An SNR of 48 dB and DR of 96 dB were achieved with a power dissipation of 4.5 nW per pixel. PMID:23112588

  10. Charged particle detection performances of CMOS pixel sensors produced in a 0.18 μm process with a high resistivity epitaxial layer

    NASA Astrophysics Data System (ADS)

    Senyukov, S.; Baudot, J.; Besson, A.; Claus, G.; Cousin, L.; Dorokhov, A.; Dulinski, W.; Goffe, M.; Hu-Guo, C.; Winter, M.

    2013-12-01

    The apparatus of the ALICE experiment at CERN will be upgraded in 2017/18 during the second long shutdown of the LHC (LS2). A major motivation for this upgrade is to extend the physics reach for charmed and beauty particles down to low transverse momenta. This requires a substantial improvement of the spatial resolution and the data rate capability of the ALICE Inner Tracking System (ITS). To achieve this goal, the new ITS will be equipped with 50 μm thin CMOS Pixel Sensors (CPS) covering either the three innermost layers or all the 7 layers of the detector. The CPS being developed for the ITS upgrade at IPHC (Strasbourg) is derived from the MIMOSA 28 sensor realised for the STAR-PXL at RHIC in a 0.35 μm CMOS process. In order to satisfy the ITS upgrade requirements in terms of readout speed and radiation tolerance, a CMOS process with a reduced feature size and a high resistivity epitaxial layer should be exploited. In this respect, the charged particle detection performance and radiation hardness of the TowerJazz 0.18 μm CMOS process were studied with the help of the first prototype chip MIMOSA 32. The beam tests performed with negative pions of 120 GeV/c at the CERN-SPS allowed to measure a signal-to-noise ratio (SNR) for the non-irradiated chip in the range between 22 and 32 depending on the pixel design. The chip irradiated with the combined dose of 1 MRad and 1013neq /cm2 was observed to yield an SNR ranging between 11 and 23 for coolant temperatures varying from 15 °C to 30 °C. These SNR values were measured to result in particle detection efficiencies above 99.5% and 98% before and after irradiation, respectively. These satisfactory results allow to validate the TowerJazz 0.18 μm CMOS process for the ALICE ITS upgrade.

  11. CMOS Image Sensors: Electronic Camera On A Chip

    NASA Technical Reports Server (NTRS)

    Fossum, E. R.

    1995-01-01

    Recent advancements in CMOS image sensor technology are reviewed, including both passive pixel sensors and active pixel sensors. On- chip analog to digital converters and on-chip timing and control circuits permit realization of an electronic camera-on-a-chip. Highly miniaturized imaging systems based on CMOS image sensor technology are emerging as a competitor to charge-coupled devices for low cost uses.

  12. Low-power priority Address-Encoder and Reset-Decoder data-driven readout for Monolithic Active Pixel Sensors for tracker system

    NASA Astrophysics Data System (ADS)

    Yang, P.; Aglieri, G.; Cavicchioli, C.; Chalmet, P. L.; Chanlek, N.; Collu, A.; Gao, C.; Hillemanns, H.; Junique, A.; Kofarago, M.; Keil, M.; Kugathasan, T.; Kim, D.; Kim, J.; Lattuca, A.; Marin Tobon, C. A.; Marras, D.; Mager, M.; Martinengo, P.; Mazza, G.; Mugnier, H.; Musa, L.; Puggioni, C.; Rousset, J.; Reidt, F.; Riedler, P.; Snoeys, W.; Siddhanta, S.; Usai, G.; van Hoorne, J. W.; Yi, J.

    2015-06-01

    Active Pixel Sensors used in High Energy Particle Physics require low power consumption to reduce the detector material budget, low integration time to reduce the possibilities of pile-up and fast readout to improve the detector data capability. To satisfy these requirements, a novel Address-Encoder and Reset-Decoder (AERD) asynchronous circuit for a fast readout of a pixel matrix has been developed. The AERD data-driven readout architecture operates the address encoding and reset decoding based on an arbitration tree, and allows us to readout only the hit pixels. Compared to the traditional readout structure of the rolling shutter scheme in Monolithic Active Pixel Sensors (MAPS), AERD can achieve a low readout time and a low power consumption especially for low hit occupancies. The readout is controlled at the chip periphery with a signal synchronous with the clock, allows a good digital and analogue signal separation in the matrix and a reduction of the power consumption. The AERD circuit has been implemented in the TowerJazz 180 nm CMOS Imaging Sensor (CIS) process with full complementary CMOS logic in the pixel. It works at 10 MHz with a matrix height of 15 mm. The energy consumed to read out one pixel is around 72 pJ. A scheme to boost the readout speed to 40 MHz is also discussed. The sensor chip equipped with AERD has been produced and characterised. Test results including electrical beam measurement are presented.

  13. Towards a 10 μs, thin and high resolution pixelated CMOS sensor system for future vertex detectors

    NASA Astrophysics Data System (ADS)

    De Masi, R.; Amar-Youcef, S.; Baudot, J.; Bertolone, G.; Brogna, A.; Chon-Sen, N.; Claus, G.; Colledani, C.; Degerli, Y.; Deveaux, M.; Dorokhov, A.; Doziére, G.; Dulinski, W.; Gelin, M.; Goffe, M.; Fontaine, J. C.; Hu-Guo, Ch.; Himmi, A.; Jaaskelainen, K.; Koziel, M.; Morel, F.; Müntz, C.; Orsini, F.; Santos, C.; Schrader, C.; Specht, M.; Stroth, J.; Valin, I.; Voutsinas, G.; Wagner, F. M.; Winter, M.

    2011-02-01

    The physics goals of many high energy experiments require a precise determination of decay vertices, imposing severe constraints on vertex detectors (readout speed, granularity, material budget,…). The IPHC-IRFU collaboration developed a sensor architecture to comply with these requirements. The first full scale CMOS sensor was realised and equips the reference planes of the EUDET beam telescope. Its architecture is being adapted to the needs of the STAR (RHIC) and CBM (FAIR) experiments. It is a promising candidate for the ILC experiments and the ALICE detector upgrade (LHC). A substantial improvement to the CMOS sensor performances, especially in terms of radiation hardness, should come from a new fabrication technology with depleted sensitive volume. A prototype sensor was fabricated to explore the benefits of the technology. The crucial system integration issue is also currently being addressed. In 2009 the PLUME collaboration was set up to investigate the feasibility and performances of a light double sided ladder equipped with CMOS sensors, aimed primarily for the ILC vertex detector but also of interest for other applications such as the CBM vertex detector.

  14. Studies for a 10 μs, thin, high resolution CMOS pixel sensor for future vertex detectors

    NASA Astrophysics Data System (ADS)

    Voutsinas, G.; Amar-Youcef, S.; Baudot, J.; Bertolone, G.; Brogna, A.; Chon-Sen, N.; Claus, G.; Colledani, C.; Dorokhov, A.; Dozière, G.; Dulinski, W.; Degerli, Y.; De Masi, R.; Deveaux, M.; Gelin, M.; Goffe, M.; Hu-Guo, Ch.; Himmi, A.; Jaaskelainen, K.; Koziel, M.; Morel, F.; Müntz, C.; Orsini, F.; Santos, C.; Schrader, C.; Specht, M.; Stroth, J.; Valin, I.; Wagner, F. M.; Winter, M.

    2011-06-01

    Future high energy physics (HEP) experiments require detectors with unprecedented performances for track and vertex reconstruction. These requirements call for high precision sensors, with low material budget and short integration time. The development of CMOS sensors for HEP applications was initiated at IPHC Strasbourg more than 10 years ago, motivated by the needs for vertex detectors at the International Linear Collider (ILC) [R. Turchetta et al, NIM A 458 (2001) 677]. Since then several other applications emerged. The first real scale digital CMOS sensor MIMOSA26 equips Flavour Tracker at RHIC, as well as for the microvertex detector of the CBM experiment at FAIR. MIMOSA sensors may also offer attractive performances for the ALICE upgrade at LHC. This paper will demonstrate the substantial performance improvement of CMOS sensors based on a high resistivity epitaxial layer. First studies for integrating the sensors into a detector system will be addressed and finally the way to go to a 10 μs readout sensor will be discussed.

  15. Low area 4-bit 5 MS/s flash-type digitizer for hybrid-pixel detectors - Design study in 180 nm and 40 nm CMOS

    NASA Astrophysics Data System (ADS)

    Otfinowski, Piotr; Grybos, Pawel

    2015-11-01

    We report on the design of a 4-bit flash ADC with dynamic offset correction dedicated to measurement systems based on a pixel architecture. The presented converter was manufactured in two CMOS technologies: widespread and economical 180 nm and modern 40 nm process. The designs are optimized for the lowest area occupancy resulting in chip areas of 160×55 μm2 and 35×25 μm2. The experimental results indicate integral nonlinearity of +0.35/-0.21 LSB and +0.28/-0.25 LSB and power consumption of 52 μW and 17 μW at 5 MS/s for the prototypes in 180 nm and 40 nm technologies respectively.

  16. High-voltage CMOS detectors

    NASA Astrophysics Data System (ADS)

    Ehrler, F.; Blanco, R.; Leys, R.; Perić, I.

    2016-07-01

    High-voltage CMOS (HVCMOS) pixel sensors are depleted active pixel sensors implemented in standard commercial CMOS processes. The sensor element is the n-well/p-substrate diode. The sensor electronics are entirely placed inside the n-well which is at the same time used as the charge collection electrode. High voltage is used to deplete the part of the substrate around the n-well. HVCMOS sensors allow implementation of complex in-pixel electronics. This, together with fast signal collection, allows a good time resolution, which is required for particle tracking in high energy physics. HVCMOS sensors will be used in Mu3e experiment at PSI and are considered as an option for both ATLAS and CLIC (CERN). Radiation tolerance and time walk compensation have been tested and results are presented.

  17. Charge collection properties of a depleted monolithic active pixel sensor using a HV-SOI process

    NASA Astrophysics Data System (ADS)

    Fernandez-Perez, S.; Backhaus, M.; Fernandez-Garcia, M.; Gallrapp, C.; Hemperek, T.; Kishishita, T.; Krueger, H.; Moll, M.; Padilla, C.; Pernegger, H.

    2016-01-01

    New pixel detector concepts, based on commercial high voltage and/or high resistivity CMOS processes, are being investigated as a possible candidate to the inner and outer layers of the ATLAS Inner Tracker in the HL-LHC upgrade. A depleted monolithic active pixel sensor on thick film SOI technology is being extensively investigated for that purpose. This particular technology provides a double well structure, which shields the thin gate oxide transistors from the Buried Oxide (BOX). In addition, the distance between transistors and BOX is one order of magnitude bigger than conventional SOI technologies, making the technology promising against its main limitations, as radiation hardness or back gate effects. Its radiation hardness to Total Ionizing Dose (TID) and the absence of back gate effect up to 700 Mrad has been measured and published [1]. The process allows the use of high voltages (up to 300V) which are used to partially deplete the substrate. The process allows fabrication in higher resistivity, therefore a fully depleted substrate could be achieved after thinning. This article shows the results on charge collection properties of the silicon bulk below the BOX by different techniques, in a laboratory with radioactive sources and by edge Transient Current Technique, for unirradiated and irradiated samples.

  18. Hybrid Pixel Detectors for gamma/X-ray imaging

    NASA Astrophysics Data System (ADS)

    Hatzistratis, D.; Theodoratos, G.; Zografos, V.; Kazas, I.; Loukas, D.; Lambropoulos, C. P.

    2015-09-01

    Hybrid pixel detectors are made by direct converting high-Z semi-insulating single crystalline material coupled to complementary-metal-oxide semiconductor (CMOS) readout electronics. They are attractive because direct conversion exterminates all the problems of spatial localization related to light diffusion, energy resolution, is far superior from the combination of scintillation crystals and photomultipliers and lithography can be used to pattern electrodes with very fine pitch. We are developing 2-D pixel CMOS ASICs, connect them to pixilated CdTe crystals with the flip chip and bump bonding method and characterize the hybrids. We have designed a series of circuits, whose latest member consists of a 50×25 pixel array with 400um pitch and an embedded controller. In every pixel a full spectroscopic channel with time tagging information has been implemented. The detectors are targeting Compton scatter imaging and they can be used for coded aperture imaging too. Hybridization using CMOS can overcome the limit put on pixel circuit complexity by the use of thin film transistors (TFT) in large flat panels. Hybrid active pixel sensors are used in dental imaging and other applications (e.g. industrial CT etc.). Thus X-ray imaging can benefit from the work done on dynamic range enhancement methods developed initially for visible and infrared CMOS pixel sensors. A 2-D CMOS ASIC with 100um pixel pitch to demonstrate the feasibility of such methods in the context of X-ray imaging has been designed.

  19. Low-noise low-jitter 32-pixels CMOS single-photon avalanche diodes array for single-photon counting from 300 nm to 900 nm.

    PubMed

    Scarcella, Carmelo; Tosi, Alberto; Villa, Federica; Tisa, Simone; Zappa, Franco

    2013-12-01

    We developed a single-photon counting multichannel detection system, based on a monolithic linear array of 32 CMOS SPADs (Complementary Metal-Oxide-Semiconductor Single-Photon Avalanche Diodes). All channels achieve a timing resolution of 100 ps (full-width at half maximum) and a photon detection efficiency of 50% at 400 nm. Dark count rate is very low even at room temperature, being about 125 counts/s for 50 μm active area diameter SPADs. Detection performance and microelectronic compactness of this CMOS SPAD array make it the best candidate for ultra-compact time-resolved spectrometers with single-photon sensitivity from 300 nm to 900 nm. PMID:24387425

  20. Low-noise low-jitter 32-pixels CMOS single-photon avalanche diodes array for single-photon counting from 300 nm to 900 nm

    SciTech Connect

    Scarcella, Carmelo; Tosi, Alberto Villa, Federica; Tisa, Simone; Zappa, Franco

    2013-12-15

    We developed a single-photon counting multichannel detection system, based on a monolithic linear array of 32 CMOS SPADs (Complementary Metal-Oxide-Semiconductor Single-Photon Avalanche Diodes). All channels achieve a timing resolution of 100 ps (full-width at half maximum) and a photon detection efficiency of 50% at 400 nm. Dark count rate is very low even at room temperature, being about 125 counts/s for 50 μm active area diameter SPADs. Detection performance and microelectronic compactness of this CMOS SPAD array make it the best candidate for ultra-compact time-resolved spectrometers with single-photon sensitivity from 300 nm to 900 nm.

  1. Pixel-One

    NASA Astrophysics Data System (ADS)

    Pedichini, F.; Di Paola, A.; Testa, V.

    2010-07-01

    The early future of astronomy will be dominated by Extremely Large Telescopes where the focal lengths will be of the order of several hundred meters. This yields focal plane sizes of roughly one square meter to obtain a field of view of about 5 x 5 arcmin. When operated in seeing limited mode this field is correctly sampled with 1x1mm pixels. Such a sampling can be achieved using a peculiar array of tiny CMOS active photodiodes illuminated through microlenses or lightpipes. If the photodiode is small enough and utilizes the actual pixel technology, its dark current can be kept well below the sky background photocurrent, thus avoiding the use of cumbersome cryogenics systems. An active smart electronics will manage each pixel up to the A/D conversion and data transfer. This modular block is the Pixel-One. A 30x30 mm tile filled with 1000 Pixel-Ones could be the basic unit to mosaic very large focal planes. By inserting dispersion elements inside the optical path of the lenslet array one could also produce a low dispersed spectrum of each focal plane sub-aperture and, by using an array of few smart photodiodes, also get multi-wavelength information in the optical band for each equivalent focal plane pixel. An application to the E-ELT is proposed.

  2. PIXIE III: a very large area photon-counting CMOS pixel ASIC for sharp X-ray spectral imaging

    NASA Astrophysics Data System (ADS)

    Bellazzini, R.; Brez, A.; Spandre, G.; Minuti, M.; Pinchera, M.; Delogu, P.; de Ruvo, P. L.; Vincenzi, A.

    2015-01-01

    PIXIE III is the third generation of very large area (32 × 25 mm2) pixel ASICs developed by Pixirad Imaging Counters s.r.l. to be used in combination with suitable X-ray sensor materials (Silicon, CdTe, GaAs) in hybrid assemblies using flip-chip bonding. A Pixirad unit module based on PIXIE III shows several advances compared to what has been available up to now. It has a very broad energy range (from 2 to 100 keV before full pulse saturation), high speed (100 ns peaking time), high frame rate (larger than 500 fps), dead-time-free operation, good energy resolution (around 2 keV at 20 keV), high photo-peak fraction and sharp spectral separation between the color images. In this paper the results obtained with PIXIE III both in a test bench set-up as well in X-ray imaging applications are discussed.

  3. Active pixel sensor pixel having a photodetector whose output is coupled to an output transistor gate

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R. (Inventor); Nakamura, Junichi (Inventor); Kemeny, Sabrina E. (Inventor)

    2005-01-01

    An imaging device formed as a monolithic complementary metal oxide semiconductor integrated circuit in an industry standard complementary metal oxide semiconductor process, the integrated circuit including a focal plane array of pixel cells, each one of the cells including a photogate overlying the substrate for accumulating photo-generated charge in an underlying portion of the substrate and a charge coupled device section formed on the substrate adjacent the photogate having a sensing node and at least one charge coupled device stage for transferring charge from the underlying portion of the substrate to the sensing node. There is also a readout circuit, part of which can be disposed at the bottom of each column of cells and be common to all the cells in the column. A Simple Floating Gate (SFG) pixel structure could also be employed in the imager to provide a non-destructive readout and smaller pixel sizes.

  4. Low-Power CMOS Laser Doppler Imaging Using Non-CDS Pixel Readout and 13.6-bit SAR ADC.

    PubMed

    Chen, Denis Guangyin; Law, Man-Kay; Lian, Yong; Bermak, Amine

    2016-02-01

    Laser Doppler imaging (LDI) measures particle flows such as blood perfusion by sensing their Doppler shift. This paper is the first of its kind in analyzing the effect of circuit noise on LDI precision which is distinctively different from conventional imaging. Based on this result, it presents a non-correlated-double-sampling (non-CDS) pixel readout scheme along with a high-resolution successive-approximation-register (SAR) analog-to-digital-converter (ADC) with 13.6b effective resolution (ER). Measurement results from the prototype chip in 0.18 μm technology confirm the theoretical analysis and show that the two techniques improve LDI sensing precision by 6.9 dB and 4.4 dB (compared to a 10b ADC) respectively without analog pre-amplification. The sensor's ADC occupies 518 μm×84 μm and is suitable for fast column parallel readout. Its differential non-linearity (DNL), integral non-linearity (INL), and input referred noise are +3.0/-2.8 LSB, +24/-17 LSB, and 110 μVrms respectively, leading to a Figure-of-Merit (FoM) of 23 fJ/state which makes it one of the most energy efficient image sensor ADCs and an order of magnitude better than the best reported LDI system using commercial high-speed image sensors. PMID:25532189

  5. A High-Speed, Event-Driven, Active Pixel Sensor Readout for Photon-Counting Microchannel Plate Detectors

    NASA Technical Reports Server (NTRS)

    Kimble, Randy A.; Pain, Bedabrata; Norton, Timothy J.; Haas, J. Patrick; Oegerle, William R. (Technical Monitor)

    2002-01-01

    Silicon array readouts for microchannel plate intensifiers offer several attractive features. In this class of detector, the electron cloud output of the MCP intensifier is converted to visible light by a phosphor; that light is then fiber-optically coupled to the silicon array. In photon-counting mode, the resulting light splashes on the silicon array are recognized and centroided to fractional pixel accuracy by off-chip electronics. This process can result in very high (MCP-limited) spatial resolution while operating at a modest MCP gain (desirable for dynamic range and long term stability). The principal limitation of intensified CCD systems of this type is their severely limited local dynamic range, as accurate photon counting is achieved only if there are not overlapping event splashes within the frame time of the device. This problem can be ameliorated somewhat by processing events only in pre-selected windows of interest of by using an addressable charge injection device (CID) for the readout array. We are currently pursuing the development of an intriguing alternative readout concept based on using an event-driven CMOS Active Pixel Sensor. APS technology permits the incorporation of discriminator circuitry within each pixel. When coupled with suitable CMOS logic outside the array area, the discriminator circuitry can be used to trigger the readout of small sub-array windows only when and where an event splash has been detected, completely eliminating the local dynamic range problem, while achieving a high global count rate capability and maintaining high spatial resolution. We elaborate on this concept and present our progress toward implementing an event-driven APS readout.

  6. A High-Speed, Event-Driven, Active Pixel Sensor Readout for Photon-Counting Microchannel Plate Detectors

    NASA Technical Reports Server (NTRS)

    Kimble, Randy A.; Pain, B.; Norton, T. J.; Haas, P.; Fisher, Richard R. (Technical Monitor)

    2001-01-01

    Silicon array readouts for microchannel plate intensifiers offer several attractive features. In this class of detector, the electron cloud output of the MCP intensifier is converted to visible light by a phosphor; that light is then fiber-optically coupled to the silicon array. In photon-counting mode, the resulting light splashes on the silicon array are recognized and centroided to fractional pixel accuracy by off-chip electronics. This process can result in very high (MCP-limited) spatial resolution for the readout while operating at a modest MCP gain (desirable for dynamic range and long term stability). The principal limitation of intensified CCD systems of this type is their severely limited local dynamic range, as accurate photon counting is achieved only if there are not overlapping event splashes within the frame time of the device. This problem can be ameliorated somewhat by processing events only in pre-selected windows of interest or by using an addressable charge injection device (CID) for the readout array. We are currently pursuing the development of an intriguing alternative readout concept based on using an event-driven CMOS Active Pixel Sensor. APS technology permits the incorporation of discriminator circuitry within each pixel. When coupled with suitable CMOS logic outside the array area, the discriminator circuitry can be used to trigger the readout of small sub-array windows only when and where an event splash has been detected, completely eliminating the local dynamic range problem, while achieving a high global count rate capability and maintaining high spatial resolution. We elaborate on this concept and present our progress toward implementing an event-driven APS readout.

  7. Results of the 2015 testbeam of a 180 nm AMS High-Voltage CMOS sensor prototype

    NASA Astrophysics Data System (ADS)

    Benoit, M.; Bilbao de Mendizabal, J.; Casse, G.; Chen, H.; Chen, K.; Di Bello, F. A.; Ferrere, D.; Golling, T.; Gonzalez-Sevilla, S.; Iacobucci, G.; Lanni, F.; Liu, H.; Meloni, F.; Meng, L.; Miucci, A.; Muenstermann, D.; Nessi, M.; Perić, I.; Rimoldi, M.; Ristic, B.; Barrero Pinto, M. Vicente; Vossebeld, J.; Weber, M.; Wu, W.; Xu, L.

    2016-07-01

    Active pixel sensors based on the High-Voltage CMOS technology are being investigated as a viable option for the future pixel tracker of the ATLAS experiment at the High-Luminosity LHC. This paper reports on the testbeam measurements performed at the H8 beamline of the CERN Super Proton Synchrotron on a High-Voltage CMOS sensor prototype produced in 180 nm AMS technology. Results in terms of tracking efficiency and timing performance, for different threshold and bias conditions, are shown.

  8. Monolithic Active Pixel Matrix with Binary Counters (MAMBO) ASIC

    SciTech Connect

    Khalid, Farah F.; Deptuch, Grzegorz; Shenai, Alpana; Yarema, Raymond J.; /Fermilab

    2010-11-01

    Monolithic Active Matrix with Binary Counters (MAMBO) is a counting ASIC designed for detecting and measuring low energy X-rays from 6-12 keV. Each pixel contains analogue functionality implemented with a charge preamplifier, CR-RC{sup 2} shaper and a baseline restorer. It also contains a window comparator which can be trimmed by 4 bit DACs to remove systematic offsets. The hits are registered by a 12 bit ripple counter which is reconfigured as a shift register to serially output the data from the entire ASIC. Each pixel can be tested individually. Two diverse approaches have been used to prevent coupling between the detector and electronics in MAMBO III and MAMBO IV. MAMBO III is a 3D ASIC, the bottom ASIC consists of diodes which are connected to the top ASIC using {mu}-bump bonds. The detector is decoupled from the electronics by physically separating them on two tiers and using several metal layers as a shield. MAMBO IV is a monolithic structure which uses a nested well approach to isolate the detector from the electronics. The ASICs are being fabricated using the SOI 0.2 {micro}m OKI process, MAMBO III is 3D bonded at T-Micro and MAMBO IV nested well structure was developed in collaboration between OKI and Fermilab.

  9. Monolithic active pixel matrix with binary counters (MAMBO III) ASIC

    SciTech Connect

    Khalid, Farah; Deptuch, Grzegorz; Shenai, Alpana; Yarema, Raymond; /Fermilab

    2010-01-01

    Monolithic Active Matrix with Binary Counters (MAMBO) is a counting ASIC designed for detecting and measuring low energy X-rays from 6-12keV. Each pixel contains analogue functionality implemented with a charge preamplifier, CR-RC{sup 2} shaper and a baseline restorer. It also contains a window comparator which can be trimmed by 4 bit DACs to remove systematic offsets. The hits are registered by a 12 bit ripple counter which is reconfigured as a shift register to serially output the data from the entire ASIC. Each pixel can be tested individually. Two diverse approaches have been used to prevent coupling between the detector and electronics in MAMBO III and MAMBO IV. MAMBO III is a 3D ASIC, the bottom ASIC consists of diodes which are connected to the top ASIC using {mu}-bump bonds. The detector is decoupled from the electronics by physically separating them on two tiers and using several metal layers as a shield. MAMBO IV is a monolithic structure which uses a nested well approach to isolate the detector from the electronics. The ASICs are being fabricated using the SOI 0.2 {micro}m OKI process, MAMBO III is 3D bonded at T-Micro and MAMBO IV nested well structure was developed in collaboration between OKI and Fermilab.

  10. Characterization study of an intensified complementary metal-oxide-semiconductor active pixel sensor

    NASA Astrophysics Data System (ADS)

    Griffiths, J. A.; Chen, D.; Turchetta, R.; Royle, G. J.

    2011-03-01

    An intensified CMOS active pixel sensor (APS) has been constructed for operation in low-light-level applications: a high-gain, fast-light decay image intensifier has been coupled via a fiber optic stud to a prototype "VANILLA" APS, developed by the UK based MI3 consortium. The sensor is capable of high frame rates and sparse readout. This paper presents a study of the performance parameters of the intensified VANILLA APS system over a range of image intensifier gain levels when uniformly illuminated with 520 nm green light. Mean-variance analysis shows the APS saturating around 3050 Digital Units (DU), with the maximum variance increasing with increasing image intensifier gain. The system's quantum efficiency varies in an exponential manner from 260 at an intensifier gain of 7.45 × 103 to 1.6 at a gain of 3.93 × 101. The usable dynamic range of the system is 60 dB for intensifier gains below 1.8 × 103, dropping to around 40 dB at high gains. The conclusion is that the system shows suitability for the desired application.

  11. First evidence of phase-contrast imaging with laboratory sources and active pixel sensors

    NASA Astrophysics Data System (ADS)

    Olivo, A.; Arvanitis, C. D.; Bohndiek, S. E.; Clark, A. T.; Prydderch, M.; Turchetta, R.; Speller, R. D.

    2007-11-01

    The aim of the present work is to achieve a first step towards combining the advantages of an innovative X-ray imaging technique—phase-contrast imaging (XPCi)—with those of a new class of sensors, i.e. CMOS-based active pixel sensors (APSs). The advantages of XPCi are well known and include increased image quality and detection of details invisible to conventional techniques, with potential application fields encompassing the medical, biological, industrial and security areas. Vanilla, one of the APSs developed by the MI-3 collaboration (see http://mi3.shef.ac.uk), was thoroughly characterised and an appropriate scintillator was selected to provide X-ray sensitivity. During this process, a set of phase-contrast images of different biological samples was acquired by means of the well-established free-space propagation XPCi technique. The obtained results are very encouraging and are in optimum agreement with the predictions of a simulation recently developed by some of the authors thus further supporting its reliability. This paper presents these preliminary results in detail and discusses in brief both the background to this work and its future developments.

  12. Evaluation of a single-pixel one-transistor active pixel sensor for fingerprint imaging

    NASA Astrophysics Data System (ADS)

    Xu, Man; Ou, Hai; Chen, Jun; Wang, Kai

    2015-08-01

    Since it first appeared in iPhone 5S in 2013, fingerprint identification (ID) has rapidly gained popularity among consumers. Current fingerprint-enabled smartphones unanimously consists of a discrete sensor to perform fingerprint ID. This architecture not only incurs higher material and manufacturing cost, but also provides only static identification and limited authentication. Hence as the demand for a thinner, lighter, and more secure handset grows, we propose a novel pixel architecture that is a photosensitive device embedded in a display pixel and detects the reflected light from the finger touch for high resolution, high fidelity and dynamic biometrics. To this purpose, an amorphous silicon (a-Si:H) dual-gate photo TFT working in both fingerprint-imaging mode and display-driving mode will be developed.

  13. Monolithic active pixel radiation detector with shielding techniques

    DOEpatents

    Deptuch, Grzegorz W.

    2016-09-06

    A monolithic active pixel radiation detector including a method of fabricating thereof. The disclosed radiation detector can include a substrate comprising a silicon layer upon which electronics are configured. A plurality of channels can be formed on the silicon layer, wherein the plurality of channels are connected to sources of signals located in a bulk part of the substrate, and wherein the signals flow through electrically conducting vias established in an isolation oxide on the substrate. One or more nested wells can be configured from the substrate, wherein the nested wells assist in collecting charge carriers released in interaction with radiation and wherein the nested wells further separate the electronics from the sensing portion of the detector substrate. The detector can also be configured according to a thick SOA method of fabrication.

  14. First use of a high-sensitivity active pixel sensor array as a detector for electron microscopy

    NASA Astrophysics Data System (ADS)

    Xuong, Nguyen-Huu; Milazzo, Anna-Clare; LeBlanc, Philippe; Duttweiler, Fred; Bouwer, James; Peltier, Steve; Ellisman, Mark; Denes, Peter; Bieser, Fred; Matis, Howard S.; Wieman, Howard; Kleinfelder, Stuart

    2004-06-01

    There is an urgent need to replace film and CCD cameras as recording instruments for transmission electron microscopy (TEM). Film is too cumbersome to process and CCD cameras have low resolution, marginal to poor signal-to-noise ratio for single electron detection and high spatial distortion. To find a replacement device, we have tested a high sensitivity active pixel sensor (APS) array currently being developed for nuclear physics. The tests were done at 120 keV in a JEOL 1200 electron microscope. At this energy, each electron produced on average a signal-tonoise ratio about 20/1. The spatial resolution was also excellent with the full width at half maximum (FWHM) about 20 microns. Since it is very radiation tolerant and has almost no spatial distortion, the above tests showed that a high sensitivity CMOS APS array holds great promise as a direct detection device for electron microscopy.

  15. Active pixel sensor having intra-pixel charge transfer with analog-to-digital converter

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R. (Inventor); Mendis, Sunetra K. (Inventor); Pain, Bedabrata (Inventor); Nixon, Robert H. (Inventor); Zhou, Zhimin (Inventor)

    2000-01-01

    An imaging device formed as a monolithic complementary metal oxide semiconductor Integrated circuit in an industry standard complementary metal oxide semiconductor process, the integrated circuit including a focal plane array of pixel cells, each one of the cells including a photogate overlying the substrate for accumulating photo-generated charge in an underlying portion of the substrate, a readout circuit including at least an output field effect transistor formed in the substrate, and a charge coupled device section formed on the substrate adjacent the photogate having a sensing node connected to the output transistor and at least one charge coupled device stage for transferring charge from the underlying portion of the substrate to the sensing node and an analog-to-digital converter formed in the substrate connected to the output of the readout circuit.

  16. Active pixel sensor having intra-pixel charge transfer with analog-to-digital converter

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R. (Inventor); Mendis, Sunetra K. (Inventor); Pain, Bedabrata (Inventor); Nixon, Robert H. (Inventor); Zhou, Zhimin (Inventor)

    2003-01-01

    An imaging device formed as a monolithic complementary metal oxide semiconductor integrated circuit in an industry standard complementary metal oxide semiconductor process, the integrated circuit including a focal plane array of pixel cells, each one of the cells including a photogate overlying the substrate for accumulating photo-generated charge in an underlying portion of the substrate, a readout circuit including at least an output field effect transistor formed in the substrate, and a charge coupled device section formed on the substrate adjacent the photogate having a sensing node connected to the output transistor and at least one charge coupled device stage for transferring charge from the underlying portion of the substrate to the sensing node and an analog-to-digital converter formed in the substrate connected to the output of the readout circuit.

  17. CAOS-CMOS camera.

    PubMed

    Riza, Nabeel A; La Torre, Juan Pablo; Amin, M Junaid

    2016-06-13

    Proposed and experimentally demonstrated is the CAOS-CMOS camera design that combines the coded access optical sensor (CAOS) imager platform with the CMOS multi-pixel optical sensor. The unique CAOS-CMOS camera engages the classic CMOS sensor light staring mode with the time-frequency-space agile pixel CAOS imager mode within one programmable optical unit to realize a high dynamic range imager for extreme light contrast conditions. The experimentally demonstrated CAOS-CMOS camera is built using a digital micromirror device, a silicon point-photo-detector with a variable gain amplifier, and a silicon CMOS sensor with a maximum rated 51.3 dB dynamic range. White light imaging of three different brightness simultaneously viewed targets, that is not possible by the CMOS sensor, is achieved by the CAOS-CMOS camera demonstrating an 82.06 dB dynamic range. Applications for the camera include industrial machine vision, welding, laser analysis, automotive, night vision, surveillance and multispectral military systems. PMID:27410361

  18. All-CMOS night vision viewer with integrated microdisplay

    NASA Astrophysics Data System (ADS)

    Goosen, Marius E.; Venter, Petrus J.; du Plessis, Monuko; Faure, Nicolaas M.; Janse van Rensburg, Christo; Rademeyer, Pieter

    2014-02-01

    The unrivalled integration potential of CMOS has made it the dominant technology for digital integrated circuits. With the advent of visible light emission from silicon through hot carrier electroluminescence, several applications arose, all of which rely upon the advantages of mature CMOS technologies for a competitive edge in a very active and attractive market. In this paper we present a low-cost night vision viewer which employs only standard CMOS technologies. A commercial CMOS imager is utilized for near infrared image capturing with a 128x96 pixel all-CMOS microdisplay implemented to convey the image to the user. The display is implemented in a standard 0.35 μm CMOS process, with no process alterations or post processing. The display features a 25 μm pixel pitch and a 3.2 mm x 2.4 mm active area, which through magnification presents the virtual image to the user equivalent of a 19-inch display viewed from a distance of 3 meters. This work represents the first application of a CMOS microdisplay in a low-cost consumer product.

  19. High Chromaticity Aluminum Plasmonic Pixels for Active Liquid Crystal Displays.

    PubMed

    Olson, Jana; Manjavacas, Alejandro; Basu, Tiyash; Huang, Da; Schlather, Andrea E; Zheng, Bob; Halas, Naomi J; Nordlander, Peter; Link, Stephan

    2016-01-26

    Chromatic devices such as flat panel displays could, in principle, be substantially improved by incorporating aluminum plasmonic nanostructures instead of conventional chromophores that are susceptible to photobleaching. In nanostructure form, aluminum is capable of producing colors that span the visible region of the spectrum while contributing exceptional robustness, low cost, and streamlined manufacturability compatible with semiconductor manufacturing technology. However, individual aluminum nanostructures alone lack the vivid chromaticity of currently available chromophores because of the strong damping of the aluminum plasmon resonance in the visible region of the spectrum. In recent work, we showed that pixels formed by periodic arrays of Al nanostructures yield far more vivid coloration than the individual nanostructures. This progress was achieved by exploiting far-field diffractive coupling, which significantly suppresses the scattering response on the long-wavelength side of plasmonic pixel resonances. In the present work, we show that by utilizing another collective coupling effect, Fano interference, it is possible to substantially narrow the short-wavelength side of the pixel spectral response. Together, these two complementary effects provide unprecedented control of plasmonic pixel spectral line shape, resulting in aluminum pixels with far more vivid, monochromatic coloration across the entire RGB color gamut than previously attainable. We further demonstrate that pixels designed in this manner can be used directly as switchable elements in liquid crystal displays and determine the minimum and optimal numbers of nanorods required in an array to achieve good color quality and intensity. PMID:26639191

  20. A novel position and time sensing active pixel sensor with field-assisted electron collection for charged particle tracking and electron microscopy

    NASA Astrophysics Data System (ADS)

    De Geronimo, G.; Deptuch, G.; Dragone, A.; Radeka, V.; Rehak, P.; Castoldi, A.; Fazzi, A.; Gatti, E.; Guazzoni, C.; Rijssenbeek, M.; Dulinski, W.; Besson, A.; Deveaux, M.; Winter, M.

    2006-11-01

    A new type of active pixel sensors (APSs) to track charged particles for particle physics experiments or to count number of electrons that cross any pixel at the focal plane of electron microscopes is described. The electric field of desirable shape is created inside the active volume of the pixel introducing the drift component in the movement of the signal electrons towards charge collecting electrodes. The electric field results from the flow of ˜100 mA/cm 2 hole currents within individual pixels of the sensor. The proposed sensor is produced using a standard industrially available complementary metal oxide silicon (CMOS) process. There are two main advantages of the proposed detectors when compared to the present (February 2005) state-of-the-art, i.e. field-free APS sensors. The first advantage of a field-assisted transport mechanism is the reduction of the charge collection time and of the sharing of the signal electrons between adjacent pixels by diffusion. The second advantage is the freedom to use both kinds of MOS transistors within each pixel of the sensor. Thus, the full functional power of CMOS circuits can be embedded in situ. As an example, 16-bit scalers will be implemented in each pixel of the sensor for electron microscopy. The reduced collection time combined with the state-of-the-art electronics within each pixel provides the most complete information about the position and the timing of incident charged particles for particle physics experiments. Position resolution of new sensors was computationally simulated to be a few microns, that is, the same as the resolution of standard APSs. Moreover, the active depth of the sensor and the associate electronics is less than about 20 μm and a thinned down sensor together with its beryllium backing can have a total thickness of less than 0.1% of one radiation length. The reduction of the thickness of the detector reduces the amount of multiple scattering within the detector. The determination of the

  1. Active pixel as dosimetric device for interventional radiology

    NASA Astrophysics Data System (ADS)

    Servoli, L.; Baldaccini, F.; Biasini, M.; Checcucci, B.; Chiocchini, S.; Cicioni, R.; Conti, E.; Di Lorenzo, R.; Dipilato, A. C.; Esposito, A.; Fanó, L.; Paolucci, M.; Passeri, D.; Pentiricci, A.; Placidi, P.

    2013-08-01

    Interventional Radiology (IR) is a subspecialty of radiology comprehensive of all minimally invasive diagnostic and therapeutic procedures performed using radiological devices to obtain image guidance. The interventional procedures are potentially harmful for interventional radiologists and medical staff due to the X-ray diffusion by the patient's body. The characteristic energy range of the diffused photons spans few tens of keV. In this work we will present a proposal for a new X-ray sensing element in the energy range of interest for IR procedures. The sensing element will then be assembled in a dosimeter prototype, capable of real-time measurement, packaged in a small form-factor, with wireless communication and no external power supply to be used for individual operators dosimetry for IR procedures. For the sensor, which is the heart of the system, we considered three different Active Pixel Sensors (APS). They have shown a good capability as single X-ray photon detectors, up to several tens keV photon energy. Two dosimetric quantities have been considered, the number of detected photons and the measured energy deposition. Both observables have a linear dependence with the dose, as measured by commercial dosimeters. The uncertainties in the measurement are dominated by statistic and can be pushed at ˜5% for all the sensors under test.

  2. Active pixel imagers incorporating pixel-level amplifiers based on polycrystalline-silicon thin-film transistors

    SciTech Connect

    El-Mohri, Youcef; Antonuk, Larry E.; Koniczek, Martin; Zhao Qihua; Li Yixin; Street, Robert A.; Lu Jengping

    2009-07-15

    Active matrix, flat-panel imagers (AMFPIs) employing a 2D matrix of a-Si addressing TFTs have become ubiquitous in many x-ray imaging applications due to their numerous advantages. However, under conditions of low exposures and/or high spatial resolution, their signal-to-noise performance is constrained by the modest system gain relative to the electronic additive noise. In this article, a strategy for overcoming this limitation through the incorporation of in-pixel amplification circuits, referred to as active pixel (AP) architectures, using polycrystalline-silicon (poly-Si) TFTs is reported. Compared to a-Si, poly-Si offers substantially higher mobilities, enabling higher TFT currents and the possibility of sophisticated AP designs based on both n- and p-channel TFTs. Three prototype indirect detection arrays employing poly-Si TFTs and a continuous a-Si photodiode structure were characterized. The prototypes consist of an array (PSI-1) that employs a pixel architecture with a single TFT, as well as two arrays (PSI-2 and PSI-3) that employ AP architectures based on three and five TFTs, respectively. While PSI-1 serves as a reference with a design similar to that of conventional AMFPI arrays, PSI-2 and PSI-3 incorporate additional in-pixel amplification circuitry. Compared to PSI-1, results of x-ray sensitivity demonstrate signal gains of {approx}10.7 and 20.9 for PSI-2 and PSI-3, respectively. These values are in reasonable agreement with design expectations, demonstrating that poly-Si AP circuits can be tailored to provide a desired level of signal gain. PSI-2 exhibits the same high levels of charge trapping as those observed for PSI-1 and other conventional arrays employing a continuous photodiode structure. For PSI-3, charge trapping was found to be significantly lower and largely independent of the bias voltage applied across the photodiode. MTF results indicate that the use of a continuous photodiode structure in PSI-1, PSI-2, and PSI-3 results in optical

  3. Active pixel imagers incorporating pixel-level amplifiers based on polycrystalline-silicon thin-film transistors

    PubMed Central

    El-Mohri, Youcef; Antonuk, Larry E.; Koniczek, Martin; Zhao, Qihua; Li, Yixin; Street, Robert A.; Lu, Jeng-Ping

    2009-01-01

    Active matrix, flat-panel imagers (AMFPIs) employing a 2D matrix of a-Si addressing TFTs have become ubiquitous in many x-ray imaging applications due to their numerous advantages. However, under conditions of low exposures and∕or high spatial resolution, their signal-to-noise performance is constrained by the modest system gain relative to the electronic additive noise. In this article, a strategy for overcoming this limitation through the incorporation of in-pixel amplification circuits, referred to as active pixel (AP) architectures, using polycrystalline-silicon (poly-Si) TFTs is reported. Compared to a-Si, poly-Si offers substantially higher mobilities, enabling higher TFT currents and the possibility of sophisticated AP designs based on both n- and p-channel TFTs. Three prototype indirect detection arrays employing poly-Si TFTs and a continuous a-Si photodiode structure were characterized. The prototypes consist of an array (PSI-1) that employs a pixel architecture with a single TFT, as well as two arrays (PSI-2 and PSI-3) that employ AP architectures based on three and five TFTs, respectively. While PSI-1 serves as a reference with a design similar to that of conventional AMFPI arrays, PSI-2 and PSI-3 incorporate additional in-pixel amplification circuitry. Compared to PSI-1, results of x-ray sensitivity demonstrate signal gains of ∼10.7 and 20.9 for PSI-2 and PSI-3, respectively. These values are in reasonable agreement with design expectations, demonstrating that poly-Si AP circuits can be tailored to provide a desired level of signal gain. PSI-2 exhibits the same high levels of charge trapping as those observed for PSI-1 and other conventional arrays employing a continuous photodiode structure. For PSI-3, charge trapping was found to be significantly lower and largely independent of the bias voltage applied across the photodiode. MTF results indicate that the use of a continuous photodiode structure in PSI-1, PSI-2, and PSI-3 results in optical fill

  4. Passive radiation detection using optically active CMOS sensors

    NASA Astrophysics Data System (ADS)

    Dosiek, Luke; Schalk, Patrick D.

    2013-05-01

    Recently, there have been a number of small-scale and hobbyist successes in employing commodity CMOS-based camera sensors for radiation detection. For example, several smartphone applications initially developed for use in areas near the Fukushima nuclear disaster are capable of detecting radiation using a cell phone camera, provided opaque tape is placed over the lens. In all current useful implementations, it is required that the sensor not be exposed to visible light. We seek to build a system that does not have this restriction. While building such a system would require sophisticated signal processing, it would nevertheless provide great benefits. In addition to fulfilling their primary function of image capture, cameras would also be able to detect unknown radiation sources even when the danger is considered to be low or non-existent. By experimentally profiling the image artifacts generated by gamma ray and β particle impacts, algorithms are developed to identify the unique features of radiation exposure, while discarding optical interaction and thermal noise effects. Preliminary results focus on achieving this goal in a laboratory setting, without regard to integration time or computational complexity. However, future work will seek to address these additional issues.

  5. SOI monolithic pixel detector

    NASA Astrophysics Data System (ADS)

    Miyoshi, T.; Ahmed, M. I.; Arai, Y.; Fujita, Y.; Ikemoto, Y.; Takeda, A.; Tauchi, K.

    2014-05-01

    We are developing monolithic pixel detector using fully-depleted (FD) silicon-on-insulator (SOI) pixel process technology. The SOI substrate is high resistivity silicon with p-n junctions and another layer is a low resistivity silicon for SOI-CMOS circuitry. Tungsten vias are used for the connection between two silicons. Since flip-chip bump bonding process is not used, high sensor gain in a small pixel area can be obtained. In 2010 and 2011, high-resolution integration-type SOI pixel sensors, DIPIX and INTPIX5, have been developed. The characterizations by evaluating pixel-to-pixel crosstalk, quantum efficiency (QE), dark noise, and energy resolution were done. A phase-contrast imaging was demonstrated using the INTPIX5 pixel sensor for an X-ray application. The current issues and future prospect are also discussed.

  6. Improved AC pixel electrode circuit for active matrix of organic light-emitting display

    NASA Astrophysics Data System (ADS)

    Si, Yujuan; Lang, Liuqi; Chen, Wanzhong; Liu, Shiyong

    2004-05-01

    In this paper, a modified four-transistor pixel circuit for active-matrix organic light-emitting displays (AMOLED) was developed to improve the performance of OLED device. This modified pixel circuit can provide an AC driving mode to make the OLED working in a reversed-biased voltage during the certain cycle. The optimized values of the reversed-biased voltage and the characteristics of the pixel circuit were investigated using AIM-SPICE. The simulated results reveal that this circuit can provide a suitable output current and voltage characteristic, and little change was made in luminance current.

  7. The RD50 activity in the context of future pixel detector systems

    NASA Astrophysics Data System (ADS)

    Casse, G.

    2015-05-01

    The CERN/RD50 collaboration is dedicated to the radiation hardening of semiconductor sensors for future super-collider needs. The findings of this collaboration are therefore especially relevant to the pixel devices for the LHC experiment upgrades. A considerable amount of results on the enhancement of the radiation tolerance of silicon sensors has been found within RD50. The research towards radiation hardening has highlighted, and increased the knowledge on properties of sensors that are relevant to other applications. For example radiation hardening relies on the speed of signal collection in irradiated devices. As a consequence, the methods envisaged for increasing this collection speed turn out to be promising for significantly improving the performance of time resolved, high spatial resolution systems. A new type of device processing strongly emerging for production of future pixel sensor systems is the HV-CMOS technology. The RD50 research methodology provides the tools for characterising the behaviour of the deep collecting electrode (deep n-well) for this type of device after irradiation and the optimal framework for comparing the performance of the new devices with the current state of the art.

  8. Radiation hardness of a 180 nm SOI monolithic active pixel sensor

    NASA Astrophysics Data System (ADS)

    Fernandez-Perez, S.; Backhaus, M.; Pernegger, H.; Hemperek, T.; Kishishita, T.; Krüger, H.; Wermes, N.

    2015-10-01

    The use of Silicon-on-Insulator (SOI) technology as a particle detector in a high radiation environment is, at present, limited mostly by radiation effects on the transistor characteristics, back gate effect, and mutual coupling between the Buried Oxide (BOX) and the sensor. We have fabricated and tested a new 0.18 μm SOI CMOS monolithic pixel sensor using the XFAB process. In contrast to the most commonly used SOI technologies, this particular technology uses partially depleted SOI transistors, offering a double well structure, which shields the thin gate oxide transistors from the BOX. In addition, an increased distance between transistors and a thicker BOX than has been previously used offers promising solutions to the performance limitations mentioned above. The process further allows the use of high voltages (up to 200 V), which are used to partially deplete the substrate. Thus, the newly fabricated device in the XFAB process is especially interesting for applications in extremely high radiation environments, such as LHC experiments. A four stage validation programme of the technology and the fabricated monolithic pixel sensor has been performed and its results are shown in this paper. The first targets radiation hardness of the transistor characteristics up to 700 Mrad, the second investigates the existence of the back gate effect, the third one targets the coupling between the BOX and the sensor, and the fourth investigates the characterization of charge collection in the sensor diode below the BOX.

  9. Assessing design activity in complex CMOS circuit design

    NASA Astrophysics Data System (ADS)

    Biswas, Gautam; Goldman, Susan R.; Fisher, Doug; Bhuva, Bharat; Glewwe, Grant

    1994-03-01

    This chapter characterizes human problem solving in digital circuit design. We analyze protocols of designers with varying degrees of training, identifying problem solving strategies used by these designers, discuss activity patterns that differentiate designers, and propose these as a tentative basis for assessing expertise in digital design. Throughout, we argue that a comprehensive model of human design should integrate a variety of strategies, which heretofore have been proposed as individually sufficient models of human design problem solving. We close by describing an automated tool for design and its assessment.

  10. CMOS-liquid-crystal-based image transceiver device

    NASA Astrophysics Data System (ADS)

    Efron, Uzi; Davidov, Isak; Sinelnikov, Vladimir; Levin, Ilya

    2001-05-01

    A CMOS-Liquid Crystal-Based Image Transceiver Device (ITD) is under development at the Holon Institute of Technology. The device combines both functions of imaginary and display in a single array structure. This unique structure allows the combination of see-through, aiming, imaging and the displaying of a superposed image to be combined in a single, compact, head mounted display. The CMOS-based pixel elements are designed to provide image sensor part of the pixel is based on an n-well photodiode and a three-transistors readout circuit. The imaging function is based on a back- illuminated sensor configuration. In order to provide a high imager fill-factor, two pixel configuration are proposed: 1) A p++/p-/p-well silicon structure using twin- well CMOS process; 2) an n-well processed silicon structure with a micro-lens array. The display portion of the IT device is to be fabricate don a silicon-based reflective, active matrix driver, using nematic liquid crystal material. The reflective display pixel electrode is driven by an n-MOS transistor, formed in the corresponding pixel region on the silicon substrate. The timing, sequencing and control of the IT device array are designed in a pipeline array processing scheme. A preliminary prototype system and device design have been performed and the first test device is currently being tested. Details of the device design as well as its smart goggle applications are presented.

  11. High-performance monolithic CMOS detectors for space applications

    NASA Astrophysics Data System (ADS)

    Saint-Pe, Olivier; Tulet, Michel; Davancens, Robert; Larnaudie, Franck; Vignon, Bruno; Magnan, Pierre; Farre, Jean A.; Corbiere, Franck; Martin-Gonthier, Philippe

    2001-12-01

    During the last 10 years, research about CMOS image sensors (also called APS - Active Pixel Sensors) has been intensively carried out, in order to offer an alternative to CCDs as image sensors. This is particularly the case for space applications as CMOS image sensors feature characteristics which are obviously of interest for flight hardware: parallel or semi-parallel architecture, on chip control and processing electronics, low power dissipation, high level of radiation tolerance... Many image sensor companies, institutes and laboratories have demonstrated the compatibility of CMOS image sensors with consumer applications: micro-cameras, video-conferencing, digital- still cameras. And recent designs have shown that APS is getting closer to the CCD in terms of performance level. However, he large majority of the existing products do not offer the specific features which are required for many space applications. ASTRIUM and SUPAERO/CIMI have decided to work together in view of developing CMOS image sensors dedicated to space business. After a brief presentation of the team organization for space image sensor design and production, the latest results of a high performances 512 X 512 pixels CMOS device characterization are presented with emphasis on the achieved electro-optical performance. Finally, the on going and short-term coming activities of the team are discussed.

  12. Design and Fabrication of Vertically-Integrated CMOS Image Sensors

    PubMed Central

    Skorka, Orit; Joseph, Dileepan

    2011-01-01

    Technologies to fabricate integrated circuits (IC) with 3D structures are an emerging trend in IC design. They are based on vertical stacking of active components to form heterogeneous microsystems. Electronic image sensors will benefit from these technologies because they allow increased pixel-level data processing and device optimization. This paper covers general principles in the design of vertically-integrated (VI) CMOS image sensors that are fabricated by flip-chip bonding. These sensors are composed of a CMOS die and a photodetector die. As a specific example, the paper presents a VI-CMOS image sensor that was designed at the University of Alberta, and fabricated with the help of CMC Microsystems and Micralyne Inc. To realize prototypes, CMOS dies with logarithmic active pixels were prepared in a commercial process, and photodetector dies with metal-semiconductor-metal devices were prepared in a custom process using hydrogenated amorphous silicon. The paper also describes a digital camera that was developed to test the prototype. In this camera, scenes captured by the image sensor are read using an FPGA board, and sent in real time to a PC over USB for data processing and display. Experimental results show that the VI-CMOS prototype has a higher dynamic range and a lower dark limit than conventional electronic image sensors. PMID:22163860

  13. Small-Scale Readout Systems Prototype for the STAR PIXEL Detector

    SciTech Connect

    Szelezniak, Michal A.; Besson, Auguste; Colledani, Claude; Dorokhov, Andrei; Dulinski, Wojciech; Greiner, Leo C.; Himmi, Abdelkader; Hu, Christine; Matis, Howard S.; Ritter, Hans Georg; Rose, Andrew; Shabetai, Alexandre; Stezelberger, Thorsten; Sun, Xiangming; Thomas, Jim H.; Valin, Isabelle; Vu, Chinh Q.; Wieman, Howard H.; Winter, Marc

    2008-10-01

    A prototype readout system for the STAR PIXEL detector in the Heavy Flavor Tracker (HFT) vertex detector upgrade is presented. The PIXEL detector is a Monolithic Active Pixel Sensor (MAPS) based silicon pixel vertex detector fabricated in a commercial CMOS process that integrates the detector and front-end electronics layers in one silicon die. Two generations ofMAPS prototypes designed specifically for the PIXEL are discussed. We have constructed a prototype telescope system consisting of three small MAPS sensors arranged in three parallel and coaxial planes with a readout system based on the readout architecture for PIXEL. This proposed readout architecture is simple and scales to the size required to readout the final detector. The real-time hit finding algorithm necessary for data rate reduction in the 400 million pixel detector is described, and aspects of the PIXEL system integration into the existing STAR framework are addressed. The complete system has been recently tested and shown to be fully functional.

  14. Wide tuning-range CMOS VCO based on a tunable active inductor

    NASA Astrophysics Data System (ADS)

    Babaei Kia, Hojjat; Khari A'ain, Abu; Grout, Ian

    2014-01-01

    In this paper, a wide tuning-range CMOS voltage-controlled oscillator (VCO) with high output power using an active inductor circuit is presented. In this VCO design, the coarse frequency is achieved by tuning the integrated active inductor. The circuit has been simulated using a 0.18-µm CMOS fabrication process and presents output frequency range from 100 MHz to 2.5 GHz, resulting in a tuning range of 96%. The phase noise is -85 dBc/Hz at a 1 MHz frequency offset. The output power is from -3 dBm at 2.55 GHz to +14 dBm at 167 MHz. The active inductor power dissipation is 6.5 mW and the total power consumption is 16.27 mW when operating on a 1.8 V supply voltage. By comparing this active inductor architecture VCO with general VCO topology, the result shows that this topology, which employs the proposed active inductor, produces a better performance.

  15. A novel colour-sensitive CMOS detector

    NASA Astrophysics Data System (ADS)

    Langfelder, G.; Longoni, A.; Zaraga, F.

    2009-10-01

    A novel colour-sensitive semiconductor detector is proposed. The device (named Transverse Field Detector (TFD)) can be used to measure the colour of the incident light without any colour filter. The device is completely compatible with standard CMOS processes and is suitable to be integrated in a pixel array for imaging purposes. The working principle is based on the capability of this device to collect at different superficial junctions the carriers, generated at different depths, by means of suitable transverse electric fields. The transverse components of the electric field are generated inside the depleted region by a suitable bias of the superficial junctions. Thanks to the differences in the light absorption coefficients at different wavelengths, the device performs colour separation. Among the advantages of this approach are the capability of an active tuning of the pixel colour response, which can be obtained just by changing the biasing values of collecting junctions, and foreseen higher colour fidelity, thanks to the easy extension to four colour pixels. First test structures of three colours TFD pixels were designed and built in a standard CMOS 90 nm technology. Operative principles of the device and first experimental results are presented.

  16. Improved Space Object Observation Techniques Using CMOS Detectors

    NASA Astrophysics Data System (ADS)

    Schildknecht, T.; Hinze, A.; Schlatter, P.; Silha, J.; Peltonen, J.; Santti, T.; Flohrer, T.

    2013-08-01

    CMOS-sensors, or in general Active Pixel Sensors (APS), are rapidly replacing CCDs in the consumer camera market. Due to significant technological advances during the past years these devices start to compete with CCDs also for demanding scientific imaging applications, in particular in the astronomy community. CMOS detectors offer a series of inherent advantages compared to CCDs, due to the structure of their basic pixel cells, which each contain their own amplifier and readout electronics. The most prominent advantages for space object observations are the extremely fast and flexible readout capabilities, feasibility for electronic shuttering and precise epoch registration, and the potential to perform image processing operations on-chip and in real-time. Presently applied and proposed optical observation strategies for space debris surveys and space surveillance applications had to be analyzed. The major design drivers were identified and potential benefits from using available and future CMOS sensors were assessed. The major challenges and design drivers for ground-based and space-based optical observation strategies have been analyzed. CMOS detector characteristics were critically evaluated and compared with the established CCD technology, especially with respect to the above mentioned observations. Similarly, the desirable on-chip processing functionalities which would further enhance the object detection and image segmentation were identified. Finally, the characteristics of a particular CMOS sensor available at the Zimmerwald observatory were analyzed by performing laboratory test measurements.

  17. CMOS-sensors for energy-resolved X-ray imaging

    NASA Astrophysics Data System (ADS)

    Doering, D.; Amar-Youcef, S.; Baudot, J.; Deveaux, M.; Dulinski, W.; Kachel, M.; Linnik, B.; Müntz, C.; Stroth, Joachim

    2016-01-01

    Due to their low noise, CMOS Monolithic Active Pixel Sensors are suited to sense X-rays with a few keV quantum energy, which is of interest for high resolution X-ray imaging. Moreover, the good energy resolution of the silicon sensors might be used to measure this quantum energy. Combining both features with the good spatial resolution of CMOS sensors opens the potential to build ``color sensitive" X-ray cameras. Taking such colored images is hampered by the need to operate the CMOS sensors in a single photon counting mode, which restricts the photon flux capability of the sensors. More importantly, the charge sharing between the pixels smears the potentially good energy resolution of the sensors. Based on our experience with CMOS sensors for charged particle tracking, we studied techniques to overcome the latter by means of an offline processing of the data obtained from a CMOS sensor prototype. We found that the energy resolution of the pixels can be recovered at the expense of reduced quantum efficiency. We will introduce the results of our study and discuss the feasibility of taking colored X-ray pictures with CMOS sensors.

  18. Imaging of moving fiducial markers during radiotherapy using a fast, efficient active pixel sensor based EPID

    SciTech Connect

    Osmond, John P. F.; Zin, Hafiz M.; Harris, Emma J.; Lupica, Giovanni; Allinson, Nigel M.; Evans, Philip M.

    2011-11-15

    Purpose: The purpose of this work was to investigate the use of an experimental complementary metal-oxide-semiconductor (CMOS) active pixel sensor (APS) for tracking of moving fiducial markers during radiotherapy. Methods: The APS has an active area of 5.4 x 5.4 cm and maximum full frame read-out rate of 20 frame s{sup -1}, with the option to read out a region-of-interest (ROI) at an increased rate. It was coupled to a 4 mm thick ZnWO4 scintillator which provided a quantum efficiency (QE) of 8% for a 6 MV x-ray treatment beam. The APS was compared with a standard iViewGT flat panel amorphous Silicon (a-Si) electronic portal imaging device (EPID), with a QE of 0.34% and a frame-rate of 2.5 frame s{sup -1}. To investigate the ability of the two systems to image markers, four gold cylinders of length 8 mm and diameter 0.8, 1.2, 1.6, and 2 mm were placed on a motion-platform. Images of the stationary markers were acquired using the APS at a frame-rate of 20 frame s{sup -1}, and a dose-rate of 143 MU min{sup -1} to avoid saturation. EPID images were acquired at the maximum frame-rate of 2.5 frame s{sup -1}, and a reduced dose-rate of 19 MU min{sup -1} to provide a similar dose per frame to the APS. Signal-to-noise ratio (SNR) of the background signal and contrast-to-noise ratio (CNR) of the marker signal relative to the background were evaluated for both imagers at doses of 0.125 to 2 MU. Results: Image quality and marker visibility was found to be greater in the APS with SNR {approx}5 times greater than in the EPID and CNR up to an order of magnitude greater for all four markers. To investigate the ability to image and track moving markers the motion-platform was moved to simulate a breathing cycle with period 6 s, amplitude 20 mm and maximum speed 13.2 mm s{sup -1}. At the minimum integration time of 50 ms a tracking algorithm applied to the APS data found all four markers with a success rate of {>=}92% and positional error {<=}90 {mu}m. At an integration time of 400

  19. Active pixels of transverse field detector based on a charge preamplifier

    NASA Astrophysics Data System (ADS)

    Langfelder, G.; Buffa, C.; Longoni, A. F.; Pelamatti, A.; Zaraga, F.

    2012-01-01

    The Transverse Field Detector (TFD), a filter-less and tunable color sensitive pixel, is based on the generation of specific electric field configurations within a depleted Silicon volume. Each field configuration determines a set of three or more spectral responses that can be used for direct color acquisition at each pixel position. In order to avoid unpredictable changes of the electric field configuration during the single image capture, a specific active pixel (AP) has been designed. In this AP the dark- and photo-generated charge is not integrated directly on the junction capacitance, but, for each color, it is integrated on the feedback capacitance of a single-transistor charge pre-amplifier. The AP further includes a bias transistor, a reset transistor and a follower. In this work the design of such a pixel is discussed and the experimental results obtained on a 2x2 matrix of these active pixels are analyzed in terms of spectral response, linearity, noise, dynamic range and repeatability.

  20. Further developments on a novel color sensitive CMOS detector

    NASA Astrophysics Data System (ADS)

    Langfelder, G.; Longoni, A.; Zaraga, F.

    2009-05-01

    The Transverse Field Detector (TFD) is a recently proposed Silicon pixel device designed to perform color imaging without the use of color filters. The color detection principle is based on the dependence of the Silicon absorption coefficient from the wavelength and relies on the generation of a suitable transverse electric field configuration, within the semiconductor active layer, to drive photocarriers generated at different depths towards different collecting electrodes. Each electrode has in this way a different spectral response with respect to the incoming wavelength. Pixels with three or four different spectral responses can be implemented within ~ 6 μm of pixel dimension. Thanks to the compatibility with standard triple well CMOS processes, the TFD can be used in an Active Pixel Sensor exploiting a dedicated readout topology, based on a single transistor charge amplifier. The overall APS electronics includes five transistors (5T) and a feedback capacitance, with a resulting overall fill factor around 50%. In this work the three colors and four colors TFD pixel simulations and implementations in a 90 nm standard CMOS triple well technology are described. Details on the design of a TFD APS mini matrix are provided and preliminary experimental results on four colors pixels are presented.

  1. Characterisation of Vanilla—A novel active pixel sensor for radiation detection

    NASA Astrophysics Data System (ADS)

    Blue, A.; Bates, R.; Laing, A.; Maneuski, D.; O'Shea, V.; Clark, A.; Prydderch, M.; Turchetta, R.; Arvanitis, C.; Bohndiek, S.

    2007-10-01

    Novel features of a new monolithic active pixel sensor, Vanilla, with 520×520 pixels ( 25 μm square) has been characterised for the first time. Optimisation of the sensor operation was made through variation of frame rates, integration times and on-chip biases and voltages. Features such as flushed reset operation, ROI capturing and readout modes have been fully tested. Stability measurements were performed to test its suitablility for long-term applications. These results suggest the Vanilla sensor—along with bio-medical and space applications—is suitable for use in particle physics experiments.

  2. Contact CMOS imaging of gaseous oxygen sensor array

    PubMed Central

    Daivasagaya, Daisy S.; Yao, Lei; Yi Yung, Ka; Hajj-Hassan, Mohamad; Cheung, Maurice C.; Chodavarapu, Vamsy P.; Bright, Frank V.

    2014-01-01

    We describe a compact luminescent gaseous oxygen (O2) sensor microsystem based on the direct integration of sensor elements with a polymeric optical filter and placed on a low power complementary metal-oxide semiconductor (CMOS) imager integrated circuit (IC). The sensor operates on the measurement of excited-state emission intensity of O2-sensitive luminophore molecules tris(4,7-diphenyl-1,10-phenanthroline) ruthenium(II) ([Ru(dpp)3]2+) encapsulated within sol–gel derived xerogel thin films. The polymeric optical filter is made with polydimethylsiloxane (PDMS) that is mixed with a dye (Sudan-II). The PDMS membrane surface is molded to incorporate arrays of trapezoidal microstructures that serve to focus the optical sensor signals on to the imager pixels. The molded PDMS membrane is then attached with the PDMS color filter. The xerogel sensor arrays are contact printed on top of the PDMS trapezoidal lens-like microstructures. The CMOS imager uses a 32 × 32 (1024 elements) array of active pixel sensors and each pixel includes a high-gain phototransistor to convert the detected optical signals into electrical currents. Correlated double sampling circuit, pixel address, digital control and signal integration circuits are also implemented on-chip. The CMOS imager data is read out as a serial coded signal. The CMOS imager consumes a static power of 320 µW and an average dynamic power of 625 µW when operating at 100 Hz sampling frequency and 1.8 V DC. This CMOS sensor system provides a useful platform for the development of miniaturized optical chemical gas sensors. PMID:24493909

  3. Programmable active pixel sensor to investigate neural interactions within the retina

    NASA Astrophysics Data System (ADS)

    Hart, Matthew D.; Prydderch, Mark L.; Morrison, James D.; Murdoch, Derek; Mathieson, Keith

    2009-05-01

    Detection of the visual scene by the eye and the resultant neural interactions of the retina-brain system give us our perception of sight. We have developed an Active Pixel Sensor (APS) to be used as a tool for both furthering understanding of these interactions via experimentation with the retina and to make developments towards a realisable retinal prosthesis. The sensor consists of 469 pixels in a hexagonal array. The pixels are interconnected by a programmable neural network to mimic lateral interactions between retinal cells. Outputs from the sensor are in the form of biphasic current pulse trains suitable to stimulate retinal cells via a biocompatible array. The APS will be described with initial characterisation and test results.

  4. Low Temperature Polycrystalline Silicon Thin Film Transistor Pixel Circuits for Active Matrix Organic Light Emitting Diodes

    NASA Astrophysics Data System (ADS)

    Fan, Ching-Lin; Lin, Yu-Sheng; Liu, Yan-Wei

    A new pixel design and driving method for active matrix organic light emitting diode (AMOLED) displays that use low-temperature polycrystalline silicon thin-film transistors (LTPS-TFTs) with a voltage programming method are proposed and verified using the SPICE simulator. We had employed an appropriate TFT model in SPICE simulation to demonstrate the performance of the pixel circuit. The OLED anode voltage variation error rates are below 0.35% under driving TFT threshold voltage deviation (Δ Vth =± 0.33V). The OLED current non-uniformity caused by the OLED threshold voltage degradation (Δ VTO =+0.33V) is significantly reduced (below 6%). The simulation results show that the pixel design can improve the display image non-uniformity by compensating for the threshold voltage deviation in the driving TFT and the OLED threshold voltage degradation at the same time.

  5. Full colour RGB OLEDs on CMOS for active-matrix OLED microdisplays

    NASA Astrophysics Data System (ADS)

    Kreye, D.; Toerker, M.; Vogel, U.; Amelung, J.

    2006-08-01

    Microdisplays are used in various optical devices such as headsets, viewfinders and helmet-mounted displays. The use of organic light emitting diodes (OLEDs) in a microdisplay on silicone substrate provides the opportunity of lower power consumption and higher optical performance compared to other near-to-eye display technologies. Highly efficient, low-voltage, top emitting OLEDs are well suitable for the integration into a CMOSprocess. By reducing the operating voltage for the OLEDs below 5V, the costs for the CMOS process can be reduced significantly, because a standard process without high-voltage option can be used. Various OLED stacks on silicone substrate are presented, suitable for full colour (RGB) applications. Red and green emitting phosphorescent OLEDs and blue emitting fluorescent OLEDs all with doped charge transport layers were prepared on a two metal layer CMOS test substrate without active transistor area. Afterwards, the different test displays were measured and compared with respect to their performance (current, luminance, voltage, luminance dependence on viewing angle, optical outcoupling etc.)

  6. [High-Performance Active Pixel X-Ray Sensors for X-Ray Astronomy

    NASA Technical Reports Server (NTRS)

    Bautz, Mark; Suntharalingam, Vyshnavi

    2005-01-01

    The subject grants support development of High-Performance Active Pixel Sensors for X-ray Astronomy at the Massachusetts Institute of Technology (MIT) Center for Space Research and at MIT's Lincoln Laboratory. This memo reports our progress in the second year of the project, from April, 2004 through the present.

  7. SMARTPIX, a photon-counting pixel detector for synchrotron applications based on Medipix3RX readout chip and active edge pixel sensors

    NASA Astrophysics Data System (ADS)

    Ponchut, C.; Collet, E.; Hervé, C.; Le Caer, T.; Cerrai, J.; Siron, L.; Dabin, Y.; Ribois, J. F.

    2015-01-01

    Photon-counting pixel detectors are now routinely used on synchrotron beamlines. Many applications benefit from their noiseless mode of operation, single-pixel point spread function and high frame rates. One of their drawbacks is a discontinuous detection area due to the space-consuming wirebonded connections of the readout chips. Moreover, charge sharing limits their efficiency and their energy discrimination capabilities. In order to overcome these issues the ESRF is developing SMARTPIX,a scalable and versatile pixel detector system with minimized dead areas and with energy resolving capabilities based on the MEDIPIX3RX readout chip. SMARTPIX exploits the through-silicon via technology implemented on MEDIPIX3RX, the active edge sensor processing developed in particular at ADVACAM, and the on-chip analog charge summing feature of MEDIPIX3RX. This article reports on system architecture, unit module structure, data acquisition electronics, target characteristics and applications.

  8. Heavily irradiated N-in-p thin planar pixel sensors with and without active edges

    NASA Astrophysics Data System (ADS)

    Terzo, S.; Andricek, L.; Macchiolo, A.; Moser, H. G.; Nisius, R.; Richter, R. H.; Weigell, P.

    2014-05-01

    We present the results of the characterization of silicon pixel modules employing n-in-p planar sensors with an active thickness of 150 μm, produced at MPP/HLL, and 100-200 μm thin active edge sensor devices, produced at VTT in Finland. These thin sensors are designed as candidates for the ATLAS pixel detector upgrade to be operated at the HL-LHC, as they ensure radiation hardness at high fluences. They are interconnected to the ATLAS FE-I3 and FE-I4 read-out chips. Moreover, the n-in-p technology only requires a single side processing and thereby it is a cost-effective alternative to the n-in-n pixel technology presently employed in the LHC experiments. High precision beam test measurements of the hit efficiency have been performed on these devices both at the CERN SpS and at DESY, Hamburg. We studied the behavior of these sensors at different bias voltages and different beam incident angles up to the maximum one expected for the new Insertable B-Layer of ATLAS and for HL-LHC detectors. Results obtained with 150 μm thin sensors, assembled with the new ATLAS FE-I4 chip and irradiated up to a fluence of 4 × 1015 neq/cm2, show that they are excellent candidates for larger radii of the silicon pixel tracker in the upgrade of the ATLAS detector at HL-LHC. In addition, the active edge technology of the VTT devices maximizes the active area of the sensor and reduces the material budget to suit the requirements for the innermost layers. The edge pixel performance of VTT modules has been investigated at beam test experiments and the analysis after irradiation up to a fluence of 5 × 1015 neq/cm2 has been performed using radioactive sources in the laboratory.

  9. Spectral characterisation and noise performance of Vanilla—an active pixel sensor

    NASA Astrophysics Data System (ADS)

    Blue, Andrew; Bates, R.; Bohndiek, S. E.; Clark, A.; Arvanitis, Costas D.; Greenshaw, T.; Laing, A.; Maneuski, D.; Turchetta, R.; O'Shea, V.

    2008-06-01

    This work will report on the characterisation of a new active pixel sensor, Vanilla. The Vanilla comprises of 512×512 (25μm 2) pixels. The sensor has a 12 bit digital output for full-frame mode, although it can also be readout in analogue mode, whereby it can also be read in a fully programmable region-of-interest (ROI) mode. In full frame, the sensor can operate at a readout rate of more than 100 frames per second (fps), while in ROI mode, the speed depends on the size, shape and number of ROIs. For example, an ROI of 6×6 pixels can be read at 20,000 fps in analogue mode. Using photon transfer curve (PTC) measurements allowed for the calculation of the read noise, shot noise, full-well capacity and camera gain constant of the sensor. Spectral response measurements detailed the quantum efficiency (QE) of the detector through the UV and visible region. Analysis of the ROI readout mode was also performed. Such measurements suggest that the Vanilla APS (active pixel sensor) will be suitable for a wide range of applications including particle physics and medical imaging.

  10. Active inductor based fully integrated CMOS transmit/ receive switch for 2.4 GHz RF transceiver.

    PubMed

    Bhuiyan, Mohammad A S; Zijie, Yeoh; Yu, Jae S; Reaz, Mamun B I; Kamal, Noorfazila; Chang, Tae G

    2016-05-31

    Modern Radio Frequency (RF) transceivers cannot be imagined without high-performance (Transmit/Receive) T/R switch. Available T/R switches suffer mainly due to the lack of good trade-off among the performance parameters, where high isolation and low insertion loss are very essential. In this study, a T/R switch with high isolation and low insertion loss performance has been designed by using Silterra 0.13µm CMOS process for 2.4GHz ISM band RF transceivers. Transistor aspect ratio optimization, proper gate bias resistance, resistive body floating and active inductor-based parallel resonance techniques have been implemented to achieve better trade-off. The proposed T/R switch exhibits 0.85dB insertion loss and 45.17dB isolation in both transmit and receive modes. Moreover, it shows very competitive values of power handling capability (P1dB) and linearity (IIP3) which are 11.35dBm and 19.60dBm, respectively. Due to avoiding bulky inductor and capacitor, the proposed active inductor-based T/R switch became highly compact occupying only 0.003mm2 of silicon space; which will further trim down the total cost of the transceiver. Therefore, the proposed active inductor-based T/R switch in 0.13µm CMOS process will be highly useful for the electronic industries where low-power, high-performance and compactness of devices are the crucial concerns. PMID:27254443

  11. CMOS imager for pointing and tracking applications

    NASA Technical Reports Server (NTRS)

    Pain, Bedabrata (Inventor); Sun, Chao (Inventor); Yang, Guang (Inventor); Heynssens, Julie B. (Inventor)

    2006-01-01

    Systems and techniques to realize pointing and tracking applications with CMOS imaging devices. In general, in one implementation, the technique includes: sampling multiple rows and multiple columns of an active pixel sensor array into a memory array (e.g., an on-chip memory array), and reading out the multiple rows and multiple columns sampled in the memory array to provide image data with reduced motion artifact. Various operation modes may be provided, including TDS, CDS, CQS, a tracking mode to read out multiple windows, and/or a mode employing a sample-first-read-later readout scheme. The tracking mode can take advantage of a diagonal switch array. The diagonal switch array, the active pixel sensor array and the memory array can be integrated onto a single imager chip with a controller. This imager device can be part of a larger imaging system for both space-based applications and terrestrial applications.

  12. First result on biased CMOS MAPs-on-diamond devices

    NASA Astrophysics Data System (ADS)

    Kanxheri, K.; Citroni, M.; Fanetti, S.; Lagomarsino, S.; Morozzi, A.; Parrini, G.; Passeri, D.; Sciortino, S.; Servoli, L.

    2015-10-01

    Recently a new type of device, the MAPS-on-diamond, obtained bonding a thinned to 25 μm CMOS Monolithic Active Pixel Sensor to a standard 500 μm pCVD diamond substrate, has been proposed and fabricated, allowing a highly segmented readout (10×10 μm pixel size) of the signal produced in the diamond substrate. The bonding between the two materials has been obtained using a new laser technique to deliver the needed energy at the interface. A biasing scheme has been adopted to polarize the diamond substrate to allow the charge transport inside the diamond without disrupting the functionalities of the CMOS Monolithic Active Pixel Sensor. The main concept of this class of devices is the capability of the charges generated in the diamond by ionizing radiation to cross the silicon-diamond interface and to be collected by the MAPS photodiodes. In this work we demonstrate that such passage occurs and measure its overall efficiency. This study has been carried out first calibrating the CMOS MAPS with monochromatic X-rays, and then testing the device with charged particles (electrons) either with and without biasing the diamond substrate, to compare the amount of signal collected.

  13. Characteristics of Monolithically Integrated InGaAs Active Pixel Imager Array

    NASA Technical Reports Server (NTRS)

    Kim, Q.; Cunningham, T. J.; Pain, B.; Lange, M. J.; Olsen, G. H.

    2000-01-01

    Switching and amplifying characteristics of a newly developed monolithic InGaAs Active Pixel Imager Array are presented. The sensor array is fabricated from InGaAs material epitaxially deposited on an InP substrate. It consists of an InGaAs photodiode connected to InP depletion-mode junction field effect transistors (JFETs) for low leakage, low power, and fast control of circuit signal amplifying, buffering, selection, and reset. This monolithically integrated active pixel sensor configuration eliminates the need for hybridization with silicon multiplexer. In addition, the configuration allows the sensor to be front illuminated, making it sensitive to visible as well as near infrared signal radiation. Adapting the existing 1.55 micrometer fiber optical communication technology, this integration will be an ideal system of optoelectronic integration for dual band (Visible/IR) applications near room temperature, for use in atmospheric gas sensing in space, and for target identification on earth. In this paper, two different types of small 4 x 1 test arrays will be described. The effectiveness of switching and amplifying circuits will be discussed in terms of circuit effectiveness (leakage, operating frequency, and temperature) in preparation for the second phase demonstration of integrated, two-dimensional monolithic InGaAs active pixel sensor arrays for applications in transportable shipboard surveillance, night vision, and emission spectroscopy.

  14. Development of active edge pixel sensors and four-side buttable modules using vertical integration technologies

    NASA Astrophysics Data System (ADS)

    Macchiolo, A.; Andricek, L.; Moser, H.-G.; Nisius, R.; Richter, R. H.; Terzo, S.; Weigell, P.

    2014-11-01

    We present an R&D activity focused on the development of novel modules for the upgrade of the ATLAS pixel system at the High Luminosity LHC (HL-LHC). The modules consist of n-in-p pixel sensors, 100 or 200 μm thick, produced at VTT (Finland) with an active edge technology, which considerably reduces the dead area at the periphery of the device. The sensors are interconnected with solder bump-bonding to the ATLAS FE-I3 and FE-I4 read-out chips, and characterised with radioactive sources and beam tests at the CERN-SPS and DESY. The results of these measurements will be discussed for devices before and after irradiation up to a fluence of 5 ×1015neq /cm2. We will also report on the R&D activity to obtain Inter Chip Vias (ICVs) on the ATLAS read-out chip in collaboration with the Fraunhofer Institute EMFT. This step is meant to prove the feasibility of the signal transport to the newly created readout pads on the backside of the chips allowing for four side buttable devices without the presently used cantilever for wire bonding. The read-out chips with ICVs will be interconnected to thin pixel sensors, 75 μm and 150 μm thick, with the Solid Liquid Interdiffusion (SLID) technology, which is an alternative to the standard solder bump-bonding.

  15. Dynamically re-configurable CMOS imagers for an active vision system

    NASA Technical Reports Server (NTRS)

    Yang, Guang (Inventor); Pain, Bedabrata (Inventor)

    2005-01-01

    A vision system is disclosed. The system includes a pixel array, at least one multi-resolution window operation circuit, and a pixel averaging circuit. The pixel array has an array of pixels configured to receive light signals from an image having at least one tracking target. The multi-resolution window operation circuits are configured to process the image. Each of the multi-resolution window operation circuits processes each tracking target within a particular multi-resolution window. The pixel averaging circuit is configured to sample and average pixels within the particular multi-resolution window.

  16. DEPFET Active Pixel Detectors for a Future Linear e(+}e({-)) Collider

    NASA Astrophysics Data System (ADS)

    Alonso, O.; Casanova, R.; Dieguez, A.; Dingfelder, J.; Hemperek, T.; Kishishita, T.; Kleinohl, T.; Koch, M.; Kruger, H.; Lemarenko, M.; Lutticke, F.; Marinas, C.; Schnell, M.; Wermes, N.; Campbell, A.; Ferber, T.; Kleinwort, C.; Niebuhr, C.; Soloviev, Y.; Steder, M.; Volkenborn, R.; Yaschenko, S.; Fischer, P.; Kreidl, C.; Peric, I.; Knopf, J.; Ritzert, M.; Curras, E.; Lopez-Virto, A.; Moya, D.; Vila, I.; Boronat, M.; Esperante, D.; Fuster, J.; Garcia, I. Garcia; Lacasta, C.; Oyanguren, A.; Ruiz, P.; Timon, G.; Vos, M.; Gessler, T.; Kuhn, W.; Lange, S.; Munchow, D.; Spruck, B.; Frey, A.; Geisler, C.; Schwenker, B.; Wilk, F.; Barvich, T.; Heck, M.; Heindl, S.; Lutz, O.; Muller, Th.; Pulvermacher, C.; Simonis, H. J.; Weiler, T.; Krausser, T.; Lipsky, O.; Rummel, S.; Schieck, J.; Schluter, T.; Ackermann, K.; Andricek, L.; Chekelian, V.; Chobanova, V.; Dalseno, J.; Kiesling, C.; Koffmane, C.; Gioi, L. Li; Moll, A.; Moser, H. G.; Muller, F.; Nedelkovska, E.; Ninkovic, J.; Petrovics, S.; Prothmann, K.; Richter, R.; Ritter, A.; Ritter, M.; Simon, F.; Vanhoefer, P.; Wassatsch, A.; Dolezal, Z.; Drasal, Z.; Kodys, P.; Kvasnicka, P.; Scheirich, J.

    2013-04-01

    The DEPFET collaboration develops highly granular, ultra-transparent active pixel detectors for high-performance vertex reconstruction at future collider experiments. The characterization of detector prototypes has proven that the key principle, the integration of a first amplification stage in a detector-grade sensor material, can provide a comfortable signal to noise ratio of over 40 for a sensor thickness of 50-75 $\\mathrm{\\mathbf{\\mu m}}$. ASICs have been designed and produced to operate a DEPFET pixel detector with the required read-out speed. A complete detector concept is being developed, including solutions for mechanical support, cooling and services. In this paper the status of DEPFET R & D project is reviewed in the light of the requirements of the vertex detector at a future linear $\\mathbf{e^+ e^-}$ collider.

  17. CCD and CMOS sensors

    NASA Astrophysics Data System (ADS)

    Waltham, Nick

    The charge-coupled device (CCD) has been developed primarily as a compact image sensor for consumer and industrial markets, but is now also the preeminent visible and ultraviolet wavelength image sensor in many fields of scientific research including space-science and both Earth and planetary remote sensing. Today"s scientific or science-grade CCD will strive to maximise pixel count, focal plane coverage, photon detection efficiency over the broadest spectral range and signal dynamic range whilst maintaining the lowest possible readout noise. The relatively recent emergence of complementary metal oxide semiconductor (CMOS) image sensor technology is arguably the most important development in solid-state imaging since the invention of the CCD. CMOS technology enables the integration on a single silicon chip of a large array of photodiode pixels alongside all of the ancillary electronics needed to address the array and digitise the resulting analogue video signal. Compared to the CCD, CMOS promises a more compact, lower mass, lower power and potentially more radiation tolerant camera.

  18. X-ray characterization of CMOS imaging detector with high resolution for fluoroscopic imaging application

    NASA Astrophysics Data System (ADS)

    Cha, Bo Kyung; Kim, Cho Rong; Jeon, Seongchae; Kim, Ryun Kyung; Seo, Chang-Woo; Yang, Keedong; Heo, Duchang; Lee, Tae-Bum; Shin, Min-Seok; Kim, Jong-Boo; Kwon, Oh-Kyung

    2013-12-01

    This paper introduces complementary metal-oxide semiconductor (CMOS) active pixel sensor (APS)-based X-ray imaging detectors with high spatial resolution for medical imaging application. In this study, our proposed X-ray CMOS imaging sensor has been fabricated by using a 0.35 μm 1 Poly 4 Metal CMOS process. The pixel size is 100 μm×100 μm and the pixel array format is 24×96 pixels, which provide a field-of-view (FOV) of 9.6 mm×2.4 mm. The 14.3-bit extend counting analog-to digital converter (ADC) with built-in binning mode was used to reduce the area and simultaneously improve the image resolution. Both thallium-doped CsI (CsI:Tl) and Gd2O2S:Tb scintillator screens were used as converters for incident X-rays to visible light photons. The optical property and X-ray imaging characterization such as X-ray to light response as a function of incident X-ray exposure dose, spatial resolution and X-ray images of objects were measured under different X-ray energy conditions. The measured results suggest that our developed CMOS-based X-ray imaging detector has the potential for fluoroscopic imaging and cone-beam computed tomography (CBCT) imaging applications.

  19. CMOS/LCOS-based image transceiver device: II

    NASA Astrophysics Data System (ADS)

    Efron, Uzi; Davidov, Isak; Sinelnikov, Vladimir; Friesem, Asher A.

    2001-11-01

    A CMOS-liquid crystal-based image transceiver device (ITD) is under development at the Holon Institute of Technology. The device combines both functions of imaging and display in a single array configuration. This unique structure allows the combination of see-through, aiming, imaging and the displaying of a superposed image to be combined in a single, compact, head mounted display. The CMOS-based pixel elements are designed to provide efficient imaging in the visible range as well as driver capabilities for the overlying liquid crystal modulator. The image sensor part of the pixel is based on an n-well photodiode and a three-transistor readout circuit. The imaging function is based on a back- illuminated sensor configuration. In order to provide a high imager fill-factor, two pixel configurations are proposed: 1) A p++/p-/p-well silicon structure using twin- well CMOS process; 2) An n-well processed silicon structure with a micro-lens array. The display portion of the IT device is to be fabricated on a silicon-based reflective, active matrix driver, using nematic liquid crystal material, in LCOS technology. The timing, sequencing and control of the IT device array are designed in a pipeline array processing scheme. A preliminary prototype system and device design have been performed and the first test device is currently undergoing testing. Details of the device design as well as its Smart Goggle applications are presented.

  20. Comparative study of various pixel photodiodes for digital radiography: Junction structure, corner shape and noble window opening

    NASA Astrophysics Data System (ADS)

    Kang, Dong-Uk; Cho, Minsik; Lee, Dae Hee; Yoo, Hyunjun; Kim, Myung Soo; Bae, Jun Hyung; Kim, Hyoungtaek; Kim, Jongyul; Kim, Hyunduk; Cho, Gyuseong

    2012-05-01

    Recently, large-size 3-transistors (3-Tr) active pixel complementary metal-oxide silicon (CMOS) image sensors have been being used for medium-size digital X-ray radiography, such as dental computed tomography (CT), mammography and nondestructive testing (NDT) for consumer products. We designed and fabricated 50 µm × 50 µm 3-Tr test pixels having a pixel photodiode with various structures and shapes by using the TSMC 0.25-m standard CMOS process to compare their optical characteristics. The pixel photodiode output was continuously sampled while a test pixel was continuously illuminated by using 550-nm light at a constant intensity. The measurement was repeated 300 times for each test pixel to obtain reliable results on the mean and the variance of the pixel output at each sampling time. The sampling rate was 50 kHz, and the reset period was 200 msec. To estimate the conversion gain, we used the mean-variance method. From the measured results, the n-well/p-substrate photodiode, among 3 photodiode structures available in a standard CMOS process, showed the best performance at a low illumination equivalent to the typical X-ray signal range. The quantum efficiencies of the n+/p-well, n-well/p-substrate, and n+/p-substrate photodiodes were 18.5%, 62.1%, and 51.5%, respectively. From a comparison of pixels with rounded and rectangular corners, we found that a rounded corner structure could reduce the dark current in large-size pixels. A pixel with four rounded corners showed a reduced dark current of about 200fA compared to a pixel with four rectangular corners in our pixel sample size. Photodiodes with round p-implant openings showed about 5% higher dark current, but about 34% higher sensitivities, than the conventional photodiodes.

  1. Towards using a Monolithic Active Pixel Sensor for in vivo beam monitoring of Intensity Modulated Radiotherapy

    NASA Astrophysics Data System (ADS)

    Page, R. F.; Abbott, N. L.; Davies, J.; Dyke, E. L.; Randles, H. J.; Velthuis, J. J.; Fletcher, S.; Gregory, S. D.; Hall, C.; John, A.; Lawrence, H.; Stevens, P. H.; Hugtenburg, R. P.; Tunbridge, V.

    2013-12-01

    The use of Intensity Modulated Radiotherapy (IMRT) for cancer treatments is entering wider use. These treatments involve using a complex configuration of field modifying components, known as Multileaf Collimators (MLC), to dynamically shape the beam. A treatment consists of a sequence of irregular shaped fields, which means real time monitoring and verification is essential. In the current framework the treatment plans are verified before the patient is treated, but not during. The aim of our collaboration is to monitor the treatment being given to the patient. This is achieved by placing a camera system using an ultra-thin Monolithic Active Pixel Sensor (MAPS) upstream of the patient.

  2. Smart-Pixel Array Processors Based on Optimal Cellular Neural Networks for Space Sensor Applications

    NASA Technical Reports Server (NTRS)

    Fang, Wai-Chi; Sheu, Bing J.; Venus, Holger; Sandau, Rainer

    1997-01-01

    A smart-pixel cellular neural network (CNN) with hardware annealing capability, digitally programmable synaptic weights, and multisensor parallel interface has been under development for advanced space sensor applications. The smart-pixel CNN architecture is a programmable multi-dimensional array of optoelectronic neurons which are locally connected with their local neurons and associated active-pixel sensors. Integration of the neuroprocessor in each processor node of a scalable multiprocessor system offers orders-of-magnitude computing performance enhancements for on-board real-time intelligent multisensor processing and control tasks of advanced small satellites. The smart-pixel CNN operation theory, architecture, design and implementation, and system applications are investigated in detail. The VLSI (Very Large Scale Integration) implementation feasibility was illustrated by a prototype smart-pixel 5x5 neuroprocessor array chip of active dimensions 1380 micron x 746 micron in a 2-micron CMOS technology.

  3. Measurements on HV-CMOS active sensors after irradiation to HL-LHC fluences

    NASA Astrophysics Data System (ADS)

    Ristic, B.

    2015-04-01

    During the long shutdown (LS) 3 beginning 2022 the LHC will be upgraded for higher luminosities pushing the limits especially for the inner tracking detectors of the LHC experiments. In order to cope with the increased particle rate and radiation levels the ATLAS Inner Detector will be completely replaced by a purely silicon based one. Novel sensors based on HV-CMOS processes prove to be good candidates in terms of spatial resolution and radiation hardness. In this paper measurements conducted on prototypes built in the AMS H18 HV-CMOS process and irradiated to fluences of up to 2·1016 neq cm-2 are presented.

  4. TFT-Based Active Pixel Sensors for Large Area Thermal Neutron Detection

    NASA Astrophysics Data System (ADS)

    Kunnen, George

    Due to diminishing availability of 3He, which is the critical component of neutron detecting proportional counters, large area flexible arrays are being considered as a potential replacement for neutron detection. A large area flexible array, utilizing semiconductors for both charged particle detection and pixel readout, ensures a large detection surface area in a light weight rugged form. Such a neutron detector could be suitable for deployment at ports of entry. The specific approach used in this research, uses a neutron converter layer which captures incident thermal neutrons, and then emits ionizing charged particles. These ionizing particles cause electron-hole pair generation within a single pixel's integrated sensing diode. The resulting charge is then amplified via a low-noise amplifier. This document begins by discussing the current state of the art in neutron detection and the associated challenges. Then, for the purpose of resolving some of these issues, recent design and modeling efforts towards developing an improved neutron detection system are described. Also presented is a low-noise active pixel sensor (APS) design capable of being implemented in low temperature indium gallium zinc oxide (InGaZnO) or amorphous silicon (a-Si:H) thin film transistor process compatible with plastic substrates. The low gain and limited scalability of this design are improved upon by implementing a new multi-stage self-resetting APS. For each APS design, successful radiation measurements are also presented using PiN diodes for charged particle detection. Next, detection array readout methodologies are modeled and analyzed, and use of a matched filter readout circuit is described as well. Finally, this document discusses detection diode integration with the designed TFT-based APSs.

  5. Low noise signal-to-noise ratio enhancing readout circuit for current-mediated active pixel sensors

    SciTech Connect

    Ottaviani, Tony; Karim, Karim S.; Nathan, Arokia; Rowlands, John A.

    2006-05-15

    Diagnostic digital fluoroscopic applications continuously expose patients to low doses of x-ray radiation, posing a challenge to both the digital imaging pixel and readout electronics when amplifying small signal x-ray inputs. Traditional switch-based amorphous silicon imaging solutions, for instance, have produced poor signal-to-noise ratios (SNRs) at low exposure levels owing to noise sources from the pixel readout circuitry. Current-mediated amorphous silicon pixels are an improvement over conventional pixel amplifiers with an enhanced SNR across the same low-exposure range, but whose output also becomes nonlinear with increasing dosage. A low-noise SNR enhancing readout circuit has been developed that enhances the charge gain of the current-mediated active pixel sensor (C-APS). The solution takes advantage of the current-mediated approach, primarily integrating the signal input at the desired frequency necessary for large-area imaging, while adding minimal noise to the signal readout. Experimental data indicates that the readout circuit can detect pixel outputs over a large bandwidth suitable for real-time digital diagnostic x-ray fluoroscopy. Results from hardware testing indicate that the minimum achievable C-APS output current that can be discerned at the digital fluoroscopic output from the enhanced SNR readout circuit is 0.341 nA. The results serve to highlight the applicability of amorphous silicon current-mediated pixel amplifiers for large-area flat panel x-ray imagers.

  6. Low-cost uncooled infrared detector arrays in standard CMOS

    NASA Astrophysics Data System (ADS)

    Eminoglu, Selim; Tanrikulu, M. Y.; Akin, Tayfun

    2003-09-01

    This paper reports the development of a low-cost 128 x 128 uncooled infrared focal plane array (FPA) based on suspended and thermally isolated CMOS p+-active/n-well diodes. The FPA is fabricated using a standard 0.35 μm CMOS process followed by simple post-CMOS bulk micromachining that does not require any critical lithography or complicated deposition steps; and therefore, the cost of the uncooled FPA is almost equal to the cost of the CMOS chip. The post-CMOS fabrication steps include an RIE etching to reach the bulk silicon and an anisotropic silicon etching to obtain thermally isolated pixels. During the RIE etching, CMOS metal layers are used as masking layers, and therefore, narrow openings such as 2 μm can be defined between the support arms. This approach allows achieving small pixel size of 40 μm x 40 μm with a fill factor of 44%. The FPA is scanned at 30 fps by monolithically integrated multi-channel parallel readout circuitry which is composed of low-noise differential transconductance amplifiers, switched capacitor (SC) integrators, sample-and-hold circuits, and various other circuit blocks for reducing the effects of variations in detector voltage and operating temperature. The fabricated detector has a temperature coefficient of -2 mV/K, a thermal conductance value of 1.8 x 10-7 W/K, and a thermal time constant value of 36 msec, providing a measured DC responsivity (R) of 4970 V/W under continuous bias. Measured detector noise is 0.69 μV in 8 kHz bandwidth at 30 fps scanning rate, resulting a measured detectivity (D*) of 9.7 x 108 cm√HzW. Contribution of the 1/f noise component is found to be negligible due to the single crystal nature of the silicon n-well and its low value at low bias levels. The noise of the readout circuit is measured as 0.76 μV, resulting in an expected NETD value of 1 K when scanned at 30 fps using f=1 optics. This NETD value can be decreased below 350 mK by decreasing the electrical bandwidth with the help of increased

  7. Direct tests of a pixelated microchannel plate as the active element of a shower maximum detector

    DOE PAGESBeta

    Apresyan, A.; Los, S.; Pena, C.; Presutti, F.; Ronzhin, A.; Spiropulu, M.; Xie, S.

    2016-05-07

    One possibility to make a fast and radiation resistant shower maximum detector is to use a secondary emitter as an active element. We report our studies of microchannel plate photomultipliers (MCPs) as the active element of a shower-maximum detector. We present test beam results obtained using Photonis XP85011 to detect secondary particles of an electromagnetic shower. We focus on the use of the multiple pixels on the Photonis MCP in order to find a transverse two-dimensional shower distribution. A spatial resolution of 0.8 mm was obtained with an 8 GeV electron beam. As a result, a method for measuring themore » arrival time resolution for electromagnetic showers is presented, and we show that time resolution better than 40 ps can be achieved.« less

  8. Direct tests of a pixelated microchannel plate as the active element of a shower maximum detector

    NASA Astrophysics Data System (ADS)

    Apresyan, A.; Los, S.; Pena, C.; Presutti, F.; Ronzhin, A.; Spiropulu, M.; Xie, S.

    2016-08-01

    One possibility to make a fast and radiation resistant shower maximum detector is to use a secondary emitter as an active element. We report our studies of microchannel plate photomultipliers (MCPs) as the active element of a shower-maximum detector. We present test beam results obtained using Photonis XP85011 to detect secondary particles of an electromagnetic shower. We focus on the use of the multiple pixels on the Photonis MCP in order to find a transverse two-dimensional shower distribution. A spatial resolution of 0.8 mm was obtained with an 8 GeV electron beam. A method for measuring the arrival time resolution for electromagnetic showers is presented, and we show that time resolution better than 40 ps can be achieved.

  9. Silicon-on-insulator (SOI) active pixel sensors with the photosite implemented in the substrate

    NASA Technical Reports Server (NTRS)

    Zheng, Xinyu (Inventor); Pain, Bedabrata (Inventor)

    2005-01-01

    Active pixel sensors for a high quality imager are fabricated using a silicon-on-insulator (SOI) process by integrating the photodetectors on the SOI substrate and forming pixel readout transistors on the SOI thin-film. The technique can include forming silicon islands on a buried insulator layer disposed on a silicon substrate and selectively etching away the buried insulator layer over a region of the substrate to define a photodetector area. Dopants of a first conductivity type are implanted to form a signal node in the photodetector area and to form simultaneously drain/source regions for a first transistor in at least a first one of the silicon islands. Dopants of a second conductivity type are implanted to form drain/source regions for a second transistor in at least a second one of the silicon islands. Isolation rings around the photodetector also can be formed when dopants of the second conductivity type are implanted. Interconnections among the transistors and the photodetector are provided to allow signals sensed by the photodetector to be read out via the transistors formed on the silicon islands.

  10. Silicon-on-insulator (SOI) active pixel sensors with the photosite implemented in the substrate

    NASA Technical Reports Server (NTRS)

    Pain, Bedabrata (Inventor); Zheng, Xinyu (Inventor)

    2002-01-01

    Active pixel sensors for a high quality imager are fabricated using a silicon-on-insulator (SOI) process by integrating the photodetectors on the SOI substrate and forming pixel readout transistors on the SOI thin-film. The technique can include forming silicon islands on a buried insulator layer disposed on a silicon substrate and selectively etching away the buried insulator layer over a region of the substrate to define a photodetector area. Dopants of a first conductivity type are implanted to form a signal node in the photodetector area and to form simultaneously drain/source regions for a first transistor in at least a first one of the silicon islands. Dopants of a second conductivity type are implanted to form drain/source regions for a second transistor in at least a second one of the silicon islands. Isolation rings around the photodetector also can be formed when dopants of the second conductivity type are implanted. Interconnections among the transistors and the photodetector are provided to allow signals sensed by the photodetector to be read out via the transistors formed on the silicon islands.

  11. CMOS focal-plane-array for analysis of enzymatic reaction in system-on-chip spectrophotometer

    NASA Astrophysics Data System (ADS)

    Wang, Dong; Ha, Chanki; Park, Chan B.; Joo, Youngjoong

    2004-06-01

    A CMOS focal-plane-array is designed for the high-throughput analysis of enzymatic reaction in on-chip spectrophotometer system. One of potential applications of the presented prototype system is to perform enzymatic analysis of biocompounds contained in blood. This function normally requires an expensive diode-array spectrophotometer, but it is possible to perform high throughput analysis with low budget if the spectrophotometer system is scaled down to a chip. The CMOS active pixel sensor array can cover a layer of polydimethylsiloxane (PDMS) forming the microfluidic channels and the substrate solution for enzymatic reaction can be injected into the channels by capillary force. Under room light, the underneath CMOS active pixel sensor with 40 x 40 pixels detect the gray levels of the fluid"s color. Inside the image sensor chip (size: 3mm x 3mm), the pixels of the same column share the same sample and hold circuits. The analog signals from 40 columns are multiplexed into one input feeding an on-chip 8 bits dual-slope analog to digital converter. The color change can be displayed on the external monitor by using a data acquisition card and personal computer.

  12. Planar CMOS analog SiPMs: design, modeling, and characterization

    NASA Astrophysics Data System (ADS)

    Zou, Yu; Villa, Federica; Bronzi, Danilo; Tisa, Simone; Tosi, Alberto; Zappa, Franco

    2015-11-01

    Silicon photomultipliers (SiPMs) are large area detectors consisting of an array of single-photon-sensitive microcells, which make SiPMs extremely attractive to substitute the photomultiplier tubes in many applications. We present the design, fabrication, and characterization of analog SiPMs in standard planar 0.35 μm CMOS technology, with about 1 mm × 1 mm total area and different kinds of microcells, based on single-photon avalanche diodes with 30 μm diameter reaching 21.0% fill-factor (FF), 50 μm diameter (FF = 58.3%) or 50 μm square active area with rounded corner of 5 μm radius (FF = 73.7%). We also developed the electrical SPICE model for CMOS SiPMs. Our CMOS SiPMs have 25 V breakdown voltage, in line with most commercial SiPMs and higher gain (8.8 × 106, 13.2 × 106, and 15.0 × 106, respectively). Although dark count rate density is slightly higher than state-of-the-art analog SiPMs, the proposed standard CMOS processing opens the feasibility of integration with active electronics, for switching hot pixels off, drastically reducing the overall dark count rate, or for further on-chip processing.

  13. A high frequency active voltage doubler in standard CMOS using offset-controlled comparators for inductive power transmission.

    PubMed

    Lee, Hyung-Min; Ghovanloo, Maysam

    2013-06-01

    In this paper, we present a fully integrated active voltage doubler in CMOS technology using offset-controlled high speed comparators for extending the range of inductive power transmission to implantable microelectronic devices (IMD) and radio-frequency identification (RFID) tags. This active voltage doubler provides considerably higher power conversion efficiency (PCE) and lower dropout voltage compared to its passive counterpart and requires lower input voltage than active rectifiers, leading to reliable and efficient operation with weakly coupled inductive links. The offset-controlled functions in the comparators compensate for turn-on and turn-off delays to not only maximize the forward charging current to the load but also minimize the back current, optimizing PCE in the high frequency (HF) band. We fabricated the active voltage doubler in a 0.5-μm 3M2P std . CMOS process, occupying 0.144 mm(2) of chip area. With 1.46 V peak AC input at 13.56 MHz, the active voltage doubler provides 2.4 V DC output across a 1 kΩ load, achieving the highest PCE = 79% ever reported at this frequency. In addition, the built-in start-up circuit ensures a reliable operation at lower voltages. PMID:23853321

  14. A High Frequency Active Voltage Doubler in Standard CMOS Using Offset-Controlled Comparators for Inductive Power Transmission

    PubMed Central

    Lee, Hyung-Min; Ghovanloo, Maysam

    2014-01-01

    In this paper, we present a fully integrated active voltage doubler in CMOS technology using offset-controlled high speed comparators for extending the range of inductive power transmission to implantable microelectronic devices (IMD) and radio-frequency identification (RFID) tags. This active voltage doubler provides considerably higher power conversion efficiency (PCE) and lower dropout voltage compared to its passive counterpart and requires lower input voltage than active rectifiers, leading to reliable and efficient operation with weakly coupled inductive links. The offset-controlled functions in the comparators compensate for turn-on and turn-off delays to not only maximize the forward charging current to the load but also minimize the back current, optimizing PCE in the high frequency (HF) band. We fabricated the active voltage doubler in a 0.5-μm 3M2P std. CMOS process, occupying 0.144 mm2 of chip area. With 1.46 V peak AC input at 13.56 MHz, the active voltage doubler provides 2.4 V DC output across a 1 kΩ load, achieving the highest PCE = 79% ever reported at this frequency. In addition, the built-in start-up circuit ensures a reliable operation at lower voltages. PMID:23853321

  15. SOI CMOS Imager with Suppression of Cross-Talk

    NASA Technical Reports Server (NTRS)

    Pain, Bedabrata; Zheng, Xingyu; Cunningham, Thomas J.; Seshadri, Suresh; Sun, Chao

    2009-01-01

    A monolithic silicon-on-insulator (SOI) complementary metal oxide/semiconductor (CMOS) image-detecting integrated circuit of the active-pixel-sensor type, now undergoing development, is designed to operate at visible and near-infrared wavelengths and to offer a combination of high quantum efficiency and low diffusion and capacitive cross-talk among pixels. The imager is designed to be especially suitable for astronomical and astrophysical applications. The imager design could also readily be adapted to general scientific, biological, medical, and spectroscopic applications. One of the conditions needed to ensure both high quantum efficiency and low diffusion cross-talk is a relatively high reverse bias potential (between about 20 and about 50 V) on the photodiode in each pixel. Heretofore, a major obstacle to realization of this condition in a monolithic integrated circuit has been posed by the fact that the required high reverse bias on the photodiode is incompatible with metal oxide/semiconductor field-effect transistors (MOSFETs) in the CMOS pixel readout circuitry. In the imager now being developed, the SOI structure is utilized to overcome this obstacle: The handle wafer is retained and the photodiode is formed in the handle wafer. The MOSFETs are formed on the SOI layer, which is separated from the handle wafer by a buried oxide layer. The electrical isolation provided by the buried oxide layer makes it possible to bias the MOSFETs at CMOS-compatible potentials (between 0 and 3 V), while biasing the photodiode at the required higher potential, and enables independent optimization of the sensory and readout portions of the imager.

  16. Intelligent error correction method applied on an active pixel sensor based star tracker

    NASA Astrophysics Data System (ADS)

    Schmidt, Uwe

    2005-10-01

    Star trackers are opto-electronic sensors used on-board of satellites for the autonomous inertial attitude determination. During the last years star trackers became more and more important in the field of the attitude and orbit control system (AOCS) sensors. High performance star trackers are based up today on charge coupled device (CCD) optical camera heads. The active pixel sensor (APS) technology, introduced in the early 90-ties, allows now the beneficial replacement of CCD detectors by APS detectors with respect to performance, reliability, power, mass and cost. The company's heritage in star tracker design started in the early 80-ties with the launch of the worldwide first fully autonomous star tracker system ASTRO1 to the Russian MIR space station. Jena-Optronik recently developed an active pixel sensor based autonomous star tracker "ASTRO APS" as successor of the CCD based star tracker product series ASTRO1, ASTRO5, ASTRO10 and ASTRO15. Key features of the APS detector technology are, a true xy-address random access, the multiple windowing read out and the on-chip signal processing including the analogue to digital conversion. These features can be used for robust star tracking at high slew rates and under worse conditions like stray light and solar flare induced single event upsets. A special algorithm have been developed to manage the typical APS detector error contributors like fixed pattern noise (FPN), dark signal non-uniformity (DSNU) and white spots. The algorithm works fully autonomous and adapts to e.g. increasing DSNU and up-coming white spots automatically without ground maintenance or re-calibration. In contrast to conventional correction methods the described algorithm does not need calibration data memory like full image sized calibration data sets. The application of the presented algorithm managing the typical APS detector error contributors is a key element for the design of star trackers for long term satellite applications like

  17. Design of a silicon avalanche photodiode pixel with integrated laser diode using back-illuminated crystallographically etched silicon-on-sapphire with monolithically integrated microlens for dual-mode passive and active imaging arrays

    NASA Astrophysics Data System (ADS)

    Stern, Alvin G.

    2010-08-01

    There is a growing need in scientific research applications for dual-mode, passive and active 2D and 3D LADAR imaging methods. To fill this need, an advanced back-illuminated silicon avalanche photodiode (APD) design is presented using a novel silicon-on-sapphire substrate incorporating a crystalline aluminum nitride (AlN) antireflective layer between the silicon and R-plane sapphire. This allows integration of a high quantum efficiency silicon APD with a gallium nitride (GaN) laser diode in each pixel. The pixel design enables single photon sensitive, solid-state focal plane arrays (FPAs) with wide dynamic range, supporting passive and active imaging capability in a single FPA. When (100) silicon is properly etched with TMAH solution, square based pyramidal frustum or mesa arrays result with the four mesa sidewalls of the APD formed by (111) silicon planes that intersect the (100) planes at a crystallographic angle, φ c = 54.7°. The APD device is fabricated in the mesa using conventional silicon processing technology. The GaN laser diode is fabricated by epitaxial growth inside of an inverted, etched cavity in the silicon mesa. Microlenses are fabricated in the thinned, and AR-coated sapphire substrate. The APDs share a common, front-side anode contact, and laser diodes share a common cathode. A low resistance (Al) or (Cu) metal anode grid fills the space between pixels and also inhibits optical crosstalk. SOS-APD arrays are flip-chip bump-bonded to CMOS readout ICs to produce hybrid FPAs. The square 27 μm emitter-detector pixel achieves SNR > 1 in active detection mode for Lambert surfaces at 1,000 meters.

  18. Nanosecond monolithic CMOS readout cell

    DOEpatents

    Souchkov, Vitali V.

    2004-08-24

    A pulse shaper is implemented in monolithic CMOS with a delay unit formed of a unity gain buffer. The shaper is formed of a difference amplifier having one input connected directly to an input signal and a second input connected to a delayed input signal through the buffer. An elementary cell is based on the pulse shaper and a timing circuit which gates the output of an integrator connected to the pulse shaper output. A detector readout system is formed of a plurality of elementary cells, each connected to a pixel of a pixel array, or to a microstrip of a plurality of microstrips, or to a detector segment.

  19. Improved Space Object Orbit Determination Using CMOS Detectors

    NASA Astrophysics Data System (ADS)

    Schildknecht, T.; Peltonen, J.; Sännti, T.; Silha, J.; Flohrer, T.

    2014-09-01

    CMOS-sensors, or in general Active Pixel Sensors (APS), are rapidly replacing CCDs in the consumer camera market. Due to significant technological advances during the past years these devices start to compete with CCDs also for demanding scientific imaging applications, in particular in the astronomy community. CMOS detectors offer a series of inherent advantages compared to CCDs, due to the structure of their basic pixel cells, which each contains their own amplifier and readout electronics. The most prominent advantages for space object observations are the extremely fast and flexible readout capabilities, feasibility for electronic shuttering and precise epoch registration, and the potential to perform image processing operations on-chip and in real-time. The major challenges and design drivers for ground-based and space-based optical observation strategies have been analyzed. CMOS detector characteristics were critically evaluated and compared with the established CCD technology, especially with respect to the above mentioned observations. Similarly, the desirable on-chip processing functionalities which would further enhance the object detection and image segmentation were identified. Finally, we simulated several observation scenarios for ground- and space-based sensor by assuming different observation and sensor properties. We will introduce the analyzed end-to-end simulations of the ground- and space-based strategies in order to investigate the orbit determination accuracy and its sensitivity which may result from different values for the frame-rate, pixel scale, astrometric and epoch registration accuracies. Two cases were simulated, a survey using a ground-based sensor to observe objects in LEO for surveillance applications, and a statistical survey with a space-based sensor orbiting in LEO observing small-size debris in LEO. The ground-based LEO survey uses a dynamical fence close to the Earth shadow a few hours after sunset. For the space-based scenario

  20. Accelerated life testing effects on CMOS microcircuit characteristics

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Accelerated life tests were performed on CMOS microcircuits to predict their long term reliability. The consistency of the CMOS microcircuit activation energy between the range of 125 C to 200 C and the range 200 C to 250 C was determined. Results indicate CMOS complexity and the amount of moisture detected inside the devices after testing influences time to failure of tested CMOS devices.

  1. Characterization of Si Hybrid CMOS Detectors for use in the Soft X-ray Band

    NASA Astrophysics Data System (ADS)

    Prieskorn, Zachary; Griffith, C.; Bongiorno, S.; Falcone, A.; Burrows, D. N.

    2014-01-01

    In a joint program between Penn State University and Teledyne Imaging Sensors a soft X-ray detector based on the HAWAII Hybrid Si CMOS detector (HCD) has been developed. HCDs could potentially be the optimum detectors for the next generation of X-ray missions, especially those with focused optics and/or large effective area. These innovative detectors are active pixel sensors (APS) which allow a pixel to be read through individual in-pixel electronics, without the need to transfer charge across many pixels, in contrast to a CCD. They are made by bonding a Si absorbing layer to a pixelated CMOS readout, allowing the two layers to be optimized independently. The advantages of this design compared to CCDs are high speed timing 100 μs in full imaging mode), a flexible windowed readout to reduce pile-up, dramatically improved radiation hardness and resistance to micrometeoroid damage, and reduced power requirements. We present recent measurements of energy resolution, read noise, inter-pixel crosstalk, quantum efficiency, and dark current for four of these devices.

  2. High-voltage pixel sensors for ATLAS upgrade

    NASA Astrophysics Data System (ADS)

    Perić, I.; Kreidl, C.; Fischer, P.; Bompard, F.; Breugnon, P.; Clemens, J.-C.; Fougeron, D.; Liu, J.; Pangaud, P.; Rozanov, A.; Barbero, M.; Feigl, S.; Capeans, M.; Ferrere, D.; Pernegger, H.; Ristic, B.; Muenstermann, D.; Gonzalez Sevilla, S.; La Rosa, A.; Miucci, A.; Nessi, M.; Iacobucci, G.; Backhaus, M.; Hügging, Fabian; Krüger, H.; Hemperek, T.; Obermann, T.; Wermes, N.; Garcia-Sciveres, M.; Quadt, A.; Weingarten, J.; George, M.; Grosse-Knetter, J.; Rieger, J.; Bates, R.; Blue, A.; Buttar, C.; Hynds, D.

    2014-11-01

    The high-voltage (HV-) CMOS pixel sensors offer several good properties: a fast charge collection by drift, the possibility to implement relatively complex CMOS in-pixel electronics and the compatibility with commercial processes. The sensor element is a deep n-well diode in a p-type substrate. The n-well contains CMOS pixel electronics. The main charge collection mechanism is drift in a shallow, high field region, which leads to a fast charge collection and a high radiation tolerance. We are currently evaluating the use of the high-voltage detectors implemented in 180 nm HV-CMOS technology for the high-luminosity ATLAS upgrade. Our approach is replacing the existing pixel and strip sensors with the CMOS sensors while keeping the presently used readout ASICs. By intelligence we mean the ability of the sensor to recognize a particle hit and generate the address information. In this way we could benefit from the advantages of the HV sensor technology such as lower cost, lower mass, lower operating voltage, smaller pitch, smaller clusters at high incidence angles. Additionally we expect to achieve a radiation hardness necessary for ATLAS upgrade. In order to test the concept, we have designed two HV-CMOS prototypes that can be readout in two ways: using pixel and strip readout chips. In the case of the pixel readout, the connection between HV-CMOS sensor and the readout ASIC can be established capacitively.

  3. First light from a very large area pixel array for high-throughput x-ray polarimetry

    NASA Astrophysics Data System (ADS)

    Bellazzini, R.; Spandre, G.; Minuti, M.; Baldini, L.; Brez, A.; Cavalca, F.; Latronico, L.; Omodei, N.; Massai, M. M.; Sgrò, C.; Costa, E.; Soffitta, P.; Krummenacher, F.; de Oliveira, R.

    2006-06-01

    We report on a large active area (15x15mm2), high channel density (470 pixels/mm2), self-triggering CMOS analog chip that we have developed as pixelized charge collecting electrode of a Micropattern Gas Detector. This device, which represents a big step forward both in terms of size and performance, is the last version of three generations of custom ASICs of increasing complexity. The CMOS pixel array has the top metal layer patterned in a matrix of 105600 hexagonal pixels at 50μm pitch. Each pixel is directly connected to the underneath full electronics chain which has been realized in the remaining five metal and single poly-silicon layers of a standard 0.18μm CMOS VLSI technology. The chip has customizable self-triggering capability and includes a signal pre-processing function for the automatic localization of the event coordinates. In this way it is possible to reduce significantly the readout time and the data volume by limiting the signal output only to those pixels belonging to the region of interest. The very small pixel area and the use of a deep sub-micron CMOS technology has brought the noise down to 50 electrons ENC. Results from in depth tests of this device when coupled to a fine pitch (50μm on a triangular pattern) Gas Electron Multiplier are presented. The matching of readout and gas amplification pitch allows getting optimal results. The application of this detector for Astronomical X-Ray Polarimetry is discussed. The experimental detector response to polarized and unpolarized X-ray radiation when working with two gas mixtures and two different photon energies is shown. Results from a full MonteCarlo simulation for several galactic and extragalactic astronomical sources are also reported.

  4. A new CMOS-based digital imaging detector for applications in mammography

    NASA Astrophysics Data System (ADS)

    Baysal, Mehmet A.; Toker, Emre

    2005-09-01

    We have developed a CMOS-based x-ray imaging detector in the same form factor of a standard film cassette (18 cm × 24 cm) for Small Field-of-view Digital Mammography (SFDM) applications. This SFDM cassette is based on our three-side buttable, 25 mm × 50 mm, 48μm active-pixel CMOS sensor modules and utilizes a 150μm columnar CsI(Tl) scintillator. For imaging up to 100 mm × 100 mm field-of-view, a number of CMOS sensor modules need to be tiled and electronically synchronized together. By using fiber-optic communication, acquired images from the SFDM cassette can be transferred, processed and displayed on a review station within approximately 5 seconds of exposure, greatly enhancing patient flow. We present the physical performance of this CMOS-based SFDM cassette, using established objective criteria such as the Modulation Transfer Function (MTF), Detective Quantum Efficiency (DQE), and more subjective criteria, by evaluating images from a phantom study and the clinical studies of our collaborators. Driven by the strong demand from the computer industry, CMOS technology is one of the lowest cost, and the most readily accessible technologies available for digital mammography today. Recent popular use of CMOS imagers in high-end consumer cameras have also resulted in significant advances in the imaging performance of CMOS sensors against rivaling CCD sensors. The SFDM cassette can be employed in various mammography applications, including spot imaging, stereotactic biopsy imaging, core biopsy and surgical biopsy specimen radiography. This study demonstrates that all the image quality requirements for demanding mammography applications can be addressed with CMOS technology.

  5. CMOS image sensor integrated with micro-LED and multielectrode arrays for the patterned photostimulation and multichannel recording of neuronal tissue.

    PubMed

    Nakajima, Arata; Kimura, Hiroshi; Sawadsaringkarn, Yosmongkol; Maezawa, Yasuyo; Kobayashi, Takuma; Noda, Toshihiko; Sasagawa, Kiyotaka; Tokuda, Takashi; Ishikawa, Yasuyuki; Shiosaka, Sadao; Ohta, Jun

    2012-03-12

    We developed a complementary metal oxide semiconductor (CMOS) integrated device for optogenetic applications. This device can interface via neuronal tissue with three functional modalities: imaging, optical stimulation and electrical recording. The CMOS image sensor was fabricated on 0.35 μm standard CMOS process with built-in control circuits for an on-chip blue light-emitting diode (LED) array. The effective imaging area was 2.0 × 1.8 mm². The pixel array was composed of 7.5 × 7.5 μm² 3-transistor active pixel sensors (APSs). The LED array had 10 × 8 micro-LEDs measuring 192 × 225 μm². We integrated the device with a commercial multichannel recording system to make electrical recordings. PMID:22418489

  6. Simulation of active-edge pixelated CdTe radiation detectors

    NASA Astrophysics Data System (ADS)

    Duarte, D. D.; Lipp, J. D.; Schneider, A.; Seller, P.; Veale, M. C.; Wilson, M. D.; Baker, M. A.; Sellin, P. J.

    2016-01-01

    The edge surfaces of single crystal CdTe play an important role in the electronic properties and performance of this material as an X-ray and γ-ray radiation detector. Edge effects have previously been reported to reduce the spectroscopic performance of the edge pixels in pixelated CdTe radiation detectors without guard bands. A novel Technology Computer Aided Design (TCAD) model based on experimental data has been developed to investigate these effects. The results presented in this paper show how localized low resistivity surfaces modify the internal electric field of CdTe creating potential wells. These result in a reduction of charge collection efficiency of the edge pixels, which compares well with experimental data.

  7. X-RAY ACTIVE MATRIX PIXEL SENSORS BASEDON J-FET TECHNOLOGY DEVELOPED FOR THE LINAC COHERENT LIGHT SOURCE.

    SciTech Connect

    CARINI,G.A.; CHEN, W.; LI, Z.; REHAK, P.; SIDDONS, D.P.

    2007-10-29

    An X-ray Active Matrix Pixel Sensor (XAMPS) is being developed for recording data for the X-ray Pump Probe experiment at the Linac Coherent Light Source (LCLS). Special attention has to be paid to some technological challenges that this design presents. New processes were developed and refined to address problems encountered during previous productions of XAMPS. The development of these critical steps and corresponding tests results are reported here.

  8. Measurements of Si hybrid CMOS x-ray detector characteristics

    NASA Astrophysics Data System (ADS)

    Bongiorno, Stephen D.; Falcone, Abraham D.; Burrows, David N.; Cook, Robert

    2010-07-01

    The recent development of active pixel sensors as X-Ray focal plane arrays will place them in contention with CCDs on future satellite missions. Penn State University (PSU) is working with Teledyne Imaging Sensors (TIS) to develop X-Ray Hybrid CMOS devices (HCDs), a type of active pixel sensor with fast frame rates, adaptable readout timing and geometry, low power consumption, and inherent radiation hardness. CCDs have been used with great success on the current generation of X-Ray telescopes (e.g. Chandra, XMM, Suzaku, and Swift). However, their bucket-brigade readout architecture, which transfers charge across the chip with discrete component readout electronics, results in clockrate limited readout speeds that cause pileup (saturation) of bright sources and an inherent susceptibility to radiation induced displacement damage that limits mission lifetime. In contrast, HCDs read pixels through the detector substrate with low power, on-chip readout integrated circuits. Faster frame rates, achieved with adaptable readout timing and geometry, will allow the next generation's larger effective area telescopes to observe brighter sources free of pileup. In HCDs, radiation damaged lattice sites affect a single pixel instead of an entire row. The PSU X-ray group is currently testing 4 Teledyne HCDs, with low cross-talk CTIA devices in development. We will report laboratory measurements of HCD readnoise, interpixel-capacitance and its impact on event selection, linearity, and energy resolution as a function of energy.

  9. Measurement results of DIPIX pixel sensor developed in SOI technology

    NASA Astrophysics Data System (ADS)

    Ahmed, Mohammed Imran; Arai, Yasuo; Idzik, Marek; Kapusta, Piotr; Miyoshi, Toshinobu; Turala, Michal

    2013-08-01

    The development of integration type pixel detectors presents interest for physics communities because it brings optimization of design, simplicity of production-which means smaller cost, and reduction of detector material budget. During the last decade a lot of research and development activities took place in the field of CMOS Silicon-On-Insulator (SOI) technology resulting in improvement in wafer size, wafer resistivity and MIM capacitance. Several ideas have been tested successfully and are gradually entering into the application phase. Some of the novel concepts exploring SOI technology are pursued at KEK; several prototypes of dual mode integration type pixel (DIPIX) have been recently produced and described. This report presents initial test results of some of the prototypes including tests obtained with the infrared laser beams and Americium (Am-241) source. The Equivalent Noise Charge (ENC) of 86 e - has been measured. The measured performance demonstrates that SOI technology is a feasible choice for future applications.

  10. Thin n-in-p planar pixel sensors and active edge sensors for the ATLAS upgrade at HL-LHC

    NASA Astrophysics Data System (ADS)

    Terzo, S.; Macchiolo, A.; Nisius, R.; Paschen, B.

    2014-12-01

    Silicon pixel modules employing n-in-p planar sensors with an active thickness of 200 μm, produced at CiS, and 100-200 μm thin active/slim edge sensor devices, produced at VTT in Finland have been interconnected to ATLAS FE-I3 and FE-I4 read-out chips. The thin sensors are designed for high energy physics collider experiments to ensure radiation hardness at high fluences. Moreover, the active edge technology of the VTT production maximizes the sensitive region of the assembly, allowing for a reduced overlap of the modules in the pixel layer close to the beam pipe. The CiS production includes also four chip sensors according to the module geometry planned for the outer layers of the upgraded ATLAS pixel detector to be operated at the HL-LHC. The modules have been characterized using radioactive sources in the laboratory and with high precision measurements at beam tests to investigate the hit efficiency and charge collection properties at different bias voltages and particle incidence angles. The performance of the different sensor thicknesses and edge designs are compared before and after irradiation up to a fluence of 1.4 × 1016 neq/cm2.

  11. Investigation of the Design Boundaries of a 3,072 X 2,048 Image Sensor Pixel Array

    NASA Astrophysics Data System (ADS)

    Eid, El-Sayed I.

    2002-09-01

    The practical boundaries surrounding the design of very high resolution image sensors have been studied. The case study used to analyze these practical boundaries is a CMOS photodiode active pixel sensor (APS) image sensor with pixel array format of 3,072 (H) X 2,048 (V). The frame rate of the image sensor is variable up to 30 frames per second (fps), leading to a maximum image data throughput of 180 M pixels per second. The pixel size is 6.0 im, resulting in a pixel fill factor of approximately 48% (implemented in a 0.25 μm CMOS fabrication process) and a 4/3 inch optical format. The resultant die fill factor is approximately 54%. The column-parallel approach, which works well for both the on-chip analog signal processing and analog-to-digital conversion, is adopted. The 10-bit successive approximation ADC was deemed suitable for on-chip integration. The projected total power consumption of the case study image sensor chip is below 200 mW at 3.3-V power supply and below 100 mW at 1.5-V power supply. These power estimates were made for operation at full resolution (6 M pixels per frame) and at maximum frame rate (30 fps), leading to a maximum digital image data throughput of 1.8 G bits per second.

  12. Linear dynamic range enhancement in a CMOS imager

    NASA Technical Reports Server (NTRS)

    Pain, Bedabrata (Inventor)

    2008-01-01

    A CMOS imager with increased linear dynamic range but without degradation in noise, responsivity, linearity, fixed-pattern noise, or photometric calibration comprises a linear calibrated dual gain pixel in which the gain is reduced after a pre-defined threshold level by switching in an additional capacitance. The pixel may include a novel on-pixel latch circuit that is used to switch in the additional capacitance.

  13. High-Sensitivity X-ray Polarimetry with Amorphous Silicon Active-Matrix Pixel Proportional Counters

    NASA Technical Reports Server (NTRS)

    Black, J. K.; Deines-Jones, P.; Jahoda, K.; Ready, S. E.; Street, R. A.

    2003-01-01

    Photoelectric X-ray polarimeters based on pixel micropattern gas detectors (MPGDs) offer order-of-magnitude improvement in sensitivity over more traditional techniques based on X-ray scattering. This new technique places some of the most interesting astronomical observations within reach of even a small, dedicated mission. The most sensitive instrument would be a photoelectric polarimeter at the focus of 2 a very large mirror, such as the planned XEUS. Our efforts are focused on a smaller pathfinder mission, which would achieve its greatest sensitivity with large-area, low-background, collimated polarimeters. We have recently demonstrated a MPGD polarimeter using amorphous silicon thin-film transistor (TFT) readout suitable for the focal plane of an X-ray telescope. All the technologies used in the demonstration polarimeter are scalable to the areas required for a high-sensitivity collimated polarimeter. Leywords: X-ray polarimetry, particle tracking, proportional counter, GEM, pixel readout

  14. Thin active region, type II superlattice photodiode arrays: Single-pixel and focal plane array characterization

    NASA Astrophysics Data System (ADS)

    Little, J. W.; Svensson, S. P.; Beck, W. A.; Goldberg, A. C.; Kennerly, S. W.; Hongsmatip, T.; Winn, M.; Uppal, P.

    2007-02-01

    We have measured the radiometric properties of two midwave infrared photodiode arrays (320×256pixel2 format) fabricated from the same wafer comprising a thin (0.24μm), not intentionally doped InAs /GaSb superlattice between a p-doped GaSb layer and a n-doped InAs layer. One of the arrays was indium bump bonded to a silicon fanout chip to allow for the measurement of properties of individual pixels, and one was bonded to a readout integrated circuit to enable array-scale measurements and infrared imaging. The superlattice layer is thin enough that it is fully depleted at zero bias, and the collection efficiency of photogenerated carriers in the intrinsic region is close to unity. This simplifies the interpretation of photocurrent data as compared with previous measurements made on thick superlattices with complex doping profiles. Superlattice absorption coefficient curves, obtained from measurements of the external quantum efficiency using two different assumptions for optical coupling into the chip, bracket values calculated using an eight-band k •p model. Measurements of the quantum efficiency map of the focal plane array were in good agreement with the single-pixel measurements. Imagery obtained with this focal plane array demonstrates the high uniformity and crystal quality of the type II superlattice material.

  15. Implementation of TDI based digital pixel ROIC with 15μm pixel pitch

    NASA Astrophysics Data System (ADS)

    Ceylan, Omer; Shafique, Atia; Burak, A.; Caliskan, Can; Abbasi, Shahbaz; Yazici, Melik; Gurbuz, Yasar

    2016-05-01

    A 15um pixel pitch digital pixel for LWIR time delay integration (TDI) applications is implemented which occupies one fourth of pixel area compared to previous digital TDI implementation. TDI is implemented on 8 pixels with oversampling rate of 2. ROIC provides 16 bits output with 8 bits of MSB and 8 bits of LSB. Pixel can store 75 M electrons with a quantization noise of 500 electrons. Digital pixel TDI implementation is advantageous over analog counterparts considering power consumption, chip area and signal-to-noise ratio. Digital pixel TDI ROIC is fabricated with 0.18um CMOS process. In digital pixel TDI implementation photocurrent is integrated on a capacitor in pixel and converted to digital data in pixel. This digital data triggers the summation counters which implements TDI addition. After all pixels in a row contribute, the summed data is divided to the number of TDI pixels(N) to have the actual output which is square root of N improved version of a single pixel output in terms of signal-to-noise-ratio (SNR).

  16. PIXEL PUSHER

    NASA Technical Reports Server (NTRS)

    Stanfill, D. F.

    1994-01-01

    Pixel Pusher is a Macintosh application used for viewing and performing minor enhancements on imagery. It will read image files in JPL's two primary image formats- VICAR and PDS - as well as the Macintosh PICT format. VICAR (NPO-18076) handles an array of image processing capabilities which may be used for a variety of applications including biomedical image processing, cartography, earth resources, and geological exploration. Pixel Pusher can also import VICAR format color lookup tables for viewing images in pseudocolor (256 colors). This program currently supports only eight bit images but will work on monitors with any number of colors. Arbitrarily large image files may be viewed in a normal Macintosh window. Color and contrast enhancement can be performed with a graphical "stretch" editor (as in contrast stretch). In addition, VICAR images may be saved as Macintosh PICT files for exporting into other Macintosh programs, and individual pixels can be queried to determine their locations and actual data values. Pixel Pusher is written in Symantec's Think C and was developed for use on a Macintosh SE30, LC, or II series computer running System Software 6.0.3 or later and 32 bit QuickDraw. Pixel Pusher will only run on a Macintosh which supports color (whether a color monitor is being used or not). The standard distribution medium for this program is a set of three 3.5 inch Macintosh format diskettes. The program price includes documentation. Pixel Pusher was developed in 1991 and is a copyrighted work with all copyright vested in NASA. Think C is a trademark of Symantec Corporation. Macintosh is a registered trademark of Apple Computer, Inc.

  17. Design and image-quality performance of high resolution CMOS-based X-ray imaging detectors for digital mammography

    NASA Astrophysics Data System (ADS)

    Cha, B. K.; Kim, J. Y.; Kim, Y. J.; Yun, S.; Cho, G.; Kim, H. K.; Seo, C.-W.; Jeon, S.; Huh, Y.

    2012-04-01

    In digital X-ray imaging systems, X-ray imaging detectors based on scintillating screens with electronic devices such as charge-coupled devices (CCDs), thin-film transistors (TFT), complementary metal oxide semiconductor (CMOS) flat panel imagers have been introduced for general radiography, dental, mammography and non-destructive testing (NDT) applications. Recently, a large-area CMOS active-pixel sensor (APS) in combination with scintillation films has been widely used in a variety of digital X-ray imaging applications. We employed a scintillator-based CMOS APS image sensor for high-resolution mammography. In this work, both powder-type Gd2O2S:Tb and a columnar structured CsI:Tl scintillation screens with various thicknesses were fabricated and used as materials to convert X-ray into visible light. These scintillating screens were directly coupled to a CMOS flat panel imager with a 25 × 50 mm2 active area and a 48 μm pixel pitch for high spatial resolution acquisition. We used a W/Al mammographic X-ray source with a 30 kVp energy condition. The imaging characterization of the X-ray detector was measured and analyzed in terms of linearity in incident X-ray dose, modulation transfer function (MTF), noise-power spectrum (NPS) and detective quantum efficiency (DQE).

  18. Pixel Perfect

    SciTech Connect

    Perrine, Kenneth A.; Hopkins, Derek F.; Lamarche, Brian L.; Sowa, Marianne B.

    2005-09-01

    Biologists and computer engineers at Pacific Northwest National Laboratory have specified, designed, and implemented a hardware/software system for performing real-time, multispectral image processing on a confocal microscope. This solution is intended to extend the capabilities of the microscope, enabling scientists to conduct advanced experiments on cell signaling and other kinds of protein interactions. FRET (fluorescence resonance energy transfer) techniques are used to locate and monitor protein activity. In FRET, it is critical that spectral images be precisely aligned with each other despite disturbances in the physical imaging path caused by imperfections in lenses and cameras, and expansion and contraction of materials due to temperature changes. The central importance of this work is therefore automatic image registration. This runs in a framework that guarantees real-time performance (processing pairs of 1024x1024, 8-bit images at 15 frames per second) and enables the addition of other types of advanced image processing algorithms such as image feature characterization. The supporting system architecture consists of a Visual Basic front-end containing a series of on-screen interfaces for controlling various aspects of the microscope and a script engine for automation. One of the controls is an ActiveX component written in C++ for handling the control and transfer of images. This component interfaces with a pair of LVDS image capture boards and a PCI board containing a 6-million gate Xilinx Virtex-II FPGA. Several types of image processing are performed on the FPGA in a pipelined fashion, including the image registration. The FPGA offloads work that would otherwise need to be performed by the main CPU and has a guaranteed real-time throughput. Image registration is performed in the FPGA by applying a cubic warp on one image to precisely align it with the other image. Before each experiment, an automated calibration procedure is run in order to set up the

  19. Fabrication of CMOS image sensors

    NASA Astrophysics Data System (ADS)

    Malinovich, Yacov; Koltin, Ephie; Choen, David; Shkuri, Moshe; Ben-Simon, Meir

    1999-04-01

    In order to provide its customers with sub-micron CMOS fabrication solutions for imaging applications, Tower Semiconductor initiated a project to characterize the optical parameters of Tower's 0.5-micron process. A special characterization test chip was processed using the TS50 process. The results confirmed a high quality process for optical applications. Perhaps the most important result is the process' very low dark current, of 30-50 pA/cm2, using the entire window of process. This very low dark current characteristic was confirmed for a variety of pixel architectures. Additionally, we have succeeded to reduce and virtually eliminate the white spots on large sensor arrays. As a foundry Tower needs to support fabrication of many different imaging products. Therefore we have developed a fabrication methodology that is adjusted to the special needs of optical applications. In order to establish in-line process monitoring of the optical parameters, Tower places a scribe line optical test chip that enables wafer level measurements of the most important parameters, ensuring the optical quality and repeatability of the process. We have developed complementary capabilities like in house deposition of color filter and fabrication of very large are dice using sub-micron CMOS technologies. Shellcase and Tower are currently developing a new CMOS image sensor optical package.

  20. Pixel Detectors For Diffraction Experiments At The Swiss Light Source

    SciTech Connect

    Huelsen, G.; Eikenberry, E.F.; Schmitt, B.; Schulze-Briese, C.; Tomizaki, T.; Stampanoni, M.; Willmott, P.; Patterson, B.; Broennimann, Ch.; Horisberger, R.; Toyokawa, H.; Borchert, G. L.

    2004-05-12

    The PILATUS detector (Pixel Apparatus for the SLS) is a large, quantum-limited area X-ray detector for protein crystallography which is currently under construction. Its basic units are modules with 16 CMOS chips bump-bonded to a large, continuously sensitive silicon sensor with 157x366 pixels of 217x217 {mu}m2, leading to an active area of 34x80 mm2. With a counting circuit in each pixel, X-rays are detected in single photon counting mode, leading to excellent, noise-free data. The main properties of the detector are an energy range of 6 to 30 keV, no back-ground due to leakage current or readout-noise, fast read-out time of 6.7 ms, a rate/pixel >104/s and a PSF of one pixel. PILATUS detectors are installed at the SLS X06SA protein crystallography beamline, and at both the surface diffraction (SD) station and the radiography and tomography (XTM) station of beamline X04SA. The detectors are operated at room temperature and thus are very easy to use. Experiments benefit from the ability to detect very weak diffraction spots with high precision. At the SD station and at the XTM station, which is equipped with a Bragg magnifier, diffraction, radiography and tomography experiments showed promising results. At beamline X06SA, a three-module array (1120x157 pixels) with a readout time of 6.7 ms was tested. This system was used to collect fine phi-sliced protein crystal data in continuous sample rotation mode in which the crystal was continuously rotated with a slow angular velocity of 0.04 deg./s without any shutter operation. Exposure time per frame ranged from 100 ms to a few seconds, depending on the crystal. These initial experiments show the potential of this method.

  1. A 0.18-µm CMOS Array Sensor for Integrated Time-Resolved Fluorescence Detection

    PubMed Central

    Huang, Ta-chien D.; Sorgenfrei, Sebastian; Gong, Ping; Levicky, Rastislav; Shepard, Kenneth L.

    2010-01-01

    This paper describes the design of an active, integrated CMOS sensor array for fluorescence applications which enables time-gated, time-resolved fluorescence spectroscopy. The 64-by-64 array is sensitive to photon densities as low as 8.8 × 106 photons/cm2 with 64-point averaging and, through a differential pixel design, has a measured impulse response of better than 800 ps. Applications include both active microarrays and high-frame-rate imagers for fluorescence lifetime imaging microscopy. PMID:20436922

  2. Low-dose performance of wafer-scale CMOS-based X-ray detectors

    NASA Astrophysics Data System (ADS)

    Maes, Willem H.; Peters, Inge M.; Smit, Chiel; Kessener, Yves; Bosiers, Jan

    2015-03-01

    Compared to published amorphous-silicon (TFT) based X-ray detectors, crystalline silicon CMOS-based active-pixel detectors exploit the benefits of low noise, high speed, on-chip integration and featuring offered by CMOS technology. This presentation focuses on the specific advantage of high image quality at very low dose levels. The measurement of very low dose performance parameters like Detective Quantum Efficiency (DQE) and Noise Equivalent Dose (NED) is a challenge by itself. Second-order effects like defect pixel behavior, temporal and quantization noise effects, dose measurement accuracy and limitation of the x-ray source settings will influence the measurements at very low dose conditions. Using an analytical model to predict the low dose behavior of a detector from parameters extracted from shot-noise limited dose levels is presented. These models can also provide input for a simulation environment for optimizing the performance of future detectors. In this paper, models for predicting NED and the DQE at very low dose are compared to measurements on different CMOS detectors. Their validity for different sensor and optical stack combinations as well as for different x-ray beam conditions was validated.

  3. Radiation damage studies on STAR250 CMOS sensor at 300 keV for electron microscopy

    NASA Astrophysics Data System (ADS)

    Faruqi, A. R.; Henderson, R.; Holmes, J.

    2006-09-01

    There is a pressing need for better electronic detectors to replace film for recording high-resolution images using electron cryomicroscopy. Our previous work has shown that direct electron detection in CMOS sensors is promising in terms of resolution and efficiency at 120 keV [A.R. Faruqi, R. Henderson, M. Prydderch, R. Turchetta, P. Allport, A. Evans, Nucl. Instr. and Meth. 546 (2005) 170], but in addition, the detectors must not be damaged by the electron irradiation. We now present new measurements on the radiation tolerance of a 25 μm pitch CMOS active-pixel sensor, the STAR250, which was designed by FillFactory using radiation-hard technology for space applications. Our tests on the STAR250 aimed to establish the imaging performance at 300 keV following irradiation. The residual contrast, measured on shadow images of a 300 mesh grid, was >80% after corrections for increased dark current, following irradiation with up to 5×10 7 electrons/pixel (equivalent to 80,000 electron/μm 2). A CMOS sensor with this degree of radiation tolerance would survive a year of normal usage for low-dose electron cryomicroscopy, which is a very useful advance.

  4. A new architecture of current-mode CMOS TDI Sensor

    NASA Astrophysics Data System (ADS)

    Ji, Cheng; Chen, Yongping

    2015-10-01

    Nowadays, CMOS sensors still suffer from the problem of low SNR, especially in the stage of low illumination and high relative scanning velocity. Lots of methods have been develop to overcome this problem. Among these researches, TDI (Time Delay Integration) architecture is a more natural choice, which is natively supported by CCD sensors. In this paper a new kind of proposed current-mode sensor is used to achieve TDI operation in analog domain. The circuit is composed of three main parts. At first, a current-type pixel is proposed, in which the active MOSFET is operated in the triode region to ensure the output current is linearly dependent on the gate voltage and avoid the reduction of threshold voltage in the traditional voltage mode pixels, such as 3T, 4T which use the source followers as its active part. Then a discrete double sampling (DDS) unit, which is operated in the form of currents is used to efficiently reduce the fixed pattern noise (FPN) and make the output is independent of reset voltage of pixels. For accumulation, an improved current mirror adder under controlled of timing circuits is proposed to overcome the problem of saturation suffered in voltage domain. Some main noise sources, especially come from analog sample and holds capacitors and switches is analyzed. Finally, simulation results with CSMC 0.5um technology and Cadence IC show that the proposed method is reasonable and efficient to improve the SNR.

  5. Vertical Isolation for Photodiodes in CMOS Imagers

    NASA Technical Reports Server (NTRS)

    Pain, Bedabrata

    2008-01-01

    In a proposed improvement in complementary metal oxide/semi conduct - or (CMOS) image detectors, two additional implants in each pixel would effect vertical isolation between the metal oxide/semiconductor field-effect transistors (MOSFETs) and the photodiode of the pixel. This improvement is expected to enable separate optimization of the designs of the photodiode and the MOSFETs so as to optimize their performances independently of each other. The purpose to be served by enabling this separate optimization is to eliminate or vastly reduce diffusion cross-talk, thereby increasing sensitivity, effective spatial resolution, and color fidelity while reducing noise.

  6. Radiation hardness of two CMOS prototypes for the ATLAS HL-LHC upgrade project.

    NASA Astrophysics Data System (ADS)

    Huffman, B. T.; Affolder, A.; Arndt, K.; Bates, R.; Benoit, M.; Di Bello, F.; Blue, A.; Bortoletto, D.; Buckland, M.; Buttar, C.; Caragiulo, P.; Das, D.; Dopke, J.; Dragone, A.; Ehrler, F.; Fadeyev, V.; Galloway, Z.; Grabas, H.; Gregor, I. M.; Grenier, P.; Grillo, A.; Hoeferkamp, M.; Hommels, L. B. A.; John, J.; Kanisauskas, K.; Kenney, C.; Kramberger, J.; Liang, Z.; Mandić, I.; Maneuski, D.; Martinez-Mckinney, F.; McMahon, S.; Meng, L.; Mikuž, M.; Muenstermann, D.; Nickerson, R.; Perić, I.; Phillips, P.; Plackett, R.; Rubbo, F.; Segal, J.; Seidel, S.; Seiden, A.; Shipsey, I.; Song, W.; Stanitzki, M.; Su, D.; Tamma, C.; Turchetta, R.; Vigani, L.; Volk, J.; Wang, R.; Warren, M.; Wilson, F.; Worm, S.; Xiu, Q.; Zhang, J.; Zhu, H.

    2016-02-01

    The LHC luminosity upgrade, known as the High Luminosity LHC (HL-LHC), will require the replacement of the existing silicon strip tracker and the transistion radiation tracker. Although a baseline design for this tracker exists the ATLAS collaboration and other non-ATLAS groups are exploring the feasibility of using CMOS Monolithic Active Pixel Sensors (MAPS) which would be arranged in a strip-like fashion and would take advantage of the service and support structure already being developed for the upgrade. Two test devices made with the AMS H35 process (a High voltage or HV CMOS process) have been subjected to various radiation environments and have performed well. The results of these tests are presented in this paper.

  7. c-mos and cdc2 Cooperate in the Translational Activation of Fibroblast Growth Factor Receptor-1 during Xenopus Oocyte Maturation

    PubMed Central

    Culp, Patricia A.; Musci, Thomas J.

    1999-01-01

    During oocyte maturation in Xenopus, previously quiescent maternal mRNAs are translationally activated at specific times. We hypothesized that the translational recruitment of individual messages is triggered by particular cellular events and investigated the potential for known effectors of the meiotic cell cycle to activate the translation of the FGF receptor-1 (XFGFR) maternal mRNA. We found that both c-mos and cdc2 activate the translation of XFGFR. However, although oocytes matured by injection of recombinant cdc2/cyclin B translate normal levels of XFGFR protein, c-mos depletion reduces the level of XFGFR protein induced by cdc2/cyclin B injection. In oocytes blocked for cdc2 activity, injection of mos RNA induced low levels of XFGFR protein, independent of MAPK activity. Through the use of injected reporter RNAs, we show that the XFGFR 3′ untranslated region inhibitory element is completely derepressed by cdc2 alone. In addition, we identified a new inhibitory element through which both mos and cdc2 activate translation. We found that cdc2 derepresses translation in the absence of polyadenylation, whereas mos requires poly(A) extension to activate XFGFR translation. Our results demonstrate that mos and cdc2, in addition to functioning as key regulators of the meiotic cell cycle, cooperate in the translational activation of a specific maternal mRNA during oocyte maturation. PMID:10564256

  8. An investigation of signal performance enhancements achieved through innovative pixel design across several generations of indirect detection, active matrix, flat-panel arrays

    SciTech Connect

    Antonuk, Larry E.; Zhao Qihua; El-Mohri, Youcef; Du Hong; Wang Yi; Street, Robert A.; Ho, Jackson; Weisfield, Richard; Yao, William

    2009-07-15

    Active matrix flat-panel imager (AMFPI) technology is being employed for an increasing variety of imaging applications. An important element in the adoption of this technology has been significant ongoing improvements in optical signal collection achieved through innovations in indirect detection array pixel design. Such improvements have a particularly beneficial effect on performance in applications involving low exposures and/or high spatial frequencies, where detective quantum efficiency is strongly reduced due to the relatively high level of additive electronic noise compared to signal levels of AMFPI devices. In this article, an examination of various signal properties, as determined through measurements and calculations related to novel array designs, is reported in the context of the evolution of AMFPI pixel design. For these studies, dark, optical, and radiation signal measurements were performed on prototype imagers incorporating a variety of increasingly sophisticated array designs, with pixel pitches ranging from 75 to 127 {mu}m. For each design, detailed measurements of fundamental pixel-level properties conducted under radiographic and fluoroscopic operating conditions are reported and the results are compared. A series of 127 {mu}m pitch arrays employing discrete photodiodes culminated in a novel design providing an optical fill factor of {approx}80% (thereby assuring improved x-ray sensitivity), and demonstrating low dark current, very low charge trapping and charge release, and a large range of linear signal response. In two of the designs having 75 and 90 {mu}m pitches, a novel continuous photodiode structure was found to provide fill factors that approach the theoretical maximum of 100%. Both sets of novel designs achieved large fill factors by employing architectures in which some, or all of the photodiode structure was elevated above the plane of the pixel addressing transistor. Generally, enhancement of the fill factor in either discrete or

  9. An investigation of signal performance enhancements achieved through innovative pixel design across several generations of indirect detection, active matrix, flat-panel arrays

    PubMed Central

    Antonuk, Larry E.; Zhao, Qihua; El-Mohri, Youcef; Du, Hong; Wang, Yi; Street, Robert A.; Ho, Jackson; Weisfield, Richard; Yao, William

    2009-01-01

    Active matrix flat-panel imager (AMFPI) technology is being employed for an increasing variety of imaging applications. An important element in the adoption of this technology has been significant ongoing improvements in optical signal collection achieved through innovations in indirect detection array pixel design. Such improvements have a particularly beneficial effect on performance in applications involving low exposures and∕or high spatial frequencies, where detective quantum efficiency is strongly reduced due to the relatively high level of additive electronic noise compared to signal levels of AMFPI devices. In this article, an examination of various signal properties, as determined through measurements and calculations related to novel array designs, is reported in the context of the evolution of AMFPI pixel design. For these studies, dark, optical, and radiation signal measurements were performed on prototype imagers incorporating a variety of increasingly sophisticated array designs, with pixel pitches ranging from 75 to 127 μm. For each design, detailed measurements of fundamental pixel-level properties conducted under radiographic and fluoroscopic operating conditions are reported and the results are compared. A series of 127 μm pitch arrays employing discrete photodiodes culminated in a novel design providing an optical fill factor of ∼80% (thereby assuring improved x-ray sensitivity), and demonstrating low dark current, very low charge trapping and charge release, and a large range of linear signal response. In two of the designs having 75 and 90 μm pitches, a novel continuous photodiode structure was found to provide fill factors that approach the theoretical maximum of 100%. Both sets of novel designs achieved large fill factors by employing architectures in which some, or all of the photodiode structure was elevated above the plane of the pixel addressing transistor. Generally, enhancement of the fill factor in either discrete or continuous

  10. Imaging properties of pixellated scintillators with deep pixels

    NASA Astrophysics Data System (ADS)

    Barber, H. Bradford; Fastje, David; Lemieux, Daniel; Grim, Gary P.; Furenlid, Lars R.; Miller, Brian W.; Parkhurst, Philip; Nagarkar, Vivek V.

    2014-09-01

    We have investigated the light-transport properties of scintillator arrays with long, thin pixels (deep pixels) for use in high-energy gamma-ray imaging. We compared 10x10 pixel arrays of YSO:Ce, LYSO:Ce and BGO (1mm x 1mm x 20 mm pixels) made by Proteus, Inc. with similar 10x10 arrays of LSO:Ce and BGO (1mm x 1mm x 15mm pixels) loaned to us by Saint-Gobain. The imaging and spectroscopic behaviors of these scintillator arrays are strongly affected by the choice of a reflector used as an inter-pixel spacer (3M ESR in the case of the Proteus arrays and white, diffuse-reflector for the Saint-Gobain arrays). We have constructed a 3700-pixel LYSO:Ce Prototype NIF Gamma-Ray Imager for use in diagnosing target compression in inertial confinement fusion. This system was tested at the OMEGA Laser and exhibited significant optical, inter-pixel cross-talk that was traced to the use of a single-layer of ESR film as an inter-pixel spacer. We show how the optical cross-talk can be mapped, and discuss correction procedures. We demonstrate a 10x10 YSO:Ce array as part of an iQID (formerly BazookaSPECT) imager and discuss issues related to the internal activity of 176Lu in LSO:Ce and LYSO:Ce detectors.

  11. Imaging properties of pixellated scintillators with deep pixels

    PubMed Central

    Barber, H. Bradford; Fastje, David; Lemieux, Daniel; Grim, Gary P.; Furenlid, Lars R.; Miller, Brian W.; Parkhurst, Philip; Nagarkar, Vivek V.

    2015-01-01

    We have investigated the light-transport properties of scintillator arrays with long, thin pixels (deep pixels) for use in high-energy gamma-ray imaging. We compared 10×10 pixel arrays of YSO:Ce, LYSO:Ce and BGO (1mm × 1mm × 20 mm pixels) made by Proteus, Inc. with similar 10×10 arrays of LSO:Ce and BGO (1mm × 1mm × 15mm pixels) loaned to us by Saint-Gobain. The imaging and spectroscopic behaviors of these scintillator arrays are strongly affected by the choice of a reflector used as an inter-pixel spacer (3M ESR in the case of the Proteus arrays and white, diffuse-reflector for the Saint-Gobain arrays). We have constructed a 3700-pixel LYSO:Ce Prototype NIF Gamma-Ray Imager for use in diagnosing target compression in inertial confinement fusion. This system was tested at the OMEGA Laser and exhibited significant optical, inter-pixel cross-talk that was traced to the use of a single-layer of ESR film as an inter-pixel spacer. We show how the optical cross-talk can be mapped, and discuss correction procedures. We demonstrate a 10×10 YSO:Ce array as part of an iQID (formerly BazookaSPECT) imager and discuss issues related to the internal activity of 176Lu in LSO:Ce and LYSO:Ce detectors. PMID:26236070

  12. High-performance VGA-resolution digital color CMOS imager

    NASA Astrophysics Data System (ADS)

    Agwani, Suhail; Domer, Steve; Rubacha, Ray; Stanley, Scott

    1999-04-01

    This paper discusses the performance of a new VGA resolution color CMOS imager developed by Motorola on a 0.5micrometers /3.3V CMOS process. This fully integrated, high performance imager has on chip timing, control, and analog signal processing chain for digital imaging applications. The picture elements are based on 7.8micrometers active CMOS pixels that use pinned photodiodes for higher quantum efficiency and low noise performance. The image processing engine includes a bank of programmable gain amplifiers, line rate clamping for dark offset removal, real time auto white balancing, per column gain and offset calibration, and a 10 bit pipelined RSD analog to digital converter with a programmable input range. Post ADC signal processing includes features such as bad pixel replacement based on user defined thresholds levels, 10 to 8 bit companding and 5 tap FIR filtering. The sensor can be programmed via a standard I2C interface that runs on 3.3V clocks. Programmable features include variable frame rates using a constant frequency master clock, electronic exposure control, continuous or single frame capture, progressive or interlace scanning modes. Each pixel is individually addressable allowing region of interest imaging and image subsampling. The sensor operates with master clock frequencies of up to 13.5MHz resulting in 30FPS. A total programmable gain of 27dB is available. The sensor power dissipation is 400mW at full speed of operation. The low noise design yields a measured 'system on a chip' dynamic range of 50dB thus giving over 8 true bits of resolution. Extremely high conversion gain result in an excellent peak sensitivity of 22V/(mu) J/cm2 or 3.3V/lux-sec. This monolithic image capture and processing engine represent a compete imaging solution making it a true 'camera on a chip'. Yet in its operation it remains extremely easy to use requiring only one clock and a 3.3V power supply. Given the available features and performance levels, this sensor will be

  13. The Nanoelectronics Research Initiative and Beyond CMOS Research Activities in the US

    NASA Astrophysics Data System (ADS)

    Bourianoff, George I.

    2008-03-01

    The six leading Semiconductor Companies in the US have joined forces with Federal and State government to form the Nanoelectronics Research Initiative in 2005. The goal is to find new information processing paradigms, systems and devices which will extend Moore's Law functional scaling into the indefinite future. The research activities are guided by 5 central research vectors which define the scope and content of the program and are listed below. *Computational state variables other than electronic charge *Non-equilibrium systems out of equilibrium with the thermal environment *Novel information transport mechanisms *Nanoscale thermal management *Directed self assembly of complex heterostructures The current NRI research effort consists of 56 projects at 25 universities and 3 research centers in a coherent program where each project is aligned with one or more of the research vectors. During the past two years, significant progress has been made in a number of areas including spin wave, generation, detection and characterization, room temperature DMS materials, femptosecond magnetic domain switching characterization, improved MQCA structures, multiferroic and, magnetoelectric materials and devices, non-conformational metal insulator phase transitions in VO2 and ferromagnetic ring nanodevices. A brief discussion and references will be provided.

  14. Low nickel germanide contact resistances by carrier activation enhancement techniques for germanium CMOS application

    NASA Astrophysics Data System (ADS)

    Miyoshi, Hidenori; Ueno, Tetsuji; Hirota, Yoshihiro; Yamanaka, Junji; Arimoto, Keisuke; Nakagawa, Kiyokazu; Kaitsuka, Takanobu

    2014-01-01

    We fabricated and studied nickel germanide (NiGe) contacts on both n- and p-type germanium (Ge) substrates by applying the carrier activation enhancement (CAE) technique. We achieved a high electron concentration of 8.6 × 1019 cm-3 using a P/Sb co-implant and a record-high hole concentration of 8.4 × 1020 cm-3 using a Ge preamorphization implant and a boron implant. We used the circular transfer length method and two-dimensional DC simulation to determine the specific contact resistivity (ρc). Using the CAE technique, we obtained low ρc values of 6.4 × 10-7 Ω cm2 for the NiGe/n+-Ge contact and 4.0 × 10-8 Ω cm2 for the NiGe/p+-Ge contact. Theoretical calculation of ρc shows that, to achieve a ρc of 1 × 10-8 Ω cm2 as required by the International Technology Roadmap for Semiconductors for the year 2015, contacts on p+-Ge need contact process optimization, while contacts on n+-Ge need further CAE improvement and/or Schottky barrier height reduction.

  15. CMOS APS detector characterization for quantitative X-ray imaging

    NASA Astrophysics Data System (ADS)

    Endrizzi, Marco; Oliva, Piernicola; Golosio, Bruno; Delogu, Pasquale

    2013-03-01

    An X-ray Imaging detector based on CMOS Active Pixel Sensor and structured scintillator is characterized for quantitative X-ray imaging in the energy range 11-30 keV. Linearity, dark noise, spatial resolution and flat-field correction are the characteristics of the detector subject of investigation. The detector response, in terms of mean Analog-to-Digital Unit and noise, is modeled as a function of the energy and intensity of the X-rays. The model is directly tested using monochromatic X-ray beams and it is also indirectly validated by means of polychromatic X-ray-tube spectra. Such a characterization is suitable for quantitative X-ray imaging and the model can be used in simulation studies that take into account the actual performance of the detector.

  16. Modulated CMOS camera for fluorescence lifetime microscopy.

    PubMed

    Chen, Hongtao; Holst, Gerhard; Gratton, Enrico

    2015-12-01

    Widefield frequency-domain fluorescence lifetime imaging microscopy (FD-FLIM) is a fast and accurate method to measure the fluorescence lifetime of entire images. However, the complexity and high costs involved in construction of such a system limit the extensive use of this technique. PCO AG recently released the first luminescence lifetime imaging camera based on a high frequency modulated CMOS image sensor, QMFLIM2. Here we tested and provide operational procedures to calibrate the camera and to improve the accuracy using corrections necessary for image analysis. With its flexible input/output options, we are able to use a modulated laser diode or a 20 MHz pulsed white supercontinuum laser as the light source. The output of the camera consists of a stack of modulated images that can be analyzed by the SimFCS software using the phasor approach. The nonuniform system response across the image sensor must be calibrated at the pixel level. This pixel calibration is crucial and needed for every camera settings, e.g. modulation frequency and exposure time. A significant dependency of the modulation signal on the intensity was also observed and hence an additional calibration is needed for each pixel depending on the pixel intensity level. These corrections are important not only for the fundamental frequency, but also for the higher harmonics when using the pulsed supercontinuum laser. With these post data acquisition corrections, the PCO CMOS-FLIM camera can be used for various biomedical applications requiring a large frame and high speed acquisition. PMID:26500051

  17. Which Photodiode to Use: A Comparison of CMOS-Compatible Structures

    PubMed Central

    Murari, Kartikeya; Etienne-Cummings, Ralph; Thakor, Nitish; Cauwenberghs, Gert

    2010-01-01

    While great advances have been made in optimizing fabrication process technologies for solid state image sensors, the need remains to be able to fabricate high quality photosensors in standard CMOS processes. The quality metrics depend on both the pixel architecture and the photosensitive structure. This paper presents a comparison of three photodiode structures in terms of spectral sensitivity, noise and dark current. The three structures are n+/p-sub, n-well/p-sub and p+/n-well/p-sub. All structures were fabricated in a 0.5 μm 3-metal, 2-poly, n-well process and shared the same pixel and readout architectures. Two pixel structures were fabricated—the standard three transistor active pixel sensor, where the output depends on the photodiode capacitance, and one incorporating an in-pixel capacitive transimpedance amplifier where the output is dependent only on a designed feedback capacitor. The n-well/p-sub diode performed best in terms of sensitivity (an improvement of 3.5 × and 1.6 × over the n+/p-sub and p+/n-well/p-sub diodes, respectively) and signal-to-noise ratio (1.5 × and 1.2 × improvement over the n+/p-sub and p+/n-well/p-sub diodes, respectively) while the p+/n-well/p-sub diode had the minimum (33% compared to other two structures) dark current for a given sensitivity. PMID:20454596

  18. CMOS Image Sensor and System for Imaging Hemodynamic Changes in Response to Deep Brain Stimulation.

    PubMed

    Zhang, Xiao; Noor, Muhammad S; McCracken, Clinton B; Kiss, Zelma H T; Yadid-Pecht, Orly; Murari, Kartikeya

    2016-06-01

    Deep brain stimulation (DBS) is a therapeutic intervention used for a variety of neurological and psychiatric disorders, but its mechanism of action is not well understood. It is known that DBS modulates neural activity which changes metabolic demands and thus the cerebral circulation state. However, it is unclear whether there are correlations between electrophysiological, hemodynamic and behavioral changes and whether they have any implications for clinical benefits. In order to investigate these questions, we present a miniaturized system for spectroscopic imaging of brain hemodynamics. The system consists of a 144 ×144, [Formula: see text] pixel pitch, high-sensitivity, analog-output CMOS imager fabricated in a standard 0.35 μm CMOS process, along with a miniaturized imaging system comprising illumination, focusing, analog-to-digital conversion and μSD card based data storage. This enables stand alone operation without a computer, nor electrical or fiberoptic tethers. To achieve high sensitivity, the pixel uses a capacitive transimpedance amplifier (CTIA). The nMOS transistors are in the pixel while pMOS transistors are column-parallel, resulting in a fill factor (FF) of 26%. Running at 60 fps and exposed to 470 nm light, the CMOS imager has a minimum detectable intensity of 2.3 nW/cm(2) , a maximum signal-to-noise ratio (SNR) of 49 dB at 2.45 μW/cm(2) leading to a dynamic range (DR) of 61 dB while consuming 167 μA from a 3.3 V supply. In anesthetized rats, the system was able to detect temporal, spatial and spectral hemodynamic changes in response to DBS. PMID:26357405

  19. Reliability design of CMOS image sensor for space applications

    NASA Astrophysics Data System (ADS)

    Xie, Ning; Chen, Shijun; Chen, Yongping

    2013-08-01

    In space applications, sensors work in very harsh space environment. Thus the reliability design must be carefully considered. This paper addresses the techniques which effectively increase the reliability of CMOS image sensors. A radiation tolerant pixel design which is implemented in a sun tracker sensor is presented. Measurement results of total dose radiation, SEL, SEU, etc prove the radiation immunity of the sensor.

  20. Direct readout of gaseous detectors with tiled CMOS circuits

    NASA Astrophysics Data System (ADS)

    Visschers, J. L.; Blanco Carballo, V.; Chefdeville, M.; Colas, P.; van der Graaf, H.; Schmitz, J.; Smits, S.; Timmermans, J.

    2007-03-01

    A coordinated design effort is underway, exploring the three-dimensional direct readout of gaseous detectors by an anode plate equipped with a tiled array of many CMOS pixel readout ASICs, having amplification grids integrated on their topsides and being contacted on their backside.

  1. CMOS cassette for digital upgrade of film-based mammography systems

    NASA Astrophysics Data System (ADS)

    Baysal, Mehmet A.; Toker, Emre

    2006-03-01

    While full-field digital mammography (FFDM) technology is gaining clinical acceptance, the overwhelming majority (96%) of the installed base of mammography systems are conventional film-screen (FSM) systems. A high performance, and economical digital cassette based product to conveniently upgrade FSM systems to FFDM would accelerate the adoption of FFDM, and make the clinical and technical advantages of FFDM available to a larger population of women. The planned FFDM cassette is based on our commercial Digital Radiography (DR) cassette for 10 cm x 10 cm field-of-view spot imaging and specimen radiography, utilizing a 150 micron columnar CsI(Tl) scintillator and 48 micron active-pixel CMOS sensor modules. Unlike a Computer Radiography (CR) cassette, which requires an external digitizer, our DR cassette transfers acquired images to a display workstation within approximately 5 seconds of exposure, greatly enhancing patient flow. We will present the physical performance of our prototype system against other FFDM systems in clinical use today, using established objective criteria such as the Modulation Transfer Function (MTF), Detective Quantum Efficiency (DQE), and subjective criteria, such as a contrast-detail (CD-MAM) observer performance study. Driven by the strong demand from the computer industry, CMOS technology is one of the lowest cost, and the most readily accessible technologies available for FFDM today. Recent popular use of CMOS imagers in high-end consumer cameras have also resulted in significant advances in the imaging performance of CMOS sensors against rivaling CCD sensors. This study promises to take advantage of these unique features to develop the first CMOS based FFDM upgrade cassette.

  2. Current-mode CMOS hybrid image sensor

    NASA Astrophysics Data System (ADS)

    Benyhesan, Mohammad Kassim

    Digital imaging is growing rapidly making Complimentary Metal-Oxide-Semi conductor (CMOS) image sensor-based cameras indispensable in many modern life devices like cell phones, surveillance devices, personal computers, and tablets. For various purposes wireless portable image systems are widely deployed in many indoor and outdoor places such as hospitals, urban areas, streets, highways, forests, mountains, and towers. However, the increased demand on high-resolution image sensors and improved processing features is expected to increase the power consumption of the CMOS sensor-based camera systems. Increased power consumption translates into a reduced battery life-time. The increased power consumption might not be a problem if there is access to a nearby charging station. On the other hand, the problem arises if the image sensor is located in widely spread areas, unfavorable to human intervention, and difficult to reach. Given the limitation of energy sources available for wireless CMOS image sensor, an energy harvesting technique presents a viable solution to extend the sensor life-time. Energy can be harvested from the sun light or the artificial light surrounding the sensor itself. In this thesis, we propose a current-mode CMOS hybrid image sensor capable of energy harvesting and image capture. The proposed sensor is based on a hybrid pixel that can be programmed to perform the task of an image sensor and the task of a solar cell to harvest energy. The basic idea is to design a pixel that can be configured to exploit its internal photodiode to perform two functions: image sensing and energy harvesting. As a proof of concept a 40 x 40 array of hybrid pixels has been designed and fabricated in a standard 0.5 microm CMOS process. Measurement results show that up to 39 microW of power can be harvested from the array under 130 Klux condition with an energy efficiency of 220 nJ /pixel /frame. The proposed image sensor is a current-mode image sensor which has several

  3. CMOS digital intra-oral sensor for x-ray radiography

    NASA Astrophysics Data System (ADS)

    Liu, Xinqiao; Byczko, Andrew; Choi, Marcus; Chung, Lap; Do, Hung; Fowler, Boyd; Ispasoiu, Radu; Joshi, Kumar; Miller, Todd; Nagy, Alex; Reaves, David; Rodricks, Brian; Teeter, Doug; Wang, George; Xiao, Feng

    2011-03-01

    In this paper, we present a CMOS digital intra-oral sensor for x-ray radiography. The sensor system consists of a custom CMOS imager, custom scintillator/fiber optics plate, camera timing and digital control electronics, and direct USB communication. The CMOS imager contains 1700 x 1346 pixels. The pixel size is 19.5um x 19.5um. The imager was fabricated with a 0.18um CMOS imaging process. The sensor and CMOS imager design features chamfered corners for patient comfort. All camera functions were integrated within the sensor housing and a standard USB cable was used to directly connect the intra-oral sensor to the host computer. The sensor demonstrated wide dynamic range from 5uGy to 1300uGy and high image quality with a SNR of greater than 160 at 400uGy dose. The sensor has a spatial resolution more than 20 lp/mm.

  4. Theoretical performance analysis for CMOS based high resolution detectors.

    PubMed

    Jain, Amit; Bednarek, Daniel R; Rudin, Stephen

    2013-03-01

    High resolution imaging capabilities are essential for accurately guiding successful endovascular interventional procedures. Present x-ray imaging detectors are not always adequate due to their inherent limitations. The newly-developed high-resolution micro-angiographic fluoroscope (MAF-CCD) detector has demonstrated excellent clinical image quality; however, further improvement in performance and physical design may be possible using CMOS sensors. We have thus calculated the theoretical performance of two proposed CMOS detectors which may be used as a successor to the MAF. The proposed detectors have a 300 μm thick HL-type CsI phosphor, a 50 μm-pixel CMOS sensor with and without a variable gain light image intensifier (LII), and are designated MAF-CMOS-LII and MAF-CMOS, respectively. For the performance evaluation, linear cascade modeling was used. The detector imaging chains were divided into individual stages characterized by one of the basic processes (quantum gain, binomial selection, stochastic and deterministic blurring, additive noise). Ranges of readout noise and exposure were used to calculate the detectors' MTF and DQE. The MAF-CMOS showed slightly better MTF than the MAF-CMOS-LII, but the MAF-CMOS-LII showed far better DQE, especially for lower exposures. The proposed detectors can have improved MTF and DQE compared with the present high resolution MAF detector. The performance of the MAF-CMOS is excellent for the angiography exposure range; however it is limited at fluoroscopic levels due to additive instrumentation noise. The MAF-CMOS-LII, having the advantage of the variable LII gain, can overcome the noise limitation and hence may perform exceptionally for the full range of required exposures; however, it is more complex and hence more expensive. PMID:24353390

  5. A safety monitoring system for taxi based on CMOS imager

    NASA Astrophysics Data System (ADS)

    Liu, Zhi

    2005-01-01

    CMOS image sensors now become increasingly competitive with respect to their CCD counterparts, while adding advantages such as no blooming, simpler driving requirements and the potential of on-chip integration of sensor, analogue circuitry, and digital processing functions. A safety monitoring system for taxi based on cmos imager that can record field situation when unusual circumstance happened is described in this paper. The monitoring system is based on a CMOS imager (OV7120), which can output digital image data through parallel pixel data port. The system consists of a CMOS image sensor, a large capacity NAND FLASH ROM, a USB interface chip and a micro controller (AT90S8515). The structure of whole system and the test data is discussed and analyzed in detail.

  6. High dynamic range active pixel sensor arrays for digital x-ray imaging using a-Si:H

    SciTech Connect

    Lai, Jackson; Nathan, Arokia; Rowlands, John

    2006-05-15

    Hydrogenated amorphous silicon (a-Si:H) active matrix flat panel imagers have gained considerable significance in large area digital imaging applications, in view of their large area readout capability. Current interests lie in a multifaceted a-Si:H array which is compatible with multiple x-ray imaging modalities. This concept entails a single detector system with sufficient dynamic range and variable signal gain. This article reports on an active pixel sensor (APS) array with high dynamic range and programable gain for multimodality x-ray imaging. Initial results have demonstrated sensitivity from subpicoampere to nanoampere photocurrent, which proves amenable for both low-dosage dynamic imaging and high input static imaging. In addition, the programable system signal gain alleviates problems such as output saturation and ensures signal readout linearity to further improve the exploitable dynamic range. Together with external amplification, this APS circuit delivers the performance needed in terms of signal gain, dynamic range, and readout rate entailed by fluoroscopic and radiographic imaging applications.

  7. Proton-induced Random Telegraph Signal in the CMOS imaging sensor for JANUS, the visible imaging telescope on JUICE

    NASA Astrophysics Data System (ADS)

    Winstone, G. P.; Soman, M. R.; Allanwood, E. A. H.; Holland, A. D.; Gow, J. P. D.; Stefanov, K.; Leese, M.

    2015-09-01

    JUpiter ICy moons Explorer (JUICE) is an ESA L class mission due for launch in 2022 as part of the agency's Cosmic Vision program [1][2]. The primary science goal is to explore and characterise Jupiter and several of its potentially habitable icy moons, particularly Ganymede, Europa and Callisto. The JANUS instrument is designated to be the scientific imager on-board the spacecraft with a wavelength range between 400 nm and 1000 nm and consists of a catoptric telescope coupled to a CMOS detector [3], specifically the CIS115 monolithic active pixel sensor supplied by e2v technologies[3]. A CMOS sensor has been chosen due to a combination of the high radiation tolerance required for all systems aboard the spacecraft and its capability of operating with integration times as low as 1 ms, which is required to prevent blur when imaging the moons at fast ground velocities since the camera has no mechanical shutter. However, an important consideration of using CMOS in high radiation environments is the generation of defects or defect clusters that result in pixels exhibiting Random Telegraph Signal (RTS)[5]. A study of RTS effects in the CIS115 has been undertaken, and the method applied to identify pixels in the array that display RTS behaviour is discussed and individual RTS-exhibiting pixels are characterised. The changes observed in RTS behaviour following irradiation of the CIS115 with protons is presented and the temperature dependence of the RTS behaviour is studied. The implications on the camera design and imaging requirements of the mission are examined.

  8. Binary CMOS image sensor with a gate/body-tied MOSFET-type photodetector for high-speed operation

    NASA Astrophysics Data System (ADS)

    Choi, Byoung-Soo; Jo, Sung-Hyun; Bae, Myunghan; Kim, Sang-Hwan; Shin, Jang-Kyoo

    2016-05-01

    In this paper, a binary complementary metal oxide semiconductor (CMOS) image sensor with a gate/body-tied (GBT) metal oxide semiconductor field effect transistor (MOSFET)-type photodetector is presented. The sensitivity of the GBT MOSFET-type photodetector, which was fabricated using the standard CMOS 0.35-μm process, is higher than the sensitivity of the p-n junction photodiode, because the output signal of the photodetector is amplified by the MOSFET. A binary image sensor becomes more efficient when using this photodetector. Lower power consumptions and higher speeds of operation are possible, compared to the conventional image sensors using multi-bit analog to digital converters (ADCs). The frame rate of the proposed image sensor is over 2000 frames per second, which is higher than those of the conventional CMOS image sensors. The output signal of an active pixel sensor is applied to a comparator and compared with a reference level. The 1-bit output data of the binary process is determined by this level. To obtain a video signal, the 1-bit output data is stored in the memory and is read out by horizontal scanning. The proposed chip is composed of a GBT pixel array (144 × 100), binary-process circuit, vertical scanner, horizontal scanner, and readout circuit. The operation mode can be selected from between binary mode and multi-bit mode.

  9. Silicon nanowires integrated with CMOS circuits for biosensing application

    NASA Astrophysics Data System (ADS)

    Jayakumar, G.; Asadollahi, A.; Hellström, P.-E.; Garidis, K.; Östling, M.

    2014-08-01

    We describe a silicon nanowire (SiNW) biosensor fabricated in a fully depleted SOI CMOS process. The sensor array consists of N by N pixel matrix (N2 pixels or test sites) and 8 input-output (I/O) pins. In each pixel a single crystalline SiNW with 75 by 20 nm cross-section area is defined using sidewall transfer lithography in the SOI layer. The key advantage of the design is that each individual SiNWs can be read-out sequentially and used for real-time charge based detection of molecules in liquids or gases.

  10. Preliminary simulation study of a coincidence Avalanche Pixel Sensor

    NASA Astrophysics Data System (ADS)

    Vignetti, M. M.; Calmon, F.; Cellier, R.; Pittet, P.; Quiquerez, L.; Savoy-Navarro, A.

    2015-06-01

    In this paper a preliminary study of coincidence Avalanche Pixel Sensors (APiX) for High Energy Physics (HEP) applications is presented. In this preliminary work, some PEB prevention techniques found in literature have been studied by TCAD simulations adopting 2D Cylindrical geometrical models and 130nm CMOS process technological data.

  11. IR CMOS: infrared enhanced silicon imaging

    NASA Astrophysics Data System (ADS)

    Pralle, M. U.; Carey, J. E.; Haddad, Homayoon; Vineis, C.; Sickler, J.; Li, X.; Jiang, J.; Sahebi, F.; Palsule, C.; McKee, J.

    2013-06-01

    SiOnyx has developed visible and infrared CMOS image sensors leveraging a proprietary ultrafast laser semiconductor process technology. This technology demonstrates 10 fold improvements in infrared sensitivity over incumbent imaging technology while maintaining complete compatibility with standard CMOS image sensor process flows. Furthermore, these sensitivity enhancements are achieved on a focal plane with state of the art noise performance of 2 electrons/pixel. By capturing light in the visible regime as well as infrared light from the night glow, this sensor technology provides imaging in daytime through twilight and into nighttime conditions. The measured 10x quantum efficiency at the critical 1064 nm laser node enables see spot imaging capabilities in a variety of ambient conditions. The spectral sensitivity is from 400 to 1200 nm.

  12. Development of a large-area CMOS-based detector for real-time x-ray imaging

    NASA Astrophysics Data System (ADS)

    Heo, Sung Kyn; Park, Sung Kyu; Hwang, Sung Ha; Im, Dong Ak; Kosonen, Jari; Kim, Tae Woo; Yun, Seungman; Kim, Ho Kyung

    2010-04-01

    Complementary metal-oxide-semiconductor (CMOS) active pixel sensors (APSs) with high electrical and optical performances are now being attractive for digital radiography (DR) and dental cone-beam computed tomography (CBCT). In this study, we report our prototype CMOS-based detectors capable of real-time imaging. The field-of-view of the detector is 12 × 14.4 cm. The detector employs a CsI:Tl scintillator as an x-ray-to-light converter. The electrical performance of the CMOS APS, such as readout noise and full-well capacity, was evaluated. The x-ray imaging characteristics of the detector were evaluated in terms of characteristic curve, pre-sampling modulation transfer function, noise power spectrum, detective quantum efficiency, and image lag. The overall performance of the detector is demonstrated with phantom images obtained for DR and CBCT applications. The detailed development description and measurement results are addressed. With the results, we suggest that the prototype CMOS-based detector has the potential for CBCT and real-time x-ray imaging applications.

  13. Capacitively coupled hybrid pixel assemblies for the CLIC vertex detector

    NASA Astrophysics Data System (ADS)

    Tehrani, N. Alipour; Arfaoui, S.; Benoit, M.; Dannheim, D.; Dette, K.; Hynds, D.; Kulis, S.; Perić, I.; Petrič, M.; Redford, S.; Sicking, E.; Valerio, P.

    2016-07-01

    The vertex detector at the proposed CLIC multi-TeV linear e+e- collider must have minimal material content and high spatial resolution, combined with accurate time-stamping to cope with the expected high rate of beam-induced backgrounds. One of the options being considered is the use of active sensors implemented in a commercial high-voltage CMOS process, capacitively coupled to hybrid pixel ASICs. A prototype of such an assembly, using two custom designed chips (CCPDv3 as active sensor glued to a CLICpix readout chip), has been characterised both in the lab and in beam tests at the CERN SPS using 120 GeV/c positively charged hadrons. Results of these characterisation studies are presented both for single and dual amplification stages in the active sensor, where efficiencies of greater than 99% have been achieved at -60 V substrate bias, with a single hit resolution of 6.1 μm . Pixel cross-coupling results are also presented, showing the sensitivity to placement precision and planarity of the glue layer.

  14. Faint-meteor survey with a large-format CMOS sensor

    NASA Astrophysics Data System (ADS)

    Watanabe, J.; Enomoto, T.; Terai, T.; Kasuga, T.; Miyazaki, S.; Oota, K.; Muraoka, F.; Onishi, T.; Yamasaki, T.; Mito, H.; Aoki, T.; Soyano, T.; Tarusawa, K.; Matsunaga, N.; Sako, S.; Kobayashi, N.; Doi, M.

    2014-07-01

    For observing faint meteors, we need a large telescope or similar optics, which always give a restriction of the field of view. It is a kind of trade-off between the high sensitivity by using larger telescope and narrower field of view. Reconciling this contradiction, we need a large-format imaging detector together with fast readout for meteor observations. A high-sensitivity CMOS sensor of the large format was developed by Canon Inc. in 2010[1]. Its size is 202 mm×205 mm which makes it the largest one-chip CMOS sensor in the world, and approximately 40 times the size of Canon's largest commercial CMOS sensor as shown in the figure. The number of pixel is 1280×1248. Because the increased size of the new CMOS sensor allows more light to be gathered, it enables shooting in low-light environments. The sensor makes image capture possible in one-hundredth the amount of light required by a 35 mm full-frame CMOS sensor, facilitating the shooting of 60 frame-per-second video with a mere 0.3 lux of illumination. We tried to use this large-format CMOS sensor attached to the prime focus of the 1.05-m (F3.1) Schmidt telescope at the Kiso Observatory, University of Tokyo, for surveying faint meteors. The field of view is 3.3 by 3.3 degrees. Test observations including operation check of the system were carried out in January 2011, September 2011,and December 2012. Images were obtained at a time resolution of 60 frames per second. In this system, the limiting magnitude is estimated to be about 11-12. Because of the limitation of the data storage, full-power observations (14-bit data per 1/60 second) were performed for about one or two hours each night. During the first period, we can count a sporadic meteor every 5 seconds. This is about one order higher detection rate of the faint meteors compared with the previous work[2]. Assuming the height of faint meteors at 100 km, the derived flux of the sporadic meteors is about 5 × 10^{-4} km^{-2} sec^{-1}. The last run was

  15. Progress in voltage and current mode on-chip analog-to-digital converters for CMOS image sensors

    NASA Astrophysics Data System (ADS)

    Panicacci, Roger; Pain, Bedabrata; Zhou, Zhimin; Nakamura, Junichi; Fossum, Eric R.

    1996-03-01

    Two 8 bit successive approximation analog-to-digital converter (ADC) designs and a 12 bit current mode incremental sigma delta ((Sigma) -(Delta) ) ADC have been designed, fabricated, and tested. The successive approximation test chip designs are compatible with active pixel sensor (APS) column parallel architectures with a 20.4 micrometers pitch in a 1.2 micrometers n-well CMOS process and a 40 micrometers pitch in a 2 micrometers n-well CMOS process. The successive approximation designs consume as little as 49 (mu) W at a 500 KHz conversion rate meeting the low power requirements inherent in column parallel architectures. The current mode incremental (Sigma) -(Delta) ADC test chip is designed to be multiplexed among 8 columns in a semi-column parallel current mode APS architecture. The higher accuracy ADC consumes 800 (mu) W at a 5 KHz conversion rate.

  16. The PixFEL project: development of advanced X-ray pixel detectors for application at future FEL facilities

    NASA Astrophysics Data System (ADS)

    Rizzo, G.; Comotti, D.; Fabris, L.; Grassi, M.; Lodola, L.; Malcovati, P.; Manghisoni, M.; Ratti, L.; Re, V.; Traversi, G.; Vacchi, C.; Batignani, G.; Bettarini, S.; Casarosa, G.; Forti, F.; Morsani, F.; Paladino, A.; Paoloni, E.; Dalla Betta, G.-F.; Pancheri, L.; Verzellesi, G.; Xu, H.; Mendicino, R.; Benkechkache, M. A.

    2015-02-01

    The PixFEL project aims to develop an advanced X-ray camera for imaging suited for the demanding requirements of next generation free electron laser (FEL) facilities. New technologies can be deployed to boost the performance of imaging detectors as well as future pixel devices for tracking. In the first phase of the PixFEL project, approved by the INFN, the focus will be on the development of the microelectronic building blocks, carried out with a 65 nm CMOS technology, implementing a low noise analog front-end channel with high dynamic range and compression features, a low power ADC and high density memory. At the same time PixFEL will investigate and implement some of the enabling technologies to assembly a seamless large area X-ray camera composed by a matrix of multilayer four-side buttable tiles. A pixel matrix with active edge will be developed to minimize the dead area of the sensor layer. Vertical interconnection of two CMOS tiers will be explored to build a four-side buttable readout chip with small pixel pitch and all the on-board required functionalities. The ambitious target requirements of the new pixel device are: single photon resolution, 1 to 104 photons @ 1 keV to 10 keV input dynamic range, 10-bit analog to digital conversion up to 5 MHz, 1 kevent in-pixel memory and 100 μm pixel pitch. The long term goal of PixFEL will be the development of a versatile X-ray camera to be operated either in burst mode (European XFEL), or in continuous mode to cope with the high frame rates foreseen for the upgrade phase of the LCLS-II at SLAC.

  17. Prototyping of an HV-CMOS demonstrator for the High Luminosity-LHC upgrade

    NASA Astrophysics Data System (ADS)

    Vilella, E.; Benoit, M.; Casanova, R.; Casse, G.; Ferrere, D.; Iacobucci, G.; Peric, I.; Vossebeld, J.

    2016-01-01

    HV-CMOS sensors can offer important advantages in terms of material budget, granularity and cost for large area tracking systems in high energy physics experiments. This article presents the design and simulated results of an HV-CMOS pixel demonstrator for the High Luminosity-LHC. The pixel demonstrator has been designed in the 0.35 μm HV-CMOS process from ams AG and submitted for fabrication through an engineering run. To improve the response of the sensor, different wafers with moderate to high substrate resistivities are used to fabricate the design. The prototype consists of four large analog and standalone matrices with several pixel flavours, which are all compatible for readout with the FE-I4 ASIC. Details about the matrices and the pixel flavours are provided in this article.

  18. Development of low read noise high conversion gain CMOS image sensor for photon counting level imaging

    NASA Astrophysics Data System (ADS)

    Seo, Min-Woong; Kawahito, Shoji; Kagawa, Keiichiro; Yasutomi, Keita

    2016-05-01

    A CMOS image sensor with deep sub-electron read noise and high pixel conversion gain has been developed. Its performance is recognized through image outputs from an area image sensor, confirming the capability of photoelectroncounting- level imaging. To achieve high conversion gain, the proposed pixel has special structures to reduce the parasitic capacitances around FD node. As a result, the pixel conversion gain is increased due to the optimized FD node capacitance, and the noise performance is also improved by removing two noise sources from power supply. For the first time, high contrast images from the reset-gate-less CMOS image sensor, with less than 0.3e- rms noise level, have been generated at an extremely low light level of a few electrons per pixel. In addition, the photon-counting capability of the developed CMOS imager is demonstrated by a measurement, photoelectron-counting histogram (PCH).

  19. A new 9T global shutter pixel with CDS technique

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Ma, Cheng; Zhou, Quan; Wang, Xinyang

    2015-04-01

    Benefiting from motion blur free, Global shutter pixel is very widely used in the design of CMOS image sensors for high speed applications such as motion vision, scientifically inspection, etc. In global shutter sensors, all pixel signal information needs to be stored in the pixel first and then waiting for readout. For higher frame rate, we need very fast operation of the pixel array. There are basically two ways for the in pixel signal storage, one is in charge domain, such as the one shown in [1], this needs complicated process during the pixel fabrication. The other one is in voltage domain, one example is the one in [2], this pixel is based on the 4T PPD technology and normally the driving of the high capacitive transfer gate limits the speed of the array operation. In this paper we report a new 9T global shutter pixel based on 3-T partially pinned photodiode (PPPD) technology. It incorporates three in-pixel storage capacitors allowing for correlated double sampling (CDS) and pipeline operation of the array (pixel exposure during the readout of the array). Only two control pulses are needed for all the pixels at the end of exposure which allows high speed exposure control.

  20. Single photon detection and localization accuracy with an ebCMOS camera

    NASA Astrophysics Data System (ADS)

    Cajgfinger, T.; Dominjon, A.; Barbier, R.

    2015-07-01

    The CMOS sensor technologies evolve very fast and offer today very promising solutions to existing issues facing by imaging camera systems. CMOS sensors are very attractive for fast and sensitive imaging thanks to their low pixel noise (1e-) and their possibility of backside illumination. The ebCMOS group of IPNL has produced a camera system dedicated to Low Light Level detection and based on a 640 kPixels ebCMOS with its acquisition system. After reminding the principle of detection of an ebCMOS and the characteristics of our prototype, we confront our camera to other imaging systems. We compare the identification efficiency and the localization accuracy of a point source by four different photo-detection devices: the scientific CMOS (sCMOS), the Charge Coupled Device (CDD), the Electron Multiplying CCD (emCCD) and the Electron Bombarded CMOS (ebCMOS). Our ebCMOS camera is able to identify a single photon source in less than 10 ms with a localization accuracy better than 1 μm. We report as well efficiency measurement and the false positive identification of the ebCMOS camera by identifying more than hundreds of single photon sources in parallel. About 700 spots are identified with a detection efficiency higher than 90% and a false positive percentage lower than 5. With these measurements, we show that our target tracking algorithm can be implemented in real time at 500 frames per second under a photon flux of the order of 8000 photons per frame. These results demonstrate that the ebCMOS camera concept with its single photon detection and target tracking algorithm is one of the best devices for low light and fast applications such as bioluminescence imaging, quantum dots tracking or adaptive optics.

  1. Active pixel and photon counting imagers based on poly-Si TFTs: rewriting the rule book on large area flat panel x-ray devices

    NASA Astrophysics Data System (ADS)

    Antonuk, Larry E.; Koniczek, Martin; El-Mohri, Youcef; Zhao, Qihua

    2009-02-01

    The near-ubiquity of large area, active matrix, flat-panel imagers (AMFPIs) in medical x-ray imaging applications is a testament to the usefulness and adaptability of the relatively simple concept of array pixels based on a single amorphous silicon (a-Si:H) TFT coupled to a pixel storage capacitor. Interestingly, the fundamental advantages of a-Si:H thin film electronics (including compatibility with very large area processing, high radiation damage resistance, and continued development driven by interest in mainstream consumer products) are shared by the rapidly advancing technology of polycrystalline silicon (poly-Si) TFTs. Moreover, the far higher mobilities of poly-Si TFTs, compared to those of a- Si:H, facilitate the creation of faster and more complex circuits than are possible with a-Si:H TFTs, leading to the possibility of new classes of large area, flat panel imagers. Given recent progress in the development of initial poly-Si imager prototypes, the creation of increasingly sophisticated active pixel arrays offering pixel-level amplification, variable gain, very high frame rates, and excellent signal-to-noise performance under all fluoroscopic and radiographic conditions (including very low exposures and high spatial frequencies), appears within reach. In addition, it is conceivable that the properties of poly-Si TFTs could allow the development of large area imagers providing single xray photon counting capabilities. In this article, the factors driving the possible realization of clinically practical active pixel and photon counting imagers based on poly-Si TFTs are described and simple calculational estimates related to photon counting imagers are presented. Finally, the prospect for future development of such imagers is discussed.

  2. An investigation of medical radiation detection using CMOS image sensors in smartphones

    NASA Astrophysics Data System (ADS)

    Kang, Han Gyu; Song, Jae-Jun; Lee, Kwonhee; Nam, Ki Chang; Hong, Seong Jong; Kim, Ho Chul

    2016-07-01

    Medical radiation exposure to patients has increased with the development of diagnostic X-ray devices and multi-channel computed tomography (CT). Despite the fact that the low-dose CT technique can significantly reduce medical radiation exposure to patients, the increasing number of CT examinations has increased the total medical radiation exposure to patients. Therefore, medical radiation exposure to patients should be monitored to prevent cancers caused by diagnostic radiation. However, without using thermoluminescence or glass dosimeters, it is hardly measure doses received by patients during medical examinations accurately. Hence, it is necessary to develop radiation monitoring devices and algorithms that are reasonably priced and have superior radiation detection efficiencies. The aim of this study is to investigate the feasibility of medical dose measurement using complementary metal oxide semiconductor (CMOS) sensors in smartphone cameras with an algorithm to extract the X-ray interacted pixels. We characterized the responses of the CMOS sensors in a smartphone with respect to the X-rays generated by a general diagnostic X-ray system. The characteristics of the CMOS sensors in a smartphone camera, such as dose response linearity, dose rate dependence, energy dependence, angular dependence, and minimum detectable activity were evaluated. The high energy gamma-ray of 662 keV from Cs-137 can be detected using the smartphone camera. The smartphone cameras which employ the developed algorithm can detect medical radiations.

  3. Characteristic of e2v CMOS sensors for astronomical applications

    NASA Astrophysics Data System (ADS)

    Wang, Shiang-Yu; Ling, Hung-Hsu; Hu, Yen-Shan; Geary, John C.; Amato, Stephen M.; Pratlong, Jerome; Pike, Andrew; Jordan, Paul; Lehner, Matthew J.

    2014-07-01

    We report the testing result of e2v CIS 107 CMOS sensor for temperature from 300K to 170K. The CIS 107 sensor is a prototype device with 10 different variations of pixel designs. The sensor has 1500 × 2000, 7 μm pixels with 4 outputs. Each variation covers 1500 × 200 pixels. These are 4T pixels with high resistivity epitaxial silicon and back thinned to 11μm. At room temperature, the several variants of pixels show peak QE higher than 90%, readout noise around 5e- and dark current around 50e-/s/pix. The full well is about 15000 e- due to the limitation of the transfer gate capacitor. The CIS 107 device was further characterized at different device temperatures from 170K to 300K. The readout noise decreases and the full well increases as the device is operated at lower temperature.

  4. Back-side-illuminated 1.4μm pixel with a vertically pinned photodiode based on hole collection, PMOS readout chain and active side-wall passivation

    NASA Astrophysics Data System (ADS)

    Mamdy, Bastien; Roy, François; Ahmed, Nayera; Lu, Guo-Neng

    2015-10-01

    To further improve the characteristics of CMOS image sensors (CIS), we propose a back-side illuminated pixel integrating a vertically pinned and P-type photodiode (which collects holes) and PMOS readout circuitry. It has been designed in a 1.4μm-pitch, a two-transistor (2T) shared readout architecture and fabricated in a combined 65nm and 90nm technology. The vertically pinned photodiode takes up almost the entire volume of the pixel, allowing a full well capacity (FWC) exceeding 7000h+. With a conversion factor around 120μV/h+, the output swing approaching 1V is achieved on the column voltage. The pixel also integrates capacitive deep trench isolation (CDTI) to tackle electrical and optical crosstalk issues. The effective passivation of trench interface by CDTI bias control is demonstrated for a hole-based pixel. As expected, PMOS transistors have much lower trapping noise compared to NMOS counterparts. The PMOS source follower has an average temporal noise of 195μV, mainly dominated by thermal noise contribution.

  5. CMOS Geiger photodiode array with integrated signal processing for imaging of 2D objects using quantum dots

    NASA Astrophysics Data System (ADS)

    Stapels, Christopher J.; Lawrence, William G.; Gurjar, Rajan S.; Johnson, Erik B.; Christian, James F.

    2008-08-01

    Geiger-mode photodiodes (GPD) act as binary photon detectors that convert analog light intensity into digital pulses. Fabrication of arrays of GPD in a CMOS environment simplifies the integration of signal-processing electronics to enhance the performance and provide a low-cost detector-on-a-chip platform. Such an instrument facilitates imaging applications with extremely low light and confined volumes. High sensitivity reading of small samples enables twodimensional imaging of DNA arrays and for tracking single molecules, and observing their dynamic behavior. In this work, we describe the performance of a prototype imaging detector of GPD pixels, with integrated active quenching for use in imaging of 2D objects using fluorescent labels. We demonstrate the integration of on-chip memory and a parallel readout interface for an array of CMOS GPD pixels as progress toward an all-digital detector on a chip. We also describe advances in pixel-level signal processing and solid-state photomultiplier developments.

  6. The ALICE Pixel Detector

    NASA Astrophysics Data System (ADS)

    Mercado-Perez, Jorge

    2002-07-01

    The present document is a brief summary of the performed activities during the 2001 Summer Student Programme at CERN under the Scientific Summer at Foreign Laboratories Program organized by the Particles and Fields Division of the Mexican Physical Society (Sociedad Mexicana de Fisica). In this case, the activities were related with the ALICE Pixel Group of the EP-AIT Division, under the supervision of Jeroen van Hunen, research fellow in this group. First, I give an introduction and overview to the ALICE experiment; followed by a description of wafer probing. A brief summary of the test beam that we had from July 13th to July 25th is given as well.

  7. Measuring the X-ray quantum efficiency of a hybrid CMOS detector with 55Fe

    NASA Astrophysics Data System (ADS)

    Bongiorno, S. D.; Falcone, A. D.; Prieskorn, Z.; Griffith, C.; Burrows, D. N.

    2015-06-01

    Charge coupled devices (CCDs) are currently the workhorse focal plane arrays operating aboard many orbiting astrophysics X-ray telescopes, e.g. Chandra, XMM-Newton, Swift, and Suzaku. In order to meet the count rate, power, and mission duration requirements defined by next-generation X-ray telescopes, future detectors will need to be read out faster, consume less power, and be more resistant to radiation and micrometeoroid damage than current-generation devices. The hybrid CMOS detector (HCD), a type of active pixel sensor, is currently being developed to meet these requirements. With a design architecture that involves bump bonding two semiconductor substrates together at the pixel level, these devices exhibit both the high read speed and low power consumption of CMOS readout circuitry and the high quantum efficiency (QE) of a deeply depleted silicon absorber. These devices are expected to exhibit the same excellent, high-energy quantum efficiency (QE) as deep-depletion CCDs (QE > 0.9 at 6 keV), while at the same time exhibiting superior readout flexibility, power consumption, and radiation hardness than CCDs. In this work we present a QE model for a Teledyne Imaging Sensors HyViSI HCD, which predicts QE=96% at 55Fe source energies (5.89 and 6.49 keV). We then present a QE measurement of the modeled device at the same energies, which shows QE=97±5% and is in good agreement with the model.

  8. Proton-counting radiography for proton therapy: a proof of principle using CMOS APS technology

    PubMed Central

    Poludniowski, G; Allinson, N M; Anaxagoras, T; Esposito, M; Green, S; Manolopoulos, S; Nieto-Camero, J; Parker, D J; Price, T; Evans, P M

    2014-01-01

    Despite the early recognition of the potential of proton imaging to assist proton therapy the modality is still removed from clinical practice, with various approaches in development. For proton-counting radiography applications such as Computed Tomography (CT), the Water-Equivalent-Path-Length (WEPL) that each proton has travelled through an imaged object must be inferred. Typically, scintillator-based technology has been used in various energy/range telescope designs. Here we propose a very different alternative of using radiation-hard CMOS Active Pixel Sensor (APS) technology. The ability of such a sensor to resolve the passage of individual protons in a therapy beam has not been previously shown. Here, such capability is demonstrated using a 36 MeV cyclotron beam (University of Birmingham Cyclotron, Birmingham, UK) and a 200 MeV clinical radiotherapy beam (iThemba LABS, Cape Town, SA). The feasibility of tracking individual protons through multiple CMOS layers is also demonstrated using a two-layer stack of sensors. The chief advantages of this solution are the spatial discrimination of events intrinsic to pixelated sensors, combined with the potential provision of information on both the range and residual energy of a proton. The challenges in developing a practical system are discussed. PMID:24785680

  9. Spark protection layers for CMOS pixel anode chips in MPGDs

    NASA Astrophysics Data System (ADS)

    Bilevych, Y.; Blanco Carballo, V. M.; Chefdeville, M.; Colas, P.; Delagnes, E.; Fransen, M.; van der Graaf, H.; Koppert, W. J. C.; Melai, J.; Salm, C.; Schmitz, J.; Timmermans, J.; Wyrsch, N.

    2011-02-01

    In this work we have investigated the functioning of high resistivity amorphous silicon and silicon-rich nitride layers as a protection against discharges in Micro-Patterned Gaseous Detectors (MPGDs). When the anode is protected by a high resistivity layer, discharge signals are limited in charge. A signal reduction is expected when the layers are too thick; simulations presented in this paper indicate that layers up to 10 μm thick can be applied without significantly degrading the detector performance. Layers of amorphous silicon and silicon-rich nitride have been deposited on top of Timepix and Medipix2 chips in GridPix detectors; with this, chips survive naturally occurring as well as intentionally produced discharges.

  10. Development and simulation results of a sparsification and readout circuit for wide pixel matrices

    NASA Astrophysics Data System (ADS)

    Gabrielli, A.; Giorgi, F.; Morsani, F.; Villa, M.

    2011-06-01

    In future collider experiments, the increasing luminosity and centre of mass energy are rising challenging problems in the design of new inner tracking systems. In this context we develop high-efficiency readout architectures for large binary pixel matrices that are meant to cope with the high-stressing conditions foreseen in the innermost layers of a tracker [The SuperB Conceptual Design Report, INFN/AE-07/02, SLAC-R-856, LAL 07-15, Available online at: http://www.pi.infn.it/SuperB]. We model and design digital readout circuits to be integrated on VLSI ASICs. These architectures can be realized with different technology processes and sensors: they can be implemented on the same silicon sensor substrate of a CMOS MAPS devices (Monolithic Active Pixel Sensor), on the CMOS tier of a hybrid pixel sensor or in a 3D chip where the digital layer is stacked on the sensor and the analog layers [V. Re et al., Nuc. Instr. and Meth. in Phys. Res. A, doi:10.1016/j.nima.2010.05.039]. In the presented work, we consider a data-push architecture designed for a sensor matrix of an area of about 1.3 cm 2 with a pitch of 50 microns. The readout circuit tries to take great advantage of the high density of in-pixel digital logic allowed by vertical integration. We aim at sustaining a rate density of 100 Mtrack ṡ s -1 ṡ cm -2 with a temporal resolution below 1 μs. We show how this architecture can cope with these stressing conditions presenting the results of Monte Carlo simulations.

  11. Fluence measurement of fast neutron fields with a highly efficient recoil proton telescope using active pixel sensors.

    PubMed

    Taforeau, J; Higueret, S; Husson, D; Kachel, M; Lebreton, L

    2014-10-01

    The spectrometer ATHENA (Accurate Telescope for High-Energy Neutron metrology Applications) is being developed at the LNE-IRSN and aims at characterising energy and fluence of fast neutron fields. The detector is a recoil proton telescope and measures neutron fields in the range of 5-20 MeV. This telescope is intended to become a primary standard for both energy and fluence measurements. The neutron detection is achieved by a polyethylene radiator for n-p conversion, three 50-µm-thick silicon sensors that use CMOS technology for proton tracking and a 3-mm-thick silicon diode to measure the residual proton energy. The use of CMOS sensors and silicon diode, owing to a large detection solid angle, increases the intrinsic efficiency of the detector by a factor of 10 compared with conventional designs. The ability of the spectrometer to determine the neutron energy was demonstrated and reported elsewhere. This paper focuses on the fluence measurement of monoenergetic neutron fields in the range of 5-20 MeV. Experimental investigations, performed at the AMANDE facility, indicate a good estimation of neutron fluence at various energies. In addition, a complete description of uncertainties budget is presented in this paper and a Monte Carlo propagation of uncertainty sources leads to a fluence measurement with a precision ∼3-5 % depending on the neutron energy. PMID:24243312

  12. CMOS prototype for retinal prosthesis applications with analog processing

    NASA Astrophysics Data System (ADS)

    Castillo-Cabrera, G.; García-Lamont, J.; Reyes-Barranca, M. A.; Matsumoto-Kuwabara, Y.; Moreno-Cadenas, J. A.; Flores-Nava, L. M.

    2014-12-01

    A core architecture for analog processing, which emulates a retina's receptive field, is presented in this work. A model was partially implemented and built on CMOS standard technology through MOSIS. It considers that the receptive field is the basic unit for image processing in the visual system. That is why the design is concerned on a partial solution of receptive field properties in order to be adapted in the future as an aid to people with retinal diseases. A receptive field is represented by an array of 3×3 pixels. Each pixel carries out a process based on four main operations. This means that image processing is developed at pixel level. Operations involved are: (1) photo-transduction by photocurrent integration, (2) signal averaging from eight neighbouring pixels executed by a neu-NMOS (ν-NMOS) neuron, (3) signal average gradient between central pixel and the average value from the eight neighbouring pixels (this gradient is performed by a comparator) and finally (4) a pulse generator. Each one of these operations gives place to circuital blocks which were built on 0.5 μm CMOS technology.

  13. A CMOS TDI image sensor for Earth observation

    NASA Astrophysics Data System (ADS)

    Rushton, Joseph E.; Stefanov, Konstantin D.; Holland, Andrew D.; Endicott, James; Mayer, Frederic; Barbier, Frederic

    2015-09-01

    Time Delay and Integration (TDI) is used to increase the Signal to Noise Ratio (SNR) in image sensors when imaging fast moving objects. One important TDI application is in Earth observation from space. In order to operate in the space radiation environment, the effect that radiation damage has on the performance of the image sensors must be understood. This work looks at prototype TDI sensor pixel designs, produced by e2v technologies. The sensor is a CCD-like charge transfer device, allowing in-pixel charge summation, produced on a CMOS process. The use of a CMOS process allows potential advantages such as lower power consumption, smaller pixels, higher line rate and extra on-chip functionality which can simplify system design. CMOS also allows a dedicated output amplifier per column allowing fewer charge transfers and helping to facilitate higher line rates than CCDs. In this work the effect on the pixels of radiation damage from high energy protons, at doses relevant to a low Earth orbit mission, is presented. This includes the resulting changes in Charge Transfer inefficiency (CTI) and dark signal.

  14. Polycrystalline Mercuric Iodide Films on CMOS Readout Arrays

    PubMed Central

    Hartsough, Neal E.; Iwanczyk, Jan S.; Nygard, Einar; Malakhov, Nail; Barber, William C.; Gandhi, Thulasidharan

    2009-01-01

    We have created high-resolution x-ray imaging devices using polycrystalline mercuric iodide (HgI2) films grown directly onto CMOS readout chips using a thermal vapor transport process. Images from prototype 400×400 pixel HgI2-coated CMOS readout chips are presented, where the pixel grid is 30 μm × 30 μm. The devices exhibited sensitivity of 6.2 μC/Rcm2 with corresponding dark current of ∼2.7 nA/cm2, and a 80 μm FWHM planar image response to a 50 μm slit aperture. X-ray CT images demonstrate a point spread function sufficient to obtain a 50 μm spatial resolution in reconstructed CT images at a substantially reduced dose compared to phosphor-coated readouts. The use of CMOS technology allows for small pixels (30 μm), fast readout speeds (8 fps for a 3200×3200 pixel array), and future design flexibility due to the use of well-developed fabrication processes. PMID:20161098

  15. Single photon counting pixel detectors for synchrotron radiation experiments

    NASA Astrophysics Data System (ADS)

    Toyokawa, H.; Broennimann, Ch.; Eikenberry, E. F.; Henrich, B.; Kawase, M.; Kobas, M.; Kraft, P.; Sato, M.; Schmitt, B.; Suzuki, M.; Tanida, H.; Uruga, T.

    2010-11-01

    At the Paul Scherrer Institute PSI an X-ray single photon counting pixel detector (PILATUS) based on the hybrid-pixel detector technology was developed in collaboration with SPring-8. The detection element is a 320 or 450 μm thick silicon sensor forming pixelated pn-diodes with a pitch of 172 μm×172 μm. An array of 2×8 custom CMOS readout chips are indium bump-bonded to the sensor, which leads to 33.5 mm×83.8 mm detective area. Each pixel contains a charge-sensitive amplifier, a single level discriminator and a 20 bit counter. This design realizes a high dynamic range, short readout time of less than 3 ms, a high framing rate of over 200 images per second and an excellent point-spread function. The maximum counting rate achieves more than 2×10 6 X-rays/s/pixel.

  16. Mapping Electrical Crosstalk in Pixelated Sensor Arrays

    NASA Technical Reports Server (NTRS)

    Seshadri, S.; Cole, D. M.; Hancock, B. R.; Smith, R. M.

    2008-01-01

    Electronic coupling effects such as Inter-Pixel Capacitance (IPC) affect the quantitative interpretation of image data from CMOS, hybrid visible and infrared imagers alike. Existing methods of characterizing IPC do not provide a map of the spatial variation of IPC over all pixels. We demonstrate a deterministic method that provides a direct quantitative map of the crosstalk across an imager. The approach requires only the ability to reset single pixels to an arbitrary voltage, different from the rest of the imager. No illumination source is required. Mapping IPC independently for each pixel is also made practical by the greater S/N ratio achievable for an electrical stimulus than for an optical stimulus, which is subject to both Poisson statistics and diffusion effects of photo-generated charge. The data we present illustrates a more complex picture of IPC in Teledyne HgCdTe and HyViSi focal plane arrays than is presently understood, including the presence of a newly discovered, long range IPC in the HyViSi FPA that extends tens of pixels in distance, likely stemming from extended field effects in the fully depleted substrate. The sensitivity of the measurement approach has been shown to be good enough to distinguish spatial structure in IPC of the order of 0.1%.

  17. On-chip polarizer on image sensor using advanced CMOS technology

    NASA Astrophysics Data System (ADS)

    Sasagawa, Kiyotaka; Wakama, Norimitsu; Noda, Toshihiko; Tokuda, Takashi; Kakiuchi, Kiyomi; Ohta, Jun

    2014-03-01

    The structures in advanced complementary metal-oxide-semiconductor (CMOS) integrated circuit technology are in the range of deep-submicron. It allows designing and integrating nano-photonic structures for the visible to near infrared region on a chip. In this work, we designed and fabricated an image sensor with on-pixel metal wire grid polarizers by using a 65-nm standard CMOS technology. It is known that the extinction ratio of a metal wire grid polarizer is increased with decrease in the grid pitch. With the metal wire layers of the 65-nm technology, the grid pitch sufficiently smaller than the wavelengths of visible light can be realized. The extinction ratio of approximately 20 dB has been successfully achieved at a wavelength of 750 nm. In the CMOS technologies, it is usual to include multiple metal layers. This feature is also useful to increase the extinction ratio of polarizers. We designed dual layer polarizers. Each layer partially reflects incident light. Thus, the layers form a cavity and its transmission spectrum depends on the layer position. The extinction ratio of 19.2 dB at 780 nm was achieved with the grid pitch greater than the single layer polarizer. The high extinction ratio is obtained only red to near infrared region because the fine metal layers of deepsubmicron standard CMOS process is usually composed of Cu. Thus, it should be applied for measurement or observation where wide spectrum is not required such as optical rotation measurement of optically active materials or electro-optic imaging of RF/THz wave.

  18. Monolithic CMOS imaging x-ray spectrometers

    NASA Astrophysics Data System (ADS)

    Kenter, Almus; Kraft, Ralph; Gauron, Thomas; Murray, Stephen S.

    2014-07-01

    The Smithsonian Astrophysical Observatory (SAO) in collaboration with SRI/Sarnoff is developing monolithic CMOS detectors optimized for x-ray astronomy. The goal of this multi-year program is to produce CMOS x-ray imaging spectrometers that are Fano noise limited over the 0.1-10keV energy band while incorporating the many benefits of CMOS technology. These benefits include: low power consumption, radiation "hardness", high levels of integration, and very high read rates. Small format test devices from a previous wafer fabrication run (2011-2012) have recently been back-thinned and tested for response below 1keV. These devices perform as expected in regards to dark current, read noise, spectral response and Quantum Efficiency (QE). We demonstrate that running these devices at rates ~> 1Mpix/second eliminates the need for cooling as shot noise from any dark current is greatly mitigated. The test devices were fabricated on 15μm, high resistivity custom (~30kΩ-cm) epitaxial silicon and have a 16 by 192 pixel format. They incorporate 16μm pitch, 6 Transistor Pinned Photo Diode (6TPPD) pixels which have ~40μV/electron sensitivity and a highly parallel analog CDS signal chain. Newer, improved, lower noise detectors have just been fabricated (October 2013). These new detectors are fabricated on 9μm epitaxial silicon and have a 1k by 1k format. They incorporate similar 16μm pitch, 6TPPD pixels but have ~ 50% higher sensitivity and much (3×) lower read noise. These new detectors have undergone preliminary testing for functionality in Front Illuminated (FI) form and are presently being prepared for back thinning and packaging. Monolithic CMOS devices such as these, would be ideal candidate detectors for the focal planes of Solar, planetary and other space-borne x-ray astronomy missions. The high through-put, low noise and excellent low energy response, provide high dynamic range and good time resolution; bright, time varying x-ray features could be temporally and

  19. Towards arrays of smart-pixels for time-correlated single photon counting and time of flight application

    NASA Astrophysics Data System (ADS)

    Markovic, Bojan; Tisa, Simone; Tosi, Alberto; Zappa, Franco

    2011-01-01

    We present a novel "smart-pixel" able to detect single photons and to measure and record in-pixel the time delay between a START pulse (e.g., laser excitation, cell stimulus, or LIDAR flash) and a STOP pulse given by the detection of a single photon (e. g., fluorescence decay signal or back reflection from an object). This smart-pixel represents the basic building block of SPAD arrays aimed at time-correlated single photon counting (TCSPC) applications (like FLIM, FCS, FRET), but also at photon timing and direct Time-of-Flight (dTOF) measurements for 3D ranging applications (e.g., in LIDAR systems). The pixel comprises a Single-Photon Avalanche Diode (SPAD) detector, an analog sensing and driving electronics, and a Time-to-Digital Converter monolithically designed and manufactured into the same chip. We report on the design and characterization of prototype circuits, fabricated in a 0.35 μm standard CMOS technology containing complete conversion channels, smart-pixels and ancillary electronics with 20 μm active area diameter SPAD detectors and related quenching circuitry. With a 100 MHz reference clock, the TDC provides a time-resolution of 10 ps, a dynamic range of 160 ns and very high conversion linearity.

  20. Spectrometer with CMOS demodulation of fiber optic Bragg grating sensors

    NASA Astrophysics Data System (ADS)

    Christiansen, Martin Brokner

    A CMOS imager based spectrometer is developed to interrogate a network containing a large number of Bragg grating sensors. The spectrometer uses a Prism-Grating- Prism (PGP) to spectrally separate serially multiplexed Bragg reflections on a single fiber. As a result, each Bragg grating produces a discrete spot on the CMOS imager that shifts horizontally as the Bragg grating experiences changes in strain or temperature. The reflected wavelength of the spot can be determined by finding the center of the spot produced. The use of a randomly addressable CMOS imager enables a flexible sampling rate. Some fibers can be interrogated at a high sampling rate while others can be interrogated at a low sampling rate. However, the use of a CMOS imager leads to several unique problems in terms of signal processing. These include a logarithmic pixel response, a low signal-to-noise ratio, a long pixel time constant, and software issues. The expected capabilities of the CMOS imager based spectrometer are determined with a theoretical model. The theoretical model tests three algorithms for determining the center of the spot: single row centroid, single row parabolic fit, and entire spot centroid. The theoretical results are compared to laboratory test data and field test data. The CMOS based spectrometer is capable of interrogating many optical fibers, and in the configuration tested, the fiber bundle consisted of 23 fibers. Using this system, a single fiber can be interrogated from 778 nm to 852 nm at 2100 Hz or multiple fibers can be interrogated over the same wavelength so that the total number of fiber interrogations is up to 2100 per second. The reflected Bragg wavelength can be determined within +/-3pm, corresponding to a +/-3μɛ uncertainty.

  1. Fundamental performance differences between CMOS and CCD imagers: Part II

    NASA Astrophysics Data System (ADS)

    Janesick, James; Andrews, James; Tower, John; Grygon, Mark; Elliott, Tom; Cheng, John; Lesser, Michael; Pinter, Jeff

    2007-09-01

    A new class of CMOS imagers that compete with scientific CCDs is presented. The sensors are based on deep depletion backside illuminated technology to achieve high near infrared quantum efficiency and low pixel cross-talk. The imagers deliver very low read noise suitable for single photon counting - Fano-noise limited soft x-ray applications. Digital correlated double sampling signal processing necessary to achieve low read noise performance is analyzed and demonstrated for CMOS use. Detailed experimental data products generated by different pixel architectures (notably 3TPPD, 5TPPD and 6TPG designs) are presented including read noise, charge capacity, dynamic range, quantum efficiency, charge collection and transfer efficiency and dark current generation. Radiation damage data taken for the imagers is also reported.

  2. A CMOS image sensor dedicated to medical gamma camera application

    NASA Astrophysics Data System (ADS)

    Salahuddin, Nur S.; Paindavoine, Michel; Ginhac, Dominique; Parmentier, Michel; Tamda, Najia

    2005-03-01

    Generally, medical Gamma Camera are based on the Anger principle. These cameras use a scintillator block coupled to a bulky array of photomultiplier tube (PMT). To simplify this, we designed a new integrated CMOS image sensor in order to replace bulky PMT photodetetors. We studied several photodiodes sensors including current mirror amplifiers. These photodiodes have been fabricated using a CMOS 0.6 micrometers process from Austria Mikro Systeme (AMS). Each sensor pixel in the array occupies respectively, 1mm x 1mm area, 0.5mm x 0.5mm area and 0.2mm 0.2mm area with fill factor 98 % and total chip area is 2 square millimeters. The sensor pixels show a logarithmic response in illumination and are capable of detecting very low green light emitting diode (less than 0.5 lux) . These results allow to use our sensor in new Gamma Camera solid-state concept.

  3. A back-illuminated megapixel CMOS image sensor

    NASA Technical Reports Server (NTRS)

    Pain, Bedabrata; Cunningham, Thomas; Nikzad, Shouleh; Hoenk, Michael; Jones, Todd; Wrigley, Chris; Hancock, Bruce

    2005-01-01

    In this paper, we present the test and characterization results for a back-illuminated megapixel CMOS imager. The imager pixel consists of a standard junction photodiode coupled to a three transistor-per-pixel switched source-follower readout [1]. The imager also consists of integrated timing and control and bias generation circuits, and provides analog output. The analog column-scan circuits were implemented in such a way that the imager could be configured to run in off-chip correlated double-sampling (CDS) mode. The imager was originally designed for normal front-illuminated operation, and was fabricated in a commercially available 0.5 pn triple-metal CMOS-imager compatible process. For backside illumination, the imager was thinned by etching away the substrate was etched away in a post-fabrication processing step.

  4. Ion traps fabricated in a CMOS foundry

    SciTech Connect

    Mehta, K. K.; Ram, R. J.; Eltony, A. M.; Chuang, I. L.; Bruzewicz, C. D.; Sage, J. M. Chiaverini, J.

    2014-07-28

    We demonstrate trapping in a surface-electrode ion trap fabricated in a 90-nm CMOS (complementary metal-oxide-semiconductor) foundry process utilizing the top metal layer of the process for the trap electrodes. The process includes doped active regions and metal interconnect layers, allowing for co-fabrication of standard CMOS circuitry as well as devices for optical control and measurement. With one of the interconnect layers defining a ground plane between the trap electrode layer and the p-type doped silicon substrate, ion loading is robust and trapping is stable. We measure a motional heating rate comparable to those seen in surface-electrode traps of similar size. This demonstration of scalable quantum computing hardware utilizing a commercial CMOS process opens the door to integration and co-fabrication of electronics and photonics for large-scale quantum processing in trapped-ion arrays.

  5. Amorphous In–Ga–Zn–O thin-film transistor active pixel sensor x-ray imager for digital breast tomosynthesis

    SciTech Connect

    Zhao, Chumin; Kanicki, Jerzy

    2014-09-15

    Purpose: The breast cancer detection rate for digital breast tomosynthesis (DBT) is limited by the x-ray image quality. The limiting Nyquist frequency for current DBT systems is around 5 lp/mm, while the fine image details contained in the high spatial frequency region (>5 lp/mm) are lost. Also today the tomosynthesis patient dose is high (0.67–3.52 mGy). To address current issues, in this paper, for the first time, a high-resolution low-dose organic photodetector/amorphous In–Ga–Zn–O thin-film transistor (a-IGZO TFT) active pixel sensor (APS) x-ray imager is proposed for next generation DBT systems. Methods: The indirect x-ray detector is based on a combination of a novel low-cost organic photodiode (OPD) and a cesium iodide-based (CsI:Tl) scintillator. The proposed APS x-ray imager overcomes the difficulty of weak signal detection, when small pixel size and low exposure conditions are used, by an on-pixel signal amplification with a significant charge gain. The electrical performance of a-IGZO TFT APS pixel circuit is investigated by SPICE simulation using modified Rensselaer Polytechnic Institute amorphous silicon (a-Si:H) TFT model. Finally, the noise, detective quantum efficiency (DQE), and resolvability of the complete system are modeled using the cascaded system formalism. Results: The result demonstrates that a large charge gain of 31–122 is achieved for the proposed high-mobility (5–20 cm{sup 2}/V s) amorphous metal-oxide TFT APS. The charge gain is sufficient to eliminate the TFT thermal noise, flicker noise as well as the external readout circuit noise. Moreover, the low TFT (<10{sup −13} A) and OPD (<10{sup −8} A/cm{sup 2}) leakage currents can further reduce the APS noise. Cascaded system analysis shows that the proposed APS imager with a 75 μm pixel pitch can effectively resolve the Nyquist frequency of 6.67 lp/mm, which can be further improved to ∼10 lp/mm if the pixel pitch is reduced to 50 μm. Moreover, the

  6. Implantable CMOS Biomedical Devices

    PubMed Central

    Ohta, Jun; Tokuda, Takashi; Sasagawa, Kiyotaka; Noda, Toshihiko

    2009-01-01

    The results of recent research on our implantable CMOS biomedical devices are reviewed. Topics include retinal prosthesis devices and deep-brain implantation devices for small animals. Fundamental device structures and characteristics as well as in vivo experiments are presented. PMID:22291554

  7. Digital-pixel focal plane array development

    NASA Astrophysics Data System (ADS)

    Brown, Matthew G.; Baker, Justin; Colonero, Curtis; Costa, Joe; Gardner, Tom; Kelly, Mike; Schultz, Ken; Tyrrell, Brian; Wey, Jim

    2010-01-01

    Since 2006, MIT Lincoln Laboratory has been developing Digital-pixel Focal Plane Array (DFPA) readout integrated circuits (ROICs). To date, four 256 × 256 30 μm pitch DFPA designs with in-pixel analog to digital conversion have been fabricated using IBM 90 nm CMOS processes. The DFPA ROICs are compatible with a wide range of detector materials and cutoff wavelengths; HgCdTe, QWIP, and InGaAs photo-detectors with cutoff wavelengths ranging from 1.6 to 14.5 μm have been hybridized to the same digital-pixel readout. The digital-pixel readout architecture offers high dynamic range, A/C or D/C coupled integration, and on-chip image processing with low power orthogonal transfer operations. The newest ROIC designs support two-color operation with a single Indium bump connection. Development and characterization of the two-color DFPA designs is presented along with applications for this new digital readout technology.

  8. On noise in time-delay integration CMOS image sensors

    NASA Astrophysics Data System (ADS)

    Levski, Deyan; Choubey, Bhaskar

    2016-05-01

    Time delay integration sensors are of increasing interest in CMOS processes owing to their low cost, power and ability to integrate with other circuit readout blocks. This paper presents an analysis of the noise contributors in current day CMOS Time-Delay-Integration image sensors with various readout architectures. An analysis of charge versus voltage domain readout modes is presented, followed by a noise classification of the existing Analog Accumulator Readout (AAR) and Digital Accumulator Readout (DAR) schemes for TDI imaging. The analysis and classification of existing readout schemes include, pipelined charge transfer, buffered direct injection, voltage as well as current-mode analog accumulators and all-digital accumulator techniques. Time-Delay-Integration imaging modes in CMOS processes typically use an N-number of readout steps, equivalent to the number of TDI pixel stages. In CMOS TDI sensors, where voltage domain readout is used, the requirements over speed and noise of the ADC readout chain are increased due to accumulation of the dominant voltage readout and ADC noise with every stage N. Until this day, the latter is the primary reason for a leap-back of CMOS TDI sensors as compared to their CCD counterparts. Moreover, most commercial CMOS TDI implementations are still based on a charge-domain readout, mimicking a CCD-like operation mode. Thus, having a good understanding of each noise contributor in the signal chain, as well as its magnitude in different readout architectures, is vital for the design of future generation low-noise CMOS TDI image sensors based on a voltage domain readout. This paper gives a quantitative classification of all major noise sources for all popular implementations in the literature.

  9. Evaluation of MOBILE-based gate-level pipelining augmenting CMOS with RTDs

    NASA Astrophysics Data System (ADS)

    Nuñez, Juan; Avedillo, María J.; Quintana, José M.

    2011-05-01

    The incorporation of Resonant Tunnel Diodes (RTDs) into III/V transistor technologies has shown an improved circuit performance: higher circuit speed, reduced component count, and/or lowered power consumption. Currently, the incorporation of these devices into CMOS technologies (RTD-CMOS) is an area of active research. Although some works have focused the evaluation of the advantages of this incorporation, additional work in this direction is required. We compare RTD-CMOS and pure CMOS realizations of a network of logic gates which can be operated in a gate-level pipeline. Significant lower average power is obtained for RTD-CMOS implementations.

  10. FPIX2: A radiation-hard pixel readout chip for BTeV

    SciTech Connect

    David C. Christian et al.

    2000-12-11

    A radiation-hard pixel readout chip, FPIX2, is being developed at Fermilab for the recently approved BTeV experiment. Although designed for BTeV, this chip should also be appropriate for use by CDF and DZero. A short review of this development effort is presented. Particular attention is given to the circuit redesign which was made necessary by the decision to implement FPIX2 using a standard deep-submicron CMOS process rather than an explicitly radiation-hard CMOS technology, as originally planned. The results of initial tests of prototype 0.25{micro} CMOS devices are presented, as are plans for the balance of the development effort.

  11. Current progress on pixel level packaging for uncooled IRFPA

    NASA Astrophysics Data System (ADS)

    Dumont, G.; Rabaud, W.; Yon, J.-J.; Carle, L.; Goudon, V.; Vialle, C.; Becker, Sébastien; Hamelin, Antoine; Arnaud, A.

    2012-06-01

    Vacuum packaging is definitely a major cost driver for uncooled IRFPA and a technological breakthrough is still expected to comply with the very low cost infrared camera market. To address this key issue, CEA-LETI is developing a Pixel Level Packaging (PLP) technology which basically consists in capping each pixel under vacuum in the direct continuation of the wafer level bolometer process. Previous CEA-LETI works have yet shown the feasibility of PLP based microbolometers that exhibit the required thermal insulation and vacuum achievement. CEA-LETI is still pushing the technology which has been now applied for the first time on a CMOS readout circuit. The paper will report on the recent progress obtained on PLP technology with particular emphasis on the optical efficiency of the PLP arrangement compared to the traditional microbolometer packaging. Results including optical performances, aging studies and compatibility with CMOS readout circuit are extensively presented.

  12. Combined reactor neutron beam and {sup 60}Co γ-ray radiation effects on CMOS APS image sensors

    SciTech Connect

    Wang, Zujun Chen, Wei; Sheng, Jiangkun; Liu, Yan; Xiao, Zhigang; Huang, Shaoyan; Liu, Minbo

    2015-02-15

    The combined reactor neutron beam and {sup 60}Co γ-ray radiation effects on complementary metal-oxide semiconductor (CMOS) active pixel sensors (APS) have been discussed and some new experimental phenomena are presented. The samples are manufactured in the standard 0.35-μm CMOS technology. Two samples were first exposed to {sup 60}Co γ-rays up to the total ionizing dose (TID) level of 200 krad(Si) at the dose rates of 50.0 and 0.2 rad(Si)/s, and then exposed to neutron fluence up to 1 × 10{sup 11} n/cm{sup 2} (1-MeV equivalent neutron fluence). One sample was first exposed to neutron fluence up to 1 × 10{sup 11} n/cm{sup 2} (1-MeV equivalent neutron fluence), and then exposed to {sup 60}Co γ-rays up to the TID level of 200 krad(Si) at the dose rate of 0.2 rad(Si)/s. The mean dark signal (K{sub D}), the dark signal non-uniformity (DSNU), and the noise (V{sub N}) versus the total dose and neutron fluence has been investigated. The degradation mechanisms of CMOS APS image sensors have been analyzed, especially for the interaction induced by neutron displacement damage and TID damage.

  13. PixelLearn

    NASA Technical Reports Server (NTRS)

    Mazzoni, Dominic; Wagstaff, Kiri; Bornstein, Benjamin; Tang, Nghia; Roden, Joseph

    2006-01-01

    PixelLearn is an integrated user-interface computer program for classifying pixels in scientific images. Heretofore, training a machine-learning algorithm to classify pixels in images has been tedious and difficult. PixelLearn provides a graphical user interface that makes it faster and more intuitive, leading to more interactive exploration of image data sets. PixelLearn also provides image-enhancement controls to make it easier to see subtle details in images. PixelLearn opens images or sets of images in a variety of common scientific file formats and enables the user to interact with several supervised or unsupervised machine-learning pixel-classifying algorithms while the user continues to browse through the images. The machinelearning algorithms in PixelLearn use advanced clustering and classification methods that enable accuracy much higher than is achievable by most other software previously available for this purpose. PixelLearn is written in portable C++ and runs natively on computers running Linux, Windows, or Mac OS X.

  14. A CMOS vision chip for a contrast-enhanced image using a logarithmic APS and a switch-selective resistive network

    NASA Astrophysics Data System (ADS)

    Kong, Jae-Sung; Kim, Sang-Heon; Sung, Dong-Kyu; Seo, Sang-Ho; Shin, Jang-Kyoo

    2007-02-01

    In this paper, a vision chip for a contrast-enhanced image based on a structure of a biological retina is introduced. The key advantage of this structure is high speed of signal processing. In a conventional active pixel sensor (APS), the charge accumulation time limits its operation speed. In order to enhance the speed, a logarithmic APS was applied to the vision chip. By applying a MOS-type photodetector to the logarithmic APS, we could achieve sufficient output swing for the vision chip in natural illumination condition. In addition, a CMOS buffer circuit, a common drain amplifier, is commonly used for both raw and smoothed images by using additional switches. By using the switch-selective resistive network, the total number of MOSFETs for a unit pixel and the fixed-pattern noise were reduced. A vision chip with a 160×120 pixel array was fabricated using a 0.35 μm double-poly four-metal CMOS technology, and its operation was experimentally investigated.

  15. High resolution, high bandwidth global shutter CMOS area scan sensors

    NASA Astrophysics Data System (ADS)

    Faramarzpour, Naser; Sonder, Matthias; Li, Binqiao

    2013-10-01

    Global shuttering, sometimes also known as electronic shuttering, enables the use of CMOS sensors in a vast range of applications. Teledyne DALSA Global shutter sensors are able to integrate light synchronously across millions of pixels with microsecond accuracy. Teledyne DALSA offers 5 transistor global shutter pixels in variety of resolutions, pitches and noise and full-well combinations. One of the recent generations of these pixels is implemented in 12 mega pixel area scan device at 6 um pitch and that images up to 70 frames per second with 58 dB dynamic range. These square pixels include microlens and optional color filters. These sensors also offer exposure control, anti-blooming and high dynamic range operation by introduction of a drain and a PPD reset gate to the pixel. The state of the art sense node design of Teledyne DALSA's 5T pixel offers exceptional shutter rejection ratio. The architecture is consistent with the requirements to use stitching to achieve very large area scan devices. Parallel or serial digital output is provided on these sensors using on-chip, column-wise analog to digital converters. Flexible ADC bit depth combined with windowing (adjustable region of interest, ROI) allows these sensors to run with variety of resolution/bandwidth combinations. The low power, state of the art LVDS I/O technology allows for overall power consumptions of less than 2W at full performance conditions.

  16. A high-speed CMOS image sensor with column-parallel single capacitor CDSs and single-slope ADCs

    NASA Astrophysics Data System (ADS)

    Li, Quanliang; Shi, Cong; Wu, Nanjian

    2011-08-01

    This paper presents a high speed CMOS image sensor (CIS) with column-parallel single capacitor correlated double samplings (CDSs), programmable gain amplifiers (PGAs) and single-slope analog-to-digital converters (ADCs). The single capacitor CDS circuit has only one capacitor so that the area CDS circuit is small. In order to attain appropriate image contrast under different light conditions, the signal range can be adjusted by PGA. Single-slope ADC has smaller chip area than others ADCs and is suitable for column-parallel CIS architectures. A prototype sensor of 256x256 pixels was realized in a 0.13μm 1P3M CIS process. Its pixel circuit is 4T active pixel sensor (APS) and pixel size is 10x10μm2. Total chip area is 4x4mm2. The prototype achieves the full frame rate in excess of 250 frames per second, the sensitivity of 10.7V/lx•s, the conversion gain of 55.6μV/e and the column-to- column fixed-pattern noise (FPN) 0.41%.

  17. Digital pixel readout integrated circuit architectures for LWIR

    NASA Astrophysics Data System (ADS)

    Shafique, Atia; Yazici, Melik; Kayahan, Huseyin; Ceylan, Omer; Gurbuz, Yasar

    2015-06-01

    This paper presents and discusses digital pixel readout integrated circuit architectures for long wavelength infrared (LWIR) in CMOS technology. Presented architectures are designed for scanning and staring arrays type detectors respectively. For scanning arrays, digital time delay integration (TDI) is implemented on 8 pixels with sampling rate up to 3 using CMOS 180nm technology. Input referred noise of ROIC is below 750 rms electron meanwhile power dissipation is appreciably under 30mW. ROIC design is optimized to perform at room as well as cryogenic temperatures. For staring type arrays, a digital pixel architecture relying on coarse quantization with pulse frequency modulation (PFM) and novel approach of extended integration is presented. It can achieve extreme charge handling capacity of 2.04Ge- with 20 bit output resolution and power dissipation below 350 nW in CMOS 90nm technology. Efficient mechanism of measuring the time to estimate the remaining charge on integration capacitor in order to achieve low SNR has employed.

  18. Fully integrated system-on-chip for pixel-based 3D depth and scene mapping

    NASA Astrophysics Data System (ADS)

    Popp, Martin; De Coi, Beat; Thalmann, Markus; Gancarz, Radoslav; Ferrat, Pascal; Dürmüller, Martin; Britt, Florian; Annese, Marco; Ledergerber, Markus; Catregn, Gion-Pol

    2012-03-01

    We present for the first time a fully integrated system-on-chip (SoC) for pixel-based 3D range detection suited for commercial applications. It is based on the time-of-flight (ToF) principle, i.e. measuring the phase difference of a reflected pulse train. The product epc600 is fabricated using a dedicated process flow, called Espros Photonic CMOS. This integration makes it possible to achieve a Quantum Efficiency (QE) of >80% in the full wavelength band from 520nm up to 900nm as well as very high timing precision in the sub-ns range which is needed for exact detection of the phase delay. The SoC features 8x8 pixels and includes all necessary sub-components such as ToF pixel array, voltage generation and regulation, non-volatile memory for configuration, LED driver for active illumination, digital SPI interface for easy communication, column based 12bit ADC converters, PLL and digital data processing with temporary data storage. The system can be operated at up to 100 frames per second.

  19. Fully digital pixel readout architecture with a current-mode A/D converter

    NASA Astrophysics Data System (ADS)

    Eshraghian, Kamran; Lachowicz, Stefan W.

    2001-11-01

    Camera-on-a-CMOS chip will be an inevitable component of future intelligent vision systems. However, up till now, the dominant format of data in imaging devices is still analog. The analog photocurrent or sampled voltage is transferred to the ADC via a column or a column/row bus. Moreover, in the active pixel configuration the area occupied by circuitry reduces significantly the fill factor, so that there are heavy constraints imposed on the size of the circuits used. In this paper a concept of back illuminated focal plane is presented. The system consists of two chips bonded face to face using Indium bumps. The top chip, which is the seeing chip, is thinned and the light signal is applied to the bottom surface. The bottom chip is the processing chip and it contains a distributed array of analog-to digital converters. As the seeing chip is fully dedicated to photosensors the fill factor can be increased from 25-40% possible on a single plane to over 95% with two planes. The analog-to-digital converters are algorithmic current-mode converters, where one-bit cell is implemented in the processing area facing one-pixel. Eight such cells are cascaded to form an 8-bit converter. As a result, a fully digital pixel readout is obtained.

  20. Fibre-optic coupling to high-resolution CCD and CMOS image sensors

    NASA Astrophysics Data System (ADS)

    van Silfhout, R. G.; Kachatkou, A. S.

    2008-12-01

    We describe a simple method of gluing fibre-optic faceplates to complementary metal oxide semiconductor (CMOS) active pixel and charge coupled device (CCD) image sensors and report on their performance. Cross-sectional cuts reveal that the bonding layer has a thickness close to the diameter of the individual fibres and is uniform over the whole sensor area. Our method requires no special tools or alignment equipment and gives reproducible and high-quality results. The method maintains a uniform bond layer thickness even if sensor dies are mounted at slight angles with their package. These fibre-coupled sensors are of particular interest to X-ray imaging applications but also provide a solution for compact optical imaging systems.

  1. Focal-plane CMOS wavelet feature extraction for real-time pattern recognition

    NASA Astrophysics Data System (ADS)

    Olyaei, Ashkan; Genov, Roman

    2005-09-01

    Kernel-based pattern recognition paradigms such as support vector machines (SVM) require computationally intensive feature extraction methods for high-performance real-time object detection in video. The CMOS sensory parallel processor architecture presented here computes delta-sigma (ΔΣ)-modulated Haar wavelet transform on the focal plane in real time. The active pixel array is integrated with a bank of column-parallel first-order incremental oversampling analog-to-digital converters (ADCs). Each ADC performs distributed spatial focal-plane sampling and concurrent weighted average quantization. The architecture is benchmarked in SVM face detection on the MIT CBCL data set. At 90% detection rate, first-level Haar wavelet feature extraction yields a 7.9% reduction in the number of false positives when compared to classification with no feature extraction. The architecture yields 1.4 GMACS simulated computational throughput at SVGA imager resolution at 8-bit output depth.

  2. A 75-ps Gated CMOS Image Sensor with Low Parasitic Light Sensitivity

    PubMed Central

    Zhang, Fan; Niu, Hanben

    2016-01-01

    In this study, a 40 × 48 pixel global shutter complementary metal-oxide-semiconductor (CMOS) image sensor with an adjustable shutter time as low as 75 ps was implemented using a 0.5-μm mixed-signal CMOS process. The implementation consisted of a continuous contact ring around each p+/n-well photodiode in the pixel array in order to apply sufficient light shielding. The parasitic light sensitivity of the in-pixel storage node was measured to be 1/8.5 × 107 when illuminated by a 405-nm diode laser and 1/1.4 × 104 when illuminated by a 650-nm diode laser. The pixel pitch was 24 μm, the size of the square p+/n-well photodiode in each pixel was 7 μm per side, the measured random readout noise was 217 e− rms, and the measured dynamic range of the pixel of the designed chip was 5500:1. The type of gated CMOS image sensor (CIS) that is proposed here can be used in ultra-fast framing cameras to observe non-repeatable fast-evolving phenomena. PMID:27367699

  3. SNR improvement for hyperspectral application using frame and pixel binning

    NASA Astrophysics Data System (ADS)

    Rehman, Sami Ur; Kumar, Ankush; Banerjee, Arup

    2016-05-01

    Hyperspectral imaging spectrometer systems are increasingly being used in the field of remote sensing for variety of civilian and military applications. The ability of such instruments in discriminating finer spectral features along with improved spatial and radiometric performance have made such instruments a powerful tool in the field of remote sensing. Design and development of spaceborne hyper spectral imaging spectrometers poses lot of technological challenges in terms of optics, dispersion element, detectors, electronics and mechanical systems. The main factors that define the type of detectors are the spectral region, SNR, dynamic range, pixel size, number of pixels, frame rate, operating temperature etc. Detectors with higher quantum efficiency and higher well depth are the preferred choice for such applications. CCD based Si detectors serves the requirement of high well depth for VNIR band spectrometers but suffers from smear. Smear can be controlled by using CMOS detectors. Si CMOS detectors with large format arrays are available. These detectors generally have smaller pitch and low well depth. Binning technique can be used with available CMOS detectors to meet the large swath, higher resolution and high SNR requirements. Availability of larger dwell time of satellite can be used to bin multiple frames to increase the signal collection even with lesser well depth detectors and ultimately increase the SNR. Lab measurements reveal that SNR improvement by frame binning is more in comparison to pixel binning. Effect of pixel binning as compared to the frame binning will be discussed and degradation of SNR as compared to theoretical value for pixel binning will be analyzed.

  4. Smart pixel technology and an application to two-dimensional analog-to-digital conversion

    NASA Astrophysics Data System (ADS)

    Shoop, Barry L.; Sadowski, Robert W.; Dudevoir, Glen P.; Ressler, Eugene K.; Sayles, Andre H.; Hall, Dirk A.; Litynski, Daniel M.

    1998-12-01

    A short review of smart pixel technology is followed by an application of one specific smart pixel technology to a 2D application of analog-to-digital conversion called digital image halftoning. A novel approach to digital image halftoning is described based on a symmetric error diffusion algorithm, a new form of artificial neural network called an error diffusion neural network, and a smart pixel optoelectronic architecture. Two generations of smart pixel architectures are described that incorporate self-electro- optic effect device (SEED) modulators flip-chip bonded to submicrometer feature size complementary metal-oxide semiconductor (CMOS) silicon circuitry to produce CMOS-SEED implementations of the error diffusion neural network. Simulations and experimental characterizations demonstrate that this hardware approach provides sufficient computational accuracy for the analog neural network while simultaneously providing switching speeds that support halftoning at video rates.

  5. Sub-pixel mapping of water boundaries using pixel swapping algorithm (case study: Tagliamento River, Italy)

    NASA Astrophysics Data System (ADS)

    Niroumand-Jadidi, Milad; Vitti, Alfonso

    2015-10-01

    Taking the advantages of remotely sensed data for mapping and monitoring of water boundaries is of particular importance in many different management and conservation activities. Imagery data are classified using automatic techniques to produce maps entering the water bodies' analysis chain in several and different points. Very commonly, medium or coarse spatial resolution imagery is used in studies of large water bodies. Data of this kind is affected by the presence of mixed pixels leading to very outstanding problems, in particular when dealing with boundary pixels. A considerable amount of uncertainty inescapably occurs when conventional hard classifiers (e.g., maximum likelihood) are applied on mixed pixels. In this study, Linear Spectral Mixture Model (LSMM) is used to estimate the proportion of water in boundary pixels. Firstly by applying an unsupervised clustering, the water body is identified approximately and a buffer area considered ensuring the selection of entire boundary pixels. Then LSMM is applied on this buffer region to estimate the fractional maps. However, resultant output of LSMM does not provide a sub-pixel map corresponding to water abundances. To tackle with this problem, Pixel Swapping (PS) algorithm is used to allocate sub-pixels within mixed pixels in such a way to maximize the spatial proximity of sub-pixels and pixels in the neighborhood. The water area of two segments of Tagliamento River (Italy) are mapped in sub-pixel resolution (10m) using a 30m Landsat image. To evaluate the proficiency of the proposed approach for sub-pixel boundary mapping, the image is also classified using a conventional hard classifier. A high resolution image of the same area is also classified and used as a reference for accuracy assessment. According to the results, sub-pixel map shows in average about 8 percent higher overall accuracy than hard classification and fits very well in the boundaries with the reference map.

  6. A CMOS image sensor with stacked photodiodes for lensless observation system of digital enzyme-linked immunosorbent assay

    NASA Astrophysics Data System (ADS)

    Takehara, Hironari; Miyazawa, Kazuya; Noda, Toshihiko; Sasagawa, Kiyotaka; Tokuda, Takashi; Kim, Soo Hyeon; Iino, Ryota; Noji, Hiroyuki; Ohta, Jun

    2014-01-01

    A CMOS image sensor with stacked photodiodes was fabricated using 0.18 µm mixed signal CMOS process technology. Two photodiodes were stacked at the same position of each pixel of the CMOS image sensor. The stacked photodiodes consist of shallow high-concentration N-type layer (N+), P-type well (PW), deep N-type well (DNW), and P-type substrate (P-sub). PW and P-sub were shorted to ground. By monitoring the voltage of N+ and DNW individually, we can observe two monochromatic colors simultaneously without using any color filters. The CMOS image sensor is suitable for fluorescence imaging, especially contact imaging such as a lensless observation system of digital enzyme-linked immunosorbent assay (ELISA). Since the fluorescence increases with time in digital ELISA, it is possible to observe fluorescence accurately by calculating the difference from the initial relation between the pixel values for both photodiodes.

  7. A CMOS Time-Resolved Fluorescence Lifetime Analysis Micro-System.

    PubMed

    Rae, Bruce R; Muir, Keith R; Gong, Zheng; McKendry, Jonathan; Girkin, John M; Gu, Erdan; Renshaw, David; Dawson, Martin D; Henderson, Robert K

    2009-01-01

    We describe a CMOS-based micro-system for time-resolved fluorescence lifetime analysis. It comprises a 16 × 4 array of single-photon avalanche diodes (SPADs) fabricated in 0.35 μm high-voltage CMOS technology with in-pixel time-gated photon counting circuitry and a second device incorporating an 8 × 8 AlInGaN blue micro-pixellated light-emitting diode (micro-LED) array bump-bonded to an equivalent array of LED drivers realized in a standard low-voltage 0.35 μm CMOS technology, capable of producing excitation pulses with a width of 777 ps (FWHM). This system replaces instrumentation based on lasers, photomultiplier tubes, bulk optics and discrete electronics with a PC-based micro-system. Demonstrator lifetime measurements of colloidal quantum dot and Rhodamine samples are presented. PMID:22291564

  8. A CMOS Time-Resolved Fluorescence Lifetime Analysis Micro-System

    PubMed Central

    Rae, Bruce R.; Muir, Keith R.; Gong, Zheng; McKendry, Jonathan; Girkin, John M.; Gu, Erdan; Renshaw, David; Dawson, Martin D.; Henderson, Robert K.

    2009-01-01

    We describe a CMOS-based micro-system for time-resolved fluorescence lifetime analysis. It comprises a 16 × 4 array of single-photon avalanche diodes (SPADs) fabricated in 0.35 μm high-voltage CMOS technology with in-pixel time-gated photon counting circuitry and a second device incorporating an 8 × 8 AlInGaN blue micro-pixellated light-emitting diode (micro-LED) array bump-bonded to an equivalent array of LED drivers realized in a standard low-voltage 0.35 μm CMOS technology, capable of producing excitation pulses with a width of 777 ps (FWHM). This system replaces instrumentation based on lasers, photomultiplier tubes, bulk optics and discrete electronics with a PC-based micro-system. Demonstrator lifetime measurements of colloidal quantum dot and Rhodamine samples are presented. PMID:22291564

  9. CMOS Amperometric ADC With High Sensitivity, Dynamic Range and Power Efficiency for Air Quality Monitoring.

    PubMed

    Li, Haitao; Boling, C Sam; Mason, Andrew J

    2016-08-01

    Airborne pollutants are a leading cause of illness and mortality globally. Electrochemical gas sensors show great promise for personal air quality monitoring to address this worldwide health crisis. However, implementing miniaturized arrays of such sensors demands high performance instrumentation circuits that simultaneously meet challenging power, area, sensitivity, noise and dynamic range goals. This paper presents a new multi-channel CMOS amperometric ADC featuring pixel-level architecture for gas sensor arrays. The circuit combines digital modulation of input currents and an incremental Σ∆ ADC to achieve wide dynamic range and high sensitivity with very high power efficiency and compact size. Fabricated in 0.5 [Formula: see text] CMOS, the circuit was measured to have 164 dB cross-scale dynamic range, 100 fA sensitivity while consuming only 241 [Formula: see text] and 0.157 [Formula: see text] active area per channel. Electrochemical experiments with liquid and gas targets demonstrate the circuit's real-time response to a wide range of analyte concentrations. PMID:27352395

  10. Hybrid CMOS SiPIN detectors as astronomical imagers

    NASA Astrophysics Data System (ADS)

    Simms, Lance Michael

    Charge Coupled Devices (CCDs) have dominated optical and x-ray astronomy since their inception in 1969. Only recently, through improvements in design and fabrication methods, have imagers that use Complimentary Metal Oxide Semiconductor (CMOS) technology gained ground on CCDs in scientific imaging. We are now in the midst of an era where astronomers might begin to design optical telescope cameras that employ CMOS imagers. The first three chapters of this dissertation are primarily composed of introductory material. In them, we discuss the potential advantages that CMOS imagers offer over CCDs in astronomical applications. We compare the two technologies in terms of the standard metrics used to evaluate and compare scientific imagers: dark current, read noise, linearity, etc. We also discuss novel features of CMOS devices and the benefits they offer to astronomy. In particular, we focus on a specific kind of hybrid CMOS sensor that uses Silicon PIN photodiodes to detect optical light in order to overcome deficiencies of commercial CMOS sensors. The remaining four chapters focus on a specific type of hybrid CMOS Silicon PIN sensor: the Teledyne Hybrid Visible Silicon PIN Imager (HyViSI). In chapters four and five, results from testing HyViSI detectors in the laboratory and at the Kitt Peak 2.1m telescope are presented. We present our laboratory measurements of the standard detector metrics for a number of HyViSI devices, ranging from 1k×1k to 4k×4k format. We also include a description of the SIDECAR readout circuit that was used to control the detectors. We then show how they performed at the telescope in terms of photometry, astrometry, variability measurement, and telescope focusing and guiding. Lastly, in the final two chapters we present results on detector artifacts such as pixel crosstalk, electronic crosstalk, and image persistence. One form of pixel crosstalk that has not been discussed elsewhere in the literature, which we refer to as Interpixel Charge

  11. A 128 × 128 Pixel Complementary Metal Oxide Semiconductor Image Sensor with an Improved Pixel Architecture for Detecting Modulated Light Signals

    NASA Astrophysics Data System (ADS)

    Yamamoto, Koji; Oya, Yu; Kagawa, Keiichiro; Nunoshita, Masahiro; Ohta, Jun; Watanabe, Kunihiro

    A complementary metal oxide semiconductor (CMOS) image sensor for the detection of modulated light under background illumination has been developed. When an object is illuminated by a modulated light source under background illumination the sensor enables the object alone to be captured. This paper describes improvements in pixel architecture for reducing fixed pattern noise (FPN) and improving the sensitivity of the image sensor. The improved 128 × 128 pixel CMOS image sensor with a column parallel analog-to-digital converter (ADC) circuit was fabricated using 0.35-mm CMOS technology. The resulting captured images are shown and the properties of improved pixel architecture are described. The image sensor has FPN of 1/28 that of the previous image sensor and an improved pixel architecture comprising a common in-pixel amp and a correlated double sampling (CDS) circuit. The use of a split photogate increases the sensitivity of the image sensor to 1.3 times that of the previous image sensor.

  12. Fast signal transfer in a large-area X-ray CMOS image sensor

    NASA Astrophysics Data System (ADS)

    Kim, M. S.; Kang, D. U.; Lee, D. H.; Kim, H.; Cho, G.; Jae, M.

    2014-08-01

    For 2-d X-ray imaging, such as mammography and non-destructive test, a sensor should have a large-area because the sensor for typical X-ray beams cannot use optical lens system. To make a large-area 2-d X-ray image sensor using crystal Si, a technique of tiling unit CMOS image sensors into 2 × 2 or 2 × 3 array can be used. In a unit CMOS image sensor made of most common 8-inch Si wafers, the signal line can be up to ~ 180 mm long. Then its parasitic capacitance is up to ~ 25 pF and its resistance is up to ~ 51 kΩ (0.18 μm, 1P3M process). This long signal line may enlarge the row time up to ~ 50 μsec in case of the signal from the top row pixels to the readout amplifiers located at the bottom of the sensor chip. The output signal pulse is typically characterized by three components in sequence; a charging time (a rising part), a reading time and a discharging time (a falling part). Among these, the discharging time is the longest, and it limits the speed or the frame rate of the X-ray imager. We proposed a forced discharging method which uses a bypass transistor in parallel with the current source of the column signal line. A chip for testing the idea was fabricated by a 0.18 μm process. A active pixel sensor with three transistors and a 3-π RC model of the long line were simulated together. The test results showed that the turning on-and-off of the proposed bypass transistor only during the discharging time could dramatically reduce the discharging time from ~ 50 μsec to ~ 2 μsec, which is the physically minimum time determined by the long metal line capacitance.

  13. High density pixel array

    NASA Technical Reports Server (NTRS)

    Wiener-Avnear, Eliezer (Inventor); McFall, James Earl (Inventor)

    2004-01-01

    A pixel array device is fabricated by a laser micro-milling method under strict process control conditions. The device has an array of pixels bonded together with an adhesive filling the grooves between adjacent pixels. The array is fabricated by moving a substrate relative to a laser beam of predetermined intensity at a controlled, constant velocity along a predetermined path defining a set of grooves between adjacent pixels so that a predetermined laser flux per unit area is applied to the material, and repeating the movement for a plurality of passes of the laser beam until the grooves are ablated to a desired depth. The substrate is of an ultrasonic transducer material in one example for fabrication of a 2D ultrasonic phase array transducer. A substrate of phosphor material is used to fabricate an X-ray focal plane array detector.

  14. Time-resolved Emission from Bright Hot Pixels of an Active Region Observed in the EUV Band with SDO/AIA and Multi-stranded Loop Modeling

    NASA Astrophysics Data System (ADS)

    Tajfirouze, E.; Reale, F.; Petralia, A.; Testa, P.

    2016-01-01

    Evidence of small amounts of very hot plasma has been found in active regions and might be an indication of impulsive heating released at spatial scales smaller than the cross-section of a single loop. We investigate the heating and substructure of coronal loops in the core of one such active region by analyzing the light curves in the smallest resolution elements of solar observations in two EUV channels (94 and 335 Å) from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory. We model the evolution of a bundle of strands heated by a storm of nanoflares by means of a hydrodynamic 0D loop model (EBTEL). The light curves obtained from a random combination of those of single strands are compared to the observed light curves either in a single pixel or in a row of pixels, simultaneously in the two channels, and using two independent methods: an artificial intelligent system (Probabilistic Neural Network) and a simple cross-correlation technique. We explore the space of the parameters to constrain the distribution of the heat pulses, their duration, their spatial size, and, as a feedback on the data, their signatures on the light curves. From both methods the best agreement is obtained for a relatively large population of events (1000) with a short duration (less than 1 minute) and a relatively shallow distribution (power law with index 1.5) in a limited energy range (1.5 decades). The feedback on the data indicates that bumps in the light curves, especially in the 94 Å channel, are signatures of a heating excess that occurred a few minutes before.

  15. Regenerative switching CMOS system

    DOEpatents

    Welch, J.D.

    1998-06-02

    Complementary Metal Oxide Semiconductor (CMOS) Schottky barrier Field Effect Transistor systems, which are a series combination of N and P-Channel MOSFETS, in which Source Schottky barrier junctions of the N and P-Channel Schottky barrier MOSFETS are electrically interconnected, (rather than the Drains as in conventional diffused junction CMOS), which Schottky barrier MOSFET system demonstrates Regenerative Inverting Switching Characteristics in use are disclosed. Both the N and P-Channel Schottky barrier MOSFET devices are unique in that they provide operational Drain Current vs. Drain to Source voltage as a function of Gate voltage only where the polarities of the Drain voltage and Gate voltage are opposite, referenced to the Source as a common terminal, and where the polarity of the voltage applied to the Gate is appropriate to cause Channel inversion. Experimentally derived results which demonstrate and verify the operation of N and P-Channel Schottky barrier MOSFETS actually fabricated on P and N-type Silicon respectively, by a common procedure using vacuum deposited Chromium as a Schottky barrier forming metal, are also provided. 14 figs.

  16. Regenerative switching CMOS system

    DOEpatents

    Welch, James D.

    1998-01-01

    Complementary Metal Oxide Semiconductor (CMOS) Schottky barrier Field Effect Transistor systems, which are a seriesed combination of N and P-Channel MOSFETS, in which Source Schottky barrier junctions of the N and P-Channel Schottky barrier MOSFETS are electically interconnected, (rather than the Drains as in conventional diffused junction CMOS), which Schottky barrier MOSFET system demonstrates Regenerative Inverting Switching Characteristics in use are disclosed. Both the N and P-Channel Schottky barrier MOSFET devices are unique in that they provide operational Drain Current vs. Drain to Source voltage as a function of Gate voltage only where the polarities of the Drain voltage and Gate voltage are opposite, referenced to the Source as a common terminal, and where the polarity of the voltage applied to the Gate is appropriate to cause Channel inversion. Experimentally derived results which demonstrate and verify the operation of N and P-Channel Schottky barrier MOSFETS actually fabricated on P and N-type Silicon respectively, by a common procedure using vacuum deposited Chromium as a Schottky barrier forming metal, are also provided.

  17. The Speedster-EXD - A New Event-Triggered Hybrid CMOS X-ray Detector

    NASA Astrophysics Data System (ADS)

    Griffith, Christopher; Falcone, Abe; Prieskorn, Zach; Burrows, David

    2015-04-01

    We present the characterization of a new event driven x-ray hybrid CMOS detector developed by Penn State University in collaboration with Teledyne Imaging Sensors. Hybrid CMOS detectors currently have many advantages over CCDs including lower susceptibility to radiation damage, lower power consumption, and faster read-out time to avoid pile-up. The Speedster-EXD hybrid CMOS detector has many new features that improve upon the previous generation of detectors including two new in-pixel features that reduce noise from known noise sources: (1) a low-noise, high-gain CTIA amplifier to eliminate interpixel capacitance crosstalk and (2) in-pixel CDS subtraction to reduce kTC noise. The most exciting new feature of the Speedster-EXD is an in-pixel comparator that enables read out of only the pixels which contain signal from an x-ray event. The comparator threshold can be set by the user so that only pixels with signal above the set threshold are read out. This comparator feature can increase effective frame rate by orders of magnitude. We present the read noise, dark current, interpixel capacitance, energy resolution, and gain variation measurements of two Speedster-EXD detectors.

  18. Integration of nanostructured planar diffractive lenses dedicated to near infrared detection for CMOS image sensors.

    PubMed

    Lopez, Thomas; Massenot, Sébastien; Estribeau, Magali; Magnan, Pierre; Pardo, Fabrice; Pelouard, Jean-Luc

    2016-04-18

    This paper deals with the integration of metallic and dielectric nanostructured planar lenses into a pixel from a silicon based CMOS image sensor, for a monochromatic application at 1.064 μm. The first is a Plasmonic Lens, based on the phase delay through nanoslits, which has been found to be hardly compatible with current CMOS technology and exhibits a notable metallic absorption. The second is a dielectric Phase-Fresnel Lens integrated at the top of a pixel, it exhibits an Optical Efficiency (OE) improved by a few percent and an angle of view of 50°. The third one is a metallic diffractive lens integrated inside a pixel, which shows a better OE and an angle of view of 24°. The last two lenses exhibit a compatibility with a spectral band close to 1.064 μm. PMID:27137315

  19. Smart CMOS image sensor for lightning detection and imaging.

    PubMed

    Rolando, Sébastien; Goiffon, Vincent; Magnan, Pierre; Corbière, Franck; Molina, Romain; Tulet, Michel; Bréart-de-Boisanger, Michel; Saint-Pé, Olivier; Guiry, Saïprasad; Larnaudie, Franck; Leone, Bruno; Perez-Cuevas, Leticia; Zayer, Igor

    2013-03-01

    We present a CMOS image sensor dedicated to lightning detection and imaging. The detector has been designed to evaluate the potentiality of an on-chip lightning detection solution based on a smart sensor. This evaluation is performed in the frame of the predevelopment phase of the lightning detector that will be implemented in the Meteosat Third Generation Imager satellite for the European Space Agency. The lightning detection process is performed by a smart detector combining an in-pixel frame-to-frame difference comparison with an adjustable threshold and on-chip digital processing allowing an efficient localization of a faint lightning pulse on the entire large format array at a frequency of 1 kHz. A CMOS prototype sensor with a 256×256 pixel array and a 60 μm pixel pitch has been fabricated using a 0.35 μm 2P 5M technology and tested to validate the selected detection approach. PMID:23458812

  20. IR CMOS: near infrared enhanced digital imaging (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Pralle, Martin U.; Carey, James E.; Joy, Thomas; Vineis, Chris J.; Palsule, Chintamani

    2015-08-01

    SiOnyx has demonstrated imaging at light levels below 1 mLux (moonless starlight) at video frame rates with a 720P CMOS image sensor in a compact, low latency camera. Low light imaging is enabled by the combination of enhanced quantum efficiency in the near infrared together with state of the art low noise image sensor design. The quantum efficiency enhancements are achieved by applying Black Silicon, SiOnyx's proprietary ultrafast laser semiconductor processing technology. In the near infrared, silicon's native indirect bandgap results in low absorption coefficients and long absorption lengths. The Black Silicon nanostructured layer fundamentally disrupts this paradigm by enhancing the absorption of light within a thin pixel layer making 5 microns of silicon equivalent to over 300 microns of standard silicon. This results in a demonstrate 10 fold improvements in near infrared sensitivity over incumbent imaging technology while maintaining complete compatibility with standard CMOS image sensor process flows. Applications include surveillance, nightvision, and 1064nm laser see spot. Imaging performance metrics will be discussed. Demonstrated performance characteristics: Pixel size : 5.6 and 10 um Array size: 720P/1.3Mpix Frame rate: 60 Hz Read noise: 2 ele/pixel Spectral sensitivity: 400 to 1200 nm (with 10x QE at 1064nm) Daytime imaging: color (Bayer pattern) Nighttime imaging: moonless starlight conditions 1064nm laser imaging: daytime imaging out to 2Km

  1. Large CMOS imager using hadamard transform based multiplexing

    NASA Technical Reports Server (NTRS)

    Karasik, Boris S.; Wadsworth, Mark V.

    2005-01-01

    We have developed a concept design for a large (10k x 10k) CMOS imaging array whose elements are grouped in small subarrays with N pixels in each. The subarrays are code-division multiplexed using the Hadamard Transform (HT) based encoding. The Hadamard code improves the signal-to-noise (SNR) ratio to the reference of the read-out amplifier by a factor of N^1/2. This way of grouping pixels reduces the number of hybridization bumps by N. A single chip layout has been designed and the architecture of the imager has been developed to accommodate the HT base multiplexing into the existing CMOS technology. The imager architecture allows for a trade-off between the speed and the sensitivity. The envisioned imager would operate at a speed >100 fps with the pixel noise < 20 e-. The power dissipation would be 100 pW/pixe1. The combination of the large format, high speed, high sensitivity and low power dissipation can be very attractive for space reconnaissance applications.

  2. A robust color signal processing with wide dynamic range WRGB CMOS image sensor

    NASA Astrophysics Data System (ADS)

    Kawada, Shun; Kuroda, Rihito; Sugawa, Shigetoshi

    2011-01-01

    We have developed a robust color reproduction methodology by a simple calculation with a new color matrix using the formerly developed wide dynamic range WRGB lateral overflow integration capacitor (LOFIC) CMOS image sensor. The image sensor was fabricated through a 0.18 μm CMOS technology and has a 45 degrees oblique pixel array, the 4.2 μm effective pixel pitch and the W pixels. A W pixel was formed by replacing one of the two G pixels in the Bayer RGB color filter. The W pixel has a high sensitivity through the visible light waveband. An emerald green and yellow (EGY) signal is generated from the difference between the W signal and the sum of RGB signals. This EGY signal mainly includes emerald green and yellow lights. These colors are difficult to be reproduced accurately by the conventional simple linear matrix because their wave lengths are in the valleys of the spectral sensitivity characteristics of the RGB pixels. A new linear matrix based on the EGY-RGB signal was developed. Using this simple matrix, a highly accurate color processing with a large margin to the sensitivity fluctuation and noise has been achieved.

  3. OLED-on-CMOS integration for optoelectronic sensor applications

    NASA Astrophysics Data System (ADS)

    Vogel, Uwe; Kreye, Daniel; Reckziegel, Sven; Törker, Michael; Grillberger, Christiane; Amelung, Jörg

    2007-02-01

    Highly-efficient, low-voltage organic light emitting diodes (OLEDs) are well suitable for post-processing integration onto the top metal layer of CMOS devices. This has been proven for OLED microdisplays so far. Moreover, OLEDon- CMOS technology may also be excellently suitable for various optoelectronic sensor applications by combining highly efficient emitters, use of low-cost materials and cost-effective manufacturing together with silicon-inherent photodetectors and CMOS circuitry. The use of OLEDs on CMOS substrates requires a top-emitting, low-voltage and highly efficient OLED structure. By reducing the operating voltage for the OLED below 5V, the costs for the CMOS process can be reduced, because a process without high-voltage option can be used. Red, orange, white, green and blue OLED-stacks with doped charge transport layers were prepared on different dualmetal layer CMOS test substrates without active transistor area. Afterwards, the different devices were measured and compared with respect to their performance (current, luminance, voltage, luminance dependence on viewing angle, optical outcoupling etc.). Low operating voltages of 2.4V at 100cd/m2 for the red p-i-n type phosphorescent emitting OLED stack, 2.5V at 100cd/m2 for the orange phosphorescent emitting OLED stack and 3.2V at 100cd/m2 for the white fluorescent emitting OLED have been achieved here. Therefore, those OLED stacks are suitable for use in a CMOS process even within a regular 5V process option. Moreover, the operating voltage achieved so far is expected to be reduced further when using different top electrode materials. Integrating such OLEDs on a CMOS-substrate provide a preferable choice for silicon-based optical microsystems targeted towards optoelectronic sensor applications, as there are integrated light barriers, optocouplers, or lab-onchip devices.

  4. Design and test of clock distribution circuits for the Macro Pixel ASIC

    NASA Astrophysics Data System (ADS)

    Gaioni, L.; De Canio, F.; Manghisoni, M.; Ratti, L.; Re, V.; Traversi, G.

    2016-07-01

    Clock distribution circuits account for a significant fraction of the power dissipation of the Macro Pixel ASIC (MPA), designed for the pixel layer readout of the so-called Pixel-Strip module in the innermost part of the CMS tracker at the High Luminosity LHC. A test chip including low power clock distribution circuits of the MPA has been designed in a 65 nm CMOS technology and thoroughly tested. This work summarizes the experimental results relevant to the prototype chip, focusing particularly on the power and speed performance and compares such results with those coming from circuit simulations.

  5. 128 x 128 pixel uncooled bolometric FPA for IR detection and imaging

    NASA Astrophysics Data System (ADS)

    Jerominek, Hubert; Pope, Timothy D.; Alain, Christine; Zhang, Rose; Lehoux, Mario; Picard, Francis; Fuchs, R. Wayne; Grenier, Carol; Rouleau, Yves; Cayer, Felix; Savard, Simon; Bilodeau, Ghislain; Couillard, Jean-Francois; Larouche, Carl; Ngo, Linh P.

    1998-10-01

    An uncooled IR camera making use of a 128 X 128 pixel bolometric FPA is presented. The reconfigurable bolometric focal plane array consist of 50 micrometer X 50 micrometer pixels and simple on-chip CMOS readout electronics which can be operated in random access, independent row and column clocking, and self-scanning modes. Depending on the selected pixel format and frame rate, the FPA's NETD varies from 0.52 degrees Celsius down to 0.10 degrees Celsius. The modular IR camera is software configured and provides RS170A analog video and 12-bit TTL format digital outputs.

  6. Selecting Pixels for Kepler Downlink

    NASA Technical Reports Server (NTRS)

    Bryson, Stephen T.; Jenkins, Jon M.; Klaus, Todd C.; Cote, Miles T.; Quintana, Elisa V.; Hall, Jennifer R.; Ibrahim, Khadeejah; Chandrasekaran, Hema; Caldwell, Douglas A.; Van Cleve, Jeffrey E.; Haas, Michael R.

    2010-01-01

    The Kepler mission monitors > 100,000 stellar targets using 42 2200 1024 pixel CCDs. Bandwidth constraints prevent the downlink of all 96 million pixels per 30-minute cadence, so the Kepler spacecraft downlinks a specified collection of pixels for each target. These pixels are selected by considering the object brightness, background and the signal-to-noise of each pixel, and are optimized to maximize the signal-to-noise ratio of the target. This paper describes pixel selection, creation of spacecraft apertures that efficiently capture selected pixels, and aperture assignment to a target. Diagnostic apertures, short-cadence targets and custom specified shapes are discussed.

  7. Performance of radiation-hard HV/HR CMOS sensors for the ATLAS inner detector upgrades

    NASA Astrophysics Data System (ADS)

    Liu, J.; Barbero, M.; Bilbao De Mendizabal, J.; Breugnon, P.; Godiot-Basolo, S.; Pangaud, P.; Rozanov, A.

    2016-03-01

    A major upgrade (Phase II Upgrade) to the Large Hadron Collider (LHC), scheduled for 2022, will be brought to the machine so as to extend its discovery potential. The upgraded LHC, called High-Luminosity LHC (HL-LHC), will run with a nominal leveled instantaneous luminosity of 5×1034 cm-2s-1, more than twice the expected luminosity. This unprecedented luminosity will result in higher occupancy and background radiations, which will request the design of a new Inner Tracker (ITk) which should have higher granularity, reduced material budget and improved radiation tolerance. A new pixel sensor concept based on High Voltage and High Resistivity CMOS (HV/HR CMOS) technology targeting the ATLAS inner detector upgrade is under exploration. With respect to the traditional hybrid pixel detector, the HV/HR CMOS sensor can potentially offer lower material budget, reduced pixel pitch and lower cost. Several prototypes have been designed and characterized within the ATLAS upgrade R&D effort, to investigate the detection and radiation hardness performance of various commercial technologies. An overview of the HV/HR CMOS sensor operation principle is described in this paper. The characterizations of three prototypes with X-ray, proton and neutron irradiation are also given.

  8. Further applications for mosaic pixel FPA technology

    NASA Astrophysics Data System (ADS)

    Liddiard, Kevin C.

    2011-06-01

    In previous papers to this SPIE forum the development of novel technology for next generation PIR security sensors has been described. This technology combines the mosaic pixel FPA concept with low cost optics and purpose-designed readout electronics to provide a higher performance and affordable alternative to current PIR sensor technology, including an imaging capability. Progressive development has resulted in increased performance and transition from conventional microbolometer fabrication to manufacture on 8 or 12 inch CMOS/MEMS fabrication lines. A number of spin-off applications have been identified. In this paper two specific applications are highlighted: high performance imaging IRFPA design and forest fire detection. The former involves optional design for small pixel high performance imaging. The latter involves cheap expendable sensors which can detect approaching fire fronts and send alarms with positional data via mobile phone or satellite link. We also introduce to this SPIE forum the application of microbolometer IR sensor technology to IoT, the Internet of Things.

  9. Beam test results of a monolithic pixel sensor in the 0.18 μm tower-jazz technology with high resistivity epitaxial layer

    NASA Astrophysics Data System (ADS)

    Mattiazzo, S.; Aimo, I.; Baudot, J.; Bedda, C.; La Rocca, P.; Perez, A.; Riggi, F.; Spiriti, E.

    2015-10-01

    The ALICE experiment at CERN will undergo a major upgrade in the second Long LHC Shutdown in the years 2018-2019; this upgrade includes the full replacement of the Inner Tracking System (ITS), deploying seven layers of Monolithic Active Pixel Sensors (MAPS). For the development of the new ALICE ITS, the Tower-Jazz 0.18 μm CMOS imaging sensor process has been chosen as it is possible to use full CMOS in the pixel and different silicon wafers (including high resistivity epitaxial layers). A large test campaign has been carried out on several small prototype chips, designed to optimize the pixel sensor layout and the front-end electronics. Results match the target requirements both in terms of performance and of radiation hardness. Following this development, the first full scale chips have been designed, submitted and are currently under test, with promising results. A telescope composed of 4 planes of Mimosa-28 and 2 planes of Mimosa-18 chips is under development at the DAFNE Beam Test Facility (BTF) at the INFN Laboratori Nazionali di Frascati (LNF) in Italy with the final goal to perform a comparative test of the full scale prototypes. The telescope has been recently used to test a Mimosa-22THRb chip (a monolithic pixel sensor built in the 0.18 μm Tower-Jazz process) and we foresee to perform tests on the full scale chips for the ALICE ITS upgrade at the beginning of 2015. In this contribution we will describe some first measurements of spatial resolution, fake hit rate and detection efficiency of the Mimosa-22THRb chip obtained at the BTF facility in June 2014 with an electron beam of 500 MeV.

  10. Development for Germanium Blocked Impurity Band Far-Infrared Image Sensors with Fully-Depleted Silicon-On-Insulator CMOS Readout Integrated Circuit

    NASA Astrophysics Data System (ADS)

    Wada, T.; Arai, Y.; Baba, S.; Hanaoka, M.; Hattori, Y.; Ikeda, H.; Kaneda, H.; Kochi, C.; Miyachi, A.; Nagase, K.; Nakaya, H.; Ohno, M.; Oyabu, S.; Suzuki, T.; Ukai, S.; Watanabe, K.; Yamamoto, K.

    2016-02-01

    We are developing far-infrared (FIR) imaging sensors for low-background and high-sensitivity applications such as infrared astronomy. Previous FIR monolithic imaging sensors, such as an extrinsic germanium photo-conductor (Ge PC) with a PMOS readout integrated circuit (ROIC) hybridized by indium pixel-to-pixel interconnection, had three difficulties: (1) short cut-off wavelength (120 \\upmu m), (2) large power consumption (10 \\upmu W/pixel), and (3) large mismatch in thermal expansion between the Ge PC and the Si ROIC. In order to overcome these difficulties, we developed (1) a blocked impurity band detector fabricated by a surface- activated bond technology, whose cut-off wavelength is longer than 160 \\upmu m, (2) a fully-depleted silicon-on-insulator CMOS ROIC which works below 4 K with 1 \\upmu W/pixel operating power, and (3) a new concept, Si-supported Ge detector, which shows tolerance to thermal cycling down to 3 K. With these new techniques, we are now developing a 32 × 32 FIR imaging sensor.

  11. Development for Germanium Blocked Impurity Band Far-Infrared Image Sensors with Fully-Depleted Silicon-On-Insulator CMOS Readout Integrated Circuit

    NASA Astrophysics Data System (ADS)

    Wada, T.; Arai, Y.; Baba, S.; Hanaoka, M.; Hattori, Y.; Ikeda, H.; Kaneda, H.; Kochi, C.; Miyachi, A.; Nagase, K.; Nakaya, H.; Ohno, M.; Oyabu, S.; Suzuki, T.; Ukai, S.; Watanabe, K.; Yamamoto, K.

    2016-07-01

    We are developing far-infrared (FIR) imaging sensors for low-background and high-sensitivity applications such as infrared astronomy. Previous FIR monolithic imaging sensors, such as an extrinsic germanium photo-conductor (Ge PC) with a PMOS readout integrated circuit (ROIC) hybridized by indium pixel-to-pixel interconnection, had three difficulties: (1) short cut-off wavelength (120 μm), (2) large power consumption (10 μ W/pixel), and (3) large mismatch in thermal expansion between the Ge PC and the Si ROIC. In order to overcome these difficulties, we developed (1) a blocked impurity band detector fabricated by a surface- activated bond technology, whose cut-off wavelength is longer than 160 μm, (2) a fully-depleted silicon-on-insulator CMOS ROIC which works below 4 K with 1 μW/pixel operating power, and (3) a new concept, Si-supported Ge detector, which shows tolerance to thermal cycling down to 3 K. With these new techniques, we are now developing a 32 × 32 FIR imaging sensor.

  12. Development for Germanium Blocked Impurity Band Far-Infrared Image Sensors with Fully-Depleted Silicon-On-Insulator CMOS Readout Integrated Circuit

    NASA Astrophysics Data System (ADS)

    Wada, T.; Arai, Y.; Baba, S.; Hanaoka, M.; Hattori, Y.; Ikeda, H.; Kaneda, H.; Kochi, C.; Miyachi, A.; Nagase, K.; Nakaya, H.; Ohno, M.; Oyabu, S.; Suzuki, T.; Ukai, S.; Watanabe, K.; Yamamoto, K.

    2016-07-01

    We are developing far-infrared (FIR) imaging sensors for low-background and high-sensitivity applications such as infrared astronomy. Previous FIR monolithic imaging sensors, such as an extrinsic germanium photo-conductor (Ge PC) with a PMOS readout integrated circuit (ROIC) hybridized by indium pixel-to-pixel interconnection, had three difficulties: (1) short cut-off wavelength (120 \\upmu m), (2) large power consumption (10 \\upmu W/pixel), and (3) large mismatch in thermal expansion between the Ge PC and the Si ROIC. In order to overcome these difficulties, we developed (1) a blocked impurity band detector fabricated by a surface- activated bond technology, whose cut-off wavelength is longer than 160 \\upmu m, (2) a fully-depleted silicon-on-insulator CMOS ROIC which works below 4 K with 1 \\upmu W/pixel operating power, and (3) a new concept, Si-supported Ge detector, which shows tolerance to thermal cycling down to 3 K. With these new techniques, we are now developing a 32 × 32 FIR imaging sensor.

  13. Use of CMOS imagers to measure high fluxes of charged particles

    NASA Astrophysics Data System (ADS)

    Servoli, L.; Tucceri, P.

    2016-03-01

    The measurement of high flux charged particle beams, specifically at medical accelerators and with small fields, poses several challenges. In this work we propose a single particle counting method based on CMOS imagers optimized for visible light collection, exploiting their very high spatial segmentation (> 3 106 pixels/cm2) and almost full efficiency detection capability. An algorithm to measure the charged particle flux with a precision of ~ 1% for fluxes up to 40 MHz/cm2 has been developed, using a non-linear calibration algorithm, and several CMOS imagers with different characteristics have been compared to find their limits on flux measurement.

  14. A 65 nm pixel readout ASIC with quick transverse momentum discrimination capabilities for the CMS Tracker at HL-LHC

    NASA Astrophysics Data System (ADS)

    Ceresa, D.; Kaplon, J.; Francisco, R.; Caratelli, A.; Kloukinas, K.; Marchioro, A.

    2016-01-01

    A readout ASIC for the hybrid pixel detector with the capability of performing quick recognition of particles with high transverse momentum has been designed for the requirements of the CMS Outer Tracker at the High Luminosity LHC . The particle momentum dicrimination capability represents the main challenge for this design together with the low power requirement: the constraint of low mass for the new tracker dictates a total power budget of less than 100 mW/cm2. The choice of a 65 nm CMOS technology has made it possible to satisfy this power requirement despite the fairly large amount of logic necessary to perform the momentum discrimination and the continuous operation at 40 MHz. Several techniques for low power have been used to implement this logic that performs cluster reduction, position offset correction and coordinate encoding. A prototype chip including a large part of the final functionality and the full front-end has been realized and comprises a matrix of 16 by 3 rectangular pixels of 100 μm × 1446 μm, providing 7.65 mm2 of segmented active area. Measurements of the analog front-end characteristics closely match the simulations and confirm the consumption of < 30 μA per pixel. Front-end characterization and irradiation results up to 150 MRad are also reported.

  15. High throughput optoelectronic smart pixel systems using diffractive optics

    NASA Astrophysics Data System (ADS)

    Chen, Chih-Hao

    1999-12-01

    Recent developments in digital video, multimedia technology and data networks have greatly increased the demand for high bandwidth communication channels and high throughput data processing. Electronics is particularly suited for switching, amplification and logic functions, while optics is more suitable for interconnections and communications with lower energy and crosstalk. In this research, we present the design, testing, integration and demonstration of several optoelectronic smart pixel devices and system architectures. These systems integrate electronic switching/processing capability with parallel optical interconnections to provide high throughput network communication and pipeline data processing. The Smart Pixel Array Cellular Logic processor (SPARCL) is designed in 0.8 m m CMOS and hybrid integrated with Multiple-Quantum-Well (MQW) devices for pipeline image processing. The Smart Pixel Network Interface (SAPIENT) is designed in 0.6 m m GaAs and monolithically integrated with LEDs to implement a highly parallel optical interconnection network. The Translucent Smart Pixel Array (TRANSPAR) design is implemented in two different versions. The first version, TRANSPAR-MQW, is designed in 0.5 m m CMOS and flip-chip integrated with MQW devices to provide 2-D pipeline processing and translucent networking using the Carrier- Sense-MultipleAccess/Collision-Detection (CSMA/CD) protocol. The other version, TRANSPAR-VM, is designed in 1.2 m m CMOS and discretely integrated with VCSEL-MSM (Vertical-Cavity-Surface- Emitting-Laser and Metal-Semiconductor-Metal detectors) chips and driver/receiver chips on a printed circuit board. The TRANSPAR-VM provides an option of using the token ring network protocol in addition to the embedded functions of TRANSPAR-MQW. These optoelectronic smart pixel systems also require micro-optics devices to provide high resolution, high quality optical interconnections and external source arrays. In this research, we describe an innovative

  16. Focal plane array readout integrated circuit with per-pixel analog-to-digital and digital-to-analog conversion

    NASA Astrophysics Data System (ADS)

    Kleinfelder, Stuart; Hottes, Alison; Pease, R. Fabian W.

    2000-07-01

    A pixel array readout integrated circuit (ROIC) containing per-pixel analog-to-digital conversion (ADC) and digital-to- analog conversion (DAC) for infrared detectors is presented with design and test result details. Fabricated in a standard 0.35 micron, 3.3 volt CMOS technology. the prototype consists of a linear array of 64 pixels, containing over 100 transistors per 30 by 30 micron pixel. The 8-bit per-pixel ADC is a Nyquist-rate single-slope design consisting of a three stage comparator and an 8 bit memory. This fully pixel- parallel ADC architecture operates in full-frame 'snapshot' mode and can reach over 1,000 frames per second. Each pixel also contains cascoded current source, globally biased to subtract an identical, fixed amount of current from each pixel in order to remove a common background signal by 'charge skimming.' It operates over more than 3 decades of current cancellation (approximately 10 pA to > 10 nA). As well, each pixel contains a 4 to 6+ bit current-mode DAC, intended to trim-out pixel-to-pixel variations in background current. It consists of 16 unit-cells of switched cascoded current sources per pixel, organized as two separately biased weights and controlled by a 16-bit per-pixel memory. The DAC operates over more than 4 decades of current cancellation (< 10 pA to approximately equals 100 nA) per least significant bit (LSB).

  17. Superior performance with sCMOS over EMCCD in super-resolution optical fluctuation imaging

    NASA Astrophysics Data System (ADS)

    Chen, Xuanze; Zeng, Zhiping; Li, Rongqin; Xue, Boxin; Xi, Peng; Sun, Yujie

    2016-06-01

    Super-resolution optical fluctuation imaging (SOFI) is a fast and low-cost live-cell optical nanoscopy for extracting subdiffraction information from the statistics of fluorescence intensity fluctuation. As SOFI is based on the fluctuation statistics, rather than the detection of single molecules, it poses unique requirements for imaging detectors, which still lack a systematic evaluation. Here, we analyze the influences of pixel sizes, frame rates, noise levels, and different gains in SOFI with simulations and experimental tests. Our analysis shows that the smaller pixel size and faster readout speed of scientific-grade complementary metal oxide semiconductor (sCMOS) enables SOFI to achieve high spatiotemporal resolution with a large field-of-view, which is especially beneficial for live-cell super-resolution imaging. Overall, as the performance of SOFI is relatively insensitive to the signal-to-noise ratio (SNR), the gain in pixel size and readout speed exceeds the loss in SNR, indicating sCMOS is superior to electron multiplying charge coupled device in context to SOFI in many cases. Super-resolution imaging of cellular microtubule structures with high-order SOFI is experimentally demonstrated at large field-of-view, taking advantage of the large pixel number and fast frame rate of sCMOS cameras.

  18. The Speedster-EXD - A New Event-Triggered Hybrid CMOS X-ray Detector

    NASA Astrophysics Data System (ADS)

    Griffith, Christopher; Falcone, Abraham; Prieskorn, Zachary; Burrows, David N.

    2014-08-01

    We present the characterization of a new event driven x-ray hybrid CMOS detector developed by Teledyne imaging Sensors in collaboration with Penn State University. Hybrid CMOS detectors currently have many advantages over CCD’s including lower susceptibility to radiation damage, lower power consumption, and faster read-out time to avoid pile-up. The Speedster-EXD includes an in-pixel comparator that enables read out of only the pixels with signal from an x-ray event. The comparator threshold can be set by the user and only pixels with signal above this threshold are read out. This event-driven readout feature can increase effective frame rates by orders of magnitude, enabling future x-ray missions. The Speedster-EXD hybrid CMOS detector also has additional features that improve upon our previous generation of detectors including: (1) a low-noise, high-gain CTIA amplifier to eliminate interpixel capacitance crosstalk, (2) four different gain modes to optimize either full well capacity or energy resolution, and (3) in-pixel CDS subtraction to reduce read noise. We present the read noise, dark current, interpixel capacitance, energy resolution, and gain variation measurements of the Speedster-EXD detector.

  19. The Speedster-EXD - A New Event-Triggered Hybrid CMOS X-ray Detector

    NASA Astrophysics Data System (ADS)

    Griffith, Christopher; Falcone, A.; Prieskorn, Z.; Burrows, D. N.

    2014-01-01

    We report on the development of a new Teledyne Imaging Systems hybrid CMOS x-ray detector called the Speedster-EXD which is capable of event-triggered read-out. Hybrid CMOS detectors currently have many advantages over CCDs including lower susceptibility to radiation damage, lower power consumption, and faster read out time to avoid pile-up. In addition to these advantages, the Speedster-EXD has new in-pixel circuitry which includes CDS subtraction to reduce read noise and a CTIA amplifier to eliminate interpixel capacitance crosstalk. The new circuitry also includes an in-pixel comparator that triggers on x-ray events. The comparator feature allows the detector to only read pixels in which an x-ray is detected. This feature increases the detector array effective frame rate by orders of magnitude. The current advantages of hybrid CMOS x-ray detectors combined with the new in-pixel circuitry makes the Speedster-EXD an ideal candidate for future high throughput x-ray missions requiring large-format silicon imagers.

  20. Gas pixel detectors for X-ray polarimetry applications

    NASA Astrophysics Data System (ADS)

    Bellazzini, R.; Angelini, F.; Baldini, L.; Bitti, F.; Brez, A.; Cavalca, F.; Del Prete, M.; Kuss, M.; Latronico, L.; Omodei, N.; Pinchera, M.; Massai, M. M.; Minuti, M.; Razzano, M.; Sgro, C.; Spandre, G.; Tenze, A.; Costa, E.; Soffitta, P.

    2006-05-01

    We discuss a new class of micro pattern gas detectors, the gas pixel detector (GPD), in which a complete integration between the gas amplification structure and the read-out electronics has been reached. An application-specific integrated circuit (ASIC) built in deep sub-micron technology has been developed to realize a monolithic device that is, at the same time, the pixelized charge collecting electrode and the amplifying, shaping and charge measuring front-end electronics. The CMOS chip has the top metal layer patterned in a matrix of 80 μm pitch hexagonal pixels, each of them directly connected to the underneath electronics chain which has been realized in the remaining five layers of the 0.35 μm VLSI technology. Results from tests of a first prototype of such detector with 2 k pixels and a full scale version with 22 k pixels are presented. The application of this device for Astronomical X-ray Polarimetry is discussed. The experimental detector response to polarized and unpolarized X-ray radiation is shown. Results from a full MonteCarlo simulation for two astronomical sources, the Crab Nebula and the Hercules X1, are also reported.

  1. The Speedster-EXD- A New Event-Driven Hybrid CMOS X-ray Detector

    NASA Astrophysics Data System (ADS)

    Griffith, Christopher V.; Falcone, Abraham D.; Prieskorn, Zachary R.; Burrows, David N.

    2016-01-01

    The Speedster-EXD is a new 64×64 pixel, 40-μm pixel pitch, 100-μm depletion depth hybrid CMOS x-ray detector with the capability of reading out only those pixels containing event charge, thus enabling fast effective frame rates. A global charge threshold can be specified, and pixels containing charge above this threshold are flagged and read out. The Speedster detector has also been designed with other advanced in-pixel features to improve performance, including a low-noise, high-gain capacitive transimpedance amplifier that eliminates interpixel capacitance crosstalk (IPC), and in-pixel correlated double sampling subtraction to reduce reset noise. We measure the best energy resolution on the Speedster-EXD detector to be 206 eV (3.5%) at 5.89 keV and 172 eV (10.0%) at 1.49 keV. The average IPC to the four adjacent pixels is measured to be 0.25%±0.2% (i.e., consistent with zero). The pixel-to-pixel gain variation is measured to be 0.80%±0.03%, and a Monte Carlo simulation is applied to better characterize the contributions to the energy resolution.

  2. Monolithic pixel detectors in a deep submicron SOI process

    SciTech Connect

    Deptuch, Grzegorz; /Fermilab

    2009-10-01

    A compact charge-signal processing chain, composed of a two-stage semi-gaussian preamplifier-signal shaping filter, a discriminator and a binary counter, implemented in a prototype pixel detector using 0.20 {micro}m CMOS Silicon on Insulator process, is presented. The gain of the analog chain was measured 0.76 V/fC at the signal peaking time about 300 ns and the equivalent noise charge referred to the input of 80 e{sup -1}.

  3. Ultra high-throughput single molecule spectroscopy with a 1024 pixel SPAD

    PubMed Central

    Colyer, Ryan A.; Scalia, Giuseppe; Villa, Federica A.; Guerrieri, Fabrizio; Tisa, Simone; Zappa, Franco; Cova, Sergio; Weiss, Shimon; Michalet, Xavier

    2013-01-01

    Single-molecule spectroscopy is a powerful approach to measuring molecular properties such as size, brightness, conformation, and binding constants. Due to the low concentrations in the single-molecule regime, measurements with good statistical accuracy require long acquisition times. Previously we showed a factor of 8 improvement in acquisition speed using a custom-CMOS 8x1 SPAD array. Here we present preliminary results with a 64X improvement in throughput obtained using a liquid crystal on silicon spatial light modulator (LCOS-SLM) and a novel standard CMOS 1024 pixel SPAD array, opening the way to truly high-throughput single-molecule spectroscopy. PMID:24386535

  4. Spectrally tunable pixel sensors

    NASA Astrophysics Data System (ADS)

    Langfelder, G.; Buffa, C.; Longoni, A. F.; Zaraga, F.

    2013-01-01

    They are here reported the developments and experimental results of fully operating matrices of spectrally tunable pixels based on the Transverse Field Detector (TFD). Unlike several digital imaging sensors based on color filter arrays or layered junctions, the TFD has the peculiar feature of having electrically tunable spectral sensitivities. In this way the sensor color space is not fixed a priori but can be real-time adjusted, e.g. for a better adaptation to the scene content or for multispectral capture. These advantages come at the cost of an increased complexity both for the photosensitive elements and for the readout electronics. The challenges in the realization of a matrix of TFD pixels are analyzed in this work. First experimental results on an 8x8 (x 3 colors) and on a 64x64 (x 3 colors) matrix will be presented and analyzed in terms of colorimetric and noise performance, and compared to simulation predictions.

  5. Predicted image quality of a CMOS APS X-ray detector across a range of mammographic beam qualities

    NASA Astrophysics Data System (ADS)

    Konstantinidis, A.

    2015-09-01

    Digital X-ray detectors based on Complementary Metal-Oxide- Semiconductor (CMOS) Active Pixel Sensor (APS) technology have been introduced in the early 2000s in medical imaging applications. In a previous study the X-ray performance (i.e. presampling Modulation Transfer Function (pMTF), Normalized Noise Power Spectrum (NNPS), Signal-to-Noise Ratio (SNR) and Detective Quantum Efficiency (DQE)) of the Dexela 2923MAM CMOS APS X-ray detector was evaluated within the mammographic energy range using monochromatic synchrotron radiation (i.e. 17-35 keV). In this study image simulation was used to predict how the mammographic beam quality affects image quality. In particular, the experimentally measured monochromatic pMTF, NNPS and SNR parameters were combined with various mammographic spectral shapes (i.e. Molybdenum/Molybdenum (Mo/Mo), Rhodium/Rhodium (Rh/Rh), Tungsten/Aluminium (W/Al) and Tungsten/Rhodium (W/Rh) anode/filtration combinations at 28 kV). The image quality was measured in terms of Contrast-to-Noise Ratio (CNR) using a synthetic breast phantom (4 cm thick with 50% glandularity). The results can be used to optimize the imaging conditions in order to minimize patient's Mean Glandular Dose (MGD).

  6. VeloPix: the pixel ASIC for the LHCb upgrade

    NASA Astrophysics Data System (ADS)

    Poikela, T.; De Gaspari, M.; Plosila, J.; Westerlund, T.; Ballabriga, R.; Buytaert, J.; Campbell, M.; Llopart, X.; Wyllie, K.; Gromov, V.; van Beuzekom, M.; Zivkovic, V.

    2015-01-01

    The LHCb Vertex Detector (VELO) will be upgraded in 2018 along with the other subsystems of LHCb in order to enable full readout at 40 MHz, with the data fed directly to the software triggering algorithms. The upgraded VELO is a lightweight hybrid pixel detector operating in vacuum in close proximity to the LHC beams. The readout will be provided by a dedicated front-end ASIC, dubbed VeloPix, matched to the LHCb readout requirements and the 55 × 55 μm VELO pixel dimensions. The chip is closely related to the Timepix3, from the Medipix family of ASICs. The principal challenge that the chip has to meet is a hit rate of up to 900 Mhits/s, resulting in a required output bandwidth of more than 16 Gbit/s. The occupancy across the chip is also very non-uniform, and the radiation levels reach an integrated 400 Mrad over the lifetime of the detector.VeloPix is a binary pixel readout chip with a data driven readout, designed in 130 nm CMOS technology. The pixels are combined into groups of 2 × 4 super pixels, enabling a shared logic and a reduction of bandwidth due to combined address and time stamp information. The pixel hits are combined with other simultaneous hits in the same super pixel, time stamped, and immediately driven off-chip. The analog front-end must be sufficiently fast to accurately time stamp the data, with a small enough dead time to minimize data loss in the most occupied regions of the chip. The data is driven off chip with a custom designed high speed serialiser. The current status of the ASIC design, the chip architecture and the simulations will be described.

  7. Digital pixel sensor array with logarithmic delta-sigma architecture.

    PubMed

    Mahmoodi, Alireza; Li, Jing; Joseph, Dileepan

    2013-01-01

    Like the human eye, logarithmic image sensors achieve wide dynamic range easily at video rates, but, unlike the human eye, they suffer from low peak signal-to-noise-and-distortion ratios (PSNDRs). To improve the PSNDR, we propose integrating a delta-sigma analog-to-digital converter (ADC) in each pixel. An image sensor employing this architecture is designed, built and tested in 0.18 micron complementary metal-oxide-semiconductor (CMOS) technology. It achieves a PSNDR better than state-of-the-art logarithmic sensors and comparable to the human eye. As the approach concerns an array of many ADCs, we use a small-area low-power delta-sigma design. For scalability, each pixel has its own decimator. The prototype is compared to a variety of other image sensors, linear and nonlinear, from industry and academia. PMID:23959239

  8. Method and apparatus of high dynamic range image sensor with individual pixel reset

    NASA Technical Reports Server (NTRS)

    Yadid-Pecht, Orly (Inventor); Pain, Bedabrata (Inventor); Fossum, Eric R. (Inventor)

    2001-01-01

    A wide dynamic range image sensor provides individual pixel reset to vary the integration time of individual pixels. The integration time of each pixel is controlled by column and row reset control signals which activate a logical reset transistor only when both signals coincide for a given pixel.

  9. The evaluation system of the 2-D scanning mirror based on CMOS sensor

    NASA Astrophysics Data System (ADS)

    Zeng, Gui-ying; Xie, Yuan; Chen, Jin-xing

    2010-10-01

    The high precision two-dimension scanning control technique is being developed for the next geosynchronous satellites FY-4 satellites which is using the three-axis stabilization stages. How to evaluate the point and scanning precision of the scanning mirror is one of the most important technologies. This paper describes the optoelectronic measure method based on CMOS sensors to evaluate the point and scanning precision of the scanning mirror in the laboratory, which is a 2-D dynamic angle measurement system. Some technologies, such as the sup-pixel orientation technology and the CMOS ROI technology, are used in the measurement system. The research shows that the angle measurement system based on IBIS-6600CMOS sensors can attain the 20°× 20° field of view, 2" accuracy, and 1Kframes/s speed. But the system is sensitive to the environment and it can only be worked in the laboratory.

  10. CMOS Integrated Carbon Nanotube Sensor

    SciTech Connect

    Perez, M. S.; Lerner, B.; Boselli, A.; Lamagna, A.; Obregon, P. D. Pareja; Julian, P. M.; Mandolesi, P. S.; Buffa, F. A.

    2009-05-23

    Recently carbon nanotubes (CNTs) have been gaining their importance as sensors for gases, temperature and chemicals. Advances in fabrication processes simplify the formation of CNT sensor on silicon substrate. We have integrated single wall carbon nanotubes (SWCNTs) with complementary metal oxide semiconductor process (CMOS) to produce a chip sensor system. The sensor prototype was designed and fabricated using a 0.30 um CMOS process. The main advantage is that the device has a voltage amplifier so the electrical measure can be taken and amplified inside the sensor. When the conductance of the SWCNTs varies in response to media changes, this is observed as a variation in the output tension accordingly.

  11. Precision of FLEET Velocimetry Using High-speed CMOS Camera Systems

    NASA Technical Reports Server (NTRS)

    Peters, Christopher J.; Danehy, Paul M.; Bathel, Brett F.; Jiang, Naibo; Calvert, Nathan D.; Miles, Richard B.

    2015-01-01

    Femtosecond laser electronic excitation tagging (FLEET) is an optical measurement technique that permits quantitative velocimetry of unseeded air or nitrogen using a single laser and a single camera. In this paper, we seek to determine the fundamental precision of the FLEET technique using high-speed complementary metal-oxide semiconductor (CMOS) cameras. Also, we compare the performance of several different high-speed CMOS camera systems for acquiring FLEET velocimetry data in air and nitrogen free-jet flows. The precision was defined as the standard deviation of a set of several hundred single-shot velocity measurements. Methods of enhancing the precision of the measurement were explored such as digital binning (similar in concept to on-sensor binning, but done in post-processing), row-wise digital binning of the signal in adjacent pixels and increasing the time delay between successive exposures. These techniques generally improved precision; however, binning provided the greatest improvement to the un-intensified camera systems which had low signal-to-noise ratio. When binning row-wise by 8 pixels (about the thickness of the tagged region) and using an inter-frame delay of 65 micro sec, precisions of 0.5 m/s in air and 0.2 m/s in nitrogen were achieved. The camera comparison included a pco.dimax HD, a LaVision Imager scientific CMOS (sCMOS) and a Photron FASTCAM SA-X2, along with a two-stage LaVision High Speed IRO intensifier. Excluding the LaVision Imager sCMOS, the cameras were tested with and without intensification and with both short and long inter-frame delays. Use of intensification and longer inter-frame delay generally improved precision. Overall, the Photron FASTCAM SA-X2 exhibited the best performance in terms of greatest precision and highest signal-to-noise ratio primarily because it had the largest pixels.

  12. Precision of FLEET Velocimetry Using High-Speed CMOS Camera Systems

    NASA Technical Reports Server (NTRS)

    Peters, Christopher J.; Danehy, Paul M.; Bathel, Brett F.; Jiang, Naibo; Calvert, Nathan D.; Miles, Richard B.

    2015-01-01

    Femtosecond laser electronic excitation tagging (FLEET) is an optical measurement technique that permits quantitative velocimetry of unseeded air or nitrogen using a single laser and a single camera. In this paper, we seek to determine the fundamental precision of the FLEET technique using high-speed complementary metal-oxide semiconductor (CMOS) cameras. Also, we compare the performance of several different high-speed CMOS camera systems for acquiring FLEET velocimetry data in air and nitrogen free-jet flows. The precision was defined as the standard deviation of a set of several hundred single-shot velocity measurements. Methods of enhancing the precision of the measurement were explored such as digital binning (similar in concept to on-sensor binning, but done in post-processing), row-wise digital binning of the signal in adjacent pixels and increasing the time delay between successive exposures. These techniques generally improved precision; however, binning provided the greatest improvement to the un-intensified camera systems which had low signal-to-noise ratio. When binning row-wise by 8 pixels (about the thickness of the tagged region) and using an inter-frame delay of 65 microseconds, precisions of 0.5 meters per second in air and 0.2 meters per second in nitrogen were achieved. The camera comparison included a pco.dimax HD, a LaVision Imager scientific CMOS (sCMOS) and a Photron FASTCAM SA-X2, along with a two-stage LaVision HighSpeed IRO intensifier. Excluding the LaVision Imager sCMOS, the cameras were tested with and without intensification and with both short and long inter-frame delays. Use of intensification and longer inter-frame delay generally improved precision. Overall, the Photron FASTCAM SA-X2 exhibited the best performance in terms of greatest precision and highest signal-to-noise ratio primarily because it had the largest pixels.

  13. Detection of pointing errors with CMOS-based camera in intersatellite optical communications

    NASA Astrophysics Data System (ADS)

    Yu, Si-yuan; Ma, Jing; Tan, Li-ying

    2005-01-01

    For very high data rates, intersatellite optical communications hold a potential performance edge over microwave communications. Acquisition and Tracking problem is critical because of the narrow transmit beam. A single array detector in some systems performs both spatial acquisition and tracking functions to detect pointing errors, so both wide field of view and high update rate is required. The past systems tend to employ CCD-based camera with complex readout arrangements, but the additional complexity reduces the applicability of the array based tracking concept. With the development of CMOS array, CMOS-based cameras can employ the single array detector concept. The area of interest feature of the CMOS-based camera allows a PAT system to specify portion of the array. The maximum allowed frame rate increases as the size of the area of interest decreases under certain conditions. A commercially available CMOS camera with 105 fps @ 640×480 is employed in our PAT simulation system, in which only part pixels are used in fact. Beams angle varying in the field of view can be detected after getting across a Cassegrain telescope and an optical focus system. Spot pixel values (8 bits per pixel) reading out from CMOS are transmitted to a DSP subsystem via IEEE 1394 bus, and pointing errors can be computed by the centroid equation. It was shown in test that: (1) 500 fps @ 100×100 is available in acquisition when the field of view is 1mrad; (2)3k fps @ 10×10 is available in tracking when the field of view is 0.1mrad.

  14. Free-space optical data transmission using wavelength-division-multiplexing with a dedicated CMOS image sensor for indoor optical wireless LAN

    NASA Astrophysics Data System (ADS)

    Kagawa, K.; Tanida, J.

    2009-08-01

    We have proposed a space- and wavelength-division-multiplexing (WDM) indoor optical wireless LAN system based on a custom CMOS image sensor to realize a compact, high-speed, and intelligent nodes and hub. The CMOS image sensor can detect multiple fast optical data concurrently as well as captures ordinary images from which positions of communication nodes or the hub is obtained. In this paper, with the CMOS image sensor, we demonstrate an application of WDM technique to downlinks. We fabricated a 64x64-pixel custom CMOS image sensor with 4-channel concurrent data acquisition function. Experimental results showed that the CMOS sensor received 10Mbps×3ch WDM data while capturing ordinary images.

  15. Optical readout of a triple-GEM detector by means of a CMOS sensor

    NASA Astrophysics Data System (ADS)

    Marafini, M.; Patera, V.; Pinci, D.; Sarti, A.; Sciubba, A.; Spiriti, E.

    2016-07-01

    In last years, the development of optical sensors has produced objects able to provide very interesting performance. Large granularity is offered along with a very high sensitivity. CMOS sensors with millions of pixels able to detect as few as two or three photons per pixel are commercially available and can be used to read-out the optical signals provided by tracking particle detectors. In this work the results obtained by optically reading-out a triple-GEM detector by a commercial CMOS sensor will be presented. A standard detector was assembled with a transparent window below the third GEM allowing the light to get out. The detector is supplied with an Ar/CF4 based gas mixture producing 650 nm wavelength photons matching the maximum quantum efficiency of the sensor.

  16. Characterization of total ionizing dose damage in COTS pinned photodiode CMOS image sensors

    NASA Astrophysics Data System (ADS)

    Wang, Zujun; Ma, Wuying; Huang, Shaoyan; Yao, Zhibin; Liu, Minbo; He, Baoping; Liu, Jing; Sheng, Jiangkun; Xue, Yuan

    2016-03-01

    The characterization of total ionizing dose (TID) damage in COTS pinned photodiode (PPD) CMOS image sensors (CISs) is investigated. The radiation experiments are carried out at a 60Co γ-ray source. The CISs are produced by 0.18-μm CMOS technology and the pixel architecture is 8T global shutter pixel with correlated double sampling (CDS) based on a 4T PPD front end. The parameters of CISs such as temporal domain, spatial domain, and spectral domain are measured at the CIS test system as the EMVA 1288 standard before and after irradiation. The dark current, random noise, dark signal non-uniformity (DSNU), photo response non-uniformity (PRNU), overall system gain, saturation output, dynamic range (DR), signal to noise ratio (SNR), quantum efficiency (QE), and responsivity versus the TID are reported. The behaviors of the tested CISs show remarkable degradations after radiation. The degradation mechanisms of CISs induced by TID damage are also analyzed.

  17. Design considerations for a new, high resolution Micro-Angiographic Fluoroscope based on a CMOS sensor (MAF-CMOS)

    PubMed Central

    Loughran, Brendan; Swetadri Vasan, S. N.; Singh, Vivek; Ionita, Ciprian N.; Jain, Amit; Bednarek, Daniel R.; Titus, Albert; Rudin, Stephen

    2013-01-01

    The detectors that are used for endovascular image-guided interventions (EIGI), particularly for neurovascular interventions, do not provide clinicians with adequate visualization to ensure the best possible treatment outcomes. Developing an improved x-ray imaging detector requires the determination of estimated clinical x-ray entrance exposures to the detector. The range of exposures to the detector in clinical studies was found for the three modes of operation: fluoroscopic mode, high frame-rate digital angiographic mode (HD fluoroscopic mode), and DSA mode. Using these estimated detector exposure ranges and available CMOS detector technical specifications, design requirements were developed to pursue a quantum limited, high resolution, dynamic x-ray detector based on a CMOS sensor with 50 μm pixel size. For the proposed MAF-CMOS, the estimated charge collected within the full exposure range was found to be within the estimated full well capacity of the pixels. Expected instrumentation noise for the proposed detector was estimated to be 50–1,300 electrons. Adding a gain stage such as a light image intensifier would minimize the effect of the estimated instrumentation noise on total image noise but may not be necessary to ensure quantum limited detector operation at low exposure levels. A recursive temporal filter may decrease the effective total noise by 2 to 3 times, allowing for the improved signal to noise ratios at the lowest estimated exposures despite consequent loss in temporal resolution. This work can serve as a guide for further development of dynamic x-ray imaging prototypes or improvements for existing dynamic x-ray imaging systems. PMID:24353389

  18. Design considerations for a new, high resolution Micro-Angiographic Fluoroscope based on a CMOS sensor (MAF-CMOS).

    PubMed

    Loughran, Brendan; Swetadri Vasan, S N; Singh, Vivek; Ionita, Ciprian N; Jain, Amit; Bednarek, Daniel R; Titus, Albert; Rudin, Stephen

    2013-03-01

    The detectors that are used for endovascular image-guided interventions (EIGI), particularly for neurovascular interventions, do not provide clinicians with adequate visualization to ensure the best possible treatment outcomes. Developing an improved x-ray imaging detector requires the determination of estimated clinical x-ray entrance exposures to the detector. The range of exposures to the detector in clinical studies was found for the three modes of operation: fluoroscopic mode, high frame-rate digital angiographic mode (HD fluoroscopic mode), and DSA mode. Using these estimated detector exposure ranges and available CMOS detector technical specifications, design requirements were developed to pursue a quantum limited, high resolution, dynamic x-ray detector based on a CMOS sensor with 50 μm pixel size. For the proposed MAF-CMOS, the estimated charge collected within the full exposure range was found to be within the estimated full well capacity of the pixels. Expected instrumentation noise for the proposed detector was estimated to be 50-1,300 electrons. Adding a gain stage such as a light image intensifier would minimize the effect of the estimated instrumentation noise on total image noise but may not be necessary to ensure quantum limited detector operation at low exposure levels. A recursive temporal filter may decrease the effective total noise by 2 to 3 times, allowing for the improved signal to noise ratios at the lowest estimated exposures despite consequent loss in temporal resolution. This work can serve as a guide for further development of dynamic x-ray imaging prototypes or improvements for existing dynamic x-ray imaging systems. PMID:24353389

  19. Design considerations for a new high resolution Micro-Angiographic Fluoroscope based on a CMOS sensor (MAF-CMOS)

    NASA Astrophysics Data System (ADS)

    Loughran, Brendan; Swetadri Vasan, S. N.; Singh, Vivek; Ionita, Ciprian N.; Jain, Amit; Bednarek, Daniel R.; Titus, Albert H.; Rudin, Stephen

    2013-03-01

    The detectors that are used for endovascular image-guided interventions (EIGI), particularly for neurovascular interventions, do not provide clinicians with adequate visualization to ensure the best possible treatment outcomes. Developing an improved x-ray imaging detector requires the determination of estimated clinical x-ray entrance exposures to the detector. The range of exposures to the detector in clinical studies was found for the three modes of operation: fluoroscopic mode, high frame-rate digital angiographic mode (HD fluoroscopic mode), and DSA mode. Using these estimated detector exposure ranges and available CMOS detector technical specifications, design requirements were developed to pursue a quantum limited, high resolution, dynamic x-ray detector based on a CMOS sensor with 50 μm pixel size. For the proposed MAF-CMOS, the estimated charge collected within the full exposure range was found to be within the estimated full well capacity of the pixels. Expected instrumentation noise for the proposed detector was estimated to be 50-1,300 electrons. Adding a gain stage such as a light image intensifier would minimize the effect of the estimated instrumentation noise on total image noise but may not be necessary to ensure quantum limited detector operation at low exposure levels. A recursive temporal filter may decrease the effective total noise by 2 to 3 times, allowing for the improved signal to noise ratios at the lowest estimated exposures despite consequent loss in temporal resolution. This work can serve as a guide for further development of dynamic x-ray imaging prototypes or improvements for existing dynamic x-ray imaging systems.

  20. The CMS pixel system

    NASA Astrophysics Data System (ADS)

    Bortoletto, Daniela; CMS Collaboration

    2007-09-01

    The CMS hybrid pixel detector is located at the core of the CMS tracker and will contribute significantly to track and vertex reconstruction. The detector is subdivided into a three-layer barrel, and two end-cap disks on either side of the interaction region. The system operating in the 25-ns beam crossing time of the LHC must be radiation hard, low mass, and robust. The construction of the barrel modules and the forward disks has started after extensive R&D. The status of the project is reported.

  1. Self-amplified CMOS image sensor using a current-mode readout circuit

    NASA Astrophysics Data System (ADS)

    Santos, Patrick M.; de Lima Monteiro, Davies W.; Pittet, Patrick

    2014-05-01

    The feature size of the CMOS processes decreased during the past few years and problems such as reduced dynamic range have become more significant in voltage-mode pixels, even though the integration of more functionality inside the pixel has become easier. This work makes a contribution on both sides: the possibility of a high signal excursion range using current-mode circuits together with functionality addition by making signal amplification inside the pixel. The classic 3T pixel architecture was rebuild with small modifications to integrate a transconductance amplifier providing a current as an output. The matrix with these new pixels will operate as a whole large transistor outsourcing an amplified current that will be used for signal processing. This current is controlled by the intensity of the light received by the matrix, modulated pixel by pixel. The output current can be controlled by the biasing circuits to achieve a very large range of output signal levels. It can also be controlled with the matrix size and this permits a very high degree of freedom on the signal level, observing the current densities inside the integrated circuit. In addition, the matrix can operate at very small integration times. Its applications would be those in which fast imaging processing, high signal amplification are required and low resolution is not a major problem, such as UV image sensors. Simulation results will be presented to support: operation, control, design, signal excursion levels and linearity for a matrix of pixels that was conceived using this new concept of sensor.

  2. CMOS Imaging Detectors as X-ray Detectors for Synchrotron Radiation Experiments

    SciTech Connect

    Yagi, Naoto; Uesugi, Kentaro; Inoue, Katsuaki

    2004-05-12

    CMOS imagers are matrix-addressed photodiode arrays, which have been utilized in devices such as commercially available digital cameras. The pixel size of CMOS imagers is usually larger than that of CCD and smaller than that of TFT, giving them a unique position. Although CMOS x-ray imaging devices have already become commercially available, they have not been used as an x-ray area detector in synchrotron radiation experiments. We tested performance of a CMOS detector from Rad-icon (Shad-o-Box1024) in medical imaging, small-angle scattering, and protein crystallography experiments. It has pixels of 0.048 mm square, read-out time of 0.45 sec, 12-bit ADC, and requires a frame grabber for image acquisition. The detection area is 5-cm square. It uses a Kodak Min-R scintillator screen as a phosphor. The sensitivity to x-rays with an energy less than 15 keV was low because of the thick window materials. Since the readout noise is high, the dynamic range is limited to 2000. The biggest advantages of this detector are cost-effectiveness (about 10,000 US dollars) and compactness (thickness < 3 cm, weight < 2 kg)

  3. A novel Bayer-like WRGB color filter array for CMOS image sensors

    NASA Astrophysics Data System (ADS)

    Honda, Hiroto; Iida, Yoshinori; Itoh, Go; Egawa, Yoshitaka; Seki, Hiromichi

    2007-02-01

    We have developed a CMOS image sensor with a novel color filter array(CFA) where one of the green pixels of the Bayer pattern was replaced with a white pixel. A transparent layer has been fabricated on the white pixel instead of a color filter to realize over 95% transmission for visible light with wavelengths of 400-700 nm. Pixel pitch of the device was 3.3 um and the number of pixels was 2 million (1600H x 1200V). The novel Bayer-like WRGB (White-Red-Green-Blue) CFA realized higher signal-to-noise ratios of interpolated R, G, and B values in low illumination (3lux) by 6dB, 1dB, and 6dB, respectively, compared with those of the Bayer pattern, with the low-noise pre-digital signal process. Furthermore, there was no degradation of either resolution or color representation for the interpolated image. This new CFA has a great potential to significantly increase the sensitivity of CMOS/CCD image sensors with digital signal processing technology.

  4. The speedster-EXD: a new event-triggered hybrid CMOS x-ray detector

    NASA Astrophysics Data System (ADS)

    Griffith, Christopher V.; Falcone, Abraham D.; Prieskorn, Zachary R.; Burrows, David N.

    2014-07-01

    We present preliminary characterization of the Speedster-EXD, a new event driven hybrid CMOS detector (HCD) developed in collaboration with Penn State University and Teledyne Imaging Systems. HCDs have advantages over CCDs including lower susceptibility to radiation damage, lower power consumption, and faster read-out time to avoid pile-up. They are deeply depleted and able to detect x-rays down to approximately 0.1 keV. The Speedster-EXD has additional in-pixel features compared to previously published HCDs including: (1) an in-pixel comparator that enables read out of only the pixels with signal from an x-ray event, (2) four different gain modes to optimize either full well capacity or energy resolution, (3) in-pixel CDS subtraction to reduce read noise, and (4) a low-noise, high-gain CTIA amplifier to eliminate interpixel capacitance crosstalk. When using the comparator feature, the user can set a comparator threshold and only pixels above the threshold will be read out. This feature can be run in two modes including single pixel readout in which only pixels above the threshold are read out and 3x3 readout where a 3×3 region centered on the central pixel of the X-ray event is read out. The comparator feature of the Speedster-EXD increases the detector array effective frame rate by orders of magnitude. The new features of the Speedster-EXD hybrid CMOS x-ray detector are particularly relevant to future high throughput x-ray missions requiring large-format silicon imagers.

  5. An Ultra-Low Power CMOS Image Sensor with On-Chip Energy Harvesting and Power Management Capability

    PubMed Central

    Cevik, Ismail; Huang, Xiwei; Yu, Hao; Yan, Mei; Ay, Suat U.

    2015-01-01

    An ultra-low power CMOS image sensor with on-chip energy harvesting and power management capability is introduced in this paper. The photodiode pixel array can not only capture images but also harvest solar energy. As such, the CMOS image sensor chip is able to switch between imaging and harvesting modes towards self-power operation. Moreover, an on-chip maximum power point tracking (MPPT)-based power management system (PMS) is designed for the dual-mode image sensor to further improve the energy efficiency. A new isolated P-well energy harvesting and imaging (EHI) pixel with very high fill factor is introduced. Several ultra-low power design techniques such as reset and select boosting techniques have been utilized to maintain a wide pixel dynamic range. The chip was designed and fabricated in a 1.8 V, 1P6M 0.18 µm CMOS process. Total power consumption of the imager is 6.53 µW for a 96 × 96 pixel array with 1 V supply and 5 fps frame rate. Up to 30 μW of power could be generated by the new EHI pixels. The PMS is capable of providing 3× the power required during imaging mode with 50% efficiency allowing energy autonomous operation with a 72.5% duty cycle. PMID:25756863

  6. Experimental and theoretical performance analysis for a CMOS-based high resolution image detector

    NASA Astrophysics Data System (ADS)

    Jain, Amit; Bednarek, Daniel R.; Rudin, Stephen

    2014-03-01

    Increasing complexity of endovascular interventional procedures requires superior x-ray imaging quality. Present stateof- the-art x-ray imaging detectors may not be adequate due to their inherent noise and resolution limitations. With recent developments, CMOS based detectors are presenting an option to fulfill the need for better image quality. For this work, a new CMOS detector has been analyzed experimentally and theoretically in terms of sensitivity, MTF and DQE. The detector (Dexela Model 1207, Perkin-Elmer Co., London, UK) features 14-bit image acquisition, a CsI phosphor, 75 μm pixels and an active area of 12 cm x 7 cm with over 30 fps frame rate. This detector has two modes of operations with two different full-well capacities: high and low sensitivity. The sensitivity and instrumentation noise equivalent exposure (INEE) were calculated for both modes. The detector modulation-transfer function (MTF), noise-power spectra (NPS) and detective quantum efficiency (DQE) were measured using an RQA5 spectrum. For the theoretical performance evaluation, a linear cascade model with an added aliasing stage was used. The detector showed excellent linearity in both modes. The sensitivity and the INEE of the detector were found to be 31.55 DN/μR and 0.55 μR in high sensitivity mode, while they were 9.87 DN/μR and 2.77 μR in low sensitivity mode. The theoretical and experimental values for the MTF and DQE showed close agreement with good DQE even at fluoroscopic exposure levels. In summary, the Dexela detector's imaging performance in terms of sensitivity, linear system metrics, and INEE demonstrates that it can overcome the noise and resolution limitations of present state-of-the-art x-ray detectors.

  7. Precision tracking with a single gaseous pixel detector

    NASA Astrophysics Data System (ADS)

    Tsigaridas, S.; van Bakel, N.; Bilevych, Y.; Gromov, V.; Hartjes, F.; Hessey, N. P.; de Jong, P.; Kluit, R.

    2015-09-01

    The importance of micro-pattern gaseous detectors has grown over the past few years after successful usage in a large number of applications in physics experiments and medicine. We develop gaseous pixel detectors using micromegas-based amplification structures on top of CMOS pixel readout chips. Using wafer post-processing we add a spark-protection layer and a grid to create an amplification region above the chip, allowing individual electrons released above the grid by the passage of ionising radiation to be recorded. The electron creation point is measured in 3D, using the pixel position for (x, y) and the drift time for z. The track can be reconstructed by fitting a straight line to these points. In this work we have used a pixel-readout-chip which is a small-scale prototype of Timepix3 chip (designed for both silicon and gaseous detection media). This prototype chip has several advantages over the existing Timepix chip, including a faster front-end (pre-amplifier and discriminator) and a faster TDC which reduce timewalk's contribution to the z position error. Although the chip is very small (sensitive area of 0.88 × 0.88mm2), we have built it into a detector with a short drift gap (1.3 mm), and measured its tracking performance in an electron beam at DESY. We present the results obtained, which lead to a significant improvement for the resolutions with respect to Timepix-based detectors.

  8. The NUC and blind pixel eliminating in the DTDI application

    NASA Astrophysics Data System (ADS)

    Su, Xiao Feng; Chen, Fan Sheng; Pan, Sheng Da; Gong, Xue Yi; Dong, Yu Cui

    2013-12-01

    AS infrared CMOS Digital TDI (Time Delay and integrate) has a simple structure, excellent performance and flexible operation, it has been used in more and more applications. Because of the limitation of the Production process level, the plane array of the infrared detector has a large NU (non-uniformity) and a certain blind pixel rate. Both of the two will raise the noise and lead to the TDI works not very well. In this paper, for the impact of the system performance, the most important elements are analyzed, which are the NU of the optical system, the NU of the Plane array and the blind pixel in the Plane array. Here a reasonable algorithm which considers the background removal and the linear response model of the infrared detector is used to do the NUC (Non-uniformity correction) process, when the infrared detector array is used as a Digital TDI. In order to eliminate the impact of the blind pixel, the concept of surplus pixel method is introduced in, through the method, the SNR (signal to noise ratio) can be improved and the spatial and temporal resolution will not be changed. Finally we use a MWIR (Medium Ware Infrared) detector to do the experiment and the result proves the effectiveness of the method.

  9. Design of a reconfigurable optical microprocessor for smart pixel applications

    NASA Astrophysics Data System (ADS)

    Vagheeswar, V. S.; Krishna Kumar, Shankar Raman; Chokhani, Arvind; Beyette, Fred R., Jr.

    2003-12-01

    The ever increasing demand for communication bandwidth and system interconnectivity has been a motivating factor behind the integration of optoelectronics device and conventional data processing circuitry. Over the last two decades, fiber optic components have become the dominant technology in the telecommunications industry. In last 5 years, optical interconnection techniques have been suggested as a solution to the interconnect density and bandwidth problems faced by electrical systems at the cabinet, PC-board and even chip level. Based on the smart pixel architectures in the last decade, the proposed chip monolithically integrates optical sensors with silicon CMOS based circuitry. This project incorporates an instruction fetch unit (IFU), that fetches the instructions from an external host computer, and a 2D-array of one-bit smart pixels called the processing element (PE). Each PE consists of an ALU, control logic, dual port register memory bank, photoreceiver circuit and associated driver circuits. By tiling these smart pixels in 2D, it is possible to form a programmable smart pixel array that is well suited to read optical page-oriented data types. The CASPR chip contains a 4x4 array of PEs connected to a single IFU. Inter PE communication has been established through nearest neighbor communication. Simultaneous communication to all the PEs is possible through global communication. The instruction set for this architecture is 17-bit long. The chip has been successfully fabricated in 0.5´ technology. We present in this paper the design and initial test results from the recent fabrication.

  10. The status of the CMS forward pixel detector

    SciTech Connect

    Tan, Ping; /Fermilab

    2006-01-01

    The silicon pixel detector is the innermost component of the CMS tracking system. It provides precise measurements of space points to allow effective pattern recognition in multiple track environments near the LHC interaction point. The end disks of the pixel detector, known as the Forward Pixel detector, are constructed mainly by the US-CMS collaborators. The design techniques, readout electronics, test beam activities, and construction status are reviewed.

  11. FPIX2: a radiation-hard pixel readout chip for BTeV

    NASA Astrophysics Data System (ADS)

    Christian, D. C.; Appel, J. A.; Cancelo, G.; Hoff, J.; Kwan, S.; Mekkaoui, A.; Yarema, R.; Wester, W.; Zimmermann, S.

    2001-11-01

    A radiation-hard pixel readout chip, FPIX2, is being developed at Fermilab for the recently approved BTeV experiment [A. Kulyavtsev, et al., Proposal for an Experiment to Measure Mixing, CP Violation and Rare Decays in Charm and Beauty Particle Decays at the Fermilab Collider (2000), http://www-btev.fnal.gov/public_documents/btev_proposal/]. Although designed for BTeV, this chip should also be appropriate for use by CDF and DZero. A short review of this development effort is presented. Particular attention is given to the circuit redesign which was made necessary by the decision to implement FPIX2 using a standard deep-submicron CMOS process rather than an explicitly radiation-hard CMOS technology, as originally planned. The results (including the effects of irradiation to ˜33 Mrad) of initial tests of prototype 0.25 μm CMOS devices are presented, as are plans for the balance of the development effort.

  12. The FE-I4 Pixel Readout Chip and the IBL Module

    SciTech Connect

    Barbero, Marlon; Arutinov, David; Backhaus, Malte; Fang, Xiao-Chao; Gonella, Laura; Hemperek, Tomasz; Karagounis, Michael; Hans, Kruger; Kruth, Andre; Wermes, Norbert; Breugnon, Patrick; Fougeron, Denis; Gensolen, Fabrice; Menouni, Mohsine; Rozanov, Alexander; Beccherle, Roberto; Darbo, Giovanni; Caminada, Lea; Dube, Sourabh; Fleury, Julien; Gnani, Dario; /LBL, Berkeley /NIKHEF, Amsterdam /Gottingen U. /SLAC

    2012-05-01

    FE-I4 is the new ATLAS pixel readout chip for the upgraded ATLAS pixel detector. Designed in a CMOS 130 nm feature size process, the IC is able to withstand higher radiation levels compared to the present generation of ATLAS pixel Front-End FE-I3, and can also cope with higher hit rate. It is thus suitable for intermediate radii pixel detector layers in the High Luminosity LHC environment, but also for the inserted layer at 3.3 cm known as the 'Insertable B-Layer' project (IBL), at a shorter timescale. In this paper, an introduction to the FE-I4 will be given, focusing on test results from the first full size FE-I4A prototype which has been available since fall 2010. The IBL project will be introduced, with particular emphasis on the FE-I4-based module concept.

  13. A memristor-based pixel implementing light-to-resistance conversion

    NASA Astrophysics Data System (ADS)

    Olumodeji, Olufemi A.; Bramanti, Alessandro P.; Gottardi, Massimo; Iannotta, Salvatore

    2016-02-01

    This letter reports a pixel architecture that implements a light-to-resistance encoder exploiting the properties of a memristor. A light-to-frequency (L2F) converter is adopted to drive a memristor with pulses, thus changing its resistance according with the light intensity. In a conventional L2F implementation, a binary counter is needed to store the number of pulses generated within the exposure time (Ti). In the proposed circuit, the binary counter has been replaced with an analog counterpart, made of a single memristor. This turns into a smaller pixel pitch, compared with an all-CMOS solution and analog nonvolatile characteristics. The proposed circuit has been simulated in a 3.3 V, 0.35 μm CMOS process, while the memristor behavior relies on the HP model.

  14. Test results of the Data Handling Processor for the DEPFET Pixel Vertex Detector

    NASA Astrophysics Data System (ADS)

    Lemarenko, M.; Hemperek, T.; Krüger, H.; Koch, M.; Lütticke, F.; Marinas, C.; Wermes, N.

    2013-01-01

    In the new Belle II detector, which is currently under construction at the SuperKEKB accelerator, a two layer pixel detector will be introduced to improve the vertex reconstruction in a ultra high luminosity environment. The pixel detector will be produced using the DEPFET technology. A new ASIC (Data Handling Processor or DHP) designed to steer the readout process, pre-process and compress the raw data has been developed. The DHP will be directly bump bonded to the balcony of the all-silicon DEPFET module. The current chip prototype has been produced in CMOS 90 nm. Its test results, including the data processing quality, the signal integrity of the gigabit transmission lines will be presented here. For the final chip, which will be produced using CMOS 65 nm, single event upset (SEU) cross sections were measured. An additional chip, containing memory blocks to be tested, was submitted and produced using this technology.

  15. Characterization of prototype full-field breast tomosynthesis by using a CMOS array coupled with a columnar CsI(Tl) scintillator

    NASA Astrophysics Data System (ADS)

    Choi, Jae-Gu; Park, Hye-Suk; Kim, Ye-Seul; Choi, Young-Wook; Ham, Tae-Hee; Kim, Hee-Joung

    2012-02-01

    We have developed a prototype full-field digital breast tomosynthesis (DBT) system by using a complementary-metal-oxide semiconductive (CMOS) array coupled with a columnar CsI(Tl) scintillator. The imaging system consists of a matrix with an active detector area of 3072 × 3888 pixels and a pixel pitch of 74.8 µm. For tomosynthesis imaging, the X-ray tube is automatically rotated in 3° increments in the shoot mode to acquire projection images at 15 different angles over a ±21° angular range in less than 10 s. The digital detector is stationary during image acquisition. In this research, we also carried out evaluation studies to characterize the performance of the system in different operational modes designed for the DBT system, e.g., binning mode and the range of view angles, in terms of the modulation transfer function (MTF), the normalized noise power spectra (NNPS), and the detective quantum efficiency (DQE): The MTF value measured at the Nyquist frequency was 18.49%, the NNPS value at zero frequency was about 1.93 × 10-5 (mm2), and the maximum value of DQE was about 47.09% for the full resolution. For the pixel binning mode, the MTF decreased more than it did for the full resolution mode due to the increased effective pixel size. However, the full resolution mode was more sensitive to noise than the pixel binning mode. For the scan angle of the DBT system, oblique incidence of X-rays on a detector caused blurring that reduced resolution. These results seem to be promising for the use of the DBT system in potential clinical applications and will provide important information when comparisons with other DBT systems are made.

  16. Commissioning of the ATLAS pixel detector

    SciTech Connect

    ATLAS Collaboration; Golling, Tobias

    2008-09-01

    The ATLAS pixel detector is a high precision silicon tracking device located closest to the LHC interaction point. It belongs to the first generation of its kind in a hadron collider experiment. It will provide crucial pattern recognition information and will largely determine the ability of ATLAS to precisely track particle trajectories and find secondary vertices. It was the last detector to be installed in ATLAS in June 2007, has been fully connected and tested in-situ during spring and summer 2008, and is ready for the imminent LHC turn-on. The highlights of the past and future commissioning activities of the ATLAS pixel system are presented.

  17. Radiation Tolerance Studies of BTeV Pixel Readout Chip Prototypes

    SciTech Connect

    Gabriele Chiodini et al.

    2001-09-11

    We report on several irradiation studies performed on BTeV preFPIX2 pixel readout chip prototypes exposed to a 200 MeV proton beam at the Indiana University Cyclotron Facility. The preFPIX2 pixel readout chip has been implemented in standard 0.25 micron CMOS technology following radiation tolerant design rules. The tests confirmed the radiation tolerance of the chip design to proton total dose of 26 MRad. In addition, non destructive radiation-induced single event upsets have been observed in on-chip static registers and the single bit upset cross section has been measured.

  18. SVGA AMOLED with world's highest pixel pitch

    NASA Astrophysics Data System (ADS)

    Prache, Olivier; Wacyk, Ihor

    2006-05-01

    We present the design and early evaluation results of the world's highest pixel pitch full-color 800x3x600- pixel, active matrix organic light emitting diode (AMOLED) color microdisplay for consumer and environmentally demanding applications. The design premises were aimed at improving small area uniformity as well as reducing the pixel size while expanding the functionality found in existing eMagin Corporations' microdisplay products without incurring any power consumption degradation when compared to existing OLED microdisplays produced by eMagin. The initial results of the first silicon prototype presented here demonstrate compliance with all major objectives as well as the validation of a new adaptive gamma correction technique that can operate automatically over temperature.

  19. A 960-fps sub-sampling object extraction CMOS image sensor with 12-bit column parallel ADCs and ALUs

    NASA Astrophysics Data System (ADS)

    Motohashi, Yuichi; Kubo, Takashi; Kanto, Hiroaki; Tate, Tomoyasu; Sugawa, Shigetoshi

    2007-02-01

    A CMOS image sensor with highly accurate object extraction pre-processing functions by 960-fps sub-sampling operation, 12-bit column parallel successive approximation ADCs and column parallel ALUs has been developed. The pixel is composed of four transistors type pixel which shares the source follower transistor and the pixel select transistor. The each ADC is composed of the noise and signal holding capacitance, the noise reduction circuit, the comparator and the small DAC that combined both the reference voltage ratios and capacitance ratios. In the ALU, the object categorization pre-processing is performed by the each macro block of 3 × 3 pixels which has a reference pixel and its neighboring eight pixels. The three image features which are the edge of object, the direction of edge-vector and the average of light-intensity of 3 × 3 pixels corresponded to each pixel are extracted by the ALUs. The image and the results of the object extraction pre-processing are outputted by every 60-fps. The image sensor was fabricated by 0.35-μm 2P3M technology. The pixel pitch is 5.3-μm, the number of pixels is 640H × 360V and the chip size is 4.9-mm square.

  20. Pixelation Effects in Weak Lensing

    NASA Technical Reports Server (NTRS)

    High, F. William; Rhodes, Jason; Massey, Richard; Ellis, Richard

    2007-01-01

    Weak gravitational lensing can be used to investigate both dark matter and dark energy but requires accurate measurements of the shapes of faint, distant galaxies. Such measurements are hindered by the finite resolution and pixel scale of digital cameras. We investigate the optimum choice of pixel scale for a space-based mission, using the engineering model and survey strategy of the proposed Supernova Acceleration Probe as a baseline. We do this by simulating realistic astronomical images containing a known input shear signal and then attempting to recover the signal using the Rhodes, Refregier, and Groth algorithm. We find that the quality of shear measurement is always improved by smaller pixels. However, in practice, telescopes are usually limited to a finite number of pixels and operational life span, so the total area of a survey increases with pixel size. We therefore fix the survey lifetime and the number of pixels in the focal plane while varying the pixel scale, thereby effectively varying the survey size. In a pure trade-off for image resolution versus survey area, we find that measurements of the matter power spectrum would have minimum statistical error with a pixel scale of 0.09' for a 0.14' FWHM point-spread function (PSF). The pixel scale could be increased to 0.16' if images dithered by exactly half-pixel offsets were always available. Some of our results do depend on our adopted shape measurement method and should be regarded as an upper limit: future pipelines may require smaller pixels to overcome systematic floors not yet accessible, and, in certain circumstances, measuring the shape of the PSF might be more difficult than those of galaxies. However, the relative trends in our analysis are robust, especially those of the surface density of resolved galaxies. Our approach thus provides a snapshot of potential in available technology, and a practical counterpart to analytic studies of pixelation, which necessarily assume an idealized shape

  1. Pixelation Effects in Weak Lensing

    NASA Astrophysics Data System (ADS)

    High, F. William; Rhodes, Jason; Massey, Richard; Ellis, Richard

    2007-11-01

    Weak gravitational lensing can be used to investigate both dark matter and dark energy but requires accurate measurements of the shapes of faint, distant galaxies. Such measurements are hindered by the finite resolution and pixel scale of digital cameras. We investigate the optimum choice of pixel scale for a space-based mission, using the engineering model and survey strategy of the proposed Supernova Acceleration Probe as a baseline. We do this by simulating realistic astronomical images containing a known input shear signal and then attempting to recover the signal using the Rhodes, Refregier, & Groth algorithm. We find that the quality of shear measurement is always improved by smaller pixels. However, in practice, telescopes are usually limited to a finite number of pixels and operational life span, so the total area of a survey increases with pixel size. We therefore fix the survey lifetime and the number of pixels in the focal plane while varying the pixel scale, thereby effectively varying the survey size. In a pure trade-off for image resolution versus survey area, we find that measurements of the matter power spectrum would have minimum statistical error with a pixel scale of 0.09" for a 0.14" FWHM point-spread function (PSF). The pixel scale could be increased to ~0.16" if images dithered by exactly half-pixel offsets were always available. Some of our results do depend on our adopted shape measurement method and should be regarded as an upper limit: future pipelines may require smaller pixels to overcome systematic floors not yet accessible, and, in certain circumstances, measuring the shape of the PSF might be more difficult than those of galaxies. However, the relative trends in our analysis are robust, especially those of the surface density of resolved galaxies. Our approach thus provides a snapshot of potential in available technology, and a practical counterpart to analytic studies of pixelation, which necessarily assume an idealized shape

  2. A two-step A/D conversion and column self-calibration technique for low noise CMOS image sensors.

    PubMed

    Bae, Jaeyoung; Kim, Daeyun; Ham, Seokheon; Chae, Youngcheol; Song, Minkyu

    2014-01-01

    In this paper, a 120 frames per second (fps) low noise CMOS Image Sensor (CIS) based on a Two-Step Single Slope ADC (TS SS ADC) and column self-calibration technique is proposed. The TS SS ADC is suitable for high speed video systems because its conversion speed is much faster (by more than 10 times) than that of the Single Slope ADC (SS ADC). However, there exist some mismatching errors between the coarse block and the fine block due to the 2-step operation of the TS SS ADC. In general, this makes it difficult to implement the TS SS ADC beyond a 10-bit resolution. In order to improve such errors, a new 4-input comparator is discussed and a high resolution TS SS ADC is proposed. Further, a feedback circuit that enables column self-calibration to reduce the Fixed Pattern Noise (FPN) is also described. The proposed chip has been fabricated with 0.13 μm Samsung CIS technology and the chip satisfies the VGA resolution. The pixel is based on the 4-TR Active Pixel Sensor (APS). The high frame rate of 120 fps is achieved at the VGA resolution. The measured FPN is 0.38 LSB, and measured dynamic range is about 64.6 dB. PMID:24999716

  3. A Two-Step A/D Conversion and Column Self-Calibration Technique for Low Noise CMOS Image Sensors

    PubMed Central

    Bae, Jaeyoung; Kim, Daeyun; Ham, Seokheon; Chae, Youngcheol; Song, Minkyu

    2014-01-01

    In this paper, a 120 frames per second (fps) low noise CMOS Image Sensor (CIS) based on a Two-Step Single Slope ADC (TS SS ADC) and column self-calibration technique is proposed. The TS SS ADC is suitable for high speed video systems because its conversion speed is much faster (by more than 10 times) than that of the Single Slope ADC (SS ADC). However, there exist some mismatching errors between the coarse block and the fine block due to the 2-step operation of the TS SS ADC. In general, this makes it difficult to implement the TS SS ADC beyond a 10-bit resolution. In order to improve such errors, a new 4-input comparator is discussed and a high resolution TS SS ADC is proposed. Further, a feedback circuit that enables column self-calibration to reduce the Fixed Pattern Noise (FPN) is also described. The proposed chip has been fabricated with 0.13 μm Samsung CIS technology and the chip satisfies the VGA resolution. The pixel is based on the 4-TR Active Pixel Sensor (APS). The high frame rate of 120 fps is achieved at the VGA resolution. The measured FPN is 0.38 LSB, and measured dynamic range is about 64.6 dB. PMID:24999716

  4. Improved Signal Chains for Readout of CMOS Imagers

    NASA Technical Reports Server (NTRS)

    Pain, Bedabrata; Hancock, Bruce; Cunningham, Thomas

    2009-01-01

    An improved generic design has been devised for implementing signal chains involved in readout from complementary metal oxide/semiconductor (CMOS) image sensors and for other readout integrated circuits (ICs) that perform equivalent functions. The design applies to any such IC in which output signal charges from the pixels in a given row are transferred simultaneously into sampling capacitors at the bottoms of the columns, then voltages representing individual pixel charges are read out in sequence by sequentially turning on column-selecting field-effect transistors (FETs) in synchronism with source-follower- or operational-amplifier-based amplifier circuits. The improved design affords the best features of prior source-follower-and operational- amplifier-based designs while overcoming the major limitations of those designs. The limitations can be summarized as follows: a) For a source-follower-based signal chain, the ohmic voltage drop associated with DC bias current flowing through the column-selection FET causes unacceptable voltage offset, nonlinearity, and reduced small-signal gain. b) For an operational-amplifier-based signal chain, the required bias current and the output noise increase superlinearly with size of the pixel array because of a corresponding increase in the effective capacitance of the row bus used to couple the sampled column charges to the operational amplifier. The effect of the bus capacitance is to simultaneously slow down the readout circuit and increase noise through the Miller effect.

  5. Fully CMOS analog and digital SiPMs

    NASA Astrophysics Data System (ADS)

    Zou, Yu; Villa, Federica; Bronzi, Danilo; Tisa, Simone; Tosi, Alberto; Zappa, Franco

    2015-03-01

    Silicon Photomultipliers (SiPMs) are emerging single photon detectors used in many applications requiring large active area, photon-number resolving capability and immunity to magnetic fields. We present three families of analog SiPM fabricated in a reliable and cost-effective fully standard planar CMOS technology with a total photosensitive area of 1×1 mm2. These three families have different active areas with fill-factors (21%, 58.3%, 73.7%) comparable to those of commercial SiPM, which are developed in vertical (current flow) custom technologies. The peak photon detection efficiency in the near-UV tops at 38% (fill-factor included) comparable to commercial custom-process ones and dark count rate density is just a little higher than the best-in-class commercial analog SiPMs. Thanks to the CMOS processing, these new SiPMs can be integrated together with active components and electronics both within the microcell and on-chip, in order to act at the microcell level or to perform global pre-processing. We also report CMOS digital SiPMs in the same standard CMOS technology, based on microcells with digitalized processing, all integrated on-chip. This CMOS digital SiPMs has four 32×1 cells (128 microcells), each consisting of SPAD, active quenching circuit with adjustable dead time, digital control (to switch off noisy SPADs and readout position of detected photons), and fast trigger output signal. The achieved 20% fill-factor is still very good.

  6. Solid-state image sensor with focal-plane digital photon-counting pixel array

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R. (Inventor); Pain, Bedabrata (Inventor)

    1995-01-01

    A photosensitive layer such as a-Si for a UV/visible wavelength band is provided for low light level imaging with at least a separate CMOS amplifier directly connected to each PIN photodetector diode to provide a focal-plane array of NxN pixels, and preferably a separate photon-counting CMOS circuit directly connected to each CMOS amplifier, although one row of counters may be time shared for reading out the photon flux rate of each diode in the array, together with a buffer memory for storing all rows of the NxN image frame before transfer to suitable storage. All CMOS circuitry is preferably fabricated in the same silicon layer as the PIN photodetector diode for a monolithic structure, but when the wavelength band of interest requires photosensitive material different from silicon, the focal-plane array may be fabricated separately on a different semiconductor layer bump-bonded or otherwise bonded for a virtually monolithic structure with one free terminal of each diode directly connected to the input terminal of its CMOS amplifier and digital counter for integration of the photon flux rate at each photodetector of the array.

  7. Design methodology: edgeless 3D ASICs with complex in-pixel processing for pixel detectors

    NASA Astrophysics Data System (ADS)

    Fahim, Farah; Deptuch, Grzegorz W.; Hoff, James R.; Mohseni, Hooman

    2015-08-01

    The design methodology for the development of 3D integrated edgeless pixel detectors with in-pixel processing using Electronic Design Automation (EDA) tools is presented. A large area 3 tier 3D detector with one sensor layer and two ASIC layers containing one analog and one digital tier, is built for x-ray photon time of arrival measurement and imaging. A full custom analog pixel is 65μm x 65μm. It is connected to a sensor pixel of the same size on one side, and on the other side it has approximately 40 connections to the digital pixel. A 32 x 32 edgeless array without any peripheral functional blocks constitutes a sub-chip. The sub-chip is an indivisible unit, which is further arranged in a 6 x 6 array to create the entire 1.248cm x 1.248cm ASIC. Each chip has 720 bump-bond I/O connections, on the back of the digital tier to the ceramic PCB. All the analog tier power and biasing is conveyed through the digital tier from the PCB. The assembly has no peripheral functional blocks, and hence the active area extends to the edge of the detector. This was achieved by using a few flavors of almost identical analog pixels (minimal variation in layout) to allow for peripheral biasing blocks to be placed within pixels. The 1024 pixels within a digital sub-chip array have a variety of full custom, semi-custom and automated timing driven functional blocks placed together. The methodology uses a modified mixed-mode on-top digital implementation flow to not only harness the tool efficiency for timing and floor-planning but also to maintain designer control over compact parasitically aware layout. The methodology uses the Cadence design platform, however it is not limited to this tool.

  8. Design methodology: edgeless 3D ASICs with complex in-pixel processing for pixel detectors

    SciTech Connect

    Fahim Farah, Fahim Farah; Deptuch, Grzegorz W.; Hoff, James R.; Mohseni, Hooman

    2015-08-28

    The design methodology for the development of 3D integrated edgeless pixel detectors with in-pixel processing using Electronic Design Automation (EDA) tools is presented. A large area 3 tier 3D detector with one sensor layer and two ASIC layers containing one analog and one digital tier, is built for x-ray photon time of arrival measurement and imaging. A full custom analog pixel is 65μm x 65μm. It is connected to a sensor pixel of the same size on one side, and on the other side it has approximately 40 connections to the digital pixel. A 32 x 32 edgeless array without any peripheral functional blocks constitutes a sub-chip. The sub-chip is an indivisible unit, which is further arranged in a 6 x 6 array to create the entire 1.248cm x 1.248cm ASIC. Each chip has 720 bump-bond I/O connections, on the back of the digital tier to the ceramic PCB. All the analog tier power and biasing is conveyed through the digital tier from the PCB. The assembly has no peripheral functional blocks, and hence the active area extends to the edge of the detector. This was achieved by using a few flavors of almost identical analog pixels (minimal variation in layout) to allow for peripheral biasing blocks to be placed within pixels. The 1024 pixels within a digital sub-chip array have a variety of full custom, semi-custom and automated timing driven functional blocks placed together. The methodology uses a modified mixed-mode on-top digital implementation flow to not only harness the tool efficiency for timing and floor-planning but also to maintain designer control over compact parasitically aware layout. The methodology uses the Cadence design platform, however it is not limited to this tool.

  9. A CMOS-based on-chip neural interface device equipped with integrated LED array for optogenetics.

    PubMed

    Tokuda, T; Miyatani, T; Maezawa, Y; Kobayashi, T; Noda, T; Sasagawa, K; Ohta, J

    2012-01-01

    A novel CMOS-based neural interface device equipped with an integrated micro light source array was proposed and demonstrated. Target application of the device is optogenetics. GaInN LED array formed on sapphire substrate was successfully assembled with a multifunctional CMOS image sensor which is capable of injecting current via any of the pixel. We demonstrated addressable LED operation with the present device. The device has advantages such as simultaneous multi-site stimulation and on-chip optical imaging, that are not available with previously reported LED array device for optogenetics. PMID:23367087

  10. On-chip nanostructures for polarization imaging and multispectral sensing using dedicated layers of modified CMOS processes

    NASA Astrophysics Data System (ADS)

    Junger, Stephan; Tschekalinskij, Wladimir; Verwaal, Nanko; Weber, Norbert

    2011-03-01

    Sub-wavelength gratings and hole arrays in metal films are applicable for polarization and spectral selective sensors, respectively. We demonstrate the fabrication of wire grid polarizers using standard complementary metal-oxide semiconductor (CMOS) processes. Extraordinary optical transmission of hole arrays was achieved by using the dedicated layer of a modified CMOS process. The structures were simulated using the finite-difference time-domain (FDTD) method and fabricated using the work flow of integrated circuits. A high-speed polarization image sensor with a pixel size of 6 μm was designed and demonstrated, and multispectral sensing was implemented using nanostructures with different spectral filter performances on a single chip.

  11. CMOS output buffer wave shaper

    NASA Technical Reports Server (NTRS)

    Albertson, L.; Whitaker, S.; Merrell, R.

    1990-01-01

    As the switching speeds and densities of Digital CMOS integrated circuits continue to increase, output switching noise becomes more of a problem. A design technique which aids in the reduction of switching noise is reported. The output driver stage is analyzed through the use of an equivalent RLC circuit. The results of the analysis are used in the design of an output driver stage. A test circuit based on these techniques is being submitted to MOSIS for fabrication.

  12. THE KEPLER PIXEL RESPONSE FUNCTION

    SciTech Connect

    Bryson, Stephen T.; Haas, Michael R.; Dotson, Jessie L.; Koch, David G.; Borucki, William J.; Tenenbaum, Peter; Jenkins, Jon M.; Chandrasekaran, Hema; Caldwell, Douglas A.; Klaus, Todd; Gilliland, Ronald L.

    2010-04-20

    Kepler seeks to detect sequences of transits of Earth-size exoplanets orbiting solar-like stars. Such transit signals are on the order of 100 ppm. The high photometric precision demanded by Kepler requires detailed knowledge of how the Kepler pixels respond to starlight during a nominal observation. This information is provided by the Kepler pixel response function (PRF), defined as the composite of Kepler's optical point-spread function, integrated spacecraft pointing jitter during a nominal cadence and other systematic effects. To provide sub-pixel resolution, the PRF is represented as a piecewise-continuous polynomial on a sub-pixel mesh. This continuous representation allows the prediction of a star's flux value on any pixel given the star's pixel position. The advantages and difficulties of this polynomial representation are discussed, including characterization of spatial variation in the PRF and the smoothing of discontinuities between sub-pixel polynomial patches. On-orbit super-resolution measurements of the PRF across the Kepler field of view are described. Two uses of the PRF are presented: the selection of pixels for each star that maximizes the photometric signal-to-noise ratio for that star, and PRF-fitted centroids which provide robust and accurate stellar positions on the CCD, primarily used for attitude and plate scale tracking. Good knowledge of the PRF has been a critical component for the successful collection of high-precision photometry by Kepler.

  13. Region-of-interest cone beam computed tomography (ROI CBCT) with a high resolution CMOS detector

    NASA Astrophysics Data System (ADS)

    Jain, A.; Takemoto, H.; Silver, M. D.; Nagesh, S. V. S.; Ionita, C. N.; Bednarek, D. R.; Rudin, S.

    2015-03-01

    Cone beam computed tomography (CBCT) systems with rotational gantries that have standard flat panel detectors (FPD) are widely used for the 3D rendering of vascular structures using Feldkamp cone beam reconstruction algorithms. One of the inherent limitations of these systems is limited resolution (<3 lp/mm). There are systems available with higher resolution but their small FOV limits them to small animal imaging only. In this work, we report on region-of-interest (ROI) CBCT with a high resolution CMOS detector (75 μm pixels, 600 μm HR-CsI) mounted with motorized detector changer on a commercial FPD-based C-arm angiography gantry (194 μm pixels, 600 μm HL-CsI). A cylindrical CT phantom and neuro stents were imaged with both detectors. For each detector a total of 209 images were acquired in a rotational protocol. The technique parameters chosen for the FPD by the imaging system were used for the CMOS detector. The anti-scatter grid was removed and the incident scatter was kept the same for both detectors with identical collimator settings. The FPD images were reconstructed for the 10 cm x10 cm FOV and the CMOS images were reconstructed for a 3.84 cm x 3.84 cm FOV. Although the reconstructed images from the CMOS detector demonstrated comparable contrast to the FPD images, the reconstructed 3D images of the neuro stent clearly showed that the CMOS detector improved delineation of smaller objects such as the stent struts (~70 μm) compared to the FPD. Further development and the potential for substantial clinical impact are suggested.

  14. Spatial optical crosstalk in CMOS image sensors integrated with plasmonic color filters.

    PubMed

    Yu, Yan; Chen, Qin; Wen, Long; Hu, Xin; Zhang, Hui-Fang

    2015-08-24

    Imaging resolution of complementary metal oxide semiconductor (CMOS) image sensor (CIS) keeps increasing to approximately 7k × 4k. As a result, the pixel size shrinks down to sub-2μm, which greatly increases the spatial optical crosstalk. Recently, plasmonic color filter was proposed as an alternative to conventional colorant pigmented ones. However, there is little work on its size effect and the spatial optical crosstalk in a model of CIS. By numerical simulation, we investigate the size effect of nanocross array plasmonic color filters and analyze the spatial optical crosstalk of each pixel in a Bayer array of a CIS with a pixel size of 1μm. It is found that the small pixel size deteriorates the filtering performance of nanocross color filters and induces substantial spatial color crosstalk. By integrating the plasmonic filters in the low Metal layer in standard CMOS process, the crosstalk reduces significantly, which is compatible to pigmented filters in a state-of-the-art backside illumination CIS. PMID:26368174

  15. Using Polynomials to Simplify Fixed Pattern Noise and Photometric Correction of Logarithmic CMOS Image Sensors

    PubMed Central

    Li, Jing; Mahmoodi, Alireza; Joseph, Dileepan

    2015-01-01

    An important class of complementary metal-oxide-semiconductor (CMOS) image sensors are those where pixel responses are monotonic nonlinear functions of light stimuli. This class includes various logarithmic architectures, which are easily capable of wide dynamic range imaging, at video rates, but which are vulnerable to image quality issues. To minimize fixed pattern noise (FPN) and maximize photometric accuracy, pixel responses must be calibrated and corrected due to mismatch and process variation during fabrication. Unlike literature approaches, which employ circuit-based models of varying complexity, this paper introduces a novel approach based on low-degree polynomials. Although each pixel may have a highly nonlinear response, an approximately-linear FPN calibration is possible by exploiting the monotonic nature of imaging. Moreover, FPN correction requires only arithmetic, and an optimal fixed-point implementation is readily derived, subject to a user-specified number of bits per pixel. Using a monotonic spline, involving cubic polynomials, photometric calibration is also possible without a circuit-based model, and fixed-point photometric correction requires only a look-up table. The approach is experimentally validated with a logarithmic CMOS image sensor and is compared to a leading approach from the literature. The novel approach proves effective and efficient. PMID:26501287

  16. Using polynomials to simplify fixed pattern noise and photometric correction of logarithmic CMOS image sensors.

    PubMed

    Li, Jing; Mahmoodi, Alireza; Joseph, Dileepan

    2015-01-01

    An important class of complementary metal-oxide-semiconductor (CMOS) image sensors are those where pixel responses are monotonic nonlinear functions of light stimuli. This class includes various logarithmic architectures, which are easily capable of wide dynamic range imaging, at video rates, but which are vulnerable to image quality issues. To minimize fixed pattern noise (FPN) and maximize photometric accuracy, pixel responses must be calibrated and corrected due to mismatch and process variation during fabrication. Unlike literature approaches, which employ circuit-based models of varying complexity, this paper introduces a novel approach based on low-degree polynomials. Although each pixel may have a highly nonlinear response, an approximately-linear FPN calibration is possible by exploiting the monotonic nature of imaging. Moreover, FPN correction requires only arithmetic, and an optimal fixed-point implementation is readily derived, subject to a user-specified number of bits per pixel. Using a monotonic spline, involving cubic polynomials, photometric calibration is also possible without a circuit-based model, and fixed-point photometric correction requires only a look-up table. The approach is experimentally validated with a logarithmic CMOS image sensor and is compared to a leading approach from the literature. The novel approach proves effective and efficient. PMID:26501287

  17. Technology and design of an active-matrix OLED on crystalline silicon direct-view display for a wristwatch computer

    NASA Astrophysics Data System (ADS)

    Sanford, James L.; Schlig, Eugene S.; Prache, Olivier; Dove, Derek B.; Ali, Tariq A.; Howard, Webster E.

    2002-02-01

    The IBM Research Division and eMagin Corp. jointly have developed a low-power VGA direct view active matrix OLED display, fabricated on a crystalline silicon CMOS chip. The display is incorporated in IBM prototype wristwatch computers running the Linus operating system. IBM designed the silicon chip and eMagin developed the organic stack and performed the back-end-of line processing and packaging. Each pixel is driven by a constant current source controlled by a CMOS RAM cell, and the display receives its data from the processor memory bus. This paper describes the OLED technology and packaging, and outlines the design of the pixel and display electronics and the processor interface. Experimental results are presented.

  18. CMOS downsizing toward sub-10 nm

    NASA Astrophysics Data System (ADS)

    Iwai, Hiroshi

    2004-04-01

    Recently, CMOS downsizing has been accelerated very aggressively in both production and research level, and even transistor operation of a 6 nm gate length p-channel MOSFET was reported in a conference. However, many serious problems are expected for implementing such small-geometry MOSFETs into large scale integrated circuits, and it is still questionable whether we can successfully introduce sub-10 nm CMOS LSIs into the market or not. In this paper, limitation and its possible causes for the downscaling of CMOS towards sub-10 nm are discussed with consideration of past CMOS predictions for the limitation.

  19. Increasing Linear Dynamic Range of a CMOS Image Sensor

    NASA Technical Reports Server (NTRS)

    Pain, Bedabrata

    2007-01-01

    A generic design and a corresponding operating sequence have been developed for increasing the linear-response dynamic range of a complementary metal oxide/semiconductor (CMOS) image sensor. The design provides for linear calibrated dual-gain pixels that operate at high gain at a low signal level and at low gain at a signal level above a preset threshold. Unlike most prior designs for increasing dynamic range of an image sensor, this design does not entail any increase in noise (including fixed-pattern noise), decrease in responsivity or linearity, or degradation of photometric calibration. The figure is a simplified schematic diagram showing the circuit of one pixel and pertinent parts of its column readout circuitry. The conventional part of the pixel circuit includes a photodiode having a small capacitance, CD. The unconventional part includes an additional larger capacitance, CL, that can be connected to the photodiode via a transfer gate controlled in part by a latch. In the high-gain mode, the signal labeled TSR in the figure is held low through the latch, which also helps to adapt the gain on a pixel-by-pixel basis. Light must be coupled to the pixel through a microlens or by back illumination in order to obtain a high effective fill factor; this is necessary to ensure high quantum efficiency, a loss of which would minimize the efficacy of the dynamic- range-enhancement scheme. Once the level of illumination of the pixel exceeds the threshold, TSR is turned on, causing the transfer gate to conduct, thereby adding CL to the pixel capacitance. The added capacitance reduces the conversion gain, and increases the pixel electron-handling capacity, thereby providing an extension of the dynamic range. By use of an array of comparators also at the bottom of the column, photocharge voltages on sampling capacitors in each column are compared with a reference voltage to determine whether it is necessary to switch from the high-gain to the low-gain mode. Depending upon

  20. INDEP approach for leakage reduction in nanoscale CMOS circuits

    NASA Astrophysics Data System (ADS)

    Sharma, Vijay Kumar; Pattanaik, Manisha; Raj, Balwinder

    2015-02-01

    Complementary metal oxide semiconductor (CMOS) technology scaling for improving speed and functionality turns leakage power one of the major concerns for nanoscale circuits design. The minimization of leakage power is a rising challenge for the design of the existing and future nanoscale CMOS circuits. This paper presents a novel, input-dependent, transistor-level, low leakage and reliable INput DEPendent (INDEP) approach for nanoscale CMOS circuits. INDEP approach is based on Boolean logic calculations for the input signals of the extra inserted transistors within the logic circuit. The gate terminals of extra inserted transistors depend on the primary input combinations of the logic circuits. The appropriate selection of input gate voltages of INDEP transistors are reducing the leakage current efficiently along with rail to rail output voltage swing. The important characteristic of INDEP approach is that it works well in both active as well as standby modes of the circuits. This approach overcomes the limitations created by the prevalent current leakage reduction techniques. The simulation results indicate that INDEP approach mitigates 41.6% and 35% leakage power for 1-bit full adder and ISCAS-85 c17 benchmark circuit, respectively, at 32 nm bulk CMOS technology node.

  1. PIXELS: Using field-based learning to investigate students' concepts of pixels and sense of scale

    NASA Astrophysics Data System (ADS)

    Pope, A.; Tinigin, L.; Petcovic, H. L.; Ormand, C. J.; LaDue, N.

    2015-12-01

    Empirical work over the past decade supports the notion that a high level of spatial thinking skill is critical to success in the geosciences. Spatial thinking incorporates a host of sub-skills such as mentally rotating an object, imagining the inside of a 3D object based on outside patterns, unfolding a landscape, and disembedding critical patterns from background noise. In this study, we focus on sense of scale, which refers to how an individual quantified space, and is thought to develop through kinesthetic experiences. Remote sensing data are increasingly being used for wide-reaching and high impact research. A sense of scale is critical to many areas of the geosciences, including understanding and interpreting remotely sensed imagery. In this exploratory study, students (N=17) attending the Juneau Icefield Research Program participated in a 3-hour exercise designed to study how a field-based activity might impact their sense of scale and their conceptions of pixels in remotely sensed imagery. Prior to the activity, students had an introductory remote sensing lecture and completed the Sense of Scale inventory. Students walked and/or skied the perimeter of several pixel types, including a 1 m square (representing a WorldView sensor's pixel), a 30 m square (a Landsat pixel) and a 500 m square (a MODIS pixel). The group took reflectance measurements using a field radiometer as they physically traced out the pixel. The exercise was repeated in two different areas, one with homogenous reflectance, and another with heterogeneous reflectance. After the exercise, students again completed the Sense of Scale instrument and a demographic survey. This presentation will share the effects and efficacy of the field-based intervention to teach remote sensing concepts and to investigate potential relationships between students' concepts of pixels and sense of scale.

  2. High-content analysis of single cells directly assembled on CMOS sensor based on color imaging.

    PubMed

    Tanaka, Tsuyoshi; Saeki, Tatsuya; Sunaga, Yoshihiko; Matsunaga, Tadashi

    2010-12-15

    A complementary metal oxide semiconductor (CMOS) image sensor was applied to high-content analysis of single cells which were assembled closely or directly onto the CMOS sensor surface. The direct assembling of cell groups on CMOS sensor surface allows large-field (6.66 mm×5.32 mm in entire active area of CMOS sensor) imaging within a second. Trypan blue-stained and non-stained cells in the same field area on the CMOS sensor were successfully distinguished as white- and blue-colored images under white LED light irradiation. Furthermore, the chemiluminescent signals of each cell were successfully visualized as blue-colored images on CMOS sensor only when HeLa cells were placed directly on the micro-lens array of the CMOS sensor. Our proposed approach will be a promising technique for real-time and high-content analysis of single cells in a large-field area based on color imaging. PMID:20728336

  3. Implementation of pixel level digital TDI for scanning type LWIR FPAs

    NASA Astrophysics Data System (ADS)

    Ceylan, Omer; Kayahan, Huseyin; Yazici, Melik; Afridi, Sohaib; Shafique, Atia; Gurbuz, Yasar

    2014-07-01

    Implementation of a CMOS digital readout integrated circuit (DROIC) based on pixel level digital time delay integration (TDI) for scanning type LWIR focal plane arrays (FPAs) is presented. TDI is implemented on 8 pixels with over sampling rate of 3. Analog signal integrated on integration capacitor is converted to digital domain in pixel, and digital data is transferred to TDI summation counters, where contributions of 8 pixels are added. Output data is 16 bit, where 8 bits are allocated for most significant bits and 8 bits for least significant bits. Control block of the ROIC, which is responsible of generating timing diagram for switches controlling the pixels and summation counters, is realized with VerilogHDL. Summation counters and parallel-to-serial converter to convert 16 bit parallel output data to single bit output are also realized with Verilog HDL. Synthesized verilog netlists are placed&routed and combined with analog under-pixel part of the design. Quantization noise of analog-to-digital conversion is less than 500e-. Since analog signal is converted to digital domain in-pixel, inaccuracies due to analog signal routing over large chip area is eliminated. ROIC is fabricated with 0.18μm CMOS process and chip area is 10mm2. Post-layout simulation results of the implemented design are presented. ROIC is programmable through serial or parallel interface. Input referred noise of ROIC is less than 750 rms electron, while power consumption is less than 30mW. ROIC is designed to perform in cryogenic temperatures.

  4. Performance comparison of CMOS-based photodiodes for high-resolution and high-sensitivity digital mammography

    NASA Astrophysics Data System (ADS)

    Bae, J. H.; Cho, M.; Kim, M. S.; Lee, D. H.; Cho, G.

    2011-12-01

    In order to develop a high-resolution and high-sensitivity digital mamographic detector, to use a commercially-available and well-developed CMOS image sensor (CIS) process can be a cost-effective way. However, in any commercial CIS process, several different types of n- or p-layers can be used so that various pn-junction structures could be formed depending on the choice of n- and p-layer combination. We performed a comparative analysis on the characteristics of three types of photodiodes formed on a high-resistivity p-type epitaxial wafer by applying three available n-layer processes in order to develop the high-sensitivity photodiode for a scintillator-based X-ray imaging detector. As a preliminar study, a small test-version CIS chip with an 80 × 80 pixel array of a 3-transistor active pixel sensor structure, 50 μm pitch and 80{%} fill factor was fabricated. The pixel area is subdivided into four 40 × 40 sub-arrays and 3 different types of photodides are designed for each sub-array by using n+, n- and n-well layers. All other components are designed to be identical for impartial comparison of the photodiodes only. Among 3 types, the n-/p-epi photodiode exhibited high charge-to-voltage gain (0.86 μV/e-), high quantum efficiency (49% at 532 nm wavelength) and low dark current (294 pA/cm2). The test CIS chip was coupled to a phosphor screen, Lanex Fine or Lanex Regular, both composed of Gd2O2S:Tb, and was tested using X-rays in a mammography setting. Among 6 cases, n-/p-epi photodiode coupled with the Lanex Regular also showed the highest sensitivity of 30.5 mV/mR.

  5. NV-CMOS HD camera for day/night imaging

    NASA Astrophysics Data System (ADS)

    Vogelsong, T.; Tower, J.; Sudol, Thomas; Senko, T.; Chodelka, D.

    2014-06-01

    SRI International (SRI) has developed a new multi-purpose day/night video camera with low-light imaging performance comparable to an image intensifier, while offering the size, weight, ruggedness, and cost advantages enabled by the use of SRI's NV-CMOS HD digital image sensor chip. The digital video output is ideal for image enhancement, sharing with others through networking, video capture for data analysis, or fusion with thermal cameras. The camera provides Camera Link output with HD/WUXGA resolution of 1920 x 1200 pixels operating at 60 Hz. Windowing to smaller sizes enables operation at higher frame rates. High sensitivity is achieved through use of backside illumination, providing high Quantum Efficiency (QE) across the visible and near infrared (NIR) bands (peak QE <90%), as well as projected low noise (<2h+) readout. Power consumption is minimized in the camera, which operates from a single 5V supply. The NVCMOS HD camera provides a substantial reduction in size, weight, and power (SWaP) , ideal for SWaP-constrained day/night imaging platforms such as UAVs, ground vehicles, fixed mount surveillance, and may be reconfigured for mobile soldier operations such as night vision goggles and weapon sights. In addition the camera with the NV-CMOS HD imager is suitable for high performance digital cinematography/broadcast systems, biofluorescence/microscopy imaging, day/night security and surveillance, and other high-end applications which require HD video imaging with high sensitivity and wide dynamic range. The camera comes with an array of lens mounts including C-mount and F-mount. The latest test data from the NV-CMOS HD camera will be presented.

  6. Swap intensified WDR CMOS module for I2/LWIR fusion

    NASA Astrophysics Data System (ADS)

    Ni, Yang; Noguier, Vincent

    2015-05-01

    The combination of high resolution visible-near-infrared low light sensor and moderate resolution uncooled thermal sensor provides an efficient way for multi-task night vision. Tremendous progress has been made on uncooled thermal sensors (a-Si, VOx, etc.). It's possible to make a miniature uncooled thermal camera module in a tiny 1cm3 cube with <1W power consumption. For silicon based solid-state low light CCD/CMOS sensors have observed also a constant progress in terms of readout noise, dark current, resolution and frame rate. In contrast to thermal sensing which is intrinsic day&night operational, the silicon based solid-state sensors are not yet capable to do the night vision performance required by defense and critical surveillance applications. Readout noise, dark current are 2 major obstacles. The low dynamic range at high sensitivity mode of silicon sensors is also an important limiting factor, which leads to recognition failure due to local or global saturations & blooming. In this context, the image intensifier based solution is still attractive for the following reasons: 1) high gain and ultra-low dark current; 2) wide dynamic range and 3) ultra-low power consumption. With high electron gain and ultra low dark current of image intensifier, the only requirement on the silicon image pickup device are resolution, dynamic range and power consumption. In this paper, we present a SWAP intensified Wide Dynamic Range CMOS module for night vision applications, especially for I2/LWIR fusion. This module is based on a dedicated CMOS image sensor using solar-cell mode photodiode logarithmic pixel design which covers a huge dynamic range (> 140dB) without saturation and blooming. The ultra-wide dynamic range image from this new generation logarithmic sensor can be used directly without any image processing and provide an instant light accommodation. The complete module is slightly bigger than a simple ANVIS format I2 tube with <500mW power consumption.

  7. Novel CMOS readout techniques for uncooled pyroelectric IR FPA

    NASA Astrophysics Data System (ADS)

    Sun, Tai-Ping; Chin, Yuan-Lung; Chung, Wen-Yaw; Hsiung, Shen-Kan; Chou, Jung-Chuan

    1998-09-01

    Based on the application of the source follower per detector (SFD) input biasing technique, a new redout structure for the IR focal-plane-array (FPA), called the variable gain source follower per detector (VGSFD) is proposed and analyzed. The readout circuit of VGSFD of a unit cell of pyroelectric sensor under investigation, is composed of a source follower per detector circuit, high gain amplifier, and the reset switch. The VGSFD readout chip has been designed in 0.5 micrometers double-poly-double-metal n-well CMOS technology in various formats from 8 by 8 to 128 by 128. The experimental 8 by 8 VGSFD measurement results of the fabricated readout chip at room temperature have successfully verified both the readout function and performance. The high gain, low power, high sensitivity readout performances are achieved in a 50 by 50 micrometers (superscript 2) pixel size.

  8. A new visible watermarking technique applied to CMOS image sensor

    NASA Astrophysics Data System (ADS)

    Yu, Pingping; Shang, Yan; Li, Chunming

    2013-10-01

    This paper presents a new visible watermarking solution for CMOS image sensor which can enhance secure features of captured images. Visible watermarks are embedded in the Bayer format image data and can be transferred by the subsequent interpolation process. A piecewise function is setup based on the gray scale resolution characteristics of human eyes. Watermark stretch factor can be adaptively chosen according to the gray value of the current pixel. The advantage of this algorithm is that the watermark has the same visibility in different image brightness region. A number of color images have been used to test the method. In order to check the robustness of watermarked images, we conducted adding noise and filtering experiments, results show that the visibility of watermark is also good after the experiments. The approach allows a digital watermark to be embedded in an image immediately upon its capture, before leaving the imaging chip.

  9. Hybrid backside illuminated CMOS image sensors possessing low crosstalk

    NASA Astrophysics Data System (ADS)

    Ramachandra Rao, Padmakumar; De Munck, Koen; Minoglou, Kyriaki; De Vos, Joeri; Sabuncuoglu, Deniz; De Moor, Piet

    2011-11-01

    Backside illuminated (BSI) hybrid CMOS image sensors possessing excellent spectral response (> 80% between 400nm-800nm) have been previously reported by us. Particularly challenging with BSI imagers is to combine such sensitivity, with low electrical inter-pixel crosstalk (or charge-dispersion). Employing thick bulk silicon (in BSI) to maximize red response results in large crosstalk especially for blue light. In the second generation of these imagers, we undertook the exercise of solving the crosstalk problem by a two-pronged approach: a) an optimized epitaxial substrate that was engineered to maximize the internal electric field b) high aspect ratio trenches (30 μm deep) with carefully tailored sidewall passivation. The results show that the proposed optimizations are effective in curtailing crosstalk without having a major impact on other sensor parameters.

  10. X-ray imaging and spectroscopy using low cost COTS CMOS sensors

    NASA Astrophysics Data System (ADS)

    Lane, David W.

    2012-08-01

    Whilst commercial X-ray sensor arrays are capable of both imaging and spectroscopy they are currently expensive and this can limit their widespread use. This study examines the use of very low cost CMOS sensors for X-ray imaging and spectroscopy based on the commercial off the shelf (COTS) technology used in cellular telephones, PC multimedia and children's toys. Some examples of imaging using a 'webcam' and a modified OmniVision OV7411 sensor are presented, as well as a simple energy dispersive X-ray detector based on an OmniVision OV7221 sensor. In each case X-ray sensitivity was enabled by replacing the sensor's front glass window with a 5 μm thick aluminium foil, with X-rays detected as an increase in a pixel's dark current due to the generation of additional electron-hole pairs within its active region. The exposure control and data processing requirements for imaging and spectroscopy are discussed. The modified OV7221 sensor was found to have a linear X-ray energy calibration and a resolution of approximately 510 eV.

  11. Electronic radon monitoring with the CMOS System-on-Chip AlphaRad

    NASA Astrophysics Data System (ADS)

    Higueret, S.; Husson, D.; Le, T. D.; Nourreddine, A.; Michielsen, N.

    2008-01-01

    The development of the integrated circuit AlphaRad as a new System-on-Chip for detection of α-particles has already been reported. This paper deals with electronic monitoring of atmospheric radon, which is one of the promising applications of the chip. The future electronic radon monitor (ERM) is designed to be compact, inexpensive, operating at low voltage and fully stand-alone. We present here the complete electronic board of the future ERM: it is made of three independent AlphaRad chips running in parallel, mounted on a small printed-circuit board which includes a numeric block for data treatment based on a Xilinx programmable gate array. The maximal counting rate of the AlphaRad chip has been pushed to at least 3×10 6 α-particles cm -2. The complete system for detection of the solid aerosols will be published separately, and this paper will focus on the electronic board alone. Already 20 times faster than our first measurement with a CMOS pixel sensor, the system was tested at low and high activities, showing an excellent linearity for 222Rn levels up to 80 kBq m -3.

  12. From Pixels to Planets

    NASA Technical Reports Server (NTRS)

    Brownston, Lee; Jenkins, Jon M.

    2015-01-01

    The Kepler Mission was launched in 2009 as NASAs first mission capable of finding Earth-size planets in the habitable zone of Sun-like stars. Its telescope consists of a 1.5-m primary mirror and a 0.95-m aperture. The 42 charge-coupled devices in its focal plane are read out every half hour, compressed, and then downlinked monthly. After four years, the second of four reaction wheels failed, ending the original mission. Back on earth, the Science Operations Center developed the Science Pipeline to analyze about 200,000 target stars in Keplers field of view, looking for evidence of periodic dimming suggesting that one or more planets had crossed the face of its host star. The Pipeline comprises several steps, from pixel-level calibration, through noise and artifact removal, to detection of transit-like signals and the construction of a suite of diagnostic tests to guard against false positives. The Kepler Science Pipeline consists of a pipeline infrastructure written in the Java programming language, which marshals data input to and output from MATLAB applications that are executed as external processes. The pipeline modules, which underwent continuous development and refinement even after data started arriving, employ several analytic techniques, many developed for the Kepler Project. Because of the large number of targets, the large amount of data per target and the complexity of the pipeline algorithms, the processing demands are daunting. Some pipeline modules require days to weeks to process all of their targets, even when run on NASA's 128-node Pleiades supercomputer. The software developers are still seeking ways to increase the throughput. To date, the Kepler project has discovered more than 4000 planetary candidates, of which more than 1000 have been independently confirmed or validated to be exoplanets. Funding for this mission is provided by NASAs Science Mission Directorate.

  13. A 4MP high-dynamic-range, low-noise CMOS image sensor

    NASA Astrophysics Data System (ADS)

    Ma, Cheng; Liu, Yang; Li, Jing; Zhou, Quan; Chang, Yuchun; Wang, Xinyang

    2015-03-01

    In this paper we present a 4 Megapixel high dynamic range, low dark noise and dark current CMOS image sensor, which is ideal for high-end scientific and surveillance applications. The pixel design is based on a 4-T PPD structure. During the readout of the pixel array, signals are first amplified, and then feed to a low- power column-parallel ADC array which is already presented in [1]. Measurement results show that the sensor achieves a dynamic range of 96dB, a dark noise of 1.47e- at 24fps speed. The dark current is 0.15e-/pixel/s at -20oC.

  14. Illumination robust change detection with CMOS imaging sensors

    NASA Astrophysics Data System (ADS)

    Rengarajan, Vijay; Gupta, Sheetal B.; Rajagopalan, A. N.; Seetharaman, Guna

    2015-05-01

    Change detection between two images in the presence of degradations is an important problem in the computer vision community, more so for the aerial scenario which is particularly challenging. Cameras mounted on moving platforms such as aircrafts or drones are subject to general six-dimensional motion as the motion is not restricted to a single plane. With CMOS cameras increasingly in vogue due to their low power consumption, the inevitability of rolling-shutter (RS) effect adds to the challenge. This is caused by sequential exposure of rows in CMOS cameras unlike conventional global shutter cameras where all pixels are exposed simultaneously. The RS effect is particularly pronounced in aerial imaging since each row of the imaging sensor is likely to experience a different motion. For fast-moving platforms, the problem is further compounded since the rows are also affected by motion blur. Moreover, since the two images are shot at different times, illumination differences are common. In this paper, we propose a unified computational framework that elegantly exploits the scarcity constraint to deal with the problem of change detection in images degraded by RS effect, motion blur as well as non-global illumination differences. We formulate an optimization problem where each row of the distorted image is approximated as a weighted sum of the corresponding rows in warped versions of the reference image due to camera motion within the exposure period to account for geometric as well as photometric differences. The method has been validated on both synthetic and real data.

  15. CMOS low data rate imaging method based on compressed sensing

    NASA Astrophysics Data System (ADS)

    Xiao, Long-long; Liu, Kun; Han, Da-peng

    2012-07-01

    Complementary metal-oxide semiconductor (CMOS) technology enables the integration of image sensing and image compression processing, making improvements on overall system performance possible. We present a CMOS low data rate imaging approach by implementing compressed sensing (CS). On the basis of the CS framework, the image sensor projects the image onto a separable two-dimensional (2D) basis set and measures the corresponding coefficients obtained. First, the electrical current output from the pixels in a column are combined, with weights specified by voltage, in accordance with Kirchhoff's law. The second computation is performed in an analog vector-matrix multiplier (VMM). Each element of the VMM considers the total value of each column as the input and multiplies it by a unique coefficient. Both weights and coefficients are reprogrammable through analog floating-gate (FG) transistors. The image can be recovered from a percentage of these measurements using an optimization algorithm. The percentage, which can be altered flexibly by programming on the hardware circuit, determines the image compression ratio. These novel designs facilitate image compression during the image-capture phase before storage, and have the potential to reduce power consumption. Experimental results demonstrate that the proposed method achieves a large image compression ratio and ensures imaging quality.

  16. Scanning probe lithography approach for beyond CMOS devices

    NASA Astrophysics Data System (ADS)

    Durrani, Zahid; Jones, Mervyn; Kaestner, Marcus; Hofer, Manuel; Guliyev, Elshad; Ahmad, Ahmad; Ivanov, Tzvetan; Zoellner, Jens-Peter; Rangelow, Ivo W.

    2013-03-01

    As present CMOS devices approach technological and physical limits at the sub-10 nm scale, a `beyond CMOS' information-processing technology is necessary for timescales beyond the semiconductor technology roadmap. This requires new approaches to logic and memory devices, and to associated lithographic processes. At the sub-5 nm scale, a technology platform based on a combination of high-resolution scanning probe lithography (SPL) and nano-imprint lithography (NIL) is regarded as a promising candidate for both resolution and high throughput production. The practical application of quantum-effect devices, such as room temperature single-electron and quantum-dot devices, then becomes feasible. This paper considers lithographic and device approaches to such a `single nanometer manufacturing' technology. We consider the application of scanning probes, capable of imaging, probing of material properties and lithography at the single nanometer scale. Modified scanning probes are used to pattern molecular glass based resist materials, where the small particle size (<1 nm) and mono-disperse nature leads to more uniform and smaller lithographic pixel size. We also review the current status of single-electron and quantum dot devices capable of room-temperature operation, and discuss the requirements for these devices with regards to practical application.

  17. A 4096-pixel MAPS detector used to investigate the single-electron distribution in a Young-Feynman two-slit interference experiment

    NASA Astrophysics Data System (ADS)

    Gabrielli, A.; Giorgi, F. M.; Semprini, N.; Villa, M.; Zoccoli, A.; Matteucci, G.; Pozzi, G.; Frabboni, S.; Gazzadi, G. C.

    2013-01-01

    A monolithic CMOS detector, made of 4096 active pixels developed for HEP collider experiments, has been used in the Young-Feynman two-slit experiment with single electrons. The experiment has been carried out by inserting two nanometric slits in a transmission electron microscope that provided the electron beam source and the electro-optical lenses for projecting and focusing the interference pattern on the sensor. The fast readout of the sensor, in principle capable to manage up to 106 frames per second, allowed to record single-electron frames spaced by several empty frames. In this way, for the first time in a single-electron two-slit experiment, the time distribution of electron arrivals has been measured with a resolution of 165 μs. In addition, high statistics samples of single-electron events were collected within a time interval short enough to be compatible with the stability of the system and coherence conditions of the illumination.

  18. Photocurrent estimation from multiple nondestructive samples in CMOS image sensor

    NASA Astrophysics Data System (ADS)

    Liu, Xinqiao; El Gamal, Abbas

    2001-05-01

    CMOS image sensors generally suffer form lower dynamic range than CCDs due to their higher readout noise. Their high speed readout capability and the potential of integrating memory and signal processing with the sensor on the same chip, open up many possibilities for enhancing their dynamic range. Earlier work have demonstrated the use of multiple non-destructive samples to enhance dynamic range, while achieving higher SNR than using other dynamic range enhancement schemes. The high dynamic range image is constructed by appropriately scaling each pixel's last sample before saturation. Conventional CDS is used to reduce offset FPN and reset noise. This simple high dynamic range image construction scheme, however, does not take full advantage of the multiple samples. Readout noise power, which doubles as a result of performing CDS, remain as high as in conventional sensor operation. As a result dynamic range is only extended at the high illumination end. The paper explores the use of linear mean-square-error estimation to more fully exploit the multiple pixel samples to reduce readout noise and thus extend dynamic range at the low illumination end. We present three estimation algorithms: (1) a recursive estimator when reset noise and offset FPN are ignored, (2) a non-recursive algorithm when reset noise and FPN are considered, and (3) a recursive estimation algorithm for case (2), which achieves mean square error close to the non-recursive algorithm without the need to store all the samples. The later recursive algorithm is attractive since it requires the storage of only a few pixel values per pixel, which makes its implementation in a single chip digital imaging system feasible.

  19. Pixel telescope test in STAR at RHIC

    NASA Astrophysics Data System (ADS)

    Sun, Xiangming; Szelezniak, Michal; Greiner, Leo; Matis, Howard; Vu, Chinh; Stezelberger, Thorsten; Wieman, Howard

    2007-10-01

    The STAR experiment at RHIC is designing a new inner vertex detector called the Heavy Flavor Tracker (HFT). The HFT's innermost two layers is called the PIXEL detector which uses Monolithic Active Pixel Sensor technology (MAPS). To test the MAPS technology, we just constructed and tested a telescope. The telescope uses a stack of three MIMOSTAR2 chips, Each MIMOSTAR2 sensor, which was designed by IPHC, is an array of 132x128 pixels with a square pixel size of 30 μ. The readout of the telescope makes use of the ALICE DDL/SIU cards, which is compatible with the future STAR data acquisition system called DAQ1000. The telescope was first studied in a 1.2 GeV/c electron beam at LBNL's Advanced Light Source. Afterwards, the telescope was outside the STAR magnet, and then later inside it, 145 cm away from STAR's center. We will describe this first test of MAPS technology in a collider environment, and report on the occupancy, particle flux, and performance of the telescope.

  20. Front-end intelligence for triggering and local track measurement in gaseous pixel detectors

    NASA Astrophysics Data System (ADS)

    Gromov, V.; Hessey, N.; Vermeulen, J.

    2012-11-01

    A number of applications in high-energy physics and medicine requires three-dimensional reconstruction of the particle trajectories: for example, high momentum particles in accelerator-based experiments can be identified on the basis of the properties of their tracks, while in proton computed tomography accurate knowledge of the incoming and outgoing beam trajectory is crucial in reconstructing the most probable path of the proton traversing the patient. In this work we investigate the potential of Gaseous Pixel (GridPix) detectors for fast and efficient recognition of tracks and determination of their properties. This includes selection, without external trigger, of tracks with desired angles, for example tracks with small tilt angles corresponding to high momentum particles in a magnetic field. Being able to select these fast and without external input is of interest for the future upgrades of the LHC detectors. In this paper we present a track selection algorithm, and its physical implementation in 130 nm CMOS technology with estimates of power consumption, data rates, latency, and chip area. The Timepix3 chip, currently being designed for a wide range of applications, will also be suitable for readout of GridPix detectors. Both arrival time information (accuracy 1.6 ns) and charge deposit information will be delivered for each hit together with the coordinates of the active pixel. A short overview is presented of its architecture, which allows continuous self-triggered readout of sparsely distributed data with a rate up to 20 × 106 hits cm-2sec-1. The addition of fast track pattern recognition logic to TimePix3 in a successor chip is currently being investigated.

  1. The dual-gain 10 μm back-thinned 3k×3k CMOS-APS detector of the solar orbiter extreme UV imager

    NASA Astrophysics Data System (ADS)

    Halain, J.-P.; Debaize, A.; Gillis, J.-M.; Jacques, L.; De Ridder, T.; Hermans, L.; Koch, M.; Meynants, G.; Schippers, G.

    2014-07-01

    The Extreme Ultraviolet Imager (EUI) on-board the Solar Orbiter mission will provide image sequences of the solar atmosphere at selected spectral emission lines in the extreme and vacuum ultraviolet. For the two Extreme Ultraviolet (EUV) channels of the EUI instrument, low noise and radiation tolerant detectors with low power consumption and high sensitivity in the 10-40 nm wavelength range are required to achieve the science objectives. In that frame, a dual-gain 10 μm pixel pitch back-thinned 1k x 1k Active Pixel Sensor (APS) CMOS prototype has been tested during the preliminary development phase of the instrument, to validate the pixel design, the expected EUV sensitivity and noise level, and the capability to withstand the mission radiation environment. Taking heritage of this prototype, the detector architecture has been improved and scaled up to the required 3k x 3k array. The dynamic range is increased, the readout architecture enhanced, the power consumption reduced, and the pixel design adapted to the required stitching. The detector packaging has also been customized to fit within the constraints imposed by the camera mechanical, thermal and electrical boundaries. The manufacturing process has also been adapted and back-thinning process improved. Once manufactured and packaged, a batch of sensors will undergo a characterization and calibration campaign to select the best candidates for integration into the instrument qualification and flight cameras. The flight devices, within their cameras, will then be embarked on the EUI instrument, and be the first scientific APSCMOS detectors for EUV observation of the Sun.

  2. A 10-bit column-parallel cyclic ADC for high-speed CMOS image sensors

    NASA Astrophysics Data System (ADS)

    Ye, Han; Quanliang, Li; Cong, Shi; Nanjian, Wu

    2013-08-01

    This paper presents a high-speed column-parallel cyclic analog-to-digital converter (ADC) for a CMOS image sensor. A correlated double sampling (CDS) circuit is integrated in the ADC, which avoids a stand-alone CDS circuit block. An offset cancellation technique is also introduced, which reduces the column fixed-pattern noise (FPN) effectively. One single channel ADC with an area less than 0.02 mm2 was implemented in a 0.13 μm CMOS image sensor process. The resolution of the proposed ADC is 10-bit, and the conversion rate is 1.6 MS/s. The measured differential nonlinearity and integral nonlinearity are 0.89 LSB and 6.2 LSB together with CDS, respectively. The power consumption from 3.3 V supply is only 0.66 mW. An array of 48 10-bit column-parallel cyclic ADCs was integrated into an array of CMOS image sensor pixels. The measured results indicated that the ADC circuit is suitable for high-speed CMOS image sensors.

  3. Local Pixel Bundles: Bringing the Pixels to the People

    NASA Astrophysics Data System (ADS)

    Anderson, Jay

    2014-12-01

    The automated galaxy-based alignment software package developed for the Frontier Fields program (hst2galign, see Anderson & Ogaz 2014 and http://www.stsci.edu/hst/campaigns/frontier-fields/) produces a direct mapping from the pixels of the flt frame of each science exposure into a common master frame. We can use these mappings to extract the flt-pixels in the vicinity of a source of interest and package them into a convenient "bundle". In addition to the pixels, this data bundle can also contain "meta" information that will allow users to transform positions from the flt pixels to the reference frame and vice-versa. Since the un-resampled pixels in the flt frames are the only true constraints we have on the astronomical scene, the ability to inter-relate these pixels will enable many high-precision studies, such as: point-source-fitting and deconvolution with accurate PSFs, easy exploration of different image-combining algorithms, and accurate faint-source finding and photometry. The data products introduced in this ISR are a very early attempt to provide the flt-level pixel constraints in a package that is accessible to more than the handful of experts in HST astrometry. The hope is that users in the community might begin using them and will provide feedback as to what information they might want to see in the bundles and what general analysis packages they might find useful. For that reason, this document is somewhat informally written, since I know that it will be modified and updated as the products and tools are optimized.

  4. A SPAD-based 3D imager with in-pixel TDC for 145ps-accuracy ToF measurement

    NASA Astrophysics Data System (ADS)

    Vornicu, I.; Carmona-Galán, R.; Rodríguez-Vázquez, Á.

    2015-03-01

    The design and measurements of a CMOS 64 × 64 Single-Photon Avalanche-Diode (SPAD) array with in-pixel Time-to-Digital Converter (TDC) are presented. This paper thoroughly describes the imager at architectural and circuit level with particular emphasis on the characterization of the SPAD-detector ensemble. It is aimed to 2D imaging and 3D image reconstruction in low light environments. It has been fabricated in a standard 0.18μm CMOS process, i. e. without high voltage or low noise features. In these circumstances, we are facing a high number of dark counts and low photon detection efficiency. Several techniques have been applied to ensure proper functionality, namely: i) time-gated SPAD front-end with fast active-quenching/recharge circuit featuring tunable dead-time, ii) reverse start-stop scheme, iii) programmable time resolution of the TDC based on a novel pseudo-differential voltage controlled ring oscillator with fast start-up, iv) a global calibration scheme against temperature and process variation. Measurements results of individual SPAD-TDC ensemble jitter, array uniformity and time resolution programmability are also provided.

  5. Towards a new generation of pixel detector readout chips

    NASA Astrophysics Data System (ADS)

    Campbell, M.; Alozy, J.; Ballabriga, R.; Frojdh, E.; Heijne, E.; Llopart, X.; Poikela, T.; Tlustos, L.; Valerio, P.; Wong, W.

    2016-01-01

    The Medipix3 Collaboration has broken new ground in spectroscopic X-ray imaging and in single particle detection and tracking. This paper will review briefly the performance and limitations of the present generation of pixel detector readout chips developed by the Collaboration. Through Silicon Via technology has the potential to provide a significant improvement in the tile-ability and more flexibility in the choice of readout architecture. This has been explored in the context of 3 projects with CEA-LETI using Medipix3 and Timepix3 wafers. The next generation of chips will aim to provide improved spectroscopic imaging performance at rates compatible with human CT. It will also aim to provide full spectroscopic images with unprecedented energy and spatial resolution. Some of the opportunities and challenges posed by moving to a more dense CMOS process will be discussed.

  6. Accelerated life testing effects on CMOS microcircuit characteristics, phase 1

    NASA Technical Reports Server (NTRS)

    Maximow, B.

    1976-01-01

    An accelerated life test of sufficient duration to generate a minimum of 50% cumulative failures in lots of CMOS devices was conducted to provide a basis for determining the consistency of activation energy at 250 C. An investigation was made to determine whether any thresholds were exceeded during the high temperature testing, which could trigger failure mechanisms unique to that temperature. The usefulness of the 250 C temperature test as a predictor of long term reliability was evaluated.

  7. Recent progress and development of a speedster-EXD: a new event-triggered hybrid CMOS x-ray detector

    NASA Astrophysics Data System (ADS)

    Griffith, Christopher V.; Falcone, Abraham D.; Prieskorn, Zachary R.; Burrows, David N.

    2015-08-01

    We present the characterization of a new event-driven X-ray hybrid CMOS detector developed by Penn State University in collaboration with Teledyne Imaging Sensors. Along with its low susceptibility to radiation damage, low power consumption, and fast readout time to avoid pile-up, the Speedster-EXD has been designed with the capability to limit its readout to only those pixels containing charge, thus enabling even faster effective frame rates. The threshold for the comparator in each pixel can be set by the user so that only pixels with signal above the set threshold are read out. The Speedster-EXD hybrid CMOS detector also has two new in-pixel features that reduce noise from known noise sources: (1) a low-noise, high-gain CTIA amplifier to eliminate crosstalk from interpixel capacitance (IPC) and (2) in-pixel CDS subtraction to reduce kTC noise. We present the read noise, dark current, IPC, energy resolution, and gain variation measurements of one Speedster-EXD detector.

  8. X-ray characterization of a multichannel smart-pixel array detector.

    PubMed

    Ross, Steve; Haji-Sheikh, Michael; Huntington, Andrew; Kline, David; Lee, Adam; Li, Yuelin; Rhee, Jehyuk; Tarpley, Mary; Walko, Donald A; Westberg, Gregg; Williams, George; Zou, Haifeng; Landahl, Eric

    2016-01-01

    The Voxtel VX-798 is a prototype X-ray pixel array detector (PAD) featuring a silicon sensor photodiode array of 48 × 48 pixels, each 130 µm × 130 µm × 520 µm thick, coupled to a CMOS readout application specific integrated circuit (ASIC). The first synchrotron X-ray characterization of this detector is presented, and its ability to selectively count individual X-rays within two independent arrival time windows, a programmable energy range, and localized to a single pixel is demonstrated. During our first trial run at Argonne National Laboratory's Advance Photon Source, the detector achieved a 60 ns gating time and 700 eV full width at half-maximum energy resolution in agreement with design parameters. Each pixel of the PAD holds two independent digital counters, and the discriminator for X-ray energy features both an upper and lower threshold to window the energy of interest discarding unwanted background. This smart-pixel technology allows energy and time resolution to be set and optimized in software. It is found that the detector linearity follows an isolated dead-time model, implying that megahertz count rates should be possible in each pixel. Measurement of the line and point spread functions showed negligible spatial blurring. When combined with the timing structure of the synchrotron storage ring, it is demonstrated that the area detector can perform both picosecond time-resolved X-ray diffraction and fluorescence spectroscopy measurements. PMID:26698064

  9. Fast Imaging Detector Readout Circuits with In-Pixel ADCs for Fourier Transform Imaging Spectrometers

    NASA Technical Reports Server (NTRS)

    Rider, D.; Blavier, J-F.; Cunningham, T.; Hancock, B.; Key, R.; Pannell, Z.; Sander, S.; Seshadri, S.; Sun, C.; Wrigley, C.

    2011-01-01

    Focal plane arrays (FPAs) with high frame rates and many pixels benefit several upcoming Earth science missions including GEO-CAPE, GACM, and ACE by enabling broader spatial coverage and higher spectral resolution. FPAs for the PanFTS, a high spatial resolution Fourier transform spectrometer and a candidate instrument for the GEO-CAPE mission are the focus of the developments reported here, but this FPA technology has the potential to enable a variety of future measurements and instruments. The ESTO ACT Program funded the developed of a fast readout integrated circuit (ROIC) based on an innovative in-pixel analog-to-digital converter (ADC). The 128 X 128 pixel ROIC features 60 ?m pixels, a 14-bit ADC in each pixel and operates at a continuous frame rate of 14 kHz consuming only 1.1 W of power. The ROIC outputs digitized data completely eliminating the bulky, power consuming signal chains needed by conventional FPAs. The 128 X 128 pixel ROIC has been fabricated in CMOS and tested at the Jet Propulsion Laboratory. The current version is designed to be hybridized with PIN photodiode arrays via indium bump bonding for light detection in the visible and ultraviolet spectral regions. However, the ROIC design incorporates a small photodiode in each cell to permit detailed characterization of the ROICperformance without the need for hybridization. We will describe the essential features of the ROIC design and present results of ROIC performance measurements.

  10. X-ray Characterization of a Multichannel Smart-Pixel Array Detector

    SciTech Connect

    Ross, Steve; Haji-Sheikh, Michael; Huntington, Andrew; Kline, David; Lee, Adam; Li, Yuelin; Rhee, Jehyuk; Tarpley, Mary; Walko, Donald A.; Westberg, Gregg; Williams, George; Zou, Haifeng; Landahl, Eric

    2016-01-01

    The Voxtel VX-798 is a prototype X-ray pixel array detector (PAD) featuring a silicon sensor photodiode array of 48 x 48 pixels, each 130 mu m x 130 mu m x 520 mu m thick, coupled to a CMOS readout application specific integrated circuit (ASIC). The first synchrotron X-ray characterization of this detector is presented, and its ability to selectively count individual X-rays within two independent arrival time windows, a programmable energy range, and localized to a single pixel is demonstrated. During our first trial run at Argonne National Laboratory's Advance Photon Source, the detector achieved a 60 ns gating time and 700 eV full width at half-maximum energy resolution in agreement with design parameters. Each pixel of the PAD holds two independent digital counters, and the discriminator for X-ray energy features both an upper and lower threshold to window the energy of interest discarding unwanted background. This smart-pixel technology allows energy and time resolution to be set and optimized in software. It is found that the detector linearity follows an isolated dead-time model, implying that megahertz count rates should be possible in each pixel. Measurement of the line and point spread functions showed negligible spatial blurring. When combined with the timing structure of the synchrotron storage ring, it is demonstrated that the area detector can perform both picosecond time-resolved X-ray diffraction and fluorescence spectroscopy measurements.

  11. Focal plane readout for 2-D LWIR application implemented with current mode background suppression per pixel

    NASA Astrophysics Data System (ADS)

    Woo, Doo Hyung; Kang, Sang Gu; Lee, Hee Chul

    2004-02-01

    In this paper, a readout technique involving current mode background suppression is studied for 2-dimensional infrared focal plane arrays (IR FPA"s). This technique has a current memory per pixel, and the suppression current can be optimized per pixel element. Capacitive transimpedende amplifier (CTIA) and feedback amplifier structure are adopted for input circuit and background suppression circuit, respectively. Feedback amplifier structure can minimize skimming error due to channel length modulation. The area size of the pixel circuit is generally limited in the case of 2-D application. So, the amplifier used in the CTIA input circuit adopts timesharing for background suppression. To further improve the area limitation, a half circuit of the CTIA is shared in row circuit out of the pixel array. Because of the leakage of the current memory, the skimming data of the current memory in the pixel array is stored in SRAM array through ADC, and is refreshed periodically with SRAM data through DAC. The readout circuit was fabricated using 0.6um 2-poly 3-metal CMOS process for 64 x 64 LWIR HgCdTe IR array with the pixel size of 50um x 50um. The measurement performance of the skimming circuit exhibits about only 3% error for 100nA background current. The simulation results exhibit that skimming error can be reduced further to 0.3% when the ratioed current mirror scheme and/or multi step refresh scheme is adopted.

  12. Readout circuit design of the retina-like CMOS image sensor

    NASA Astrophysics Data System (ADS)

    Cao, Fengmei; Song, Shengyu; Bai, Tingzhu; Cao, Nan

    2015-02-01

    Readout circuit is designed for a special retina-like CMOS image sensor. To realize the pixels timing drive and readout of the sensor, the Altera's Cyclone II FPGA is used as a control chip. The voltage of the sensor is supported by a voltage chip initialized by SPI with AVR MCU system. The analog image signal outputted by the sensor is converted to digital image data by 12-bits A/D converter ADS807 and the digital data is memorized in the SRAM. Using the Camera-link image grabber, the data stored in SRAM is transformed to image shown on PC. Experimental results show the circuit works well on retina-like CMOS timing drive and image readout and images can be displayed properly on the PC.

  13. IR CMOS: the digital nightvision solution to sub-1 mLux imaging

    NASA Astrophysics Data System (ADS)

    Pralle, M. U.; Carey, J. E.; Vineis, C.; Palsule, C.; Jiang, J.; Joy, T.

    2015-05-01

    SiOnyx has demonstrated imaging at light levels below 1 mLux at 60 FPS with a 720P CMOS image sensor in a compact, low latency camera. The camera contains a 1 inch (16 mm) optical format sensor and streams uncompressed video over CameraLink with row wise image latency below 1 msec. Sub mLux imaging is enabled by the combination of enhanced quantum efficiency in the near infrared together with state of the art low noise image sensor design. The quantum efficiency enhancement is achieved by utilizing SiOnyx's proprietary ultrafast laser semiconductor processing technology that enhances the absorption of light within a thin pixel layer. Our technology demonstrates a 10 fold improvement in infrared sensitivity over incumbent imaging technology while maintaining complete compatibility with standard CMOS image sensor process flows. Applications include surveillance, nightvision, and 1064nm laser see-spot.

  14. Novel low area CMOS readout circuit for uncooled microbolometers with low noise

    NASA Astrophysics Data System (ADS)

    Lv, Jian; Jiang, Yadong; Zhou, Yun; Luo, Fengwu

    2009-05-01

    We propose a novel CMOS readout structure without sample and hold (SH) circuit for uncooled microbolometers. In this readout circuit, all the pixels in one row can be integrated simultaneously, and the readout integrated circuit (ROIC) area can be reduced by as much as 30%. Moreover, a single capacitor implementation of both capacitive transimpedance amplifier (CTIA) and correlated double sampling (CDS) is utilized to improve noise performance. An experimental 40x30 ROIC chip has been designed and fabricated with 0.5 μm CMOS technology. The test results show that the ROIC has good linearity with 260μV RMS total output noise voltage and 1800x650 μm2 total circuit area.

  15. Method of fabrication of display pixels driven by silicon thin film transistors

    DOEpatents

    Carey, Paul G.; Smith, Patrick M.

    1999-01-01

    Display pixels driven by silicon thin film transistors are fabricated on plastic substrates for use in active matrix displays, such as flat panel displays. The process for forming the pixels involves a prior method for forming individual silicon thin film transistors on low-temperature plastic substrates. Low-temperature substrates are generally considered as being incapable of withstanding sustained processing temperatures greater than about 200.degree. C. The pixel formation process results in a complete pixel and active matrix pixel array. A pixel (or picture element) in an active matrix display consists of a silicon thin film transistor (TFT) and a large electrode, which may control a liquid crystal light valve, an emissive material (such as a light emitting diode or LED), or some other light emitting or attenuating material. The pixels can be connected in arrays wherein rows of pixels contain common gate electrodes and columns of pixels contain common drain electrodes. The source electrode of each pixel TFT is connected to its pixel electrode, and is electrically isolated from every other circuit element in the pixel array.

  16. Performance analysis of a large photoactive area CMOS line sensor for fast, time-resolved spectroscopy applications

    NASA Astrophysics Data System (ADS)

    Poklonskaya, Elena A.; Durini, Daniel; Jung, Melanie; Schrey, Olaf; Driewer, Adrian; Brockherde, Werner; Hosticka, Bedrich; Vogt, Holger

    2014-05-01

    The performance of a fabricated CMOS line sensor based on the lateral drift-field photodiode (LDPD)1 concept is described. A new pixel structure was designed to decrease the charge transfer time across the photoactive area. Synopsys TCAD simulations were performed to design a proper intrinsic lateral drift-field within the pixel. The line sensor was fabricated in the 0.35 μm CMOS technology, and further characterized using a tailored photon-transfer method2 and the EMVA 1288 standard3. The basic parameters such as spectral responsivity, photo-response non-uniformity and dark current were measured at fabricated sensor samples. A special attention was paid to charge transfer time characterization4 and the evaluation of crosstalk between neighboring pixels - two major concerns attained during the development. It is shown that the electro-optical characteristics of the developed line sensor are comparable to those delivered by CCD line sensors available on the market, which are normally superior in performance compared to their CMOS based counterparts, but offering additional features such as the possibility of time gating, non-destructive readout, and charge accumulation over several cycles: approaches used to enhance the signal-to-noise ratio (SNR) of the sensor output.

  17. High-speed CMOS image sensor for high-throughput lensless microfluidic imaging system

    NASA Astrophysics Data System (ADS)

    Yan, Mei; Huang, Xiwei; Jia, Qixiang; Nadipalli, Revanth; Wang, Tongxi; Shang, Yang; Yu, Hao; Je, Minkyu; Yeo, Kiatseng

    2012-03-01

    The integration of CMOS image sensor and microfluidics becomes a promising technology for point-of-care (POC) diagnosis. However, commercial image sensors usually have limited speed and low-light sensitivity. One high-speed and high-sensitivity CMOS image sensor chip is introduced in this paper, targeted for high-throughput microfluidic imaging system. Firstly, high speed image sensor architecture is introduced with design of column-parallel single-slope analog-todigital converter (ADC) with digital correlated double sampling (CDS). The frame rate can be achieved to 2400 frames/second (fps) with resolution of 128×96 for high-throughput microfluidic imaging. Secondly, the designed system has superior low-light sensitivity, which is achieved by large pixel size (10μm×10μm, 56% fill factor). Pixel peak signalnoise- ratio (SNR) reaches to 50dB with 10dB improvement compared to the commercial pixel (2.2μm×2.2μm). The degradation of pixel resolution is compensated by super-resolution image processing algorithm. By reconstructing single image with multiple low-resolution frames, we can equivalently achieve 2μm resolution with physical 10μm pixel. Thirdly, the system-on-chip (SoC) integration results in a real-time controlled intelligent imaging system without expensive data storage and time-consuming computer analysis. This initial sensor prototype with timing-control makes it possible to develop high-throughput lensless microfluidic imaging system for POC diagnosis.

  18. Commercial CMOS image sensors as X-ray imagers and particle beam monitors

    NASA Astrophysics Data System (ADS)

    Castoldi, A.; Guazzoni, C.; Maffessanti, S.; Montemurro, G. V.; Carraresi, L.

    2015-01-01

    CMOS image sensors are widely used in several applications such as mobile handsets webcams and digital cameras among others. Furthermore they are available across a wide range of resolutions with excellent spectral and chromatic responses. In order to fulfill the need of cheap systems as beam monitors and high resolution image sensors for scientific applications we exploited the possibility of using commercial CMOS image sensors as X-rays and proton detectors. Two different sensors have been mounted and tested. An Aptina MT9v034, featuring 752 × 480 pixels, 6μm × 6μm pixel size has been mounted and successfully tested as bi-dimensional beam profile monitor, able to take pictures of the incoming proton bunches at the DeFEL beamline (1-6 MeV pulsed proton beam) of the LaBeC of INFN in Florence. The naked sensor is able to successfully detect the interactions of the single protons. The sensor point-spread-function (PSF) has been qualified with 1MeV protons and is equal to one pixel (6 mm) r.m.s. in both directions. A second sensor MT9M032, featuring 1472 × 1096 pixels, 2.2 × 2.2 μm pixel size has been mounted on a dedicated board as high-resolution imager to be used in X-ray imaging experiments with table-top generators. In order to ease and simplify the data transfer and the image acquisition the system is controlled by a dedicated micro-processor board (DM3730 1GHz SoC ARM Cortex-A8) on which a modified LINUX kernel has been implemented. The paper presents the architecture of the sensor systems and the results of the experimental measurements.

  19. High speed wide field CMOS camera for Transneptunian Automatic Occultation Survey

    NASA Astrophysics Data System (ADS)

    Wang, Shiang-Yu; Geary, John C.; Amato, Stephen M.; Hu, Yen-Sang; Ling, Hung-Hsu; Huang, Pin-Jie; Furesz, Gabor; Chen, Hsin-Yo; Chang, Yin-Chang; Szentgyorgyi, Andrew; Lehner, Matthew; Norton, Timothy

    2014-08-01

    The Transneptunian Automated Occultation Survey (TAOS II) is a three robotic telescope project to detect the stellar occultation events generated by Trans Neptunian Objects (TNOs). TAOS II project aims to monitor about 10000 stars simultaneously at 20Hz to enable statistically significant event rate. The TAOS II camera is designed to cover the 1.7 degree diameter field of view (FoV) of the 1.3m telescope with 10 mosaic 4.5kx2k CMOS sensors. The new CMOS sensor has a back illumination thinned structure and high sensitivity to provide similar performance to that of the backillumination thinned CCDs. The sensor provides two parallel and eight serial decoders so the region of interests can be addressed and read out separately through different output channels efficiently. The pixel scale is about 0.6"/pix with the 16μm pixels. The sensors, mounted on a single Invar plate, are cooled to the operation temperature of about 200K by a cryogenic cooler. The Invar plate is connected to the dewar body through a supporting ring with three G10 bipods. The deformation of the cold plate is less than 10μm to ensure the sensor surface is always within ±40μm of focus range. The control electronics consists of analog part and a Xilinx FPGA based digital circuit. For each field star, 8×8 pixels box will be readout. The pixel rate for each channel is about 1Mpix/s and the total pixel rate for each camera is about 80Mpix/s. The FPGA module will calculate the total flux and also the centroid coordinates for every field star in each exposure.

  20. Comparative study of a wireless digital system and 2 PSP digital systems on proximal caries detection and pixel values.

    PubMed

    dos Anjos Pontual, Andrea; de Melo, Daniela Pita; Pontual, Maria Luiza dos Anjos; de Almeida, Solange Maria; Haiter-Neto, Francisco

    2013-01-01

    This study compared the radiographic image quality of 2 photostimulable phosphor (PSP) plate systems with a radiographic system against a complementary metal oxide silicon (CMOS) system. Using the 3 digital systems, 160 approximal surfaces were radiographed under standardized conditions. Using a 5-point scale, 6 observers scored the resulting images for the presence of caries. The presence of caries was validated histologically, and the image receptors were evaluated using receiver operating characteristic curve analysis. The digital systems were used to take radiographs of an aluminum step wedge for objective analysis with pixel density measurements. The mean pixel values were analyzed statistically using the Kruskal-Wallis test and Dunn multiple comparison test (P < 0.01). The performance of the new CMOS system was comparable to the PSP plate systems and radiographic film. PMID:24064165

  1. A fully integrated CMOS inverse sine circuit for computational systems

    NASA Astrophysics Data System (ADS)

    Seon, Jong-Kug

    2010-08-01

    An inverse trigonometric function generator using CMOS technology is presented and implemented. The development and synthesis of inverse trigonometric functional circuits based on the simple approximation equations are also introduced. The proposed inverse sine function generator has the infinite input range and can be used in many measurement and instrumentation systems. The nonlinearity of less than 2.8% for the entire input range of 0.5 Vp-p with a small-signal bandwidth of 3.2 MHz is achieved. The chip implemented in 0.25 μm CMOS process operates from a single 1.8 V supply. The measured power consumption and the active chip area of the inverse sine function circuit are 350 μW and 0.15 mm2, respectively.

  2. Monolithic CMOS-MEMS integration for high-g accelerometers

    NASA Astrophysics Data System (ADS)

    Narasimhan, Vinayak; Li, Holden; Tan, Chuan Seng

    2014-10-01

    This paper highlights work-in-progress towards the conceptualization, simulation, fabrication and initial testing of a silicon-germanium (SiGe) integrated CMOS-MEMS high-g accelerometer for military, munition, fuze and shock measurement applications. Developed on IMEC's SiGe MEMS platform, the MEMS offers a dynamic range of 5,000 g and a bandwidth of 12 kHz. The low noise readout circuit adopts a chopper-stabilization technique implementing the CMOS through the TSMC 0.18 µm process. The device structure employs a fully differential split comb-drive set up with two sets of stators and a rotor all driven separately. Dummy structures acting as protective over-range stops were designed to protect the active components when under impacts well above the designed dynamic range.

  3. Carbon Nanotube Integration with a CMOS Process

    PubMed Central

    Perez, Maximiliano S.; Lerner, Betiana; Resasco, Daniel E.; Pareja Obregon, Pablo D.; Julian, Pedro M.; Mandolesi, Pablo S.; Buffa, Fabian A.; Boselli, Alfredo; Lamagna, Alberto

    2010-01-01

    This work shows the integration of a sensor based on carbon nanotubes using CMOS technology. A chip sensor (CS) was designed and manufactured using a 0.30 μm CMOS process, leaving a free window on the passivation layer that allowed the deposition of SWCNTs over the electrodes. We successfully investigated with the CS the effect of humidity and temperature on the electrical transport properties of SWCNTs. The possibility of a large scale integration of SWCNTs with CMOS process opens a new route in the design of more efficient, low cost sensors with high reproducibility in their manufacture. PMID:22319330

  4. Pixel front-end with synchronous discriminator and fast charge measurement for the upgrades of HL-LHC experiments

    NASA Astrophysics Data System (ADS)

    Monteil, E.; Demaria, N.; Pacher, L.; Rivetti, A.; Da Rocha Rolo, M.; Rotondo, F.; Leng, C.

    2016-03-01

    The upgrade of the silicon pixel sensors for the HL-LHC experiments requires the development of new readout integrated circuits due to unprecedented radiation levels, very high hit rates and increased pixel granularity. The design of a very compact, low power, low threshold analog very front-end in CMOS 65 nm technology is described. It contains a synchronous comparator which uses an offset compensation technique based on storing the offset in output. The latch can be turned into a local oscillator using an asynchronous logic feedback loop to implement a fast time-over-threshold counting. This design has been submitted and the measurement results are presented.

  5. The CMS pixel luminosity telescope

    NASA Astrophysics Data System (ADS)

    Kornmayer, A.

    2016-07-01

    The Pixel Luminosity Telescope (PLT) is a new complement to the CMS detector for the LHC Run II data taking period. It consists of eight 3-layer telescopes based on silicon pixel detectors that are placed around the beam pipe on each end of CMS viewing the interaction point at small angle. A fast 3-fold coincidence of the pixel planes in each telescope will provide a bunch-by-bunch measurement of the luminosity. Particle tracking allows collision products to be distinguished from beam background, provides a self-alignment of the detectors, and a continuous in-time monitoring of the efficiency of each telescope plane. The PLT is an independent luminometer, essential to enhance the robustness on the measurement of the delivered luminosity and to reduce its systematic uncertainties. This will allow to determine production cross-sections, and hence couplings, with high precision and to set more stringent limits on new particle production.

  6. Coherence experiments in single-pixel digital holography.

    PubMed

    Liu, Jung-Ping; Guo, Chia-Hao; Hsiao, Wei-Jen; Poon, Ting-Chung; Tsang, Peter

    2015-05-15

    In optical scanning holography (OSH), the coherence properties of the acquired holograms depend on the single-pixel size, i.e., the active area of the photodetector. For the first time, to the best of our knowledge, we have demonstrated coherent, partial coherent, and incoherent three-dimensional (3D) imaging by experiment in such a single-pixel digital holographic recording system. We have found, for the incoherent mode of OSH, in which the detector of the largest active area is applied, the 3D location of a diffusely reflecting object can be successfully retrieved without speckle noise. For the partial coherent mode employing a smaller pixel size of the detector, significant speckles and randomly distributed bright spots appear among the reconstructed images. For the coherent mode of OSH when the size of the pixel is vanishingly small, the bright spots disappear. However, the speckle remains and the signal-to-noise ratio is low. PMID:26393741

  7. Biosensing with integrated CMOS nanopores

    NASA Astrophysics Data System (ADS)

    Uddin, Ashfaque; Yemenicioglu, Sukru; Chen, Chin-Hsuan; Corgliano, Ellie; Milaninia, Kaveh; Xia, Fan; Plaxco, Kevin; Theogarajan, Luke

    2012-10-01

    This paper outlines our recent efforts in using solid-state nanopores as a biosensing platform. Traditionally biosensors concentrate mainly on the detection platform and not on signal processing. This decoupling can lead to inferior sensors and is exacerbated in nanoscale devices, where device noise is large and large dynamic range is required. This paper outlines a novel platform that integrates the nano, micro and macroscales in a closely coupled manner that mitigates many of these problems. We discuss our initial results of DNA translocation through the nanopore. We also briefly discuss the use of molecular recognition properties of aptamers with the versatility of the nanopore detector to design a new class of biosensors in a CMOS compatible platform.

  8. Few-Layer MoS2-Organic Thin-Film Hybrid Complementary Inverter Pixel Fabricated on a Glass Substrate.

    PubMed

    Lee, Hee Sung; Shin, Jae Min; Jeon, Pyo Jin; Lee, Junyeong; Kim, Jin Sung; Hwang, Hyun Chul; Park, Eunyoung; Yoon, Woojin; Ju, Sang-Yong; Im, Seongil

    2015-05-13

    Few-layer MoS2-organic thin-film hybrid complementary inverters demonstrate a great deal of device performance with a decent voltage gain of ≈12, a few hundred pW power consumption, and 480 Hz switching speed. As fabricated on glass, this hybrid CMOS inverter operates as a light-detecting pixel as well, using a thin MoS2 channel. PMID:25641643

  9. Zero suppression logic of the ALICE muon forward tracker pixel chip prototype PIXAM and associated readout electronics development

    NASA Astrophysics Data System (ADS)

    Flouzat, C.; Değerli, Y.; Guilloux, F.; Orsini, F.; Venault, P.

    2015-05-01

    In the framework of the ALICE experiment upgrade at HL-LHC, a new forward tracking detector, the Muon Forward Tracker (MFT), is foreseen to overcome the intrinsic limitations of the present Muon Spectrometer and will perform new measurements of general interest for the whole ALICE physics. To fulfill the new detector requirements, CMOS Monolithic Active Pixel Sensors (MAPS) provide an attractive trade-off between readout speed, spatial resolution, radiation hardness, granularity, power consumption and material budget. This technology has been chosen to equip the Muon Forward Tracker and also the vertex detector: the Inner Tracking System (ITS). Since few years, an intensive R&D program has been performed on the design of MAPS in the 0.18 μ m CMOS Image Sensor (CIS) process. In order to avoid pile up effects in the experiment, the classical rolling shutter readout system of MAPS has been improved to overcome the readout speed limitation. A zero suppression algorithm, based on a 3 by 3 cluster finding (position and data), has been chosen for the MFT. This algorithm allows adequate data compression for the sensor. This paper presents the large size prototype PIXAM, which represents 1/3 of the final chip, and will focus specially on the zero suppression block architecture. This chip is designed and under fabrication in the 0.18 μ m CIS process. Finally, the readout electronics principle to send out the compressed data flow is also presented taking into account the cluster occupancy per MFT plane for a single central Pb-Pb collision.

  10. Microradiography with Semiconductor Pixel Detectors

    NASA Astrophysics Data System (ADS)

    Jakubek, Jan; Cejnarova, Andrea; Dammer, Jiří; Holý, Tomáš; Platkevič, Michal; Pospíšil, Stanislav; Vavřík, Daniel; Vykydal, Zdeněk

    2007-11-01

    High resolution radiography (with X-rays, neutrons, heavy charged particles, …) often exploited also in tomographic mode to provide 3D images stands as a powerful imaging technique for instant and nondestructive visualization of fine internal structure of objects. Novel types of semiconductor single particle counting pixel detectors offer many advantages for radiation imaging: high detection efficiency, energy discrimination or direct energy measurement, noiseless digital integration (counting), high frame rate and virtually unlimited dynamic range. This article shows the application and potential of pixel detectors (such as Medipix2 or TimePix) in different fields of radiation imaging.

  11. Design and Fabrication of High-Efficiency CMOS/CCD Imagers

    NASA Technical Reports Server (NTRS)

    Pain, Bedabrata

    2007-01-01

    An architecture for back-illuminated complementary metal oxide/semiconductor (CMOS) and charge-coupled-device (CCD) ultraviolet/visible/near infrared- light image sensors, and a method of fabrication to implement the architecture, are undergoing development. The architecture and method are expected to enable realization of the full potential of back-illuminated CMOS/CCD imagers to perform with high efficiency, high sensitivity, excellent angular response, and in-pixel signal processing. The architecture and method are compatible with next-generation CMOS dielectric-forming and metallization techniques, and the process flow of the method is compatible with process flows typical of the manufacture of very-large-scale integrated (VLSI) circuits. The architecture and method overcome all obstacles that have hitherto prevented high-yield, low-cost fabrication of back-illuminated CMOS/CCD imagers by use of standard VLSI fabrication tools and techniques. It is not possible to discuss the obstacles in detail within the space available for this article. Briefly, the obstacles are posed by the problems of generating light-absorbing layers having desired uniform and accurate thicknesses, passivation of surfaces, forming structures for efficient collection of charge carriers, and wafer-scale thinning (in contradistinction to diescale thinning). A basic element of the present architecture and method - the element that, more than any other, makes it possible to overcome the obstacles - is the use of an alternative starting material: Instead of starting with a conventional bulk-CMOS wafer that consists of a p-doped epitaxial silicon layer grown on a heavily-p-doped silicon substrate, one starts with a special silicon-on-insulator (SOI) wafer that consists of a thermal oxide buried between a lightly p- or n-doped, thick silicon layer and a device silicon layer of appropriate thickness and doping. The thick silicon layer is used as a handle: that is, as a mechanical support for the

  12. Development of Gated Pinned Avalanche Photodiode Pixels for High-Speed Low-Light Imaging.

    PubMed

    Resetar, Tomislav; De Munck, Koen; Haspeslagh, Luc; Rosmeulen, Maarten; Süss, Andreas; Puers, Robert; Van Hoof, Chris

    2016-01-01

    This work explores the benefits of linear-mode avalanche photodiodes (APDs) in high-speed CMOS imaging as compared to different approaches present in literature. Analysis of APDs biased below their breakdown voltage employed in single-photon counting mode is also discussed, showing a potentially interesting alternative to existing Geiger-mode APDs. An overview of the recently presented gated pinned avalanche photodiode pixel concept is provided, as well as the first experimental results on a 8 × 16 pixel test array. Full feasibility of the proposed pixel concept is not demonstrated; however, informative data is obtained from the sensor operating under -32 V substrate bias and clearly exhibiting wavelength-dependent gain in frontside illumination. The readout of the chip designed in standard 130 nm CMOS technology shows no dependence on the high-voltage bias. Readout noise level of 15 e - rms, full well capacity of 8000 e - , and the conversion gain of 75 µV / e - are extracted from the photon-transfer measurements. The gain characteristics of the avalanche junction are characterized on separate test diodes showing a multiplication factor of 1.6 for red light in frontside illumination. PMID:27537882

  13. Single Photon Counting Performance and Noise Analysis of CMOS SPAD-Based Image Sensors.

    PubMed

    Dutton, Neale A W; Gyongy, Istvan; Parmesan, Luca; Henderson, Robert K

    2016-01-01

    SPAD-based solid state CMOS image sensors utilising analogue integrators have attained deep sub-electron read noise (DSERN) permitting single photon counting (SPC) imaging. A new method is proposed to determine the read noise in DSERN image sensors by evaluating the peak separation and width (PSW) of single photon peaks in a photon counting histogram (PCH). The technique is used to identify and analyse cumulative noise in analogue integrating SPC SPAD-based pixels. The DSERN of our SPAD image sensor is exploited to confirm recent multi-photon threshold quanta image sensor (QIS) theory. Finally, various single and multiple photon spatio-temporal oversampling techniques are reviewed. PMID:27447643

  14. Single Photon Counting Performance and Noise Analysis of CMOS SPAD-Based Image Sensors

    PubMed Central

    Dutton, Neale A. W.; Gyongy, Istvan; Parmesan, Luca; Henderson, Robert K.

    2016-01-01

    SPAD-based solid state CMOS image sensors utilising analogue integrators have attained deep sub-electron read noise (DSERN) permitting single photon counting (SPC) imaging. A new method is proposed to determine the read noise in DSERN image sensors by evaluating the peak separation and width (PSW) of single photon peaks in a photon counting histogram (PCH). The technique is used to identify and analyse cumulative noise in analogue integrating SPC SPAD-based pixels. The DSERN of our SPAD image sensor is exploited to confirm recent multi-photon threshold quanta image sensor (QIS) theory. Finally, various single and multiple photon spatio-temporal oversampling techniques are reviewed. PMID:27447643

  15. The pixel detector for the CMS phase-II upgrade

    NASA Astrophysics Data System (ADS)

    Dinardo, M. E.

    2015-04-01

    The high luminosity phase of the Large Hadron Collider (HL-LHC) requires a major pixel detector R&D effort to develop both readout chip and sensor that are capable to withstand unprecedented extremely high radiation. The target integrated luminosity of 3000 fb-1, that the HL-LHC is expected to deliver over about 10 years of operation, translates into a hadron fluence of 2×1016 1 MeV eq.n. / cm2, or equivalently 10 MGy of radiation dose in silicon, at about 3 cm from the interaction region where the first layer of the pixel detector could be located. The CMS collaboration has undertaken two baseline sensor R&D programs on thin n-on-p planar and 3D silicon sensor technologies. Together with the ATLAS collaboration it has also been established a common R&D effort for the development of the readout chip in the 65 nm CMOS technology. Status, progresses, and prospects of the CMS R&D effort are presented and discussed in this article.

  16. Design of ADC in 25 μm pixels pitch dedicated for IRFPA image processing at LETI

    NASA Astrophysics Data System (ADS)

    Tchagaspanian, M.; Villard, P.; Dupont, B.; Chammings, G.; Martin, J. L.; Pistre, C.; Lattard, D.; Chantre, C.; Arnaud, A.; Yon, J. J.; Simoens, F.; Tissot, J. L.

    2007-04-01

    LETI has been involved in IRFPA development since 1978, the design department (LETI/DCIS) has focused its work on new ROIC architecture since many years. The trend is to integrate advanced functions into the CMOS design in the aim of making cost efficient sensors. The purpose of this paper is to present the latest developments of an Analog to Digital Converter embedded in a 25μm pixel. The design is driven by several goals. It targets both long integration time and snapshot exposure, 100% of image frame time being available for integration. All pixels are integrating the IR signal at the same time. The IR signal is converted into digital by using a charge packet counter. High density 130nm CMOS allows to use many digital functions such as counting, memory and addressing. This new structure has been applied to 25μm pitch bolometer sensors with a dedicated 320 x 240 IRCMOS circuit. Due to smart image processing in the CMOS, the bolometer architecture requirements may become very simple and low cost. The room temperature sensitivity and the DC offset are solved directly in the pixel. This FPA targets low NETD (<50mK), a variation of 80 Kelvin for the FPA temperature, 14 bits output at 50/60Hz video rate.

  17. DynAMITe: a prototype large area CMOS APS for breast cancer diagnosis using x-ray diffraction measurements

    NASA Astrophysics Data System (ADS)

    Konstantinidis, A.; Anaxagoras, T.; Esposito, M.; Allinson, N.; Speller, R.

    2012-03-01

    X-ray diffraction studies are used to identify specific materials. Several laboratory-based x-ray diffraction studies were made for breast cancer diagnosis. Ideally a large area, low noise, linear and wide dynamic range digital x-ray detector is required to perform x-ray diffraction measurements. Recently, digital detectors based on Complementary Metal-Oxide- Semiconductor (CMOS) Active Pixel Sensor (APS) technology have been used in x-ray diffraction studies. Two APS detectors, namely Vanilla and Large Area Sensor (LAS), were developed by the Multidimensional Integrated Intelligent Imaging (MI-3) consortium to cover a range of scientific applications including x-ray diffraction. The MI-3 Plus consortium developed a novel large area APS, named as Dynamically Adjustable Medical Imaging Technology (DynAMITe), to combine the key characteristics of Vanilla and LAS with a number of extra features. The active area (12.8 × 13.1 cm2) of DynaMITe offers the ability of angle dispersive x-ray diffraction (ADXRD). The current study demonstrates the feasibility of using DynaMITe for breast cancer diagnosis by identifying six breast-equivalent plastics. Further work will be done to optimize the system in order to perform ADXRD for identification of suspicious areas of breast tissue following a conventional mammogram taken with the same sensor.

  18. Edge pixel response studies of edgeless silicon sensor technology for pixellated imaging detectors

    NASA Astrophysics Data System (ADS)

    Maneuski, D.; Bates, R.; Blue, A.; Buttar, C.; Doonan, K.; Eklund, L.; Gimenez, E. N.; Hynds, D.; Kachkanov, S.; Kalliopuska, J.; McMullen, T.; O'Shea, V.; Tartoni, N.; Plackett, R.; Vahanen, S.; Wraight, K.

    2015-03-01

    Silicon sensor technologies with reduced dead area at the sensor's perimeter are under development at a number of institutes. Several fabrication methods for sensors which are sensitive close to the physical edge of the device are under investigation utilising techniques such as active-edges, passivated edges and current-terminating rings. Such technologies offer the goal of a seamlessly tiled detection surface with minimum dead space between the individual modules. In order to quantify the performance of different geometries and different bulk and implant types, characterisation of several sensors fabricated using active-edge technology were performed at the B16 beam line of the Diamond Light Source. The sensors were fabricated by VTT and bump-bonded to Timepix ROICs. They were 100 and 200 μ m thick sensors, with the last pixel-to-edge distance of either 50 or 100 μ m. The sensors were fabricated as either n-on-n or n-on-p type devices. Using 15 keV monochromatic X-rays with a beam spot of 2.5 μ m, the performance at the outer edge and corners pixels of the sensors was evaluated at three bias voltages. The results indicate a significant change in the charge collection properties between the edge and 5th (up to 275 μ m) from edge pixel for the 200 μ m thick n-on-n sensor. The edge pixel performance of the 100 μ m thick n-on-p sensors is affected only for the last two pixels (up to 110 μ m) subject to biasing conditions. Imaging characteristics of all sensor types investigated are stable over time and the non-uniformities can be minimised by flat-field corrections. The results from the synchrotron tests combined with lab measurements are presented along with an explanation of the observed effects.

  19. Characterization of a CMOS detector for limited-view mammography

    NASA Astrophysics Data System (ADS)

    Elbakri, Idris A.

    2007-03-01

    Sensors based on complementary metal oxide semiconductors (CMOS) technology have recently been considered for mammography applications. CMOS offers the advantages of lower cost and relative ease of fabrications. We report on the evaluation of a CMOS imager (C9730DK, Hamamatsu Corporation) with 14-bit digitization and 50-micron detector element (del) resolution. The imager has an active area of 5 x 5 cm and uses 160-micron layer of needle-crystal CsI (55 mg/cc) to convert x-rays to light. The detector is suitable for spot and specimen imaging and image-guided biopsy. To evaluate resolution performance, we measured the modulation transfer function (MTF) using the slanted edge method. We also measured the normalized noise power spectrum (NNPS) using Fourier analysis of uniform images. The MTF and NNPS were used to determine the detective quantum efficiency (DQE) of the detector. The detector was characterized using a molybdenum target/molybdenum filter mammography x-ray source operated at 28 kVp with 44mm of PMMA added to mimic clinical beam quality (HVL = 0.62 mm Al). Our analysis showed that the imager had a linear response. The MTF was 28% at 5 lp/mm and 8% at 10 lp/mm. The product of the NNPS and exposure showed that the detector was quantum limited. The DQE near 0 lp/mm was in the 55-60% range. The DQE and MTF performance of the CMOS detector are comparable to published values for other digital mammography detectors.

  20. A 65k pixel, 150k frames-per-second camera with global gating and micro-lenses suitable for fluorescence lifetime imaging

    NASA Astrophysics Data System (ADS)

    Burri, Samuel; Powolny, François; Bruschini, Claudio E.; Michalet, Xavier; Regazzoni, Francesco; Charbon, Edoardo

    2014-05-01

    This paper presents our work on a 65k pixel single-photon avalanche diode (SPAD) based imaging sensor realized in a 0.35μm standard CMOS process. At a resolution of 512 by 128 pixels the sensor is read out in 6.4μs to deliver over 150k monochrome frames per second. The individual pixel has a size of 24μm2 and contains the SPAD with a 12T quenching and gating circuitry along with a memory element. The gating signals are distributed across the chip through a balanced tree to minimize the signal skew between the pixels. The array of pixels is row-addressable and data is sent out of the chip on 128 lines in parallel at a frequency of 80MHz. The system is controlled by an FPGA which generates the gating and readout signals and can be used for arbitrary real-time computation on the frames from the sensor. The communication protocol between the camera and a conventional PC is USB2. The active area of the chip is 5% and can be significantly improved with the application of a micro-lens array. A micro-lens array, for use with collimated light, has been designed and its performance is reviewed in the paper. Among other high-speed phenomena the gating circuitry capable of generating illumination periods shorter than 5ns can be used for Fluorescence Lifetime Imaging (FLIM). In order to measure the lifetime of fluorophores excited by a picosecond laser, the sensor's illumination period is synchronized with the excitation laser pulses. A histogram of the photon arrival times relative to the excitation is then constructed by counting the photons arriving during the sensitive time for several positions of the illumination window. The histogram for each pixel is transferred afterwards to a computer where software routines extract the lifetime at each location with an accuracy better than 100ps. We show results for fluorescence lifetime measurements using different fluorophores with lifetimes ranging from 150ps to 5ns.