Optimizing a synchrotron based x-ray lithography system for IC manufacturing

NASA Astrophysics Data System (ADS)

Kovacs, Stephen; Speiser, Kenneth; Thaw, Winston; Heese, Richard N.

1990-05-01

The electron storage ring is a realistic solution as a radiation source for production grade, industrial X-ray lithography system. Today several large scale plans are in motion to design and implement synchrotron storage rings of different types for this purpose in the USA and abroad. Most of the scientific and technological problems related to the physics, design and manufacturing engineering, and commissioning of these systems for microlithography have been resolved or are under extensive study. However, investigation on issues connected to application of Synchrotron Orbit Radiation (SOR ) in chip production environment has been somewhat neglected. In this paper we have filled this gap pointing out direct effects of some basic synchrotron design parameters and associated subsystems (injector, X-ray beam line) on the operation and cost of lithography in production. The following factors were considered: synchrotron configuration, injection energy, beam intensity variability, number of beam lines and wafer exposure concept. A cost model has been worked out and applied to three different X-ray Lithography Source (XLS) systems. The results of these applications are compared and conclusions drawn.

Fabrication of unique 3D microparticles in non-rectangular microchannels with flow lithography

NASA Astrophysics Data System (ADS)

Nam, Sung Min; Kim, Kibeom; Park, Wook; Lee, Wonhee

Invention of flow lithography has offered a simple yet effective method of fabricating micro-particles. However particles produced with conventional techniques were largely limited to 2-dimensional shapes projected to form a column. We proposed inexpensive and simple soft-lithography techniques to fabricate micro-channels with various cross-sectional shapes. The non-rectangular channels are then used to fabricate micro-particles using flow lithography resulting in interesting 3D shapes such as tetrahedrals or half-pyramids. In addition, a microfluidic device capable of fabricating multi-layered micro-particles was developed. On-chip PDMS valves are used to trap and position the particle at the precise location in microchannel with varying cross-section. Multilayer particles are generated by sequential monomer exchange and polymerization along the channel. While conventional multi-layered particles made with droplet generators require their layer materials be dissolved in immiscible fluids, the new method allows diverse choice of materials, not limited to their diffusibility. The multilayer 3D particles can be applied in areas such as drug delivery and tissue engineering.

Techniques for Type I Collagen Organization

NASA Astrophysics Data System (ADS)

Anderson-Jackson, LaTecia Diamond

Tissue Engineering is a process in which cells, engineering, and material methods are used in amalgamation to improve biological functions. The purpose of tissue engineering is to develop alternative solutions to treat or cure tissues and organs that have been severely altered or damaged by diseases, congenital defects, trauma, or cancer. One of the most common and most promising biological materials for tissue engineering to develop scaffolds is Type I collagen. A major challenge in biomedical research is aligning Type I collagen to mimic biological structures, such as ligaments, tendons, bones, and other hierarchal aligned structures within the human body. The intent of this research is to examine possible techniques for organizing Type I collagen and to assess which of the techniques is effective for potential biological applications. The techniques used in this research to organize collagen are soft lithography with solution-assisted sonication embossing, directional freezing, and direct poling. The final concentration used for both soft lithography with solution-assisted sonication embossing and direct poling was 1 mg/ml, whereas for directional freezing the final concentration varied between 4mg/ml, 2mg/ml, and 1 mg/ml. These techniques were characterized using the Atomic Force Microscope (AFM) and Helium Ion Microscope (HIM). In this study, we have found that out of the three techniques, the soft lithography and directional freezing techniques have been successful in organizing collagen in a particular pattern, but not alignment. We concluded alignment may be dependent on the pH of collagen and the amount of acetic acid used in collagen solution. However, experiments are still being conducted to optimize all three techniques to align collagen in a unidirectional arrangement.

Demonstration of lithography patterns using reflective e-beam direct write

NASA Astrophysics Data System (ADS)

Freed, Regina; Sun, Jeff; Brodie, Alan; Petric, Paul; McCord, Mark; Ronse, Kurt; Haspeslagh, Luc; Vereecke, Bart

2011-04-01

Traditionally, e-beam direct write lithography has been too slow for most lithography applications. E-beam direct write lithography has been used for mask writing rather than wafer processing since the maximum blur requirements limit column beam current - which drives e-beam throughput. To print small features and a fine pitch with an e-beam tool requires a sacrifice in processing time unless one significantly increases the total number of beams on a single writing tool. Because of the uncertainty with regards to the optical lithography roadmap beyond the 22 nm technology node, the semiconductor equipment industry is in the process of designing and testing e-beam lithography tools with the potential for high volume wafer processing. For this work, we report on the development and current status of a new maskless, direct write e-beam lithography tool which has the potential for high volume lithography at and below the 22 nm technology node. A Reflective Electron Beam Lithography (REBL) tool is being developed for high throughput electron beam direct write maskless lithography. The system is targeting critical patterning steps at the 22 nm node and beyond at a capital cost equivalent to conventional lithography. Reflective Electron Beam Lithography incorporates a number of novel technologies to generate and expose lithographic patterns with a throughput and footprint comparable to current 193 nm immersion lithography systems. A patented, reflective electron optic or Digital Pattern Generator (DPG) enables the unique approach. The Digital Pattern Generator is a CMOS ASIC chip with an array of small, independently controllable lens elements (lenslets), which act as an array of electron mirrors. In this way, the REBL system is capable of generating the pattern to be written using massively parallel exposure by ~1 million beams at extremely high data rates (~ 1Tbps). A rotary stage concept using a rotating platen carrying multiple wafers optimizes the writing strategy of the DPG to achieve the capability of high throughput for sparse pattern wafer levels. The lens elements on the DPG are fabricated at IMEC (Leuven, Belgium) under IMEC's CMORE program. The CMOS fabricated DPG contains ~ 1,000,000 lens elements, allowing for 1,000,000 individually controllable beamlets. A single lens element consists of 5 electrodes, each of which can be set at controlled voltage levels to either absorb or reflect the electron beam. A system using a linear movable stage and the DPG integrated into the electron optics module was used to expose patterns on device representative wafers. Results of these exposure tests are discussed.

Nanoengineered Plasmonic Hybrid Systems for Bio-nanotechnology

NASA Astrophysics Data System (ADS)

Leong, Kirsty

Plasmonic hybrid systems are fabricated using a combination of lithography and layer-by-layer directed self-assembly approaches to serve as highly sensitive nanosensing devices. This layer-by-layer directed self-assembly approach is utilized as a hybrid methodology to control the organization of quantum dots (QDs), nanoparticles, and biomolecules onto inorganic nanostructures with site-specific attachment and functionality. Here, surface plasmon-enhanced nanoarrays are fabricated where the photoluminescence of quantum dots and conjugated polymer nanoarrays are studied. This study was performed by tuning the localized surface plasmon resonance and the distance between the emitter and the metal surface using genetically engineered polypeptides as binding agents and biotin-streptavidin binding as linker molecules. In addition, these nanoarrays were also chemically modified to support the immobilization and label-free detection of DNA using surface enhanced Raman scattering. The surface of the nanoarrays was chemically modified using an acridine containing molecule which can act as an intercalating agent for DNA. The self-assembled monolayer (SAM) showed the ability to immobilize and intercalate DNA onto the surface. This SAM system using surface enhanced Raman scattering (SERS) serves as a highly sensitive methodology for the immobilization and label-free detection of DNA applicable into a wide range of bio-diagnostic platforms. Other micropatterned arrays were also fabricated using a combination of soft lithography and surface engineering. Selective single cell patterning and adhesion was achieved through chemical modifications and surface engineering of poly(dimethylsiloxane) surface. The surface of each microwell was functionally engineered with a SAM which contained an aldehyde terminated fused-ring aromatic thiolated molecule. Cells were found to be attracted and adherent to the chemically modified microwells. By combining soft lithography and surface engineering, a simple methodology produced single cell arrays on biocompatible substrates. Thus the design of plasmonic devices relies heavily on the nature of the plasmonic interactions between nanoparticles in the devices which can potentially be fabricated into lab-on-a-chip devices for multiplex sensing capabilities.

Variability-aware double-patterning layout optimization for analog circuits

NASA Astrophysics Data System (ADS)

Li, Yongfu; Perez, Valerio; Tripathi, Vikas; Lee, Zhao Chuan; Tseng, I.-Lun; Ong, Jonathan Yoong Seang

2018-03-01

The semiconductor industry has adopted multi-patterning techniques to manage the delay in the extreme ultraviolet lithography technology. During the design process of double-patterning lithography layout masks, two polygons are assigned to different masks if their spacing is less than the minimum printable spacing. With these additional design constraints, it is very difficult to find experienced layout-design engineers who have a good understanding of the circuit to manually optimize the mask layers in order to minimize color-induced circuit variations. In this work, we investigate the impact of double-patterning lithography on analog circuits and provide quantitative analysis for our designers to select the optimal mask to minimize the circuit's mismatch. To overcome the problem and improve the turn-around time, we proposed our smart "anchoring" placement technique to optimize mask decomposition for analog circuits. We have developed a software prototype that is capable of providing anchoring markers in the layout, allowing industry standard tools to perform automated color decomposition process.

High density arrays of micromirrors

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

Folta, J. M.; Decker, J. Y.; Kolman, J.

We established and achieved our goal to (1) fabricate and evaluate test structures based on the micromirror design optimized for maskless lithography applications, (2) perform system analysis and code development for the maskless lithography concept, and (3) identify specifications for micromirror arrays (MMAs) for LLNL's adaptive optics (AO) applications and conceptualize new devices.

3D nanofabrication inside rapid prototyped microfluidic channels showcased by wet-spinning of single micrometre fibres.

PubMed

Lölsberg, Jonas; Linkhorst, John; Cinar, Arne; Jans, Alexander; Kuehne, Alexander J C; Wessling, Matthias

2018-05-01

Microfluidics is an established multidisciplinary research domain with widespread applications in the fields of medicine, biotechnology and engineering. Conventional production methods of microfluidic chips have been limited to planar structures, preventing the exploitation of truly three-dimensional architectures for applications such as multi-phase droplet preparation or wet-phase fibre spinning. Here the challenge of nanofabrication inside a microfluidic chip is tackled for the showcase of a spider-inspired spinneret. Multiphoton lithography, an additive manufacturing method, was used to produce free-form microfluidic masters, subsequently replicated by soft lithography. Into the resulting microfluidic device, a three-dimensional spider-inspired spinneret was directly fabricated in-chip via multiphoton lithography. Applying this unprecedented fabrication strategy, the to date smallest printed spinneret nozzle is produced. This spinneret resides tightly sealed, connecting it to the macroscopic world. Its functionality is demonstrated by wet-spinning of single-digit micron fibres through a polyacrylonitrile coagulation process induced by a water sheath layer. The methodology developed here demonstrates fabrication strategies to interface complex architectures into classical microfluidic platforms. Using multiphoton lithography for in-chip fabrication adopts a high spatial resolution technology for improving geometry and thus flow control inside microfluidic chips. The showcased fabrication methodology is generic and will be applicable to multiple challenges in fluid control and beyond.

Lithography-based automation in the design of program defect masks

NASA Astrophysics Data System (ADS)

Vakanas, George P.; Munir, Saghir; Tejnil, Edita; Bald, Daniel J.; Nagpal, Rajesh

2004-05-01

In this work, we are reporting on a lithography-based methodology and automation in the design of Program Defect masks (PDM"s). Leading edge technology masks have ever-shrinking primary features and more pronounced model-based secondary features such as optical proximity corrections (OPC), sub-resolution assist features (SRAF"s) and phase-shifted mask (PSM) structures. In order to define defect disposition specifications for critical layers of a technology node, experience alone in deciding worst-case scenarios for the placement of program defects is necessary but may not be sufficient. MEEF calculations initiated from layout pattern data and their integration in a PDM layout flow provide a natural approach for improvements, relevance and accuracy in the placement of programmed defects. This methodology provides closed-loop feedback between layout and hard defect disposition specifications, thereby minimizing engineering test restarts, improving quality and reducing cost of high-end masks. Apart from SEMI and industry standards, best-known methods (BKM"s) in integrated lithographically-based layout methodologies and automation specific to PDM"s are scarce. The contribution of this paper lies in the implementation of Design-For-Test (DFT) principles to a synergistic interaction of CAD Layout and Aerial Image Simulator to drive layout improvements, highlight layout-to-fracture interactions and output accurate program defect placement coordinates to be used by tools in the mask shop.

Making structures for cell engineering.

PubMed

Wilkinson, C D W

2004-10-22

This is a mainly historical account of the events, methods and artifacts arising from my collaboration with Adam Curtis over the past twenty years to make exercise grounds for biological cells. Initially the structures were made in fused silica by photo-lithography and dry etching. The need to make micron-sized features in biodegradable polymers, led to the development of embossing techniques. Some cells response to grooves only a few tens of nanometers deep--this led to a desire to find the response of cells to features of nanometric size overall. Regular arrays of such features were made using electron beam lithography for definition of the pattern. Improvements were made in the lithographic techniques to allow arrays to be defined over areas bigger than 1 cm2. Structures with microelectrodes arranged inside guiding grooves to allow the formation of sparse predetermined networks of neurons were made. It is concluded that the creation of pattern, as in vivo, in assemblies of regrown cells in scaffolds may well be necessary in advanced cell engineering applications.

Controlling bridging and pinching with pixel-based mask for inverse lithography

NASA Astrophysics Data System (ADS)

Kobelkov, Sergey; Tritchkov, Alexander; Han, JiWan

2016-03-01

Inverse Lithography Technology (ILT) has become a viable computational lithography candidate in recent years as it can produce mask output that results in process latitude and CD control in the fab that is hard to match with conventional OPC/SRAF insertion approaches. An approach to solving the inverse lithography problem as a nonlinear, constrained minimization problem over a domain mask pixels was suggested in the paper by Y. Granik "Fast pixel-based mask optimization for inverse lithography" in 2006. The present paper extends this method to satisfy bridging and pinching constraints imposed on print contours. Namely, there are suggested objective functions expressing penalty for constraints violations, and their minimization with gradient descent methods is considered. This approach has been tested with an ILT-based Local Printability Enhancement (LPTM) tool in an automated flow to eliminate hotspots that can be present on the full chip after conventional SRAF placement/OPC and has been applied in 14nm, 10nm node production, single and multiple-patterning flows.

Merging Bottom-Up with Top-Down: Continuous Lamellar Networks and Block Copolymer Lithography

NASA Astrophysics Data System (ADS)

Campbell, Ian Patrick

Block copolymer lithography is an emerging nanopatterning technology with capabilities that may complement and eventually replace those provided by existing optical lithography techniques. This bottom-up process relies on the parallel self-assembly of macromolecules composed of covalently linked, chemically distinct blocks to generate periodic nanostructures. Among the myriad potential morphologies, lamellar structures formed by diblock copolymers with symmetric volume fractions have attracted the most interest as a patterning tool. When confined to thin films and directed to assemble with interfaces perpendicular to the substrate, two-dimensional domains are formed between the free surface and the substrate, and selective removal of a single block creates a nanostructured polymeric template. The substrate exposed between the polymeric features can subsequently be modified through standard top-down microfabrication processes to generate novel nanostructured materials. Despite tremendous progress in our understanding of block copolymer self-assembly, continuous two-dimensional materials have not yet been fabricated via this robust technique, which may enable nanostructured material combinations that cannot be fabricated through bottom-up methods. This thesis aims to study the effects of block copolymer composition and processing on the lamellar network morphology of polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) and utilize this knowledge to fabricate continuous two-dimensional materials through top-down methods. First, block copolymer composition was varied through homopolymer blending to explore the physical phenomena surrounding lamellar network continuity. After establishing a framework for tuning the continuity, the effects of various processing parameters were explored to engineer the network connectivity via defect annihilation processes. Precisely controlling the connectivity and continuity of lamellar networks through defect engineering and optimizing the block copolymer lithography process thus enabled the top-down fabrication of continuous two-dimensional gold networks with nanoscale properties. The lamellar structure of these networks was found to confer unique mechanical properties on the nanowire networks and suggests that materials templated via this method may be excellent candidates for integration into stretchable and flexible devices.

Micro-optics: enabling technology for illumination shaping in optical lithography

NASA Astrophysics Data System (ADS)

Voelkel, Reinhard

2014-03-01

Optical lithography has been the engine that has empowered semiconductor industry to continually reduce the half-pitch for over 50 years. In early mask aligners a simple movie lamp was enough to illuminate the photomask. Illumination started to play a more decisive role when proximity mask aligners appeared in the mid-1970s. Off-axis illumination was introduced to reduce diffraction effects. For early projection lithography systems (wafer steppers), the only challenge was to collect the light efficiently to ensure short exposure time. When projection optics reached highest level of perfection, further improvement was achieved by optimizing illumination. Shaping the illumination light, also referred as pupil shaping, allows the optical path from reticle to wafer to be optimized and thus has a major impact on aberrations and diffraction effects. Highly-efficient micro-optical components are perfectly suited for this task. Micro-optics for illumination evolved from simple flat-top (fly's-eye) to annular, dipole, quadrupole, multipole and freeform illumination. Today, programmable micro-mirror arrays allow illumination to be changed on the fly. The impact of refractive, diffractive and reflective microoptics for photolithography will be discussed.

Scanning two-photon continuous flow lithography for synthesis of high-resolution 3D microparticles.

PubMed

Shaw, Lucas A; Chizari, Samira; Shusteff, Maxim; Naghsh-Nilchi, Hamed; Di Carlo, Dino; Hopkins, Jonathan B

2018-05-14

Demand continues to rise for custom-fabricated and engineered colloidal microparticles across a breadth of application areas. This paper demonstrates an improvement in the fabrication rate of high-resolution 3D colloidal particles by using two-photon scanning lithography within a microfluidic channel. To accomplish this, we present (1) an experimental setup that supports fast, 3D scanning by synchronizing a galvanometer, piezoelectric stage, and an acousto-optic switch, and (2) a new technique for modifying the laser's scan path to compensate for the relative motion of the rapidly-flowing photopolymer medium. The result is an instrument that allows for rapid conveyor-belt-like fabrication of colloidal objects with arbitrary 3D shapes and micron-resolution features.

Examination for optimization of synchrotron radiation spectrum for the x ray depth lithography

NASA Astrophysics Data System (ADS)

Dany, Raimund

1992-06-01

The effect of reducing the vertical distribution of synchrotron radiation on its spectral distribution is examined through resin irradiation. The resulting filter effect is compared to that of absorption filters. Transmission coefficients of titanium, gold, and polyamide were calculated from linear absorption coefficients with the Beer law. The use of a diaphragm in X-ray depth lithography, which is the first step of the LIGA (Lithography Galvanoforming Molding) process, is discussed. A calorimetric device for determining the synchrotron radiation power and distribution was developed and tested. Measurements at the ELSA storage ring show a strong dependence of the vertical emittance on the electron current.

Mastering multi-depth bio-chip patterns with DVD LBRs

NASA Astrophysics Data System (ADS)

Carson, Doug

2017-08-01

Bio chip and bio disc are rapidly growing technologies used in medical, health and other industries. While there are numerous unique designs and features, these products all rely on precise three-dimensional micro-fluidic channels or arrays to move, separate and combine samples under test. These bio chip and bio disc consumables are typically manufactured by molding these parts to a precise three-dimensional pattern on a negative metal stamper, or they can be made in smaller quantities using an appropriate curable resin and a negative mold/stamper. Stampers required for bio chips have been traditionally made using either micro machining or XY stepping lithography. Both of these technologies have their advantages as well as limitations when it comes to creating micro-fluidic patterns. Significant breakthroughs in continuous maskless lithography have enabled accurate and efficient manufacturing of micro-fluidic masters using LBRs (Laser Beam Recorders) and DRIE (Deep Reactive Ion Etching). The important advantages of LBR continuous lithography vs. XY stepping lithography and micro machining are speed and cost. LBR based continuous lithography is >100x faster than XY stepping lithography and more accurate than micro machining. Several innovations were required in order to create multi-depth patterns with sub micron accuracy. By combining proven industrial LBRs with DCA's G3-VIA pattern generator and DRIE, three-dimensional bio chip masters and stampers are being manufactured efficiently and accurately.

Carbon dioxide gas purification and analytical measurement for leading edge 193nm lithography

NASA Astrophysics Data System (ADS)

Riddle Vogt, Sarah; Landoni, Cristian; Applegarth, Chuck; Browning, Matt; Succi, Marco; Pirola, Simona; Macchi, Giorgio

2015-03-01

The use of purified carbon dioxide (CO2) has become a reality for leading edge 193 nm immersion lithography scanners. Traditionally, both dry and immersion 193 nm lithographic processes have constantly purged the optics stack with ultrahigh purity compressed dry air (UHPCDA). CO2 has been utilized for a similar purpose as UHPCDA. Airborne molecular contamniation (AMC) purification technologies and analytical measurement methods have been extensively developed to support the Lithography Tool Manufacturers purity requirements. This paper covers the analytical tests and characterizations carried out to assess impurity removal from 3.0 N CO2 (beverage grade) for its final utilization in 193 nm and EUV scanners.

Patterning and templating for nanoelectronics.

PubMed

Galatsis, Kosmas; Wang, Kang L; Ozkan, Mihri; Ozkan, Cengiz S; Huang, Yu; Chang, Jane P; Monbouquette, Harold G; Chen, Yong; Nealey, Paul; Botros, Youssry

2010-02-09

The semiconductor industry will soon be launching 32 nm complementary metal oxide semiconductor (CMOS) technology node using 193 nm lithography patterning technology to fabricate microprocessors with more than 2 billion transistors. To ensure the survival of Moore's law, alternative patterning techniques that offer advantages beyond conventional top-down patterning are aggressively being explored. It is evident that most alternative patterning techniques may not offer compelling advantages to succeed conventional top-down lithography for silicon integrated circuits, but alternative approaches may well indeed offer functional advantages in realising next-generation information processing nanoarchitectures such as those based on cellular, bioinsipired, magnetic dot logic, and crossbar schemes. This paper highlights and evaluates some patterning methods from the Center on Functional Engineered Nano Architectonics in Los Angeles and discusses key benchmarking criteria with respect to CMOS scaling.

Optimized filtration for reduced defectivity and improved dispense recipe in 193-nm BARC lithography

NASA Astrophysics Data System (ADS)

Do, Phong; Pender, Joe; Lehmann, Thomas; Mc Ardle, Leo P.; Gotlinsky, Barry; Mesawich, Michael

2004-05-01

The implementation of 193 nm lithography into production has been complicated by high defectivity issues. Many companies have been struggling with high defect densities, forcing process and lithography engineers to focus their efforts on chemical filtration instead of process development. After-etch defects have complicated the effort to reduce this problem. In particular it has been determined that chemical filtration at the 90 nm node and below is a crucial item which current industry standard pump recipes and material choices are not able to address. LSI Logic and Pall Corporation have been working together exploring alternative materials and resist pump process parameters to address these issues. These changes will free up process development time by reducing these high defect density issues. This paper provides a fundamental understanding of how 20nm filtration combined with optimized resist pump set-up and dispense can significantly reduce defects in 193nm lithography. The purpose of this study is to examine the effectiveness of 20 nanometer rated filters to reduce various defects observed in bottom anti reflective coating materials. Multiple filter types were installed on a Tokyo Electron Limited Clean Track ACT8 tool utilizing two-stage resist pumps. Lithographic performance of the filtered resist and defect analysis of patterned and non-patterned wafers were performed. Optimized pump start-up and dispense recipes also were evaluated to determine their effect on defect improvements. The track system used in this experiment was a standard production tool and was not modified from its original specifications.

Facilitating Integration of Electron Beam Lithography Devices with Interactive Videodisc, Computer-Based Simulation and Job Aids.

ERIC Educational Resources Information Center

Von Der Linn, Robert Christopher

A needs assessment of the Grumman E-Beam Systems Group identified the requirement for additional skill mastery for the engineers who assemble, integrate, and maintain devices used to manufacture integrated circuits. Further analysis of the tasks involved led to the decision to develop interactive videodisc, computer-based job aids to enable…

Marching of the microlithography horses: electron, ion, and photon: past, present, and future

NASA Astrophysics Data System (ADS)

Lin, Burn J.

2007-03-01

Microlithography patterning employs one of three media; electron, ion, and photon. They are in a way like horses, racing towards the mainstream. Some horses such as electrons run fast but repel each other. Ion beams behave like electron beams but are less developed. The photon beam is the undisputed workhorse, taking microlithography from the 5-μm minimum feature size to 32-nm half pitch. This paper examines the history of microlithography in pattern generation, proximity printing, and projection printing, then identifies the strong and weak points of each technology. In addition to ion-beam and e-beam lithography, the coverage of optical lithography spans the wavelength from 436 to 13.5 nm. Our learning from history helps us prevent mistakes in the future. In almost all cases, making or using the mask presents one of the limiting problems, no matter the type of beams or the replication method. Only the maskless method relieves us from mask-related problems. A way to overcome the low throughput handicap of maskless systems is to use multiple e-beam direct writing, whose imaging lens can be economically and compactly fabricated using MEMS techniques. In a way, the history of microlithography parallels that of aviation. Proximity printing is like the Wright-Brothers' plane; 1X projection printing, single-engine propeller plane with unitized body; reduction step-and-repeat projection printing, multi-engine commercial airliner; scanners, jet airliners. Optical lithography has improved in many ways than just increasing NA and reducing wavelength just as the commercial airliners improving in many other areas than just the speed. The SST increased the speed of airliners by more than a factor of two just as optical resolution doubled with double exposures. EUV lithography with the wavelength reduced by an order of magnitude is similar to the space shuttle increasing its speed to more than 10 times that of the SST. Multiple-beam direct write systems are like helicopters. They do not need airports(masks) but we need a lot of beams to carry the same payload.

Microfabrication of Cell-Laden Hydrogels for Engineering Mineralized and Load Bearing Tissues.

PubMed

Li, Chia-Cheng; Kharaziha, Mahshid; Min, Christine; Maas, Richard; Nikkhah, Mehdi

2015-01-01

Microengineering technologies and advanced biomaterials have extensive applications in the field of regenerative medicine. In this chapter, we review the integration of microfabrication techniques and hydrogel-based biomaterials in the field of dental, bone, and cartilage tissue engineering. We primarily discuss the major features that make hydrogels attractive candidates to mimic extracellular matrix (ECM), and we consider the benefits of three-dimensional (3D) culture systems for tissue engineering applications. We then focus on the fundamental principles of microfabrication techniques including photolithography, soft lithography and bioprinting approaches. Lastly, we summarize recent research on microengineering cell-laden hydrogel constructs for dental, bone and cartilage regeneration, and discuss future applications of microfabrication techniques for load-bearing tissue engineering.

Design, Fabrication and Characterization of Micro Opto-Electro-Mechanical Systems.

DTIC Science & Technology

1995-12-01

interference problems (see Fig. 3-6). Improvements in the lithography of the MCNC process would allow for grating spaces of less than 2 gm and therefore...A micro-spectrometer has been fabricated using LIGA, an acronym for lithography , electroforming, and micromolding (the acronym came from the German...location for test samples and an adjustable mirror. The beams are brought back together to form an interference pattern. At an observation screen the

Extending the performance of KrF laser for microlithography by using novel F2 control technology

NASA Astrophysics Data System (ADS)

Zambon, Paolo; Gong, Mengxiong; Carlesi, Jason; Padmabandu, Gunasiri G.; Binder, Mike; Swanson, Ken; Das, Palash P.

2000-07-01

Exposure tools for 248nm lithography have reached a level of maturity comparable to those based on i-line. With this increase in maturity, there is a concomitant requirement for greater flexibility from the laser by the process engineers. Usually, these requirements pertain to energy, spectral width and repetition rate. By utilizing a combination of laser parameters, the process engineers are often able to optimize throughput, reduce cost-of-operation or achieve greater process margin. Hitherto, such flexibility of laser operation was possible only via significant changes to various laser modules. During our investigation, we found that the key measure of the laser that impacts the aforementioned parameters is its F2 concentration. By monitoring and controlling its slope efficiency, the laser's F2 concentration may be precisely controlled. Thus a laser may tune to operate under specifications as diverse as 7mJ, (Delta) (lambda) FWHM < 0.3 pm and 10mJ, (Delta) (lambda) FWHM < 0.6pm and still meet the host of requirements necessary for lithography. We discus this new F2 control technique and highlight some laser performance parameters.

Advanced electric-field scanning probe lithography on molecular resist using active cantilever

NASA Astrophysics Data System (ADS)

Kaestner, Marcus; Aydogan, Cemal; Ivanov, Tzvetan; Ahmad, Ahmad; Angelov, Tihomir; Reum, Alexander; Ishchuk, Valentyn; Krivoshapkina, Yana; Hofer, Manuel; Lenk, Steve; Atanasov, Ivaylo; Holz, Mathias; Rangelow, Ivo W.

2015-07-01

The routine "on demand" fabrication of features smaller than 10 nm opens up new possibilities for the realization of many devices. Driven by the thermally actuated piezoresistive cantilever technology, we have developed a prototype of a scanning probe lithography (SPL) platform which is able to image, inspect, align, and pattern features down to the single digit nanoregime. Here, we present examples of practical applications of the previously published electric-field based current-controlled scanning probe lithography. In particular, individual patterning tests are carried out on calixarene by using our developed table-top SPL system. We have demonstrated the application of a step-and-repeat SPL method including optical as well as atomic force microscopy-based navigation and alignment. The closed-loop lithography scheme was applied to sequentially write positive and negative tone features. Due to the integrated unique combination of read-write cycling, each single feature is aligned separately with the highest precision and inspected after patterning. This routine was applied to create a pattern step by step. Finally, we have demonstrated the patterning over larger areas, over existing topography, and the practical applicability of the SPL processes for lithography down to 13-nm pitch patterns. To enhance the throughput capability variable beam diameter electric field, current-controlled SPL is briefly discussed.

Non-CAR resists and advanced materials for Massively Parallel E-Beam Direct Write process integration

NASA Astrophysics Data System (ADS)

Pourteau, Marie-Line; Servin, Isabelle; Lepinay, Kévin; Essomba, Cyrille; Dal'Zotto, Bernard; Pradelles, Jonathan; Lattard, Ludovic; Brandt, Pieter; Wieland, Marco

2016-03-01

The emerging Massively Parallel-Electron Beam Direct Write (MP-EBDW) is an attractive high resolution high throughput lithography technology. As previously shown, Chemically Amplified Resists (CARs) meet process/integration specifications in terms of dose-to-size, resolution, contrast, and energy latitude. However, they are still limited by their line width roughness. To overcome this issue, we tested an alternative advanced non-CAR and showed it brings a substantial gain in sensitivity compared to CAR. We also implemented and assessed in-line post-lithographic treatments for roughness mitigation. For outgassing-reduction purpose, a top-coat layer is added to the total process stack. A new generation top-coat was tested and showed improved printing performances compared to the previous product, especially avoiding dark erosion: SEM cross-section showed a straight pattern profile. A spin-coatable charge dissipation layer based on conductive polyaniline has also been tested for conductivity and lithographic performances, and compatibility experiments revealed that the underlying resist type has to be carefully chosen when using this product. Finally, the Process Of Reference (POR) trilayer stack defined for 5 kV multi-e-beam lithography was successfully etched with well opened and straight patterns, and no lithography-etch bias.

Feasibility of Air Levitated Surface Stage for Lithography Tool

NASA Astrophysics Data System (ADS)

Tanaka, Keiichi

The application of light-weight drive technology into the lithography stage has been the current state of art because of minimization of power loss. The purpose of this article is to point out the so-called, "surface stage" which is composed of Lorentz forced 3 DOF (Degree Of Freedom) planar motor (x, y and theta z), air levitation (bearing) system and motor cooling system, is the most balanced concept for the next generation lithography through the verification of each component by manufacturing simple parts and test stand. This paper presents the design method and procedure, and experimental results of the air levitated surface stage which was conducted several years ago, however the author is convinced that the results are enough to adapt various developments of precision machining tool.

Protein assay structured on paper by using lithography

NASA Astrophysics Data System (ADS)

Wilhelm, E.; Nargang, T. M.; Al Bitar, W.; Waterkotte, B.; Rapp, B. E.

2015-03-01

There are two main challenges in producing a robust, paper-based analytical device. The first one is to create a hydrophobic barrier which unlike the commonly used wax barriers does not break if the paper is bent. The second one is the creation of the (bio-)specific sensing layer. For this proteins have to be immobilized without diminishing their activity. We solve both problems using light-based fabrication methods that enable fast, efficient manufacturing of paper-based analytical devices. The first technique relies on silanization by which we create a flexible hydrophobic barrier made of dimethoxydimethylsilane. The second technique demonstrated within this paper uses photobleaching to immobilize proteins by means of maskless projection lithography. Both techniques have been tested on a classical lithography setup using printed toner masks and on a lithography system for maskless lithography. Using these setups we could demonstrate that the proposed manufacturing techniques can be carried out at low costs. The resolution of the paper-based analytical devices obtained with static masks was lower due to the lower mask resolution. Better results were obtained using advanced lithography equipment. By doing so we demonstrated, that our technique enables fabrication of effective hydrophobic boundary layers with a thickness of only 342 μm. Furthermore we showed that flourescine-5-biotin can be immobilized on the non-structured paper and be employed for the detection of streptavidinalkaline phosphatase. By carrying out this assay on a paper-based analytical device which had been structured using the silanization technique we proofed biological compatibility of the suggested patterning technique.

Patterned self-assembled monolayers for nanoscale lithography and the control of catalytically produced electroosmosis

NASA Astrophysics Data System (ADS)

Subramanian, Shyamala

This thesis explores two applications of self-assembled monolayers (SAMs) (a) for developing novel molecular assembly based nanolithography techniques and (b) for tailoring zeta-potential of surfaces towards achieving directional control of catalytically induced fluid flow. The first half of the thesis develops the process of molecular ruler lithography using sacrificial host structures. This is a novel hybrid nanolithography technique which combines chemical self-assembly with conventional fabrication methods for improving the resolution of existing lithography tools to sub-50 nm. Previous work related to molecular ruler lithography have shown the use of thiol-SAMs, placed one on top of the other like a molecular resist, for scaling down feature sizes. In this thesis various engineering solutions for improving the reproducibility, yield, nanoscale roughness and overall manufacturability of the process are introduced. This is achieved by introducing a sacrificial inert layer underneath the gold parent structure. This bilayer sacrificial host allows for preferential, easy and quick removal of the parent structures, isolates the parent metal from the underlying substrate and improves reproducibility of the lift-off process. Also it opens avenues for fabrication of high aspect ratio features. Also molecular layer vapor deposition method is developed for building the multilayer molecular resist via vapor phase to reduce contaminations and yield issues associated with solution phase deposition. The smallest isolated metal features produced using this process were 40 nm in width. The second half of the thesis describes application of thiol-SAMs to tailor surface properties of gold, specifically the surface charge or zeta potential. Previous work has demonstrated that the direction of movement of fluid in the vicinity of a catalytically active bimetallic junction placed in a solution of dilute hydrogen peroxide depends on the charge of the gold surface. SAMs with different end-group functionality impart different surface zeta potential to the gold surface. Zeta-potential engineering via patterning various end-group functionalized SAMs on gold surface to control direction of catalytically induced electroosmotic fluid flow is demonstrated for the first time. This work also describes the application of catalytic power to produce controlled rotational motion. Gold gears-like structures made using conventional microfabrication techniques and propelled by catalytic power are shown to rotate at speeds of 1 rotation/sec in a dilute solution of hydrogen peroxide. Fabrication of a force sensor for detection and measurement of catalytic forces is also introduced. The force sensor, with sensitivity in the piconewton range, consists of a microcantilever with a catalytically active silver post patterned on the tip. Changes in cantilever displacement and resonance frequency due to the catalytic force were monitored as a function of concentration of hydrogen peroxide. Overall, this thesis integrates SAM deposition and patterning techniques with conventional fabrication methods to engineer and control nanoscale structures and devices. Possible future device designs are described including CMOS devices having channel width defined using molecular ruler lithography with sacrificial hosts, drug delivery device based on AFM force sensor and channeless pumps powered by catalytic reactions with SAM controlled electroosmotic fluid flow.

Lithography alternatives meet design style reality: How do they "line" up?

NASA Astrophysics Data System (ADS)

Smayling, Michael C.

2016-03-01

Optical lithography resolution scaling has stalled, giving innovative alternatives a window of opportunity. One important factor that impacts these lithographic approaches is the transition in design style from 2D to 1D for advanced CMOS logic. Just as the transition from 3D circuits to 2D fabrication 50 years ago created an opportunity for a new breed of electronics companies, the transition today presents exciting and challenging time for lithographers. Today, we are looking at a range of non-optical lithography processes. Those considered here can be broadly categorized: self-aligned lithography, self-assembled lithography, deposition lithography, nano-imprint lithography, pixelated e-beam lithography, shot-based e-beam lithography .Do any of these alternatives benefit from or take advantage of 1D layout? Yes, for example SAPD + CL (Self Aligned Pitch Division combined with Complementary Lithography). This is a widely adopted process for CMOS nodes at 22nm and below. Can there be additional design / process co-optimization? In spite of the simple-looking nature of 1D layout, the placement of "cut" in the lines and "holes" for interlayer connections can be tuned for a given process capability. Examples of such optimization have been presented at this conference, typically showing a reduction of at least one in the number of cut or hole patterns needed.[1,2] Can any of the alternatives complement each other or optical lithography? Yes.[3] For example, DSA (Directed Self Assembly) combines optical lithography with self-assembly. CEBL (Complementary e-Beam Lithography) combines optical lithography with SAPD for lines with shot-based e-beam lithography for cuts and holes. Does one (shrinking) size fit all? No, that's why we have many alternatives. For example NIL (Nano-imprint Lithography) has been introduced for NAND Flash patterning where the (trending lower) defectivity is acceptable for the product. Deposition lithography has been introduced in 3D NAND Flash to set the channel length of select and memory transistors.

Engineered arrays of nitrogen-vacancy color centers in diamond based on implantation of CN- molecules through nanoapertures

NASA Astrophysics Data System (ADS)

Spinicelli, P.; Dréau, A.; Rondin, L.; Silva, F.; Achard, J.; Xavier, S.; Bansropun, S.; Debuisschert, T.; Pezzagna, S.; Meijer, J.; Jacques, V.; Roch, J.-F.

2011-02-01

We report a versatile method for engineering arrays of nitrogen-vacancy (NV) color centers in diamond at the nanoscale. The defects were produced in parallel by ion implantation through 80 nm diameter apertures patterned using electron beam lithography in a polymethyl methacrylate (PMMA) layer deposited on a diamond surface. The implantation was performed with CN- molecules that increased the NV defect-formation yield. This method could enable the realization of a solid-state coupled-spin array and could be used for positioning an optically active NV center on a photonic microstructure.

Tunable Infrared Metasurface on a Soft Polymer Scaffold.

PubMed

Reeves, Jeremy B; Jayne, Rachael K; Stark, Thomas J; Barrett, Lawrence K; White, Alice E; Bishop, David J

2018-05-09

The fabrication of metallic electromagnetic meta-atoms on a soft microstructured polymer scaffold using a MEMS-based stencil lithography technique is demonstrated. Using this technique, complex metasurfaces that are generally impossible to fabricate with traditional photolithographic techniques are created. By engineering the mechanical deformation of the polymer scaffold, the metasurface reflectivity in the mid-infrared can be tuned by the application of moderate strains.

Lithographic microfabrication of biocompatible polymers for tissue engineering and lab-on-a-chip applications

NASA Astrophysics Data System (ADS)

Balciunas, Evaldas; Jonusauskas, Linas; Valuckas, Vytautas; Baltriukiene, Daiva; Bukelskiene, Virginija; Gadonas, Roaldas; Malinauskas, Mangirdas

2012-06-01

In this work, a combination of Direct Laser Writing (DLW), PoliDiMethylSiloxane (PDMS) soft lithography and UV lithography was used to create cm- scale microstructured polymer scaolds for cell culture experiments out of dierent biocompatible materials: novel hybrid organic-inorganic SZ2080, PDMS elastomer, biodegradable PEG- DA-258 and SU-8. Rabbit muscle-derived stem cells were seeded on the fabricated dierent periodicity scaolds to evaluate if the relief surface had any eect on cell proliferation. An array of microlenses was fabricated using DLW out of SZ2080 and replicated in PDMS and PEG-DA-258, showing good potential applicability of the used techniques in many other elds like micro- and nano- uidics, photonics, and MicroElectroMechanical Systems (MEMS). The synergetic employment of three dierent fabrication techniques allowed to produce desired objects with low cost, high throughput and precision as well as use materials that are dicult to process by other means (PDMS and PEG-DA-258). DLW is a relatively slow fabrication method, since the object has to be written point-by-point. By applying PDMS soft lithography, we were enabled to replicate laser-fabricated scaolds for stem cell growth and micro-optical elements for lab-on-a-chip applications with high speed, low cost and good reproducible quality.

Plasmonic colour generation

NASA Astrophysics Data System (ADS)

Kristensen, Anders; Yang, Joel K. W.; Bozhevolnyi, Sergey I.; Link, Stephan; Nordlander, Peter; Halas, Naomi J.; Mortensen, N. Asger

2017-01-01

Plasmonic colours are structural colours that emerge from resonant interactions between light and metallic nanostructures. The engineering of plasmonic colours is a promising, rapidly emerging research field that could have a large technological impact. We highlight basic properties of plasmonic colours and recent nanofabrication developments, comparing technology-performance indicators for traditional and nanophotonic colour technologies. The structures of interest include diffraction gratings, nanoaperture arrays, thin films, and multilayers and structures that support Mie resonances and whispering-gallery modes. We discuss plasmonic colour nanotechnology based on localized surface plasmon resonances, such as gap plasmons and hybridized disk-hole plasmons, which allow for colour printing with sub-diffraction resolution. We also address a range of fabrication approaches that enable large-area printing and nanoscale lithography compatible with complementary metal-oxide semiconductor technologies, including nanoimprint lithography and self-assembly. Finally, we review recent developments in dynamically reconfigurable plasmonic colours and in the laser-induced post-processing of plasmonic colour surfaces.

Trehalose glycopolymer resists allow direct writing of protein patterns by electron-beam lithography

NASA Astrophysics Data System (ADS)

Bat, Erhan; Lee, Juneyoung; Lau, Uland Y.; Maynard, Heather D.

2015-03-01

Direct-write patterning of multiple proteins on surfaces is of tremendous interest for a myriad of applications. Precise arrangement of different proteins at increasingly smaller dimensions is a fundamental challenge to apply the materials in tissue engineering, diagnostics, proteomics and biosensors. Herein, we present a new resist that protects proteins during electron-beam exposure and its application in direct-write patterning of multiple proteins. Polymers with pendant trehalose units are shown to effectively crosslink to surfaces as negative resists, while at the same time providing stabilization to proteins during the vacuum and electron-beam irradiation steps. In this manner, arbitrary patterns of several different classes of proteins such as enzymes, growth factors and immunoglobulins are realized. Utilizing the high-precision alignment capability of electron-beam lithography, surfaces with complex patterns of multiple proteins are successfully generated at the micrometre and nanometre scale without requiring cleanroom conditions.

Interpreting cost of ownership for mix-and-match lithography

NASA Astrophysics Data System (ADS)

Levine, Alan L.; Bergendahl, Albert S.

1994-05-01

Cost of ownership modeling is a critical and emerging tool that provides significant insight into the ways to optimize device manufacturing costs. The development of a model to deal with a particular application, mix-and-match lithography, was performed in order to determine the level of cost savings and the optimum ways to create these savings. The use of sensitivity analysis with cost of ownership allows the user to make accurate trade-offs between technology and cost. The use and interpretation of the model results are described in this paper. Parameters analyzed include several manufacturing considerations -- depreciation, maintenance, engineering and operator labor, floorspace, resist, consumables and reticles. Inherent in this study is the ability to customize this analysis for a particular operating environment. Results demonstrate the clear advantages of a mix-and-match approach for three different operating environments. These case studies also demonstrate various methods to efficiently optimize cost savings strategies.

Tunable laser interference lithography preparation of plasmonic nanoparticle arrays tailored for SERS.

PubMed

Gisbert Quilis, Nestor; Lequeux, Médéric; Venugopalan, Priyamvada; Khan, Imran; Knoll, Wolfgang; Boujday, Souhir; Lamy de la Chapelle, Marc; Dostalek, Jakub

2018-05-23

The facile preparation of arrays of plasmonic nanoparticles over a square centimeter surface area is reported. The developed method relies on tailored laser interference lithography (LIL) that is combined with dry etching and it offers means for the rapid fabrication of periodic arrays of metallic nanostructures with well controlled morphology. Adjusting the parameters of the LIL process allows for the preparation of arrays of nanoparticles with a diameter below hundred nanometers independently of their lattice spacing. Gold nanoparticle arrays were precisely engineered to support localized surface plasmon resonance (LSPR) with different damping at desired wavelengths in the visible and near infrared part of the spectrum. The applicability of these substrates for surface enhanced Raman scattering is demonstrated where cost-effective, uniform and reproducible substrates are of paramount importance. The role of deviations in the spectral position and the width of the LSPR band affected by slight variations of plasmonic nanostructures is discussed.

The application of phase grating to CLM technology for the sub-65nm node optical lithography

NASA Astrophysics Data System (ADS)

Yoon, Gi-Sung; Kim, Sung-Hyuck; Park, Ji-Soong; Choi, Sun-Young; Jeon, Chan-Uk; Shin, In-Kyun; Choi, Sung-Woon; Han, Woo-Sung

2005-06-01

As a promising technology for sub-65nm node optical lithography, CLM(Chrome-Less Mask) technology among RETs(Resolution Enhancement Techniques) for low k1 has been researched worldwide in recent years. CLM has several advantages, such as relatively simple manufacturing process and competitive performance compared to phase-edge PSM's. For the low-k1 lithography, we have researched CLM technique as a good solution especially for sub-65nm node. As a step for developing the sub-65nm node optical lithography, we have applied CLM technology in 80nm-node lithography with mesa and trench method. From the analysis of the CLM technology in the 80nm lithography, we found that there is the optimal shutter size for best performance in the technique, the increment of wafer ADI CD varied with pattern's pitch, and a limitation in patterning various shapes and size by OPC dead-zone - OPC dead-zone in CLM technique is the specific region of shutter size that dose not make the wafer CD increased more than a specific size. And also small patterns are easily broken, while fabricating the CLM mask in mesa method. Generally, trench method has better optical performance than mesa. These issues have so far restricted the application of CLM technology to a small field. We approached these issues with 3-D topographic simulation tool and found that the issues could be overcome by applying phase grating in trench-type CLM. With the simulation data, we made some test masks which had many kinds of patterns with many different conditions and analyzed their performance through AIMS fab 193 and exposure on wafer. Finally, we have developed the CLM technology which is free of OPC dead-zone and pattern broken in fabrication process. Therefore, we can apply the CLM technique into sub-65nm node optical lithography including logic devices.

Fabrication of micro/nano hierarchical structures with analysis on the surface mechanics

NASA Astrophysics Data System (ADS)

Jheng, Yu-Sheng; Lee, Yeeu-Chang

2016-10-01

Biomimicry refers to the imitation of mechanisms and features found in living creatures using artificial methods. This study used optical lithography, colloidal lithography, and dry etching to mimic the micro/nano hierarchical structures covering the soles of gecko feet. We measured the static contact angle and contact angle hysteresis to reveal the behavior of liquid drops on the hierarchical structures. Pulling tests were also performed to measure the resistance of movement between the hierarchical structures and a testing plate. Our results reveal that hierarchical structures at the micro-/nano-scale are considerably hydrophobic, they provide good flow characteristics, and they generate more contact force than do surfaces with micro-scale cylindrical structures.

Simulation study of reticle enhancement technology applications for 157-nm lithography

NASA Astrophysics Data System (ADS)

Schurz, Dan L.; Flack, Warren W.; Karklin, Linard

2002-03-01

The acceleration of the International Technology Roadmap for Semiconductors (ITRS) is placing significant pressure on the industry's infrastructure, particularly the lithography equipment. As recently as 1997, there was no optical solution offered past the 130 nm design node. The current roadmap has the 65 nm node (reduced from 70 nm) pulled in one year to 2007. Both 248 nm and 193 nm wavelength lithography tools will be pushed to their practical resolution limits in the near term. Very high numerical aperture (NA) 193 nm exposure tools in conjunction with resolution enhancement techniques (RET) will postpone the requirement for 157 nm lithography in manufacturing. However, ICs produced at 70 nm design rules with manufacturable k 1 values will require that 157 nm wavelength lithography tools incorporate the same RETs utilized in 248nm, and 193 nm tools. These enhancements will include Alternating Phase Shifting Masks (AltPSM) and Optical Proximity Correction (OPC) on F 2 doped quartz reticle substrates. This study investigates simulation results when AltPSM is applied to sub-100 nm test patterns in 157 nm lithography in order to maintain Critical Dimension (CD) control for both nested and isolated geometries. Aerial image simulations are performed for a range of numerical apertures, chrome regulators, gate pitches and gate widths. The relative performance for phase shifted versus binary structures is also compared. Results are demonstrated in terms of aerial image contrast and process window changes. The results clearly show that a combination of high NA and RET is necessary to achieve usable process windows for 70 nm line/space structures. In addition, it is important to consider two-dimensional proximity effects for sub-100 nm gate structures.

Inspection of imprint lithography patterns for semiconductor and patterned media

NASA Astrophysics Data System (ADS)

Resnick, Douglas J.; Haase, Gaddi; Singh, Lovejeet; Curran, David; Schmid, Gerard M.; Luo, Kang; Brooks, Cindy; Selinidis, Kosta; Fretwell, John; Sreenivasan, S. V.

2010-03-01

Imprint lithography has been shown to be an effective technique for replication of nano-scale features. Acceptance of imprint lithography for manufacturing will require demonstration that it can attain defect levels commensurate with the requirements of cost-effective device production. This work summarizes the results of defect inspections of semiconductor masks, wafers and hard disks patterned using Jet and Flash Imprint Lithography (J-FILTM). Inspections were performed with optical and e-beam based automated inspection tools. For the semiconductor market, a test mask was designed which included dense features (with half pitches ranging between 32 nm and 48 nm) containing an extensive array of programmed defects. For this work, both e-beam inspection and optical inspection were used to detect both random defects and the programmed defects. Analytical SEMs were then used to review the defects detected by the inspection. Defect trends over the course of many wafers were observed with another test mask using a KLA-T 2132 optical inspection tool. The primary source of defects over 2000 imprints were particle related. For the hard drive market, it is important to understand the defectivity of both the template and the imprinted disk. This work presents a methodology for automated pattern inspection and defect classification for imprint-patterned media. Candela CS20 and 6120 tools from KLA-Tencor map the optical properties of the disk surface, producing highresolution grayscale images of surface reflectivity, scattered light, phase shift, etc. Defects that have been identified in this manner are further characterized according to the morphology

Impact of materials engineering on edge placement error (Conference Presentation)

NASA Astrophysics Data System (ADS)

Freed, Regina; Mitra, Uday; Zhang, Ying

2017-04-01

Transistor scaling has transitioned from wavelength scaling to multi-patterning techniques, due to the resolution limits of immersion of immersion lithography. Deposition and etch have enabled scaling in the by means of SADP and SAQP. Spacer based patterning enables extremely small linewidths, sufficient for several future generations of transistors. However, aligning layers in Z-direction, as well as aligning cut and via patterning layers, is becoming a road-block due to global and local feature variation and fidelity. This presentation will highlight the impact of deposition and etch on this feature alignment (EPE) and illustrate potential paths toward lowering EPE using material engineering.

Maskless Lithography Using Negative Photoresist Material: Impact of UV Laser Intensity on the Cured Line Width

NASA Astrophysics Data System (ADS)

Mohammed, Mohammed Ziauddin; Mourad, Abdel-Hamid I.; Khashan, Saud A.

2018-06-01

The application of maskless lithography technique on negative photoresist material is investigated in this study. The equipment used in this work is designed and built especially for maskless lithography applications. The UV laser of 405 nm wavelength with 0.85 Numerical Aperture is selected for direct laser writing. All the samples are prepared on a glass substrate. Samples are tested at different UV laser intensities and different stage velocities in order to study the impact on patterned line width. Three cases of spin coated layers of thickness 90 μm, 40 μm, and 28 μm on the substrate are studied. The experimental results show that line width has a generally increasing trend with intensity. However, a decreasing trend was observed for increasing velocity. The overall performance shows that the mr-DWL material is suitable for direct laser writing systems.

Maskless Lithography Using Negative Photoresist Material: Impact of UV Laser Intensity on the Cured Line Width

NASA Astrophysics Data System (ADS)

Mohammed, Mohammed Ziauddin; Mourad, Abdel-Hamid I.; Khashan, Saud A.

2018-04-01

The application of maskless lithography technique on negative photoresist material is investigated in this study. The equipment used in this work is designed and built especially for maskless lithography applications. The UV laser of 405 nm wavelength with 0.85 Numerical Aperture is selected for direct laser writing. All the samples are prepared on a glass substrate. Samples are tested at different UV laser intensities and different stage velocities in order to study the impact on patterned line width. Three cases of spin coated layers of thickness 90 μm, 40 μm, and 28 μm on the substrate are studied. The experimental results show that line width has a generally increasing trend with intensity. However, a decreasing trend was observed for increasing velocity. The overall performance shows that the mr-DWL material is suitable for direct laser writing systems.

Electron Beam/Optical Hybrid Lithography For The Production Of Gallium Arsenide Monolithic Microwave Integrated Circuits (Mimics)

NASA Astrophysics Data System (ADS)

Nagarajan, Rao M.; Rask, Steven D.

1988-06-01

A hybrid lithography technique is described in which selected levels are fabricated by high resolution direct write electron beam lithography and all other levels are fabricated optically. This technique permits subhalf micron geometries and the site-by-site alignment for each field written by electron beam lithography while still maintaining the high throughput possible with optical lithography. The goal is to improve throughput and reduce overall cost of fabricating MIMIC GaAS chips without compromising device performance. The lithography equipment used for these experiments is the Cambridge Electron beam vector scan system EBMF 6.4 capable of achieving ultra high current densities with a beam of circular cross section and a gaussian intensity profile operated at 20 kev. The optical aligner is a Karl Suss Contact aligner. The flexibility of the Cambridge electron beam system is matched to the less flexible Karl Suss contact aligner. The lithography related factors, such as image placement, exposure and process related analyses, which influence overlay, pattern quality and performance, are discussed. A process chip containing 3.2768mm fields in an eleven by eleven array was used for alignment evaluation on a 3" semi-insulating GaAS wafer. Each test chip contained five optical verniers and four Prometrix registration marks per field along with metal bumps for alignment marks. The process parameters for these chips are identical to those of HEMT/epi-MESFET ohmic contact and gate layer processes. These layers were used to evaluate the overlay accuracy because of their critical alignment and dimensional control requirements. Two cases were examined: (1) Electron beam written gate layers aligned to optically imaged ohmic contact layers and (2) Electron beam written gate layers aligned to electron beam written ohmic contact layers. The effect of substrate charging by the electron beam is also investigated. The resulting peak overlay error accuracies are: (1) Electron beam to optical with t 0.2μm (2 sigma) and (2) Electron beam to electron beam with f 0.lμm (2 sigma). These results suggest that the electron beam/optical hybrid lithography techniques could be used for MIMIC volume production as alignment tolerances required by GaAS chips are met in both cases. These results are discussed in detail.

Performance evaluation of nonchemically amplified negative tone photoresists for e-beam and EUV lithography

NASA Astrophysics Data System (ADS)

Singh, Vikram; Satyanarayana, Vardhineedi Sri Venkata; Batina, Nikola; Reyes, Israel Morales; Sharma, Satinder K.; Kessler, Felipe; Scheffer, Francine R.; Weibel, Daniel E.; Ghosh, Subrata; Gonsalves, Kenneth E.

2014-10-01

Although extreme ultraviolet (EUV) lithography is being considered as one of the most promising next-generation lithography techniques for patterning sub-20 nm features, the development of suitable EUV resists remains one of the main challenges confronting the semiconductor industry. The goal is to achieve sub-20 nm line patterns having low line edge roughness (LER) of <1.8 nm and a sensitivity of 5 to 20 mJ/cm2. The present work demonstrates the lithographic performance of two nonchemically amplified (n-CARs) negative photoresists, MAPDST homopolymer and MAPDST-MMA copolymer, prepared from suitable monomers containing the radiation sensitive sulfonium functionality. Investigations into the effect of several process parameters are reported. These include spinning conditions to obtain film thicknesses <50 nm, baking regimes, exposure conditions, and the resulting surface topographies. The effect of these protocols on sensitivity, contrast, and resolution has been assessed for the optimization of 20 nm features and the corresponding LER/line width roughness. These n-CARs have also been found to possess high etch resistance. The etch durability of MAPDST homopolymer and MAPDST-MMA copolymer (under SF6 plasma chemistry) with respect to the silicon substrate are 7.2∶1 and 8.3∶1, respectively. This methodical investigation will provide guidance in designing new resist materials with improved efficiency for EUVL through polymer microstructure engineering.

Multicellular Vascularized Engineered Tissues through User-Programmable Biomaterial Photodegradation.

PubMed

Arakawa, Christopher K; Badeau, Barry A; Zheng, Ying; DeForest, Cole A

2017-10-01

A photodegradable material-based approach to generate endothelialized 3D vascular networks within cell-laden hydrogel biomaterials is introduced. Exploiting multiphoton lithography, microchannel networks spanning nearly all size scales of native human vasculature are readily generated with unprecedented user-defined 4D control. Intraluminal channel architectures of synthetic vessels are fully customizable, providing new opportunities for next-generation microfluidics and directed cell function. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Planar techniques for fabricating X-ray diffraction gratings and zone plates

NASA Technical Reports Server (NTRS)

Smith, H. I.; Anderson, E. H.; Hawryluk, A. M.; Schattenburg, M. L.

1984-01-01

The state of current planar techniques in the fabrication of Fresnel zone plates and diffraction gratings is reviewed. Among the fabrication techniques described are multilayer resist techniques; scanning electron beam lithography; and holographic lithography. Consideration is also given to: X-ray lithography; ion beam lithography; and electroplating. SEM photographs of the undercut profiles obtained in a type AZ 135OB photoresistor by holographic lithography are provided.

Directed Nanopatterning with Nonlinear Laser Lithography

NASA Astrophysics Data System (ADS)

Tokel, Onur; Yavuz, Ozgun; Ergecen, Emre; Pavlov, Ihor; Makey, Ghaith; Ilday, Fatih Omer

In spite of the successes of maskless optical nanopatterning methods, it remains extremely challenging to create any isotropic, periodic nanopattern. Further, available optical techniques lack the long-range coverage and high periodicity demanded by photonics and photovoltaics applications. Here, we provide a novel solution with Nonlinear Laser Lithography (NLL) approach. Notably, we demonstrate that self-organized nanopatterns can be produced in all possible Bravais lattice types. Further, we show that carefully chosen defects or structued noise can direct NLL symmetries. Exploitation of directed self-organizatio to select or guide to predetermined symmetries is a new capability. Predictive capabilities for such far-from-equilibrium, dissipative systems is very limited due to a lack of experimental systems with predictive models. Here we also present a completely predictive model, and experimentally confirm that the emergence of motifs can be regulated by engineering defects, while the polarization of the ultrafast laser prescribes lattice symmetry, which in turn reinforces translational invariance. Thus, NLL enables a novel, maskless nanofabrication approach, where laser-induced nanopatterns can be rapidly created in any lattice symmetry

Development of a Wafer Positioning System for the Sandia Extreme Ultraviolet Lithography Tool

NASA Technical Reports Server (NTRS)

Wronosky, John B.; Smith, Tony G.; Darnold, Joel R.

1996-01-01

A wafer positioning system was recently developed by Sandia National Laboratories for an Extreme Ultraviolet Lithography (EUVL) tool. The system, which utilizes a magnetically levitated fine stage to provide ultra-precise positioning in all six degrees of freedom, incorporates technological improvements resulting from four years of prototype development. This paper describes the design, implementation, and functional capability of the system. Specifics regarding control system electronics, including software and control algorithm structure, as well as performance design goals and test results are presented. Potential system enhancements, some of which are in process, are also discussed.

Results from a new 193nm die-to-database reticle inspection platform

NASA Astrophysics Data System (ADS)

Broadbent, William H.; Alles, David S.; Giusti, Michael T.; Kvamme, Damon F.; Shi, Rui-fang; Sousa, Weston L.; Walsh, Robert; Xiong, Yalin

2010-05-01

A new 193nm wavelength high resolution reticle defect inspection platform has been developed for both die-to-database and die-to-die inspection modes. In its initial configuration, this innovative platform has been designed to meet the reticle qualification requirements of the IC industry for the 22nm logic and 3xhp memory generations (and shrinks) with planned extensions to the next generation. The 22nm/3xhp IC generation includes advanced 193nm optical lithography using conventional RET, advanced computational lithography, and double patterning. Further, EUV pilot line lithography is beginning. This advanced 193nm inspection platform has world-class performance and the capability to meet these diverse needs in optical and EUV lithography. The architecture of the new 193nm inspection platform is described. Die-to-database inspection results are shown on a variety of reticles from industry sources; these reticles include standard programmed defect test reticles, as well as advanced optical and EUV product and product-like reticles. Results show high sensitivity and low false and nuisance detections on complex optical reticle designs and small feature size EUV reticles. A direct comparison with the existing industry standard 257nm wavelength inspection system shows measurable sensitivity improvement for small feature sizes

Recent advances in engineering microparticles and their nascent utilization in biomedical delivery and diagnostic applications.

PubMed

Choi, Andrew; Seo, Kyoung Duck; Kim, Do Wan; Kim, Bum Chang; Kim, Dong Sung

2017-02-14

Complex microparticles (MPs) bearing unique characteristics such as well-tailored sizes, various morphologies, and multi-compartments have been attempted to be produced by many researchers in the past decades. However, a conventionally used method of fabricating MPs, emulsion polymerization, has a limitation in achieving the aforementioned characteristics and several approaches such as the microfluidics-assisted (droplet-based microfluidics and flow lithography-based microfluidics), electrohydrodynamics (EHD)-based, centrifugation-based, and template-based methods have been recently suggested to overcome this limitation. The outstanding features of complex MPs engineered through these suggested methods have provided new opportunities for MPs to be applied in a wider range of applications including cell carriers, drug delivery agents, active pigments for display, microsensors, interface stabilizers, and catalyst substrates. Overall, the engineered MPs expose their potential particularly in the field of biomedical engineering as the increased complexity in the engineered MPs fulfills well the requirements of the high-end applications. This review outlines the current trends of newly developed techniques used for engineered MPs fabrication and focuses on the current state of engineered MPs in biomedical applications.

Evaluating practical vs. theoretical inspection system capability with a new programmed defect test mask designed for 3X and 4X technology nodes

NASA Astrophysics Data System (ADS)

Glasser, Joshua; Pratt, Tim

2008-10-01

Programmed defect test masks serve the useful purpose of evaluating inspection system sensitivity and capability. It is widely recognized that when evaluating inspection system capability, it is important to understand the actual sensitivity of the inspection system in production; yet unfortunately we have observed that many test masks are a more accurate judge of theoretical sensitivity rather than real-world usable capability. Use of ineffective test masks leave the purchaser of inspection equipment open to the risks of over-estimating the capability of their inspection solution and overspecifying defect sensitivity to their customers. This can result in catastrophic yield loss for device makers. In this paper we examine some of the lithography-related technology advances which place an increasing burden on mask inspection complexity, such as MEEF, defect printability estimation, aggressive OPC, double patterning, and OPC jogs. We evaluate the key inspection system component contributors to successful mask inspection, including what can "go wrong" with these components. We designed and fabricated a test mask which both (a) more faithfully represents actual production use cases; and (b) stresses the key components of the inspection system. This mask's patterns represent 32nm, 36nm, and 45nm logic and memory technology including metal and poly like background patterns with programmed defects. This test mask takes into consideration requirements of advanced lithography, such as MEEF, defect printability, assist features, nearly-repetitive patterns, and data preparation. This mask uses patterns representative of 32nm, 36nm, and 45nm logic, flash, and DRAM technology. It is specifically designed to have metal and poly like background patterns with programmed defects. The mask is complex tritone and was designed for annular immersion lithography.

State-of-the-art EUV materials and processes for the 7nm node and beyond

NASA Astrophysics Data System (ADS)

Buitrago, Elizabeth; Meeuwissen, Marieke; Yildirim, Oktay; Custers, Rolf; Hoefnagels, Rik; Rispens, Gijsbert; Vockenhuber, Michaela; Mochi, Iacopo; Fallica, Roberto; Tasdemir, Zuhal; Ekinci, Yasin

2017-03-01

Extreme ultraviolet lithography (EUVL, λ = 13.5 nm) being the most likely candidate to manufacture electronic devices for future technology nodes is to be introduced in high volume manufacturing (HVM) at the 7 nm logic node, at least at critical lithography levels. With this impending introduction, it is clear that excellent resist performance at ultra-high printing resolutions (below 20 nm line/space L/S) is ever more pressing. Nonetheless, EUVL has faced many technical challenges towards this paradigm shift to a new lithography wavelength platform. Since the inception of chemically amplified resists (CARs) they have been the base upon which state-of-the art photoresist technology has been developed from. Resist performance as measured in terms of printing resolution (R), line edge roughness (LER), sensitivity (D or exposure dose) and exposure latitude (EL) needs to be improved but there are well known trade-off relationships (LRS trade-off) among these parameters for CARs that hamper their simultaneous enhancement. Here, we present some of the most promising EUVL materials tested by EUV interference lithography (EUV-IL) with the aim of resolving features down to 11 nm half-pitch (HP), while focusing on resist performance at 16 and 13 nm HP as needed for the 7 and 5 nm node, respectively. EUV-IL has enabled the characterization and development of new resist materials before commercial EUV exposure tools become available and is therefore a powerful research and development tool. With EUV-IL, highresolution periodic images can be printed by the interference of two or more spatially coherent beams through a transmission-diffraction grating mask. For this reason, our experiments have been performed by EUV-IL at Swiss Light Source (SLS) synchrotron facility located at the Paul Scherrer Institute (PSI). Having the opportunity to test hundreds of EUVL materials from vendors and research partners from all over the world, PSI is able to give a global update on some of the most promising materials tested.

NASA Tech Briefs, January 2004

NASA Technical Reports Server (NTRS)

2004-01-01

Topics covered include: Multisensor Instrument for Real-Time Biological Monitoring; Sensor for Monitoring Nanodevice-Fabrication Plasmas; Backed Bending Actuator; Compact Optoelectronic Compass; Micro Sun Sensor for Spacecraft; Passive IFF: Autonomous Nonintrusive Rapid Identification of Friendly Assets; Finned-Ladder Slow-Wave Circuit for a TWT; Directional Radio-Frequency Identification Tag Reader; Integrated Solar-Energy-Harvesting and -Storage Device; Event-Driven Random-Access-Windowing CCD Imaging System; Stroboscope Controller for Imaging Helicopter Rotors; Software for Checking State-charts; Program Predicts Broadband Noise from a Turbofan Engine; Protocol for a Delay-Tolerant Data-Communication Network; Software Implements a Space-Mission File-Transfer Protocol; Making Carbon-Nanotube Arrays Using Block Copolymers: Part 2; Modular Rake of Pitot Probes; Preloading To Accelerate Slow-Crack-Growth Testing; Miniature Blimps for Surveillance and Collection of Samples; Hybrid Automotive Engine Using Ethanol-Burning Miller Cycle; Fabricating Blazed Diffraction Gratings by X-Ray Lithography; Freeze-Tolerant Condensers; The StarLight Space Interferometer; Champagne Heat Pump; Controllable Sonar Lenses and Prisms Based on ERFs; Measuring Gravitation Using Polarization Spectroscopy; Serial-Turbo-Trellis-Coded Modulation with Rate-1 Inner Code; Enhanced Software for Scheduling Space-Shuttle Processing; Bayesian-Augmented Identification of Stars in a Narrow View; Spacecraft Orbits for Earth/Mars-Lander Radio Relay; and Self-Inflatable/Self-Rigidizable Reflectarray Antenna.

Manufacturability study of masks created by inverse lithography technology (ILT)

NASA Astrophysics Data System (ADS)

Martin, Patrick M.; Progler, C. J.; Xiao, G.; Gray, R.; Pang, L.; Liu, Y.

2005-11-01

As photolithography is pushed to fabricate deep-sub wavelength devices for 90nm, 65nm and smaller technology nodes using available exposure tools (i.e., 248nm, 193nm steppers), photomask capability is becoming extremely critical. For example, PSM masks require more complicated processing; aggressive OPC makes the writing time longer and sometimes unpredictable; and, high MEEF imposes much more stringent demands on mask quality. Therefore, in order for any new lithography technology to be adopted into production, mask manufacturability must be studied thoroughly and carefully. In this paper we will present the mask manufacturability study on mask patterns created using Inverse Lithography Technology (ILT). Unlike conventional OPC methodologies, ILT uses a unique outcome-based technology to mathematically determine the mask features that produce the desired on-wafer results. ILT solves the most critical litho challenges of the deep sub-wavelength era. Potential benefits include: higher yield; expanded litho process windows; superb pattern fidelity at 90, 65 & 45-nm nodes; and reduced time-to-silicon - all without changing the existing lithography infrastructure and design-to-silicon flow. In this study a number of cell structures were selected and used as test patterns. "Luminized patterns" were generated for binary mask and attenuated phase-shift mask. Both conventional OPC patterns and "luminized patterns" were put on a test reticle side by side, and they all have a number of variations in term of correction aggressivity level and mask complexity. Mask manufacturability, including data fracturing, writing time, mask inspection, and metrology were studied. The results demonstrate that, by optimizing the inspection recipe, masks created using ILT technology can be made and qualified using current processes with a reasonable turn-around time.

Three dimensional fabrication at small size scales

PubMed Central

Leong, Timothy G.; Zarafshar, Aasiyeh M.; Gracias, David H.

2010-01-01

Despite the fact that we live in a three-dimensional (3D) world and macroscale engineering is 3D, conventional sub-mm scale engineering is inherently two-dimensional (2D). New fabrication and patterning strategies are needed to enable truly three-dimensionally-engineered structures at small size scales. Here, we review strategies that have been developed over the last two decades that seek to enable such millimeter to nanoscale 3D fabrication and patterning. A focus of this review is the strategy of self-assembly, specifically in a biologically inspired, more deterministic form known as self-folding. Self-folding methods can leverage the strengths of lithography to enable the construction of precisely patterned 3D structures and “smart” components. This self-assembling approach is compared with other 3D fabrication paradigms, and its advantages and disadvantages are discussed. PMID:20349446

The Introduction and Early Use of Lithography in the United States.

ERIC Educational Resources Information Center

Barnhill, Georgia B.

This paper discusses the use of lithography in the United States in the early 1800s. Highlights include: the development of lithography in Germany between 1796 and 1798; early expectations for lithography; competition against the existing technology for the production of images--relief prints and copper-plate engravings; examples of 18th-century…

Materials Design for Block Copolymer Lithography

NASA Astrophysics Data System (ADS)

Sweat, Daniel Patrick

Block copolymers (BCPs) have attracted a great deal of scientific and technological interest due to their ability to spontaneously self-assemble into dense periodic nanostructures with a typical length scale of 5 to 50 nm. The use of self-assembled BCP thin-films as templates to form nanopatterns over large-area is referred to as BCP lithography. Directed self-assembly of BCPs is now viewed as a viable candidate for sub-20 nm lithography by the semiconductor industry. However, there are multiple aspects of assembly and materials design that need to be addressed in order for BCP lithography to be successful. These include substrate modification with polymer brushes or mats, tailoring of the block copolymer chemistry, understanding thin-film assembly and developing epitaxial like methods to control long range alignment. The rational design, synthesis and self-assembly of block copolymers with large interaction parameters (chi) is described in the first part of this dissertation. Two main blocks were chosen for introducing polarity into the BCP system, namely poly(4-hydroxystyrene) and poly(2-vinylpyridine). Each of these blocks are capable of ligating Lewis acids which can increase the etch contrast between the blocks allowing for facile pattern transfer to the underlying substrate. These BCPs were synthesized by living anionic polymerization and showed excellent control over molecular weight and dispersity, providing access to sub 5-nm domain sizes. Polymer brushes consist of a polymer chain with one end tethered to the surface and have wide applicability in tuning surface energy, forming responsive surfaces and increasing biocompatibility. In the second part of the dissertation, we present a universal method to grow dense polymer brushes on a wide range of substrates and combine this chemistry with BCP assembly to fabricate nanopatterned polymer brushes. This is the first demonstration of introducing additional functionality into a BCP directing layer and opens up a wide slew of applications from directed self-assembly to biomaterial engineering.

Cell laden hydrogel construct on-a-chip for mimicry of cardiac tissue in-vitro study

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

Ghiaseddin, Ali; Pouri, Hossein; Soleimani, Masoud

Since the leading cause of death are cardiac diseases, engineered heart tissue (EHT) is one of the most appealing topics defined in tissue engineering and regenerative medicine fields. The importance of EHT is not only for heart regeneration but also for in vitro developing of cardiology. Cardiomyocytes could grow and commit more naturally in their microenvironment rather than traditional cultivation. Thus, this research tried to develop a set up on-a-chip to produce EHT based on chitosan hydrogel. Micro-bioreactor was hydrodynamically designed and simulated by COMSOL and produced via soft lithography process. Chitosan hydrogel was also prepared, adjusted, and assessed by XRD,more » FTIR and also its degradation rate and swelling ratio were determined. Finally, hydrogels in which mice cardiac progenitor cells (CPC) were loaded were injected into the micro-device chambers and cultured. Each EHT in every chamber was evaluated separately. Prepared EHTs showed promising results that expanded in them CPCs and work as an integrated syncytium. High cell density culture was the main accomplishment of this study. - Highlights: • An engineered heart tissue in its microenvironment at a perfused micro-bioreactor is proposed. • Cell proliferation of cardiac cells in high cell density is achievable in setup while sacrificing hydrogel is degrading. • 16 distinct heart tissue constructs in each run reduce the time and cost and increase the test results accuracy.« less

Ion projection lithography: November 2000 status and sub-70-nm prospects

NASA Astrophysics Data System (ADS)

Kaesmaier, Rainer; Wolter, Andreas; Loeschner, Hans; Schunck, Stefan

2000-10-01

Among all next generation lithography (NGL) options Ion Projection Lithography (IPL) offers the smallest (particle) wavelength of 5x10- 5nm (l00keV Helium ions). Thus, 4x reduction ion-optics has diffraction limits <3nm even when using a numerical aperture as low as NAequals10-5. As part of the European MEDEA IPL project headed by Infineon Technologies wide field ion-optics have been designed by IMS- Vienna with predicted resolution of 50nm within a 12.5mm exposure field. The ion-optics part of the PDT tool (PDT-IOS) has been realized and assembled. In parallel to the PDT-IOS effort, at Leica Jena a test bench for a vertical vacuum 300mm-wafer stage has been realized. Operation of magnetic bearing supported stage movement has already been demonstrated. As ASML vacuum compatible optical wafer alignment system, with 3nm(3(sigma) ) precision demonstrated in air, has been integrated to this wafer test bench system recently. Parallel to the IPL tool development, Infineon Technologies Mask House and the Institute for Microelectronics Stuttgart are intensively working on the development of IPL stencil masks with success in producing 150mm and 200mm stencil masks as reported elsewhere. This paper is focused on information about the status of the PDT-IOS tool.

Novel organosilicone materials and patterning techniques for nanoimprint lithography

NASA Astrophysics Data System (ADS)

Pina, Carlos Alberto

Nanoimprint Lithography (NIL) is a high-throughput patterning technique that allows the fabrication of nanostructures with great precision. It has been listed on the International Technology Roadmap for Semiconductors (ITRS) as a candidate technology for future generation Si chip manufacturing. In nanoimprint Lithography a resist material, e.g. a thermoplastic polymer, is placed in contact with a mold and then mechanically deformed under an applied load to transfer the nano-features on the mold surface into the resist. The success of NIL relies heavily in the capability of fabricating nanostructures on different types of materials. Thus, a key factor for NIL implementation in industrial settings is the development of advanced materials suitable as the nanoimprint resist. This dissertation focuses on the engineering of new polymer materials suitable as NIL resist. A variety of silicone-based polymer precursors were synthesized and formulated for NIL applications. High throughput and high yield nanopatterning was successfully achieved. Furthermore, additional capabilities of the developed materials were explored for a range of NIL applications such as their use as flexible, UV-transparent stamps and silicon compatible etching layers. Finally, new strategies were investigated to expand the NIL potentiality. High throughput, non-residual layer imprinting was achieved with the newly developed resist materials. In addition, several strategies were designed for the precise control of nanoscale size patterned structures with multifunctional resist systems by post-imprinting modification of the pattern size. These developments provide NIL with a new set of tools for a variety of additional important applications.

Engineering optical properties using plasmonic nanostructures

NASA Astrophysics Data System (ADS)

Tamma, Venkata Ananth

Plasmonic nanostructures can be engineered to take on unusual optical properties not found in natural materials. The optical responses of plasmonic materials are functions of the structural parameters and symmetry of the nanostructures, material parameters of the nanostructure and its surroundings and the incidence angle, frequency and polarization state of light. The scattering and hence the visibility of an object could be reduced by coating it with a plasmonic material. In this thesis, presented is an optical frequency scattering cancelation device composed of a silicon nanorod coated by a plasmonic gold nanostructure. The principle of operation was theoretically analyzed using Mie theory and the device design was verified by extensive numerical simulations. The device was fabricated using a combination of nanofabrication techniques such as electron beam lithography and focused ion beam milling. The optical responses of the scattering cancelation device and a control sample of bare silicon rod were directly visualized using near-field microscopy coupled with heterodyne interferometric detection. The experimental results were analyzed and found to match very well with theoretical prediction from numerical simulations thereby validating the design principles and our implementation. Plasmonic nanostructures could be engineered to exhibit unique optical properties such as Fano resonance characterized by narrow asymmetrical lineshape. We present dynamic tuning and symmetry lowering of Fano resonances in plasmonic nanostructures fabricated on flexible substrates. The tuning of Fano resonance was achieved by application of uniaxial mechanical stress. The design of the nanostructures was facilitated by extensive numerical simulations and the symmetry lowering was analyzed using group theoretical methods. The nanostructures were fabricated using electron beam lithography and optically characterized for various mechanical stress. The experimental results were in good agreement with the numerical simulations. The mechanically tunable plasmonic nanostructure could serve as a platform for dynamically tunable nanophotonic devices such as sensors and tunable filters.

Immersion lithography defectivity analysis at DUV inspection wavelength

NASA Astrophysics Data System (ADS)

Golan, E.; Meshulach, D.; Raccah, N.; Yeo, J. Ho.; Dassa, O.; Brandl, S.; Schwarz, C.; Pierson, B.; Montgomery, W.

2007-03-01

Significant effort has been directed in recent years towards the realization of immersion lithography at 193nm wavelength. Immersion lithography is likely a key enabling technology for the production of critical layers for 45nm and 32nm design rule (DR) devices. In spite of the significant progress in immersion lithography technology, there remain several key technology issues, with a critical issue of immersion lithography process induced defects. The benefits of the optical resolution and depth of focus, made possible by immersion lithography, are well understood. Yet, these benefits cannot come at the expense of increased defect counts and decreased production yield. Understanding the impact of the immersion lithography process parameters on wafer defects formation and defect counts, together with the ability to monitor, control and minimize the defect counts down to acceptable levels is imperative for successful introduction of immersion lithography for production of advanced DR's. In this report, we present experimental results of immersion lithography defectivity analysis focused on topcoat layer thickness parameters and resist bake temperatures. Wafers were exposed on the 1150i-α-immersion scanner and 1200B Scanner (ASML), defect inspection was performed using a DUV inspection tool (UVision TM, Applied Materials). Higher sensitivity was demonstrated at DUV through detection of small defects not detected at the visible wavelength, indicating on the potential high sensitivity benefits of DUV inspection for this layer. The analysis indicates that certain types of defects are associated with different immersion process parameters. This type of analysis at DUV wavelengths would enable the optimization of immersion lithography processes, thus enabling the qualification of immersion processes for volume production.

Manipulation of heat-diffusion channel in laser thermal lithography.

PubMed

Wei, Jingsong; Wang, Yang; Wu, Yiqun

2014-12-29

Laser thermal lithography is a good alternative method for forming small pattern feature size by taking advantage of the structural-change threshold effect of thermal lithography materials. In this work, the heat-diffusion channels of laser thermal lithography are first analyzed, and then we propose to manipulate the heat-diffusion channels by inserting thermal conduction layers in between channels. Heat-flow direction can be changed from the in-plane to the out-of-plane of the thermal lithography layer, which causes the size of the structural-change threshold region to become much smaller than the focused laser spot itself; thus, nanoscale marks can be obtained. Samples designated as "glass substrate/thermal conduction layer/thermal lithography layer (100 nm)/thermal conduction layer" are designed and prepared. Chalcogenide phase-change materials are used as thermal lithography layer, and Si is used as thermal conduction layer to manipulate heat-diffusion channels. Laser thermal lithography experiments are conducted on a home-made high-speed rotation direct laser writing setup with 488 nm laser wavelength and 0.90 numerical aperture of converging lens. The writing marks with 50-60 nm size are successfully obtained. The mark size is only about 1/13 of the focused laser spot, which is far smaller than that of the light diffraction limit spot of the direct laser writing setup. This work is useful for nanoscale fabrication and lithography by exploiting the far-field focusing light system.

Honing the accuracy of extreme-ultraviolet optical system testing: at-wavelength and visible-light measurements of the ETS Set-2 projection optic

NASA Astrophysics Data System (ADS)

Goldberg, Kenneth A.; Naulleau, Patrick P.; Bokor, Jeffrey; Chapman, Henry N.

2002-07-01

As the quality of optical systems for extreme ultraviolet lithography improves, high-accuracy wavefront metrology for alignment and qualification becomes ever more important. To enable the development of diffraction-limited EUV projection optics, visible-light and EUV interferometries must work in close collaboration. We present a detailed comparison of EUV and visible-light wavefront measurements performed across the field of view of a lithographic-quality EUV projection optical system designed for use in the Engineering Test Stand developed by the Virtual National Laboratory and the EUV Limited Liability Company. The comparisons reveal that the present level of RMS agreement lies in the 0.3-0.4-nm range. Astigmatism is the most significant aberration component for the alignment of this optical system; it is also the dominant term in the discrepancy, and the aberration with the highest measurement uncertainty. With EUV optical systems requiring total wavefront quality in the (lambda) EUV/50 range, and even higher surface-figure quality for the individual mirror elements, improved accuracy through future comparisons, and additional studies, are required.

Vector optical fields with bipolar symmetry of linear polarization.

PubMed

Pan, Yue; Li, Yongnan; Li, Si-Min; Ren, Zhi-Cheng; Si, Yu; Tu, Chenghou; Wang, Hui-Tian

2013-09-15

We focus on a new kind of vector optical field with bipolar symmetry of linear polarization instead of cylindrical and elliptical symmetries, enriching members of family of vector optical fields. We design theoretically and generate experimentally the demanded vector optical fields and then explore some novel tightly focusing properties. The geometric configurations of states of polarization provide additional degrees of freedom assisting in engineering the field distribution at the focus to the specific applications such as lithography, optical trapping, and material processing.

The capability of lithography simulation based on MVM-SEM® system

NASA Astrophysics Data System (ADS)

Yoshikawa, Shingo; Fujii, Nobuaki; Kanno, Koichi; Imai, Hidemichi; Hayano, Katsuya; Miyashita, Hiroyuki; Shida, Soichi; Murakawa, Tsutomu; Kuribara, Masayuki; Matsumoto, Jun; Nakamura, Takayuki; Matsushita, Shohei; Hara, Daisuke; Pang, Linyong

2015-10-01

The 1Xnm technology node lithography is using SMO-ILT, NTD or more complex pattern. Therefore in mask defect inspection, defect verification becomes more difficult because many nuisance defects are detected in aggressive mask feature. One key Technology of mask manufacture is defect verification to use aerial image simulator or other printability simulation. AIMS™ Technology is excellent correlation for the wafer and standards tool for defect verification however it is difficult for verification over hundred numbers or more. We reported capability of defect verification based on lithography simulation with a SEM system that architecture and software is excellent correlation for simple line and space.[1] In this paper, we use a SEM system for the next generation combined with a lithography simulation tool for SMO-ILT, NTD and other complex pattern lithography. Furthermore we will use three dimension (3D) lithography simulation based on Multi Vision Metrology SEM system. Finally, we will confirm the performance of the 2D and 3D lithography simulation based on SEM system for a photomask verification.

Fabrication of 3D polymer photonic crystals for near-IR applications

NASA Astrophysics Data System (ADS)

Yao, Peng; Qiu, Liang; Shi, Shouyuan; Schneider, Garrett J.; Prather, Dennis W.; Sharkawy, Ahmed; Kelmelis, Eric

2008-02-01

Photonic crystals[1, 2] have stirred enormous research interest and became a growing enterprise in the last 15 years. Generally, PhCs consist of periodic structures that possess periodicity comparable with the wavelength that the PhCs are designed to modulate. If material and periodic pattern are properly selected, PhCs can be applied to many applications based on their unique properties, including photonic band gaps (PBG)[3], self-collimation[4], super prism[5], etc. Strictly speaking, PhCs need to possess periodicity in three dimensions to maximize their advantageous capabilities. However, many current research is based on scaled two-dimensional PhCs, mainly due to the difficulty of fabrication such three-dimensional PhCs. Many approaches have been explored for the fabrication of 3D photonic crystals, including layer-by-layer surface micromachining[6], glancing angle deposition[7], 3D micro-sculpture method[8], self-assembly[9] and lithographical methods[10-12]. Among them, lithographic methods became increasingly accepted due to low costs and precise control over the photonic crystal structure. There are three mostly developed lithographical methods, namely X-ray lithography[10], holographic lithography[11] and two-photon polymerization[12]. Although significant progress has been made in developing these lithography-based technologies, these approaches still suffer from significant disadvantages. X-ray lithography relies on an expensive radiation source. Holographic lithography lacks the flexibility to create engineered defects, and multi-photon polymerization is not suitable for parallel fabrication. In our previous work, we developed a multi-layer photolithography processes[13, 14] that is based on multiple resist application and enhanced absorption upon exposure. Using a negative lift-off resist (LOR) and 254nm DUV source, we have demonstrated fabrication of 3D arbitrary structures with feature size of several microns. However, severe intermixing problem occurred as we reduced the lattice constant for near-IR applications. In this work, we address this problem by employing SU8. The exposure is vertically confined by using a mismatched 220nm DUV source. Intermixing problem is eliminated due to more densely crosslinked resist molecules. Using this method, we have demonstrated 3D "woodpile" structure with 1.55μm lattice constant and a 2mm-by-2mm pattern area.

Accuracy and performance of 3D mask models in optical projection lithography

NASA Astrophysics Data System (ADS)

Agudelo, Viviana; Evanschitzky, Peter; Erdmann, Andreas; Fühner, Tim; Shao, Feng; Limmer, Steffen; Fey, Dietmar

2011-04-01

Different mask models have been compared: rigorous electromagnetic field (EMF) modeling, rigorous EMF modeling with decomposition techniques and the thin mask approach (Kirchhoff approach) to simulate optical diffraction from different mask patterns in projection systems for lithography. In addition, each rigorous model was tested for two different formulations for partially coherent imaging: The Hopkins assumption and rigorous simulation of mask diffraction orders for multiple illumination angles. The aim of this work is to closely approximate results of the rigorous EMF method by the thin mask model enhanced with pupil filtering techniques. The validity of this approach for different feature sizes, shapes and illumination conditions is investigated.

High-power modular LED-based illumination systems for mask-aligner lithography.

PubMed

Bernasconi, Johana; Scharf, Toralf; Vogler, Uwe; Herzig, Hans Peter

2018-04-30

Mask-aligner lithography is traditionally performed using mercury arc lamps with wavelengths ranging from 250 nm to 600 nm with intensity peaks at the i, g and h lines. Since mercury arc lamps present several disadvantages, it is of interest to replace them with high power light emitting diodes (LEDs), which recently appeared on the market at those wavelengths. In this contribution, we present a prototype of an LED-based mask-aligner illumination. An optical characterization is made and the prototype is tested in a mask-aligner. Very good performances are demonstrated. The measured uniformity in the mask plane is 2.59 ± 0.24 % which is within the uniformity of the standard lamp. Print tests show resolution of 1 micron in contact printing and of 3 microns in proximity printing with a proximity gap of 30 microns.

Polarization manipulation in single refractive prism based holography lithography

NASA Astrophysics Data System (ADS)

Xiong, Wenjie; Xu, Yi; Xiao, Yujian; Lv, Xiaoxu; Wu, Lijun

2015-01-01

We propose theoretically and demonstrate experimentally a simple but effective strategy for polarization manipulation in single refractive prism based holographic lithography. By tuning the polarization of a single laser beam, we can obtain the pill shape interference pattern with a high-contrast where a complex optical setup and multiple polarizers are needed in the conventional holography lithography. Fabrication of pill shape two-dimensional polymer photonic crystals using one beam and one shoot holography lithography is shown as an example to support our theoretical results. This integrated polarization manipulation technique can release the crucial stability restrictions imposed on the multiple beams holography lithography.

A Microfabricated Involute-Foil Regenerator for Stirling Engines

NASA Technical Reports Server (NTRS)

Tew, Roy; Ibrahim, Mounir; Danila, Daniel; Simon, Terrence; Mantell, Susan; Sun, Liyong; Gedeon, David; Kelly, Kevin; McLean, Jeffrey; Qiu, Songgang

2007-01-01

A segmented involute-foil regenerator has been designed, microfabricated and tested in an oscillating-flow rig with excellent results. During the Phase I effort, several approximations of parallel-plate regenerator geometry were chosen as potential candidates for a new microfabrication concept. Potential manufacturers and processes were surveyed. The selected concept consisted of stacked segmented-involute-foil disks (or annular portions of disks), originally to be microfabricated from stainless-steel via the LiGA (lithography, electroplating, and molding) process and EDM. During Phase II, re-planning of the effort led to test plans based on nickel disks, microfabricated via the LiGA process, only. A stack of nickel segmented-involute-foil disks was tested in an oscillating-flow test rig. These test results yielded a performance figure of merit (roughly the ratio of heat transfer to pressure drop) of about twice that of the 90 percent random fiber currently used in small approx.100 W Stirling space-power convertors-in the Reynolds Number range of interest (50 to 100). A Phase III effort is now underway to fabricate and test a segmented-involute-foil regenerator in a Stirling convertor. Though funding limitations prevent optimization of the Stirling engine geometry for use with this regenerator, the Sage computer code will be used to help evaluate the engine test results. Previous Sage Stirling model projections have indicated that a segmented-involute-foil regenerator is capable of improving the performance of an optimized involute-foil engine by 6 to 9 percent; it is also anticipated that such involute-foil geometries will be more reliable and easier to manufacture with tight-tolerance characteristics, than random-fiber or wire-screen regenerators. Beyond the near-term Phase III regenerator fabrication and engine testing, other goals are (1) fabrication from a material suitable for high temperature Stirling operation (up to 850 C for current engines; up to 1200 C for a potential engine-cooler for a Venus mission), and (2) reduction of the cost of the fabrication process to make it more suitable for terrestrial applications of segmented involute foils. Past attempts have been made to use wrapped foils to approximate the large theoretical figures of merit projected for parallel plates. Such metal wrapped foils have never proved very successful, apparently due to the difficulties of fabricating wrapped-foils with uniform gaps and maintaining the gaps under the stress of time-varying temperature gradients during start-up and shut-down, and relatively-steady temperature gradients during normal operation. In contrast, stacks of involute-foil disks, with each disk consisting of multiple involute-foil segments held between concentric circular ribs, have relatively robust structures. The oscillating-flow rig tests of the segmented-involute-foil regenerator have demonstrated a shift in regenerator performance strongly in the direction of the theoretical performance of ideal parallel-plate regenerators.

A Microfabricated Involute-Foil Regenerator for Stirling Engines

NASA Technical Reports Server (NTRS)

Tew, Roy; Ibrahim, Mounir; Danila, Daniel; Simon, Terry; Mantell, Susan; Sun, Liyong; Gedeon, David; Kelly, Kevin; McLean, Jeffrey; Wood, Gary;

Patterning control strategies for minimum edge placement error in logic devices

NASA Astrophysics Data System (ADS)

Mulkens, Jan; Hanna, Michael; Slachter, Bram; Tel, Wim; Kubis, Michael; Maslow, Mark; Spence, Chris; Timoshkov, Vadim

2017-03-01

In this paper we discuss the edge placement error (EPE) for multi-patterning semiconductor manufacturing. In a multi-patterning scheme the creation of the final pattern is the result of a sequence of lithography and etching steps, and consequently the contour of the final pattern contains error sources of the different process steps. We describe the fidelity of the final pattern in terms of EPE, which is defined as the relative displacement of the edges of two features from their intended target position. We discuss our holistic patterning optimization approach to understand and minimize the EPE of the final pattern. As an experimental test vehicle we use the 7-nm logic device patterning process flow as developed by IMEC. This patterning process is based on Self-Aligned-Quadruple-Patterning (SAQP) using ArF lithography, combined with line cut exposures using EUV lithography. The computational metrology method to determine EPE is explained. It will be shown that ArF to EUV overlay, CDU from the individual process steps, and local CD and placement of the individual pattern features, are the important contributors. Based on the error budget, we developed an optimization strategy for each individual step and for the final pattern. Solutions include overlay and CD metrology based on angle resolved scatterometry, scanner actuator control to enable high order overlay corrections and computational lithography optimization to minimize imaging induced pattern placement errors of devices and metrology targets.

System design considerations for a production-grade, ESR-based x-ray lithography beamline

NASA Astrophysics Data System (ADS)

Kovacs, Stephen; Melore, Dan; Cerrina, Franco; Cole, Richard K.

1991-08-01

As electron storage ring (ESR) based x-ray lithography technology moves closer to becoming an industrial reality, more and more attention has been devoted to studying problem areas related to its application in the production environment. A principle component is the x-ray lithography beamline (XLBL) and its associated design requirements. XLBL, an x-ray radiation transport system, is one of the three major subunits in the ESR-based x-ray lithography system (XLS) and has a pivotal role in defining performance characteristics of the entire XLS. Its major functions are to transport the synchrotron orbital radiation (SOR) to the lithography target area with defined efficiency and to modify SOR into the spectral distribution defined by the lithography process window. These functions must be performed reliably in order to satisfy the required high production rate and ensure 0.25 micron resolution lithography conditions. In this paper the authors attempt to answer some specific questions that arise during the formulation of an XLBL system design. Three principle issues that are essential to formulating a design are (1) Radiation transport efficiency, (2) X-ray optical configurations in the beamline, (3) Beamline system configurations. Some practical solutions to thee problem areas are presented, and the effects of these parameters on lithography production rate are examined.

Looking into the crystal ball: future device learning using hybrid e-beam and optical lithography (Keynote Paper)

NASA Astrophysics Data System (ADS)

Steen, S. E.; McNab, S. J.; Sekaric, L.; Babich, I.; Patel, J.; Bucchignano, J.; Rooks, M.; Fried, D. M.; Topol, A. W.; Brancaccio, J. R.; Yu, R.; Hergenrother, J. M.; Doyle, J. P.; Nunes, R.; Viswanathan, R. G.; Purushothaman, S.; Rothwell, M. B.

2005-05-01

Semiconductor process development teams are faced with increasing process and integration complexity while the time between lithographic capability and volume production has remained more or less constant over the last decade. Lithography tools have often gated the volume checkpoint of a new device node on the ITRS roadmap. The processes have to be redeveloped after the tooling capability for the new groundrule is obtained since straight scaling is no longer sufficient. In certain cases the time window that the process development teams have is actually decreasing. In the extreme, some forecasts are showing that by the time the 45nm technology node is scheduled for volume production, the tooling vendors will just begin shipping the tools required for this technology node. To address this time pressure, IBM has implemented a hybrid-lithography strategy that marries the advantages of optical lithography (high throughput) with electron beam direct write lithography (high resolution and alignment capability). This hybrid-lithography scheme allows for the timely development of semiconductor processes for the 32nm node, and beyond. In this paper we will describe how hybrid lithography has enabled early process integration and device learning and how IBM applied e-beam & optical hybrid lithography to create the world's smallest working SRAM cell.

Plasmonic direct writing lithography with a macroscopical contact probe

NASA Astrophysics Data System (ADS)

Huang, Yuerong; Liu, Ling; Wang, Changtao; Chen, Weidong; Liu, Yunyue; Li, Ling

2018-05-01

In this work, we design a plasmonic direct writing lithography system with a macroscopical contact probe to achieve nanometer scale spots. The probe with bowtie-shaped aperture array adopts spring hinge and beam deflection method (BDM) to realize near-field lithography. Lithography results show that a macroscopical plasmonic contact probe can achieve a patterning resolution of around 75 nm at 365 nm wavelength, and demonstrate that the lithography system is promising for practical applications due to beyond the diffraction limit, low cost, and simplification of system configuration. CST calculations provide a guide for the design of recording structure and the arrangement of placing polarizer.

Physical Limitations in Lithography for Microelectronics.

ERIC Educational Resources Information Center

Flavin, P. G.

1981-01-01

Describes techniques being used in the production of microelectronics kits which have replaced traditional optical lithography, including contact and optical projection printing, and X-ray and electron beam lithography. Also includes limitations of each technique described. (SK)

Current nanoscience and nanoengineering at the Center for Nanoscale Science and Engineering

NASA Astrophysics Data System (ADS)

Hermann, A. M.; Singh, R. S.; Singh, V. P.

2006-07-01

The Center for Nanoscale Science and Engineering (CeNSE) at the University of Kentucky is a multidisciplinary group of faculty, students, and staff, with a shared vision and cutting-edge research facilities to study and develop materials and devices at the nanoscale. Current research projects at CeNSE span a number of diverse nanoscience thrusts in bio- engineering and medicine (nanosensors and nanoelectrodes, nanoparticle-based drug delivery), electronics (nanolithography, molecular electronics, nanotube FETs), nanotemplates for electronics and gas sensors (functionalization of carbon nanotubes, aligned carbon nanotube structures for gate-keeping, e-beam lithography with nanoscale precision), and nano--optoelectronics (nanoscale photonics for laser communications, quantum confinement in photovoltaic devices, and nanostructured displays). This paper provides glimpses of this research and future directions.

Tailoring plasmonic nanoparticles and fractal patterns

NASA Astrophysics Data System (ADS)

Rosa, Lorenzo; Juodkazis, Saulius

2011-12-01

We studied new three-dimensional tailoring of nano-particles by ion-beam and electron-beam lithographies, aiming for features and nano-gaps down to 10 nm size. Electron-beam patterning is demonstrated for 2D fabrication in combination with plasmonic metal deposition and lift-off, with full control of spectral features of plasmonic nano-particles and patterns on dielectric substrates. We present wide-angle bow-tie rounded nano-antennas whose plasmonic resonances achieve strong field enhancement at engineered wavelength range, and show how the addition of fractal patterns defined by standard electron beam lithography achieve light field enhancement from visible to far-IR spectral range and scalable up towards THz band. Field enhancement is evaluated by FDTD modeling on full-3D simulation domains using complex material models, showing the modeling method capabilities and the effect of staircase approximations on field enhancement and resonance conditions, especially at metal corners, where a minimum rounding radius of 2 nm is resolved and a five-fold reduction of spurious ringing at sharp corners is obtained by the use of conformal meshing.

Advancing three-dimensional MEMS by complimentary laser micro manufacturing

NASA Astrophysics Data System (ADS)

Palmer, Jeremy A.; Williams, John D.; Lemp, Tom; Lehecka, Tom M.; Medina, Francisco; Wicker, Ryan B.

2006-01-01

This paper describes improvements that enable engineers to create three-dimensional MEMS in a variety of materials. It also provides a means for selectively adding three-dimensional, high aspect ratio features to pre-existing PMMA micro molds for subsequent LIGA processing. This complimentary method involves in situ construction of three-dimensional micro molds in a stand-alone configuration or directly adjacent to features formed by x-ray lithography. Three-dimensional micro molds are created by micro stereolithography (MSL), an additive rapid prototyping technology. Alternatively, three-dimensional features may be added by direct femtosecond laser micro machining. Parameters for optimal femtosecond laser micro machining of PMMA at 800 nanometers are presented. The technical discussion also includes strategies for enhancements in the context of material selection and post-process surface finish. This approach may lead to practical, cost-effective 3-D MEMS with the surface finish and throughput advantages of x-ray lithography. Accurate three-dimensional metal microstructures are demonstrated. Challenges remain in process planning for micro stereolithography and development of buried features following femtosecond laser micro machining.

Silk protein nanowires patterned using electron beam lithography.

PubMed

Pal, Ramendra K; Yadavalli, Vamsi K

2018-08-17

Nanofabrication approaches to pattern proteins at the nanoscale are useful in applications ranging from organic bioelectronics to cellular engineering. Specifically, functional materials based on natural polymers offer sustainable and environment-friendly substitutes to synthetic polymers. Silk proteins (fibroin and sericin) have emerged as an important class of biomaterials for next generation applications owing to excellent optical and mechanical properties, inherent biocompatibility, and biodegradability. However, the ability to precisely control their spatial positioning at the nanoscale via high throughput tools continues to remain a challenge. In this study electron beam lithography (EBL) is used to provide nanoscale patterning using methacrylate conjugated silk proteins that are photoreactive 'photoresists' materials. Very low energy electron beam radiation can be used to pattern silk proteins at the nanoscale and over large areas, whereby such nanostructure fabrication can be performed without specialized EBL tools. Significantly, using conducting polymers in conjunction with these silk proteins, the formation of protein nanowires down to 100 nm is shown. These wires can be easily degraded using enzymatic degradation. Thus, proteins can be precisely and scalably patterned and doped with conducting polymers and enzymes to form degradable, organic bioelectronic devices.

L-shaped fiber-chip grating couplers with high directionality and low reflectivity fabricated with deep-UV lithography.

PubMed

Benedikovic, Daniel; Alonso-Ramos, Carlos; Pérez-Galacho, Diego; Guerber, Sylvain; Vakarin, Vladyslav; Marcaud, Guillaume; Le Roux, Xavier; Cassan, Eric; Marris-Morini, Delphine; Cheben, Pavel; Boeuf, Frédéric; Baudot, Charles; Vivien, Laurent

2017-09-01

Grating couplers enable position-friendly interfacing of silicon chips by optical fibers. The conventional coupler designs call upon comparatively complex architectures to afford efficient light coupling to sub-micron silicon-on-insulator (SOI) waveguides. Conversely, the blazing effect in double-etched gratings provides high coupling efficiency with reduced fabrication intricacy. In this Letter, we demonstrate for the first time, to the best of our knowledge, the realization of an ultra-directional L-shaped grating coupler, seamlessly fabricated by using 193 nm deep-ultraviolet (deep-UV) lithography. We also include a subwavelength index engineered waveguide-to-grating transition that provides an eight-fold reduction of the grating reflectivity, down to 1% (-20  dB). A measured coupling efficiency of -2.7  dB (54%) is achieved, with a bandwidth of 62 nm. These results open promising prospects for the implementation of efficient, robust, and cost-effective coupling interfaces for sub-micrometric SOI waveguides, as desired for large-volume applications in silicon photonics.

M&A For Lithography Of Sparse Arrays Of Sub-Micrometer Features

DOEpatents

Brueck, Steven R.J.; Chen, Xiaolan; Zaidi, Saleem; Devine, Daniel J.

1998-06-02

Methods and apparatuses are disclosed for the exposure of sparse hole and/or mesa arrays with line:space ratios of 1:3 or greater and sub-micrometer hole and/or mesa diameters in a layer of photosensitive material atop a layered material. Methods disclosed include: double exposure interferometric lithography pairs in which only those areas near the overlapping maxima of each single-period exposure pair receive a clearing exposure dose; double interferometric lithography exposure pairs with additional processing steps to transfer the array from a first single-period interferometric lithography exposure pair into an intermediate mask layer and a second single-period interferometric lithography exposure to further select a subset of the first array of holes; a double exposure of a single period interferometric lithography exposure pair to define a dense array of sub-micrometer holes and an optical lithography exposure in which only those holes near maxima of both exposures receive a clearing exposure dose; combination of a single-period interferometric exposure pair, processing to transfer resulting dense array of sub-micrometer holes into an intermediate etch mask, and an optical lithography exposure to select a subset of initial array to form a sparse array; combination of an optical exposure, transfer of exposure pattern into an intermediate mask layer, and a single-period interferometric lithography exposure pair; three-beam interferometric exposure pairs to form sparse arrays of sub-micrometer holes; five- and four-beam interferometric exposures to form a sparse array of sub-micrometer holes in a single exposure. Apparatuses disclosed include arrangements for the three-beam, five-beam and four-beam interferometric exposures.

A Molecular- and Nano-Electronics Test (MONET) platform fabricated using extreme ultraviolet lithography.

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

Dentinger, Paul M.; Cardinale, Gregory F.; Hunter, Luke L.

2003-12-01

We describe the fabrication and characterization of an electrode array test structure, designed for electrical probing of molecules and nanocrystals. We use Extreme Ultraviolet Lithography (EUVL) to define the electrical test platform features. As fabricated, the platform includes nominal electrode gaps of 0 nm, 40 nm, 60 nm, and 80 nm. Additional variation in electrode gap is achieved by controlling the exposure conditions, such as dose and focus. To enable EUVL based nanofabrication, we develop a novel bi-level photoresist process. The bi-level photoresist consists of a combination of a commercially available polydimethylglutarimide (PMGI) bottom layer and an experimental EUVL photoresistmore » top (imaging) layer. We measure the sensitivity of PMGI to EUV exposure dose as a function of photoresist pre-bake temperature, and using this data, optimize a metal lift-off process. Reliable fabrication of 700 Angstrom thick Au structures with sub-1000 Angstrom critical dimensions is achieved, even without the use of a Au adhesion layer, such as Ti. Several test platforms are used to characterize electrical properties of organic molecules deposited as self assembled monolayers.« less

Manufacturability of the X Architecture at the 90-nm technology node

NASA Astrophysics Data System (ADS)

Smayling, Michael C.; Sarma, Robin C.; Nagata, Toshiyuki; Arora, Narain; Duane, Michael P.; Oemardani, Shiany; Shah, Santosh

2004-05-01

In this paper, we discuss the results from a test chip that demonstrate the manufacturability and integration-worthiness of the X Architecture at the 90-nm technology node. We discuss how a collaborative effort between the design and chip making communities used the current generation of mask, lithography, wafer processing, inspection and metrology equipment to create 45 degree wires in typical metal pitches for the upper layers on a 90-nm device in a production environment. Cadence Design Systems created the test structure design and chip validation tools for the project. Canon"s KrF ES3 and ArF AS2 scanners were used for the lithography. Applied Materials used its interconnect fabrication technologies to produce the multilayer copper, low-k interconnect on 300-mm wafers. The results were confirmed for critical dimension and defect levels using Applied Materials" wafer inspection and metrology systems.

Monolithic microfabricated valves and pumps by multilayer soft lithography.

PubMed

Unger, M A; Chou, H P; Thorsen, T; Scherer, A; Quake, S R

2000-04-07

Soft lithography is an alternative to silicon-based micromachining that uses replica molding of nontraditional elastomeric materials to fabricate stamps and microfluidic channels. We describe here an extension to the soft lithography paradigm, multilayer soft lithography, with which devices consisting of multiple layers may be fabricated from soft materials. We used this technique to build active microfluidic systems containing on-off valves, switching valves, and pumps entirely out of elastomer. The softness of these materials allows the device areas to be reduced by more than two orders of magnitude compared with silicon-based devices. The other advantages of soft lithography, such as rapid prototyping, ease of fabrication, and biocompatibility, are retained.

Nanoimprint lithography for nanodevice fabrication

NASA Astrophysics Data System (ADS)

Barcelo, Steven; Li, Zhiyong

2016-09-01

Nanoimprint lithography (NIL) is a compelling technique for low cost nanoscale device fabrication. The precise and repeatable replication of nanoscale patterns from a single high resolution patterning step makes the NIL technique much more versatile than other expensive techniques such as e-beam or even helium ion beam lithography. Furthermore, the use of mechanical deformation during the NIL process enables grayscale lithography with only a single patterning step, not achievable with any other conventional lithography techniques. These strengths enable the fabrication of unique nanoscale devices by NIL for a variety of applications including optics, plasmonics and even biotechnology. Recent advances in throughput and yield in NIL processes demonstrate the potential of being adopted for mainstream semiconductor device fabrication as well.

Maskless Lithography and in situ Visualization of Conductivity of Graphene using Helium Ion Microscopy

DOE PAGES

Iberi, Vighter O.; Vlassiouk, Ivan V.; Zhang, X. -G.; ...

2015-07-07

The remarkable mechanical and electronic properties of graphene make it an ideal candidate for next generation nanoelectronics. With the recent development of commercial-level single-crystal graphene layers, the potential for manufacturing household graphene-based devices has improved, but significant challenges still remain with regards to patterning the graphene into devices. In the case of graphene supported on a substrate, traditional nanofabrication techniques such as e-beam lithography (EBL) are often used in fabricating graphene nanoribbons but the multi-step processes they require can result in contamination of the graphene with resists and solvents. In this letter, we report the utility of scanning helium ionmore » lithography for fabricating functional graphene nanoconductors that are supported directly on a silicon dioxide layer, and we measure the minimum feature size achievable due to limitations imposed by thermal fluctuations and ion scattering during the milling process. Further we demonstrate that ion beams, due to their positive charging nature, may be used to observe and test the conductivity of graphene-based nanoelectronic devices in situ.« less

Defect reduction of patterned media templates and disks

NASA Astrophysics Data System (ADS)

Luo, Kang; Ha, Steven; Fretwell, John; Ramos, Rick; Ye, Zhengmao; Schmid, Gerard; LaBrake, Dwayne; Resnick, Douglas J.; Sreenivasan, S. V.

2010-05-01

Imprint lithography has been shown to be an effective technique for the replication of nano-scale features. Acceptance of imprint lithography for manufacturing will require a demonstration of defect levels commensurate with cost-effective device production. This work summarizes the results of defect inspections of hard disks patterned using Jet and Flash Imprint Lithography (J-FILTM). Inspections were performed with optical based automated inspection tools. For the hard drive market, it is important to understand the defectivity of both the template and the imprinted disk. This work presents a methodology for automated pattern inspection and defect classification for imprint-patterned media. Candela CS20 and 6120 tools from KLA-Tencor map the optical properties of the disk surface, producing highresolution grayscale images of surface reflectivity and scattered light. Defects that have been identified in this manner are further characterized according to the morphology. The imprint process was tested after optimizing both the disk cleaning and adhesion layers processes that precede imprinting. An extended imprint run was performed and both the defect types and trends are reported.

National Synchrotron Light Source annual report 1991

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

Hulbert, S.L.; Lazarz, N.M.

1992-04-01

This report discusses the following research conducted at NSLS: atomic and molecular science; energy dispersive diffraction; lithography, microscopy and tomography; nuclear physics; UV photoemission and surface science; x-ray absorption spectroscopy; x-ray scattering and crystallography; x-ray topography; workshop on surface structure; workshop on electronic and chemical phenomena at surfaces; workshop on imaging; UV FEL machine reviews; VUV machine operations; VUV beamline operations; VUV storage ring parameters; x-ray machine operations; x-ray beamline operations; x-ray storage ring parameters; superconducting x-ray lithography source; SXLS storage ring parameters; the accelerator test facility; proposed UV-FEL user facility at the NSLS; global orbit feedback systems; and NSLSmore » computer system.« less

Progress in coherent lithography using table-top extreme ultraviolet lasers

NASA Astrophysics Data System (ADS)

Li, Wei

Nanotechnology has drawn a wide variety of attention as interesting phenomena occurs when the dimension of the structures is in the nanometer scale. The particular characteristics of nanoscale structures had enabled new applications in different fields in science and technology. Our capability to fabricate these nanostructures routinely for sure will impact the advancement of nanoscience. Apart from the high volume manufacturing in semiconductor industry, a small-scale but reliable nanofabrication tool can dramatically help the research in the field of nanotechnology. This dissertation describes alternative extreme ultraviolet (EUV) lithography techniques which combine table-top EUV laser and various cost-effective imaging strategies. For each technique, numerical simulations, system design, experiment result and its analysis will be presented. In chapter II, a brief review of the main characteristics of table-top EUV lasers will be addressed concentrating on its high power and large coherence radius that enable the lithography application described herein. The development of a Talbot EUV lithography system which is capable of printing 50nm half pitch nanopatterns will be illustrated in chapter III. A detailed discussion of its resolution limit will be presented followed by the development of X-Y-Z positioning stage, the fabrication protocol for diffractive EUV mask, and the pattern transfer using self- developed ion beam etching, and the dose control unit. In addition, this dissertation demonstrated the capability to fabricate functional periodic nanostructures using Talbot EUV lithography. After that, resolution enhancement techniques like multiple exposure, displacement Talbot EUV lithography, fractional Talbot EUV lithography, and Talbot lithography using 18.9nm amplified spontaneous emission laser will be demonstrated. Chapter IV will describe a hybrid EUV lithography which combines the Talbot imaging and interference lithography rendering a high resolution interference pattern whose lattice is modified by a custom designed Talbot mask. In other words, this method enables filling the arbitrary Talbot cell with ultra-fine interference nanofeatures. Detailed optics modeling, system design and experiment results using He-Ne laser and table top EUV laser are included. The last part of chapter IV will analyze its exclusive advantages over traditional Talbot or interference lithography.

Successful demonstration of a comprehensive lithography defect monitoring strategy

NASA Astrophysics Data System (ADS)

Peterson, Ingrid B.; Breaux, Louis H.; Cross, Andrew; von den Hoff, Michael

2003-07-01

This paper describes the validation of the methodology, the model and the impact of an optimized Lithography Defect Monitoring Strategy at two different semiconductor manufacturing factories. The lithography defect inspection optimization was implemented for the Gate Module at both factories running 0.13-0.15μm technologies on 200mm wafers, one running microprocessor and the other memory devices. As minimum dimensions and process windows decrease in the lithography area, new technologies and technological advances with resists and resist systems are being implemented to meet the demands. Along with these new technological advances in the lithography area comes potentially unforeseen defect issues. The latest lithography processes involve new resists in extremely thin, uniform films, exposing the films under conditions of highly optimized focus and illumination, and finally removing the resist completely and cleanly. The lithography cell is defined as the cluster of process equipment that accomplishes the coating process (surface prep, resist spin, edge-bead removal and soft bake), the alignment and exposure, and the developing process (post-exposure bake, develop, rinse) of the resist. Often the resist spinning process involves multiple materials such as BARC (bottom ARC) and / or TARC (top ARC) materials in addition to the resist itself. The introduction of these new materials with the multiple materials interfaces and the tightness of the process windows leads to an increased variety of defect mechanisms in the lithography area. Defect management in the lithography area has become critical to successful product introduction and yield ramp. The semiconductor process itself contributes the largest number and variety of defects, and a significant portion of the total defects originate within the lithography cell. From a defect management perspective, the lithography cell has some unique characteristics. First, defects in the lithography process module have the widest range of sizes, from full-wafer to suboptical, and with the largest variety of characteristics. Some of these defects fall into the categories of coating problems, focus and exposure defects, developer defects, edge-bead removal problems, contamination and scratches usually defined as lithography macro defects as shown in Figure 1. Others fall into the category of lithography micro defects, Figure 2. They are characterized as having low topography such as stains, developer spots, satellites, are very small such as micro-bridging, partial micro-bridging, micro-bubbles, CD variation and single isolated missing or deformed contacts or vias. Lithography is the only area of the fab besides CMP in which defect excursions can be corrected by reworking the wafers. The opportunity to fix defect problems without scrapping wafers is best served by a defect inspection strategy that captures the full range of all relevant defect types with a proper balance between the costs of monitoring and inspection and the potential cost of yield loss. In the previous paper [1] it was shown that a combination of macro inspection and high numerical aperture (NA) brightfield imaging inspection technology is best suited for the application in the case of the idealized fab modeled. In this paper we will report on the successful efforts in implementing and validating the lithography defect monitoring strategy at two existing 200 mm factories running 0.15 μm and 0.13 μm design rules.

High Throughput Optical Lithography by Scanning a Massive Array of Bowtie Aperture Antennas at Near-Field

DTIC Science & Technology

2015-11-03

scale optical projection system powered by spatial light modulators, such as digital micro-mirror device ( DMD ). Figure 4 shows the parallel lithography ...1Scientific RepoRts | 5:16192 | DOi: 10.1038/srep16192 www.nature.com/scientificreports High throughput optical lithography by scanning a massive...array of bowtie aperture antennas at near-field X. Wen1,2,3,*, A. Datta1,*, L. M. Traverso1, L. Pan1, X. Xu1 & E. E. Moon4 Optical lithography , the

Sub-100nm, Maskless Deep-UV Zone-Plate Array Lithography

DTIC Science & Technology

2004-05-07

The basic idea is to use fiducial grids, fabricated using interference lithography (or a derivative thereof) to determine the placement of features...sensed, and corrections are fed back to the beam-control electronics to cancel errors in the beam’s position. The virtue of interference lithography ...Sub-100nm, Maskless Deep-UV Zone-Plate Array Lithography Project Period: March 1, 2001 – February 28, 2004 F i n a l R e p o r t Army Research

Moore's law, lithography, and how optics drive the semiconductor industry

NASA Astrophysics Data System (ADS)

Hutcheson, G. Dan

2018-03-01

When the subject of Moore's Law arises, the important role that lithography plays and how advances in optics have made it all possible is seldom brought up in the world outside of lithography itself. When lithography is mentioned up in the value chain, it's often a critique of how advances are coming too slow and getting far too expensive. Yet advances in lithography are at the core of how Moore's Law is viable. This presentation lays out how technology and the economics of optics in manufacturing interleave to drive the immense value that semiconductors have brought to the world by making it smarter. Continuing these advances will be critical as electronics make the move from smart to cognitive.

Selective hydrophilic modification of Parylene C films: a new approach to cell micro-patterning for synthetic biology applications.

PubMed

Trantidou, T; Rao, C; Barrett, H; Camelliti, P; Pinto, K; Yacoub, M H; Athanasiou, T; Toumazou, C; Terracciano, C M; Prodromakis, T

2014-06-01

We demonstrate a simple, accurate and versatile method to manipulate Parylene C, a material widely known for its high biocompatibility, and transform it to a substrate that can effectively control the cellular microenvironment and consequently affect the morphology and function of the cells in vitro. The Parylene C scaffolds are fabricated by selectively increasing the material's surface water affinity through lithography and oxygen plasma treatment, providing free bonds for attachment of hydrophilic biomolecules. The micro-engineered constructs were tested as culture scaffolds for rat ventricular fibroblasts and neonatal myocytes (NRVM), toward modeling the unique anisotropic architecture of native cardiac tissue. The scaffolds induced the patterning of extracellular matrix compounds and therefore of the cells, which demonstrated substantial alignment compared to typical unstructured cultures. Ca(2+) cycling properties of the NRVM measured at rates of stimulation 0.5-2 Hz were significantly modified with a shorter time to peak and time to 90% decay, and a larger fluorescence amplitude (p < 0.001). The proposed technique is compatible with standard cell culturing protocols and exhibits long-term pattern durability. Moreover, it allows the integration of monitoring modalities into the micro-engineered substrates for a comprehensive interrogation of physiological parameters.

Lithography with MeV Energy Ions for Biomedical Applications: Accelerator Considerations

NASA Astrophysics Data System (ADS)

Sangyuenyongpipat, S.; Whitlow, H. J.; Nakagawa, S. T.; Yoshida, E.

2009-03-01

MeV ion beam lithographies are very powerful techniques for 3D direct writing in positive or negtive photoresist materials. Nanometer-scale rough structures, or clear areas with straight vertical sidewalls as thin as a few 10's of nm in a resist of a few nm to 100 μm thickness can be made. These capabilities are particularly useful for lithography in cellular- and sub-cellular level biomedical research and technology applications. It can be used for tailor making special structures such as optical waveguides, biosensors, DNA sorters, spotting plates, systems for DNA, protein and cell separation, special cell-growth substrates and microfluidic lab-on-a-chip devices. Furthermore MeV ion beam lithography can be used for rapid prototyping, and also making master stamps and moulds for mass production by hot embossing and nanoimprint lithography. The accelerator requirements for three different high energy ion beam lithography techniques are overviewed. We consider the special requirements placed on the accelerator and how this is achieved for a commercial proton beam writing tool.

Micro-fabrication method of graphite mesa microdevices based on optical lithography technology

NASA Astrophysics Data System (ADS)

Zhang, Cheng; Wen, Donghui; Zhu, Huamin; Zhang, Xiaorui; Yang, Xing; Shi, Yunsheng; Zheng, Tianxiang

2017-12-01

Graphite mesa microdevices have incommensurate contact nanometer interfaces, superlubricity, high-speed self-retraction, and other characteristics, which have potential applications in high-performance oscillators and micro-scale switches, memory devices, and gyroscopes. However, the current method of fabricating graphite mesa microdevices is mainly based on high-cost, low efficiency electron beam lithography technology. In this paper, the processing technologies of graphite mesa microdevices with various shapes and sizes were investigated by a low-cost micro-fabrication method, which was mainly based on optical lithography technology. The characterization results showed that the optical lithography technology could realize a large-area of patterning on the graphite surface, and the graphite mesa microdevices, which have a regular shape, neat arrangement, and high verticality could be fabricated in large batches through optical lithography technology. The experiments and analyses showed that the graphite mesa microdevices fabricated through optical lithography technology basically have the same self-retracting characteristics as those fabricated through electron beam lithography technology, and the maximum size of the graphite mesa microdevices with self-retracting phenomenon can reach 10 µm  ×  10 µm. Therefore, the proposed method of this paper can realize the high-efficiency and low-cost processing of graphite mesa microdevices, which is significant for batch fabrication and application of graphite mesa microdevices.

Fabrication process for a gradient index x-ray lens

DOEpatents

Bionta, R.M.; Makowiecki, D.M.; Skulina, K.M.

1995-01-17

A process is disclosed for fabricating high efficiency x-ray lenses that operate in the 0.5-4.0 keV region suitable for use in biological imaging, surface science, and x-ray lithography of integrated circuits. The gradient index x-ray optics fabrication process broadly involves co-sputtering multi-layers of film on a wire, followed by slicing and mounting on block, and then ion beam thinning to a thickness determined by periodic testing for efficiency. The process enables the fabrication of transmissive gradient index x-ray optics for the 0.5-4.0 keV energy range. This process allows the fabrication of optical elements for the next generation of imaging and x-ray lithography instruments in the soft x-ray region. 13 figures.

National Synchrotron Light Source annual report 1991. Volume 1, October 1, 1990--September 30, 1991

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

Hulbert, S.L.; Lazarz, N.M.

1992-04-01

This report discusses the following research conducted at NSLS: atomic and molecular science; energy dispersive diffraction; lithography, microscopy and tomography; nuclear physics; UV photoemission and surface science; x-ray absorption spectroscopy; x-ray scattering and crystallography; x-ray topography; workshop on surface structure; workshop on electronic and chemical phenomena at surfaces; workshop on imaging; UV FEL machine reviews; VUV machine operations; VUV beamline operations; VUV storage ring parameters; x-ray machine operations; x-ray beamline operations; x-ray storage ring parameters; superconducting x-ray lithography source; SXLS storage ring parameters; the accelerator test facility; proposed UV-FEL user facility at the NSLS; global orbit feedback systems; and NSLSmore » computer system.« less

Science & Technology Review September/October 2008

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

Bearinger, J P

2008-07-21

This issue has the following articles: (1) Answering Scientists Most Audacious Questions--Commentary by Dona Crawford; (2) Testing the Accuracy of the Supernova Yardstick--High-resolution simulations are advancing understanding of Type Ia supernovae to help uncover the mysteries of dark energy; (3) Developing New Drugs and Personalized Medical Treatment--Accelerator mass spectrometry is emerging as an essential tool for assessing the effects of drugs in humans; (4) Triage in a Patch--A painless skin patch and accompanying detector can quickly indicate human exposure to biological pathogens, chemicals, explosives, or radiation; and (5) Smoothing Out Defects for Extreme Ultraviolet Lithography--A process for smoothing mask defectsmore » helps move extreme ultraviolet lithography one step closer to creating smaller, more powerful computer chips.« less

Fabrication process for a gradient index x-ray lens

DOEpatents

Bionta, Richard M.; Makowiecki, Daniel M.; Skulina, Kenneth M.

1995-01-01

A process for fabricating high efficiency x-ray lenses that operate in the 0.5-4.0 keV region suitable for use in biological imaging, surface science, and x-ray lithography of integrated circuits. The gradient index x-ray optics fabrication process broadly involves co-sputtering multi-layers of film on a wire, followed by slicing and mounting on block, and then ion beam thinning to a thickness determined by periodic testing for efficiency. The process enables the fabrication of transmissive gradient index x-ray optics for the 0.5-4.0 keV energy range. This process allows the fabrication of optical elements for the next generation of imaging and x-ray lithography instruments m the soft x-ray region.

An investigation on defect-generation conditions in immersion lithography

NASA Astrophysics Data System (ADS)

Tomita, Tadatoshi; Shimoaoki, Takeshi; Enomoto, Masashi; Kyoda, Hideharu; Kitano, Junichi; Suganaga, Toshifumi

2006-03-01

As a powerful candidate for a lithography technique that can accommodate the scaling-down of semiconductors, 193-nm immersion lithography-which realizes a high numerical aperture (NA) and uses deionized water as the medium between the lens and wafer in the exposure system-has been developing at a rapid pace and has reached the stage of practical application. In regards to defects that are a cause for concern in the case of 193-nm immersion lithography, however, many components are still unclear and many problems remain to be solved. It has been pointed out, for example, that in the case of 193-nm immersion lithography, immersion of the resist film in deionized water during exposure causes infiltration of moisture into the resist film, internal components of the resist dissolve into the deionized water, and residual water generated during exposure affects post-processing. Moreover, to prevent this influence of directly immersing the resist in de-ionized water, application of a protective film is regarded as effective. However, even if such a film is applied, it is still highly likely that the above-mentioned defects will still occur. Accordingly, to reduce these defects, it is essential to identify the typical defects occurring in 193-nm immersion lithography and to understand the condition for generation of defects by using some kinds of protective films and resist materials. Furthermore, from now onwards, with further scaling down of semiconductors, it is important to maintain a clear understanding of the relation between defect-generation conditions and critical dimensions (CD). Aiming to extract typical defects occurring in 193-nm immersion lithography, the authors carried out a comparative study with dry exposure lithography, thereby confirming several typical defects associated with immersion lithography. We then investigated the conditions for generation of defects in the case of some kinds of protective films. In addition to that, by investigating the defect-generation conditions and comparing the classification data between wet and dry exposure, we were able to determine the origin of each particular defect involved in immersion lithography. Furthermore, the comparison of CD for wet and dry processing could indicate the future defectivity levels to be expected with shrinking immersion process critical dimensions.

Lossless compression techniques for maskless lithography data

NASA Astrophysics Data System (ADS)

Dai, Vito; Zakhor, Avideh

2002-07-01

Future lithography systems must produce more dense chips with smaller feature sizes, while maintaining the throughput of one wafer per sixty seconds per layer achieved by today's optical lithography systems. To achieve this throughput with a direct-write maskless lithography system, using 25 nm pixels for 50 nm feature sizes, requires data rates of about 10 Tb/s. In a previous paper, we presented an architecture which achieves this data rate contingent on consistent 25 to 1 compression of lithography data, and on implementation of a decoder-writer chip with a real-time decompressor fabricated on the same chip as the massively parallel array of lithography writers. In this paper, we examine the compression efficiency of a spectrum of techniques suitable for lithography data, including two industry standards JBIG and JPEG-LS, a wavelet based technique SPIHT, general file compression techniques ZIP and BZIP2, our own 2D-LZ technique, and a simple list-of-rectangles representation RECT. Layouts rasterized both to black-and-white pixels, and to 32 level gray pixels are considered. Based on compression efficiency, JBIG, ZIP, 2D-LZ, and BZIP2 are found to be strong candidates for application to maskless lithography data, in many cases far exceeding the required compression ratio of 25. To demonstrate the feasibility of implementing the decoder-writer chip, we consider the design of a hardware decoder based on ZIP, the simplest of the four candidate techniques. The basic algorithm behind ZIP compression is Lempel-Ziv 1977 (LZ77), and the design parameters of LZ77 decompression are optimized to minimize circuit usage while maintaining compression efficiency.

Scanning digital lithography providing high speed large area patterning with diffraction limited sub-micron resolution

NASA Astrophysics Data System (ADS)

Wen, Sy-Bor; Bhaskar, Arun; Zhang, Hongjie

2018-07-01

A scanning digital lithography system using computer controlled digital spatial light modulator, spatial filter, infinity correct optical microscope and high precision translation stage is proposed and examined. Through utilizing the spatial filter to limit orders of diffraction modes for light delivered from the spatial light modulator, we are able to achieve diffraction limited deep submicron spatial resolution with the scanning digital lithography system by using standard one inch level optical components with reasonable prices. Raster scanning of this scanning digital lithography system using a high speed high precision x-y translation stage and piezo mount to real time adjust the focal position of objective lens allows us to achieve large area sub-micron resolved patterning with high speed (compared with e-beam lithography). It is determined in this study that to achieve high quality stitching of lithography patterns with raster scanning, a high-resolution rotation stage will be required to ensure the x and y directions of the projected pattern are in the same x and y translation directions of the nanometer precision x-y translation stage.

Advanced electric-field scanning probe lithography on molecular resist using active cantilever

NASA Astrophysics Data System (ADS)

Kaestner, Marcus; Aydogan, Cemal; Lipowicz, Hubert-Seweryn; Ivanov, Tzvetan; Lenk, Steve; Ahmad, Ahmad; Angelov, Tihomir; Reum, Alexander; Ishchuk, Valentyn; Atanasov, Ivaylo; Krivoshapkina, Yana; Hofer, Manuel; Holz, Mathias; Rangelow, Ivo W.

2015-03-01

The routine "on demand" fabrication of features smaller than 10 nm opens up new possibilities for the realization of many novel nanoelectronic, NEMS, optical and bio-nanotechnology-based devices. Based on the thermally actuated, piezoresistive cantilever technology we have developed a first prototype of a scanning probe lithography (SPL) platform able to image, inspect, align and pattern features down to single digit nano regime. The direct, mask-less patterning of molecular resists using active scanning probes represents a promising path circumventing the problems in today's radiation-based lithography. Here, we present examples of practical applications of the previously published electric field based, current-controlled scanning probe lithography on molecular glass resist calixarene by using the developed tabletop SPL system. We demonstrate the application of a step-and-repeat scanning probe lithography scheme including optical as well as AFM based alignment and navigation. In addition, sequential read-write cycle patterning combining positive and negative tone lithography is shown. We are presenting patterning over larger areas (80 x 80 μm) and feature the practical applicability of the lithographic processes.

Large-area soft x-ray projection lithography using multilayer mirrors structured by RIE

NASA Astrophysics Data System (ADS)

Rahn, Steffen; Kloidt, Andreas; Kleineberg, Ulf; Schmiedeskamp, Bernt; Kadel, Klaus; Schomburg, Werner K.; Hormes, F. J.; Heinzmann, Ulrich

1993-01-01

SXPL (soft X-ray projection lithography) is one of the most promising applications of X-ray reflecting optics using multilayer mirrors. Within our collaboration, such multilayer mirrors were fabricated, characterized, laterally structured and then used as reflection masks in a projecting lithography procedure. Mo/Si-multilayer mirrors were produced by electron beam evaporation in UHV under thermal treatment with an in-situ X-ray controlled thickness in the region of 2d equals 14 nm. The reflectivities measured at normal incidence reached up to 54%. Various surface analysis techniques have been applied in order to characterize and optimize the X-ray mirrors. The multilayers were patterned by reactive ion etching (RIE) with CF(subscript 4), using a photoresist as the etch mask, thus producing X-ray reflection masks. The masks were tested in the synchrotron radiation laboratory of the electron accelerator ELSA at the Physikalisches Institut of Bonn University. A double crystal X-ray monochromator was modified so as to allow about 0.5 cm(superscript 2) of the reflection mask to be illuminated by white synchrotron radiation. The reflected patterns were projected (with an energy of 100 eV) onto the resist (Hoechst AZ PF 514), which was mounted at an average distance of about 7 mm. In the first test-experiments, structure sizes down to 8 micrometers were nicely reproduced over the whole of the exposed area. Smaller structures were distorted by Fresnel-diffraction. The theoretically calculated diffraction images agree very well with the observed images.

Fabrication of biomimetic dry-adhesion structures through nanosphere lithography

NASA Astrophysics Data System (ADS)

Kuo, P. C.; Chang, N. W.; Suen, Y.; Yang, S. Y.

2018-03-01

Components with surface nanostructures suitable for biomimetic dry adhesion have a great potential in applications such as gecko tape, climbing robots, and skin patches. In this study, a nanosphere lithography technique with self-assembly nanospheres was developed to achieve effective and efficient fabrication of dry-adhesion structures. Self-assembled monolayer nanospheres with high regularity were obtained through tilted dip-coating. Reactive-ion etching of the self-assembled nanospheres was used to fabricate nanostructures of different shapes and aspect ratios by varying the etching time. Thereafter, nickel molds with inverse nanostructures were replicated using the electroforming process. Polydimethylsiloxane (PDMS) nanostructures were fabricated through a gas-assisted hot-embossing method. The pulling test was performed to measure the shear adhesion on the glass substrate of a sample, and the static contact angle was measured to verify the hydrophobic property of the structure. The enhancement of the structure indicates that the adhesion force increased from 1.2 to 4.05 N/cm2 and the contact angle increased from 118.6° to 135.2°. This columnar structure can effectively enhance the adhesion ability of PDMS, demonstrating the potential of using nanosphere lithography for the fabrication of adhesive structures.

Revisiting adoption of high transmission PSM: pros, cons and path forward

NASA Astrophysics Data System (ADS)

Ma, Z. Mark; McDonald, Steve; Progler, Chris

2009-12-01

High transmission attenuated phase shift masks (Hi-T PSM) have been successfully applied in volume manufacturing for certain memory devices. Moreover, numerous studies have shown the potential benefits of Hi-T PSM for specific lithography applications. In this paper, the potential for extending Hi-T PSM to logic devices, is revisited with an emphasis on understanding layout, transmission, and manufacturing of Hi-T PSM versus traditional 6% embedded attenuated phase shift mask (EAPSM). Simulations on various layouts show Hi-T PSM has advantage over EAPSM in low duty cycle line patterns and high duty cycle space patterns. The overall process window can be enhanced when Hi- T PSM is combined with optimized optical proximity correction (OPC), sub-resolution assist features (SRAF), and source illumination. Therefore, Hi-T PSM may be a viable and lower cost alternative to other complex resolution enhancement technology (RET) approaches. Aerial image measurement system (AIMS) results on test masks, based on an inverse lithography technology (ILT) generated layout, confirm the simulation results. New advancement in high transmission blanks also make low topography Hi-T PSM a reality, which can minimize scattering effects in high NA lithography.

Hotspot detection using image pattern recognition based on higher-order local auto-correlation

NASA Astrophysics Data System (ADS)

Maeda, Shimon; Matsunawa, Tetsuaki; Ogawa, Ryuji; Ichikawa, Hirotaka; Takahata, Kazuhiro; Miyairi, Masahiro; Kotani, Toshiya; Nojima, Shigeki; Tanaka, Satoshi; Nakagawa, Kei; Saito, Tamaki; Mimotogi, Shoji; Inoue, Soichi; Nosato, Hirokazu; Sakanashi, Hidenori; Kobayashi, Takumi; Murakawa, Masahiro; Higuchi, Tetsuya; Takahashi, Eiichi; Otsu, Nobuyuki

2011-04-01

Below 40nm design node, systematic variation due to lithography must be taken into consideration during the early stage of design. So far, litho-aware design using lithography simulation models has been widely applied to assure that designs are printed on silicon without any error. However, the lithography simulation approach is very time consuming, and under time-to-market pressure, repetitive redesign by this approach may result in the missing of the market window. This paper proposes a fast hotspot detection support method by flexible and intelligent vision system image pattern recognition based on Higher-Order Local Autocorrelation. Our method learns the geometrical properties of the given design data without any defects as normal patterns, and automatically detects the design patterns with hotspots from the test data as abnormal patterns. The Higher-Order Local Autocorrelation method can extract features from the graphic image of design pattern, and computational cost of the extraction is constant regardless of the number of design pattern polygons. This approach can reduce turnaround time (TAT) dramatically only on 1CPU, compared with the conventional simulation-based approach, and by distributed processing, this has proven to deliver linear scalability with each additional CPU.

Fabrication of nanochannels on polyimide films using dynamic plowing lithography

NASA Astrophysics Data System (ADS)

Stoica, Iuliana; Barzic, Andreea Irina; Hulubei, Camelia

2017-12-01

Three distinct polyimide films were analyzed from the point of view of their morphology in order to determine if their surface features can be adapted for applications where surface anisotropy is mandatory. Channels of nanometric dimensions were created on surface of the specimens by using a less common atomic force microscopy (AFM) method, namely Dynamic Plowing Lithography (DPL). The changes generated by DPL procedure were monitored through the surface texture and other functional parameters, denoting the surface orientation degree and also bearing and fluid retention properties. The results revealed that in the same nanolithography conditions, the diamine and dianhydride moieties have affected the characteristics of the nanochannels. This was explained based on the aliphatic/aromatic nature of the monomers and the backbone flexibility. The reported data are of great importance in designing custom nanostructures with enhanced anisotropy on surface of polyimide films for liquid crystal orientation or guided cell growth purposes. At the end, to track the effect of the nanolithography process on the tip sharpness, degradation and contamination, the blind tip reconstruction was performed on AFM probe, before and after lithography experiments, using TGT1 test grating AFM image.

High resolution imaging and lithography with hard x rays using parabolic compound refractive lenses

NASA Astrophysics Data System (ADS)

Schroer, C. G.; Benner, B.; Günzler, T. F.; Kuhlmann, M.; Zimprich, C.; Lengeler, B.; Rau, C.; Weitkamp, T.; Snigirev, A.; Snigireva, I.; Appenzeller, J.

2002-03-01

Parabolic compound refractive lenses are high quality optical components for hard x rays. They are particularly suited for full field imaging, with applications in microscopy and x-ray lithography. Taking advantage of the large penetration depth of hard x rays, the interior of opaque samples can be imaged with submicrometer resolution. To obtain the three-dimensional structure of a sample, microscopy is combined with tomographic techniques. In a first hard x-ray lithography experiment, parabolic compound refractive lenses have been used to project the reduced image of a lithography mask onto a resist. Future developments are discussed.

Nanoparticle photoresist studies for EUV lithography

NASA Astrophysics Data System (ADS)

Kasahara, Kazuki; Xu, Hong; Kosma, Vasiliki; Odent, Jeremy; Giannelis, Emmanuel P.; Ober, Christopher K.

2017-03-01

EUV (extreme ultraviolet) lithography is one of the most promising candidates for next generation lithography. The main challenge for EUV resists is to simultaneously satisfy resolution, LWR (line-width roughness) and sensitivity requirements according to the ITRS roadmap. Though polymer type CAR (chemically amplified resist) is the currently standard photoresist, entirely new resist platforms are required due to the performance targets of smaller process nodes. In this paper, recent progress in nanoparticle photoresists which Cornell University has intensely studied is discussed. Lithography performance, especially scum elimination, improvement studies with the dissolution rate acceleration concept and new metal core applications are described.

Design and fabrication of nano-imprint templates using unique pattern transforms and primitives

NASA Astrophysics Data System (ADS)

MacDonald, Susan; Mellenthin, David; Rentzsch, Kevin; Kramer, Kenneth; Ellenson, James; Hostetler, Tim; Enck, Ron

2005-11-01

Increasing numbers of MEMS, photonic, and integrated circuit manufacturers are investigating the use of Nano-imprint Lithography or Step and Flash Imprint Lithography (SFIL) as a lithography choice for making various devices and products. Their main interests in using these technologies are the lack of aberrations inherent in traditional optical reduction lithography, and the relative low cost of imprint tools. Since imprint templates are at 1X scale, the small sizes of these structures have necessitated the use of high-resolution 50KeV, and 100KeV e-beam lithography tools to build these templates. For MEMS and photonic applications, the structures desired are often circles, arches, and other non-orthogonal shapes. It has long been known that both 50keV, and especially 100keV e-beam lithography tools are extremely accurate, and can produce very high resolution structures, but the trade off is long write times. The main drivers in write time are shot count and stage travel. This work will show how circles and other non-orthogonal shapes can be produced with a 50KeV Variable Shaped Beam (VSB) e-beam lithography system using unique pattern transforms and primitive shapes, while keeping the shot count and write times under control. The quality of shapes replicated into the resist on wafer using an SFIL tool will also be presented.

Microsystems Research in Japan

DTIC Science & Technology

2003-09-01

microsystems applications, like microfluidic systems, will require more than planar lithography -based fabrication processes. The committee was impressed by the...United States focused on exploiting silicon planar lithography as the core technology for microstructure fabrication, whereas Japan explored a wide...including LIGA and its extensions, micro-stereolithography, and e-beam lithography . The range of materials seen in Japan was broader than in the

Shear Stress Sensing using Elastomer Micropillar Arrays

NASA Technical Reports Server (NTRS)

Wohl, Christopher J.; Palmieri, Frank L.; Lin, Yi; Jackson, Allen M.; Cissoto, Alexxandra; Sheplak, Mark; Connell, John W.

2013-01-01

The measurement of shear stress developed as a fluid moves around a solid body is difficult to measure. Stresses at the fluid-solid interface are very small and the nature of the fluid flow is easily disturbed by introducing sensor components to the interface. To address these challenges, an array of direct and indirect techniques have been investigated with various advantages and challenges. Hot wire sensors and other indirect sensors all protrude significantly into the fluid flow. Microelectromechanical systems (MEMS) devices, although facilitating very accurate measurements, are not durable, are prone to contamination, and are difficult to implement into existing model geometries. One promising approach is the use of engineered surfaces that interact with fluid flow in a detectable manner. To this end, standard lithographic techniques have been utilized to generate elastomeric micropillar arrays of various lengths and diameters. Micropillars of controlled length and width were generated in polydimethylsiloxane (PDMS) elastomer using a soft-lithography technique. The 3D mold for micropillar replication was fabricated using laser ablative micromachining and contact lithography. Micropillar dimensions and mechanical properties were characterized and compared to shear sensing requirements. The results of this characterization as well as shear stress detection techniques will be discussed.

Laser microprocessing and nanoengineering of large-area functional micro/nanostructures

NASA Astrophysics Data System (ADS)

Tang, M.; Xie, X. Z.; Yang, J.; Chen, Z. C.; Xu, L.; Choo, Y. S.; Hong, M. H.

2011-12-01

Laser microprocessing and nanoengineering are of great interest to both scientists and engineers, since the inspired properties of functional micro/nanostructures over large areas can lead to numerous unique applications. Currently laser processing systems combined with high speed automation ensure the focused laser beam to process various materials at a high throughput and a high accuracy over large working areas. UV lasers are widely used in both laser microprocessing and nanoengineering. However by improving the processing methods, green pulsed laser is capable of replacing UV lasers to make high aspect ratio micro-grooves on fragile and transparent sapphire substrates. Laser micro-texturing can also tune the wetting property of metal surfaces from hydrophilic to super-hydrophobic at a contact angle of 161° without chemical coating. Laser microlens array (MLA) can split a laser beam into multiple laser beams and reduce the laser spot size down to sub-microns. It can be applied to fabricate split ring resonator (SRR) meta-materials for THz sensing, surface plasmonic resonance (SPR) structures for NIR and molding tools for soft lithography. Furthermore, laser interference lithography combined with thermal annealing can obtain a large area of sub-50nm nano-dot clusters used for SPR applications.

Hurdles in low k1 mass production

NASA Astrophysics Data System (ADS)

Yim, Donggyu; Yang, Hyunjo; Park, Chanha; Hong, Jongkyun; Choi, Jaeseung

2005-05-01

As the optical lithography pushes toward its theoretical resolution limit 0.25k1, the application of aggressive Resolution Enhancement Techniques (RETs) are required in order to ensure necessary resolution, sufficient process window, and reasonable MEEF in critical layers. When chip makers are adopting RETs in low k1 device, there are a lot of crucial factors to take into account in the development and mass production. Those hurdles are not only difficult to overcome but also highly risky to the company, which adopts low k1 mass production strategy. But, low k1 production strategy is very attractive to all chip makers, owing to improving production capacity and cost of ownership. So, low k1 technology has been investigated by many lithography engineers. Lots of materials have been introduced. Most of them are just in RnD level. In this study, low k1 mass production issues shall be introduced, mainly. The definition of low k1 in mass production shall be suggested. And, a lot of low_k1 issues shall be introduced, also. Most of them were investigated/experienced in RnD development stage and final mass production line. Low k1 mass production, is some what different from only RnD development.

Tunnel barrier design in donor nanostructures defined by hydrogen-resist lithography

NASA Astrophysics Data System (ADS)

Pascher, Nikola; Hennel, Szymon; Mueller, Susanne; Fuhrer, Andreas

2016-08-01

A four-terminal donor quantum dot (QD) is used to characterize potential barriers between degenerately doped nanoscale contacts. The QD is fabricated by hydrogen-resist lithography on Si(001) in combination with n-type doping by phosphine. The four contacts have different separations (d = 9, 12, 16 and 29 nm) to the central 6 nm × 6 nm QD island, leading to different tunnel and capacitive coupling. Cryogenic transport measurements in the Coulomb-blockade (CB) regime are used to characterize these tunnel barriers. We find that field enhancement near the apex of narrow dopant leads is an important effect that influences both barrier breakdown and the magnitude of the tunnel current in the CB transport regime. From CB-spectroscopy measurements, we extract the mutual capacitances between the QD and the four contacts, which scale inversely with the contact separation d. The capacitances are in excellent agreement with numerical values calculated from the pattern geometry in the hydrogen resist. Furthermore, we show that by engineering the source-drain tunnel barriers to be asymmetric, we obtain a much simpler excited-state spectrum of the QD, which can be directly linked to the orbital single-particle spectrum.

Tilted pillar array fabrication by the combination of proton beam writing and soft lithography for microfluidic cell capture: Part 1 Design and feasibility.

PubMed

Rajta, Istvan; Huszánk, Robert; Szabó, Atilla T T; Nagy, Gyula U L; Szilasi, Szabolcs; Fürjes, Peter; Holczer, Eszter; Fekete, Zoltan; Járvás, Gabor; Szigeti, Marton; Hajba, Laszlo; Bodnár, Judit; Guttman, Andras

2016-02-01

Design, fabrication, integration, and feasibility test results of a novel microfluidic cell capture device is presented, exploiting the advantages of proton beam writing to make lithographic irradiations under multiple target tilting angles and UV lithography to easily reproduce large area structures. A cell capture device is demonstrated with a unique doubly tilted micropillar array design for cell manipulation in microfluidic applications. Tilting the pillars increased their functional surface, therefore, enhanced fluidic interaction when special bioaffinity coating was used, and improved fluid dynamic behavior regarding cell culture injection. The proposed microstructures were capable to support adequate distribution of body fluids, such as blood, spinal fluid, etc., between the inlet and outlet of the microfluidic sample reservoirs, offering advanced cell capture capability on the functionalized surfaces. The hydrodynamic characteristics of the microfluidic systems were tested with yeast cells (similar size as red blood cells) for efficient capture. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

X ray reflection masks: Manufacturing, characterization and first tests

NASA Astrophysics Data System (ADS)

Rahn, Stephen

1992-09-01

SXPL (Soft X-ray Projection Lithography) multilayer mirrors are characterized, laterally structured and then used as reflection masks in a projecting lithography procedure. Mo/Si-multilayer mirrors with a 2d in the region of 14 nm were characterized by Cu-k(alpha) grazing incidence as well as soft X-ray normal incidence reflectivity measurements. The multilayer mirrors were patterned by reactive ion etching with CF4 using a photoresist as etch mask, thus producing X-ray reflection masks. The masks were tested at the synchrotron radiation laboratory of the electron accelerator ELSA. A double crystal X-ray monochromator was modified so as to allow about 0.5 sq cm of the reflection mask to be illuminated by white synchrotron radiation. The reflected patterns were projected (with an energy of 100 eV) onto a resist and structure sizes down to 8 micrometers were nicely reproduced. Smaller structures were distorted by Fresnel-diffraction. The theoretically calculated diffraction images agree very well with the observed images.

Low thermal distortion extreme-UV lithography reticle

DOEpatents

Gianoulakis, Steven E.; Ray-Chaudhuri, Avijit K.

2002-01-01

Thermal distortion of reticles or masks can be significantly reduced by emissivity engineering, i.e., the selective placement or omission of coatings on the reticle. Reflective reticles so fabricated exhibit enhanced heat transfer thereby reducing the level of thermal distortion and ultimately improving the quality of the transcription of the reticle pattern onto the wafer. Reflective reticles include a substrate having an active region that defines the mask pattern and non-active region(s) that are characterized by a surface that has a higher emissivity than that of the active region. The non-active regions are not coated with the radiation reflective material.

Low thermal distortion extreme-UV lithography reticle

DOEpatents

Gianoulakis, Steven E.; Ray-Chaudhuri, Avijit K.

2001-01-01

Thermal distortion of reticles or masks can be significantly reduced by emissivity engineering, i.e., the selective placement or omission of coatings on the reticle. Reflective reticles so fabricated exhibit enhanced heat transfer thereby reducing the level of thermal distortion and ultimately improving the quality of the transcription of the reticle pattern onto the wafer. Reflective reticles include a substrate having an active region that defines the mask pattern and non-active region(s) that are characterized by a surface that has a higher emissivity than that of the active region. The non-active regions are not coated with the radiation reflective material.

Simulation of the effect of incline incident angle in DMD Maskless Lithography

NASA Astrophysics Data System (ADS)

Liang, L. W.; Zhou, J. Y.; Xiang, L. L.; Wang, B.; Wen, K. H.; Lei, L.

2017-06-01

The aim of this study is to provide a simulation method for investigation of the intensity fluctuation caused by the inclined incident angle in DMD (digital micromirror device) maskless lithography. The simulation consists of eight main processes involving the simplification of the DMD aperture function and light propagation utilizing the non-parallel angular spectrum method. These processes provide a possibility of co-simulation in the spatial frequency domain, which combines the microlens array and DMD in the maskless lithography system. The simulation provided the spot shape and illumination distribution. These two parameters are crucial in determining the exposure dose in the existing maskless lithography system.

Range pattern matching with layer operations and continuous refinements

NASA Astrophysics Data System (ADS)

Tseng, I.-Lun; Lee, Zhao Chuan; Li, Yongfu; Perez, Valerio; Tripathi, Vikas; Ong, Jonathan Yoong Seang

2018-03-01

At advanced and mainstream process nodes (e.g., 7nm, 14nm, 22nm, and 55nm process nodes), lithography hotspots can exist in layouts of integrated circuits even if the layouts pass design rule checking (DRC). Existence of lithography hotspots in a layout can cause manufacturability issues, which can result in yield losses of manufactured integrated circuits. In order to detect lithography hotspots existing in physical layouts, pattern matching (PM) algorithms and commercial PM tools have been developed. However, there are still needs to use DRC tools to perform PM operations. In this paper, we propose a PM synthesis methodology, which uses a continuous refinement technique, for the automatic synthesis of a given lithography hotspot pattern into a DRC deck, which consists of layer operation commands, so that an equivalent PM operation can be performed by executing the synthesized deck with the use of a DRC tool. Note that the proposed methodology can deal with not only exact patterns, but also range patterns. Also, lithography hotspot patterns containing multiple layers can be processed. Experimental results show that the proposed methodology can accurately and efficiently detect lithography hotspots in physical layouts.

Intelligent control system based on ARM for lithography tool

NASA Astrophysics Data System (ADS)

Chen, Changlong; Tang, Xiaoping; Hu, Song; Wang, Nan

2014-08-01

The control system of traditional lithography tool is based on PC and MCU. The PC handles the complex algorithm, human-computer interaction, and communicates with MCU via serial port; The MCU controls motors and electromagnetic valves, etc. This mode has shortcomings like big volume, high power consumption, and wasting of PC resource. In this paper, an embedded intelligent control system of lithography tool, based on ARM, is provided. The control system used S5PV210 as processor, completing the functions of PC in traditional lithography tool, and provided a good human-computer interaction by using LCD and capacitive touch screen. Using Android4.0.3 as operating system, the equipment provided a cool and easy UI which made the control more user-friendly, and implemented remote control and debug, pushing video information of product by network programming. As a result, it's convenient for equipment vendor to provide technical support for users. Finally, compared with traditional lithography tool, this design reduced the PC part, making the hardware resources efficiently used and reducing the cost and volume. Introducing embedded OS and the concepts in "The Internet of things" into the design of lithography tool can be a development trend.

Vectorial mask optimization methods for robust optical lithography

NASA Astrophysics Data System (ADS)

Ma, Xu; Li, Yanqiu; Guo, Xuejia; Dong, Lisong; Arce, Gonzalo R.

2012-10-01

Continuous shrinkage of critical dimension in an integrated circuit impels the development of resolution enhancement techniques for low k1 lithography. Recently, several pixelated optical proximity correction (OPC) and phase-shifting mask (PSM) approaches were developed under scalar imaging models to account for the process variations. However, the lithography systems with larger-NA (NA>0.6) are predominant for current technology nodes, rendering the scalar models inadequate to describe the vector nature of the electromagnetic field that propagates through the optical lithography system. In addition, OPC and PSM algorithms based on scalar models can compensate for wavefront aberrations, but are incapable of mitigating polarization aberrations in practical lithography systems, which can only be dealt with under the vector model. To this end, we focus on developing robust pixelated gradient-based OPC and PSM optimization algorithms aimed at canceling defocus, dose variation, wavefront and polarization aberrations under a vector model. First, an integrative and analytic vector imaging model is applied to formulate the optimization problem, where the effects of process variations are explicitly incorporated in the optimization framework. A steepest descent algorithm is then used to iteratively optimize the mask patterns. Simulations show that the proposed algorithms can effectively improve the process windows of the optical lithography systems.

Holographic lithography for biomedical applications

NASA Astrophysics Data System (ADS)

Stankevicius, E.; Balciunas, E.; Malinauskas, M.; Raciukaitis, G.; Baltriukiene, D.; Bukelskiene, V.

2012-06-01

Fabrication of scaffolds for cell growth with appropriate mechanical characteristics is top-most important for successful creation of tissue. Due to ability of fast fabrication of periodic structures with a different period, the holographic lithography technique is a suitable tool for scaffolds fabrication. The scaffolds fabricated by holographic lithography can be used in various biomedical investigations such as the cellular adhesion, proliferation and viability. These investigations allow selection of the suitable material and geometry of scaffolds which can be used in creation of tissue. Scaffolds fabricated from di-acrylated poly(ethylene glycol) (PEG-DA-258) over a large area by holographic lithography technique are presented in this paper. The PEG-DA scaffolds fabricated by holographic lithography showed good cytocompatibility for rabbit myogenic stem cells. It was observed that adult rabbit muscle-derived myogenic stem cells grew onto PEG-DA scaffolds. They were attached to the pillars and formed cell-cell interactions. It demonstrates that the fabricated structures have potential to be an interconnection channel network for cell-to-cell interactions, flow transport of nutrients and metabolic waste as well as vascular capillary ingrowth. These results are encouraging for further development of holographic lithography by improving its efficiency for microstructuring three-dimensional scaffolds out of biodegradable hydrogels

Servo-integrated patterned media by hybrid directed self-assembly.

PubMed

Xiao, Shuaigang; Yang, Xiaomin; Steiner, Philip; Hsu, Yautzong; Lee, Kim; Wago, Koichi; Kuo, David

2014-11-25

A hybrid directed self-assembly approach is developed to fabricate unprecedented servo-integrated bit-patterned media templates, by combining sphere-forming block copolymers with 5 teradot/in.(2) resolution capability, nanoimprint and optical lithography with overlay control. Nanoimprint generates prepatterns with different dimensions in the data field and servo field, respectively, and optical lithography controls the selective self-assembly process in either field. Two distinct directed self-assembly techniques, low-topography graphoepitaxy and high-topography graphoepitaxy, are elegantly integrated to create bit-patterned templates with flexible embedded servo information. Spinstand magnetic test at 1 teradot/in.(2) shows a low bit error rate of 10(-2.43), indicating fully functioning bit-patterned media and great potential of this approach for fabricating future ultra-high-density magnetic storage media.

NASA Tech Briefs, June 2003

NASA Technical Reports Server (NTRS)

2003-01-01

Topics covered include: Nulling Infrared Radiometer for Measuring Temperature; The Ames Power Monitoring System; Hot Films on Ceramic Substrates for Measuring Skin Friction; Probe Without Moving Parts Measures Flow Angle; Detecting Conductive Liquid Leaking from Nonconductive Pipe; Adaptive Suppression of Noise in Voice Communications; High-Performance Solid-State W-Band Power Amplifiers; Microbatteries for Combinatorial Studies of Conventional Lithium-Ion Batteries; Correcting for Beam Aberrations in a Beam-Waveguide Antenna; Advanced Rainbow Solar Photovoltaic Arrays; Metal Side Reflectors for Trapping Light in QWIPs; Software for Collaborative Engineering of Launch Rockets; Software Assists in Extensive Environmental Auditing; Software Supports Distributed Operations via the Internet; Software Estimates Costs of Testing Rocket Engines; yourSky: Custom Sky-Image Mosaics via the Internet; Software for Managing Inventory of Flight Hardware; Lower-Conductivity Thermal-Barrier Coatings; Process for Smoothing an Si Substrate after Etching of SiO2; Flexible Composite-Material Pressure Vessel; Treatment to Destroy Chlorohydrocarbon Liquids in the Ground; Noncircular Cross Sections Could Enhance Mixing in Sprays; Small, Untethered, Mobile Roots for Inspecting Gas Pipes; Paint-Overspray Catcher; Preparation of Regular Specimens for Atom Probes; Inverse Tomo-Lithography for Making Microscopic 3D Parts; Predicting and Preventing Incipient Flameout in Combustors; MEMS-Based Piezoelectric/Electrostatic Inchworm Actuator; Metallized Capillaries as Probes for Raman Spectroscopy; Adaptation of Mesoscale Weather Models to Local Forecasting; Aerodynamic Design using Neural Networks; Combining Multiple Gyroscope Outputs for Increased Accuracy; and Improved Collision-Detection Method for Robotic Manipulator.

Recent developments of x-ray lithography in Canada

NASA Astrophysics Data System (ADS)

Chaker, Mohamed; Boily, Stephane; Ginovker, A.; Jean, Alain; Kieffer, Jean-Claude; Mercier, P. P.; Pepin, Henri; Leung, Pak; Currie, John F.; Lafontaine, Hugues

1991-08-01

An overview of current activities in Canada is reported, including x-ray lithography studies based on laser plasma sources and x-ray mask development. In particular, the application of laser plasma sources for x-ray lithography is discussed, taking into account the industrial requirement and the present state of laser technology. The authors describe the development of silicon carbide membranes for x-ray lithography application. SiC films were prepared using either a 100 kHz plasma-enhanced chemical vapor deposition (PECVD) system or a laser ablation technique. These membranes have a relatively large diameter (> 1 in.) and a high optical transparency (> 50%). Experimental studies on stresses in tungsten films deposited with triode sputtering are reported.

Study on photochemical analysis system (VLES) for EUV lithography

NASA Astrophysics Data System (ADS)

Sekiguchi, A.; Kono, Y.; Kadoi, M.; Minami, Y.; Kozawa, T.; Tagawa, S.; Gustafson, D.; Blackborow, P.

2007-03-01

A system for photo-chemical analysis of EUV lithography processes has been developed. This system has consists of 3 units: (1) an exposure that uses the Z-Pinch (Energetiq Tech.) EUV Light source (DPP) to carry out a flood exposure, (2) a measurement system RDA (Litho Tech Japan) for the development rate of photo-resists, and (3) a simulation unit that utilizes PROLITH (KLA-Tencor) to calculate the resist profiles and process latitude using the measured development rate data. With this system, preliminary evaluation of the performance of EUV lithography can be performed without any lithography tool (Stepper and Scanner system) that is capable of imaging and alignment. Profiles for 32 nm line and space pattern are simulated for the EUV resist (Posi-2 resist by TOK) by using VLES that hat has sensitivity at the 13.5nm wavelength. The simulation successfully predicts the resist behavior. Thus it is confirmed that the system enables efficient evaluation of the performance of EUV lithography processes.

Modeling of projection electron lithography

NASA Astrophysics Data System (ADS)

Mack, Chris A.

2000-07-01

Projection Electron Lithography (PEL) has recently become a leading candidate for the next generation of lithography systems after the successful demonstration of SCAPEL by Lucent Technologies and PREVAIL by IBM. These systems use a scattering membrane mask followed by a lens with limited angular acceptance range to form an image of the mask when illuminated by high energy electrons. This paper presents an initial modeling system for such types of projection electron lithography systems. Monte Carlo modeling of electron scattering within the mask structure creates an effective mask 'diffraction' pattern, to borrow the standard optical terminology. A cutoff of this scattered pattern by the imaging 'lens' provides an electron energy distribution striking the wafer. This distribution is then convolved with a 'point spread function,' the results of a Monte Carlo scattering calculation of a point beam of electrons striking the resist coated substrate and including the effects of beam blur. Resist exposure and development models from standard electron beam lithography simulation are used to simulate the final three-dimensional resist profile.

EB and EUV lithography using inedible cellulose-based biomass resist material

NASA Astrophysics Data System (ADS)

Takei, Satoshi; Hanabata, Makoto; Oshima, Akihiro; Kashiwakura, Miki; Kozawa, Takahiro; Tagawa, Seiichi

2016-03-01

The validity of our approach of inedible cellulose-based resist material derived from woody biomass has been confirmed experimentally for the use of pure water in organic solvent-free water spin-coating and tetramethylammonium hydroxide(TMAH)-free water-developable techniques of eco-conscious electron beam (EB) and extreme-ultraviolet (EUV) lithography. The water developable, non-chemically amplified, high sensitive, and negative tone resist material in EB and EUV lithography was developed for environmental affair, safety, easiness of handling, and health of the working people. The inedible cellulose-based biomass resist material was developed by replacing the hydroxyl groups in the beta-linked disaccharides with EB and EUV sensitive groups. The 50-100 nm line and space width, and little footing profiles of cellulose-based biomass resist material on hardmask and layer were resolved at the doses of 10-30 μC/cm2. The eco-conscious lithography techniques was referred to as green EB and EUV lithography using inedible cellulose-based biomass resist material.

Combination photo and electron beam lithography with polymethyl methacrylate (PMMA) resist.

PubMed

Carbaugh, Daniel J; Pandya, Sneha G; Wright, Jason T; Kaya, Savas; Rahman, Faiz

2017-11-10

We describe techniques for performing photolithography and electron beam lithography in succession on the same resist-covered substrate. Larger openings are defined in the resist film through photolithography whereas smaller openings are defined through conventional electron beam lithography. The two processes are carried out one after the other and without an intermediate wet development step. At the conclusion of the two exposures, the resist film is developed once to reveal both large and small openings. Interestingly, these techniques are applicable to both positive and negative tone lithographies with both optical and electron beam exposure. Polymethyl methacrylate, by itself or mixed with a photocatalytic cross-linking agent, is used for this purpose. We demonstrate that such resists are sensitive to both ultraviolet and electron beam irradiation. All four possible combinations, consisting of optical and electron beam lithographies, carried out in positive and negative tone modes have been described. Demonstration grating structures have been shown and process conditions have been described for all four cases.

Fabrication of 0.25-um electrode width SAW filters using x-ray lithography with a laser plasma source

NASA Astrophysics Data System (ADS)

Bobkowski, Romuald; Li, Yunlei; Fedosejevs, Robert; Broughton, James N.

1996-05-01

A process for the fabrication of surface acoustic wave (SAW) devices with line widths of 250 nm and less, based on x-ray lithography using a laser-plasma source has been developed. The x-ray lithography process is based on keV x-ray emission from Cu plasma produced by 15 Hz, 50 ps, 248 nm KrF excimer laser pulses. The full structure of a 2 GHz surface acoustic wave filter with interdigital transducers in a split-electrode geometry has been manufactured. The devices require patterning a 150 nm thick aluminum layer on a LiNbO3 substrate with electrodes 250 nm wide. The manufacturing process has two main steps: x-ray mask fabrication employing e-beam lithography and x-ray lithography to obtain the final device. The x-ray masks are fabricated on 1 micrometers thick membranes of Si2N4. The line patterns on the masks are written into PMMA resist using a scanning electron microscope which has been interfaced to a personal computer equipped to control the x and y scan voltages. The opaque regions of the x-ray mask are then formed by electroplating fine grain gold into the open spaces in the etched PMMA. The mask and sample are mounted in an exposure cassette with a fixed spacer of 10 micrometers separating them. The sample consists of a LiNbO3 substrate coated with Shipley XP90104C x-ray resist which has been previously characterized. The x-ray patterning is carried out in an exposure chamber with flowing helium background gas in order to minimize debris deposition on the filters. After etching the x-ray resist, the final patterns are produced using metallization and a standard lift-off technique. The SAW filters are then bonded and packaged onto impedance matching striplines. The resultant devices are tested using Scalar Network Analyzers. The final devices produced had a center frequency of 1.93 GHz with a bandwidth of 98 MHz, close to the expected performance of our simple design.

Fabrication of Three-Dimensional Imprint Lithography Templates by Colloidal Dispersions

DTIC Science & Technology

2011-03-06

Dispersions A. Marcia Almanza-Workman, Taussig P. Carl, Albert H. Jeans, Robert L. Cobene HP Laboratories HPL-2011-32 Flexible displays, Self aligned...imprint lithography, stamps, fluorothermoplastics, latex Self -aligned imprint lithography (SAIL) enables patterning and alignment of submicron-sized...features on flexible substrates in the roll-to roll (R2R) environment. Soft molds made of elastomers have been used as stamps to pattern three

OML: optical maskless lithography for economic design prototyping and small-volume production

NASA Astrophysics Data System (ADS)

Sandstrom, Tor; Bleeker, Arno; Hintersteiner, Jason; Troost, Kars; Freyer, Jorge; van der Mast, Karel

2004-05-01

The business case for Maskless Lithography is more compelling than ever before, due to more critical processes, rising mask costs and shorter product cycles. The economics of Maskless Lithography gives a crossover volume from Maskless to mask-based lithography at surprisingly many wafers per mask for surprisingly few wafers per hour throughput. Also, small-volume production will in many cases be more economical with Maskless Lithography, even when compared to "shuttle" schemes, reticles with multiple layers, etc. The full benefit of Maskless Lithography is only achievable by duplicating processes that are compatible with volume production processes on conventional scanners. This can be accomplished by the integration of pattern generators based on spatial light modulator technology with state-of-the-art optical scanner systems. This paper reports on the system design of an Optical Maskless Scanner in development by ASML and Micronic: small-field optics with high demagnification, variable NA and illumination schemes, spatial light modulators with millions of MEMS mirrors on CMOS drivers, a data path with a sustained data flow of more than 250 GPixels per second, stitching of sub-fields to scanner fields, and rasterization and writing strategies for throughput and good image fidelity. Predicted lithographic performance based on image simulations is also shown.

Rigorous ILT optimization for advanced patterning and design-process co-optimization

NASA Astrophysics Data System (ADS)

Selinidis, Kosta; Kuechler, Bernd; Cai, Howard; Braam, Kyle; Hoppe, Wolfgang; Domnenko, Vitaly; Poonawala, Amyn; Xiao, Guangming

2018-03-01

Despite the large difficulties involved in extending 193i multiple patterning and the slow ramp of EUV lithography to full manufacturing readiness, the pace of development for new technology node variations has been accelerating. Multiple new variations of new and existing technology nodes have been introduced for a range of device applications; each variation with at least a few new process integration methods, layout constructs and/or design rules. This had led to a strong increase in the demand for predictive technology tools which can be used to quickly guide important patterning and design co-optimization decisions. In this paper, we introduce a novel hybrid predictive patterning method combining two patterning technologies which have each individually been widely used for process tuning, mask correction and process-design cooptimization. These technologies are rigorous lithography simulation and inverse lithography technology (ILT). Rigorous lithography simulation has been extensively used for process development/tuning, lithography tool user setup, photoresist hot-spot detection, photoresist-etch interaction analysis, lithography-TCAD interactions/sensitivities, source optimization and basic lithography design rule exploration. ILT has been extensively used in a range of lithographic areas including logic hot-spot fixing, memory layout correction, dense memory cell optimization, assist feature (AF) optimization, source optimization, complex patterning design rules and design-technology co-optimization (DTCO). The combined optimization capability of these two technologies will therefore have a wide range of useful applications. We investigate the benefits of the new functionality for a few of these advanced applications including correction for photoresist top loss and resist scumming hotspots.

Data sharing system for lithography APC

NASA Astrophysics Data System (ADS)

Kawamura, Eiichi; Teranishi, Yoshiharu; Shimabara, Masanori

2007-03-01

We have developed a simple and cost-effective data sharing system between fabs for lithography advanced process control (APC). Lithography APC requires process flow, inter-layer information, history information, mask information and so on. So, inter-APC data sharing system has become necessary when lots are to be processed in multiple fabs (usually two fabs). The development cost and maintenance cost also have to be taken into account. The system handles minimum information necessary to make trend prediction for the lots. Three types of data have to be shared for precise trend prediction. First one is device information of the lots, e.g., process flow of the device and inter-layer information. Second one is mask information from mask suppliers, e.g., pattern characteristics and pattern widths. Last one is history data of the lots. Device information is electronic file and easy to handle. The electronic file is common between APCs and uploaded into the database. As for mask information sharing, mask information described in common format is obtained via Wide Area Network (WAN) from mask-vender will be stored in the mask-information data server. This information is periodically transferred to one specific lithography-APC server and compiled into the database. This lithography-APC server periodically delivers the mask-information to every other lithography-APC server. Process-history data sharing system mainly consists of function of delivering process-history data. In shipping production lots to another fab, the product-related process-history data is delivered by the lithography-APC server from the shipping site. We have confirmed the function and effectiveness of data sharing systems.

Intregrating metallic wiring with three-dimensional polystyrene colloidal crystals using electron-beam lithography and three-dimensional laser lithography

NASA Astrophysics Data System (ADS)

Tian, Yaolan; Isotalo, Tero J.; Konttinen, Mikko P.; Li, Jiawei; Heiskanen, Samuli; Geng, Zhuoran; Maasilta, Ilari J.

2017-02-01

We demonstrate a method to fabricate narrow, down to a few micron wide metallic leads on top of a three-dimensional (3D) colloidal crystal self-assembled from polystyrene (PS) nanospheres of diameter 260 nm, using electron-beam lithography. This fabrication is not straightforward due to the fact that PS nanospheres cannot usually survive the harsh chemical treatments required in the development and lift-off steps of electron-beam lithography. We solve this problem by increasing the chemical resistance of the PS nanospheres using an additional electron-beam irradiation step, which allows the spheres to retain their shape and their self-assembled structure, even after baking to a temperature of 160 °C, the exposure to the resist developer and the exposure to acetone, all of which are required for the electron-beam lithography step. Moreover, we show that by depositing an aluminum oxide capping layer on top of the colloidal crystal after the e-beam irradiation, the surface is smooth enough so that continuous metal wiring can be deposited by the electron-beam lithography. Finally, we also demonstrate a way to self-assemble PS colloidal crystals into a microscale container, which was fabricated using direct-write 3D laser-lithography. Metallic wiring was also successfully integrated with the combination of a container structure and a PS colloidal crystal. Our goal is to make a device for studies of thermal transport in 3D phononic crystals, but other phononic or photonic crystal applications could also be envisioned.

Lithography for enabling advances in integrated circuits and devices.

PubMed

Garner, C Michael

2012-08-28

Because the transistor was fabricated in volume, lithography has enabled the increase in density of devices and integrated circuits. With the invention of the integrated circuit, lithography enabled the integration of higher densities of field-effect transistors through evolutionary applications of optical lithography. In 1994, the semiconductor industry determined that continuing the increase in density transistors was increasingly difficult and required coordinated development of lithography and process capabilities. It established the US National Technology Roadmap for Semiconductors and this was expanded in 1999 to the International Technology Roadmap for Semiconductors to align multiple industries to provide the complex capabilities to continue increasing the density of integrated circuits to nanometre scales. Since the 1960s, lithography has become increasingly complex with the evolution from contact printers, to steppers, pattern reduction technology at i-line, 248 nm and 193 nm wavelengths, which required dramatic improvements of mask-making technology, photolithography printing and alignment capabilities and photoresist capabilities. At the same time, pattern transfer has evolved from wet etching of features, to plasma etch and more complex etching capabilities to fabricate features that are currently 32 nm in high-volume production. To continue increasing the density of devices and interconnects, new pattern transfer technologies will be needed with options for the future including extreme ultraviolet lithography, imprint technology and directed self-assembly. While complementary metal oxide semiconductors will continue to be extended for many years, these advanced pattern transfer technologies may enable development of novel memory and logic technologies based on different physical phenomena in the future to enhance and extend information processing.

Ultimate intra-wafer critical dimension uniformity control by using lithography and etch tool corrections

NASA Astrophysics Data System (ADS)

Kubis, Michael; Wise, Rich; Reijnen, Liesbeth; Viatkina, Katja; Jaenen, Patrick; Luca, Melisa; Mernier, Guillaume; Chahine, Charlotte; Hellin, David; Kam, Benjamin; Sobieski, Daniel; Vertommen, Johan; Mulkens, Jan; Dusa, Mircea; Dixit, Girish; Shamma, Nader; Leray, Philippe

2016-03-01

With shrinking design rules, the overall patterning requirements are getting aggressively tighter. For the 7-nm node and below, allowable CD uniformity variations are entering the Angstrom region (ref [1]). Optimizing inter- and intra-field CD uniformity of the final pattern requires a holistic tuning of all process steps. In previous work, CD control with either litho cluster or etch tool corrections has been discussed. Today, we present a holistic CD control approach, combining the correction capability of the etch tool with the correction capability of the exposure tool. The study is done on 10-nm logic node wafers, processed with a test vehicle stack patterning sequence. We include wafer-to-wafer and lot-to-lot variation and apply optical scatterometry to characterize the fingerprints. Making use of all available correction capabilities (lithography and etch), we investigated single application of exposure tool corrections and of etch tool corrections as well as combinations of both to reach the lowest CD uniformity. Results of the final pattern uniformity based on single and combined corrections are shown. We conclude on the application of this holistic lithography and etch optimization to 7nm High-Volume manufacturing, paving the way to ultimate within-wafer CD uniformity control.

A novel double patterning approach for 30nm dense holes

NASA Astrophysics Data System (ADS)

Hsu, Dennis Shu-Hao; Wang, Walter; Hsieh, Wei-Hsien; Huang, Chun-Yen; Wu, Wen-Bin; Shih, Chiang-Lin; Shih, Steven

2011-04-01

Double Patterning Technology (DPT) was commonly accepted as the major workhorse beyond water immersion lithography for sub-38nm half-pitch line patterning before the EUV production. For dense hole patterning, classical DPT employs self-aligned spacer deposition and uses the intersection of horizontal and vertical lines to define the desired hole patterns. However, the increase in manufacturing cost and process complexity is tremendous. Several innovative approaches have been proposed and experimented to address the manufacturing and technical challenges. A novel process of double patterned pillars combined image reverse will be proposed for the realization of low cost dense holes in 30nm node DRAM. The nature of pillar formation lithography provides much better optical contrast compared to the counterpart hole patterning with similar CD requirements. By the utilization of a reliable freezing process, double patterned pillars can be readily implemented. A novel image reverse process at the last stage defines the hole patterns with high fidelity. In this paper, several freezing processes for the construction of the double patterned pillars were tested and compared, and 30nm double patterning pillars were demonstrated successfully. A variety of different image reverse processes will be investigated and discussed for their pros and cons. An economic approach with the optimized lithography performance will be proposed for the application of 30nm DRAM node.

Direct-writing lithography using laser diode beam focused with single elliptical microlens

NASA Astrophysics Data System (ADS)

Hasan, Md. Nazmul; Haque, Muttahid-Ull; Trisno, Jonathan; Lee, Yung-Chun

2015-10-01

A lithography method is proposed for arbitrary patterning using an elliptically diverging laser diode beam focused with a single planoconvex elliptical microlens. Simulations are performed to model the propagation properties of the laser beam and to design the elliptical microlens, which has two different profiles in the x- and y-axis directions. The microlens is fabricated using an excimer laser dragging method and is then attached to the laser diode using double-sided optically cleared adhesive (OCA) tape. Notably, the use of OCA tape removes the need for a complicated alignment procedure and thus significantly reduces the assembly cost. The minimum focused spot of the laser diode beam is investigated by performing single-shot exposure tests on a photoresist (PR) layer. Finally, the practical feasibility of this lithography technique to generate an arbitrary pattern is demonstrated by dotted and continuous features through thin chromium layer deposition on PR and a metal lift-off process. The results show that the minimum feature size for the dotted patterns is around 6.23 μm, while the minimum linewidths for continuous patterns is 6.44 μm. In other words, the proposed focusing technique has significant potential for writing any arbitrary high-resolution pattern for applications like printed circuit board fabrication.

Wiring Together Synthetic Bacterial Consortia to Create a Biological Integrated Circuit.

PubMed

Perry, Nicolas; Nelson, Edward M; Timp, Gregory

2016-12-16

The promise of adapting biology to information processing will not be realized until engineered gene circuits, operating in different cell populations, can be wired together to express a predictable function. Here, elementary biological integrated circuits (BICs), consisting of two sets of transmitter and receiver gene circuit modules with embedded memory placed in separate cell populations, were meticulously assembled using live cell lithography and wired together by the mass transport of quorum-sensing (QS) signal molecules to form two isolated communication links (comlinks). The comlink dynamics were tested by broadcasting "clock" pulses of inducers into the networks and measuring the responses of functionally linked fluorescent reporters, and then modeled through simulations that realistically captured the protein production and molecular transport. These results show that the comlinks were isolated and each mimicked aspects of the synchronous, sequential networks used in digital computing. The observations about the flow conditions, derived from numerical simulations, and the biofilm architectures that foster or silence cell-to-cell communications have implications for everything from decontamination of drinking water to bacterial virulence.

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

Tichenor, Daniel A.; Ray-Chaudhuri, Avijit K.; Replogle, William C.

The Engineering Test Stand (ETS) is a developmental lithography tool designed to demonstrate full-field EUV imaging and provide data for commercial-tool development. In the first phase of integration, currently in progress, the ETS is configured using a developmental projection system, while fabrication of an improved projection system proceeds in parallel. The optics in the second projection system have been fabricated to tighter specifications for improved resolution and reduced flare. The projection system is a 4-mirror, 4x-reduction, ring-field design having a numeral aperture of 0.1, which supports 70 nm resolution at a k{sub 1} of 0.52. The illuminator produces 13.4 nmmore » radiation from a laser-produced plasma, directs the radiation onto an arc-shaped field of view, and provides an effective fill factor at the pupil plane of 0.7. The ETS is designed for full-field images in step-and-scan mode using vacuum-compatible, magnetically levitated, scanning stages. This paper describes system performance observed during the first phase of integration, including static resist images of 100 nm isolated and dense features.« less

Integrated approach to improving local CD uniformity in EUV patterning

NASA Astrophysics Data System (ADS)

Liang, Andrew; Hermans, Jan; Tran, Timothy; Viatkina, Katja; Liang, Chen-Wei; Ward, Brandon; Chuang, Steven; Yu, Jengyi; Harm, Greg; Vandereyken, Jelle; Rio, David; Kubis, Michael; Tan, Samantha; Dusa, Mircea; Singhal, Akhil; van Schravendijk, Bart; Dixit, Girish; Shamma, Nader

2017-03-01

Extreme ultraviolet (EUV) lithography is crucial to enabling technology scaling in pitch and critical dimension (CD). Currently, one of the key challenges of introducing EUV lithography to high volume manufacturing (HVM) is throughput, which requires high source power and high sensitivity chemically amplified photoresists. Important limiters of high sensitivity chemically amplified resists (CAR) are the effects of photon shot noise and resist blur on the number of photons received and of photoacids generated per feature, especially at the pitches required for 7 nm and 5 nm advanced technology nodes. These stochastic effects are reflected in via structures as hole-to-hole CD variation or local CD uniformity (LCDU). Here, we demonstrate a synergy of film stack deposition, EUV lithography, and plasma etch techniques to improve LCDU, which allows the use of high sensitivity resists required for the introduction of EUV HVM. Thus, to improve LCDU to a level required by 5 nm node and beyond, film stack deposition, EUV lithography, and plasma etch processes were combined and co-optimized to enhance LCDU reduction from synergies. Test wafers were created by depositing a pattern transfer stack on a substrate representative of a 5 nm node target layer. The pattern transfer stack consisted of an atomically smooth adhesion layer and two hardmasks and was deposited using the Lam VECTOR PECVD product family. These layers were designed to mitigate hole roughness, absorb out-of-band radiation, and provide additional outlets for etch to improve LCDU and control hole CD. These wafers were then exposed through an ASML NXE3350B EUV scanner using a variety of advanced positive tone EUV CAR. They were finally etched to the target substrate using Lam Flex dielectric etch and Kiyo conductor etch systems. Metrology methodologies to assess dimensional metrics as well as chip performance and defectivity were investigated to enable repeatable patterning process development. Illumination conditions in EUV lithography were optimized to improve normalized image log slope (NILS), which is expected to reduce shot noise related effects. It can be seen that the EUV imaging contrast improvement can further reduce post-develop LCDU from 4.1 nm to 3.9 nm and from 2.8 nm to 2.6 nm. In parallel, etch processes were developed to further reduce LCDU, to control CD, and to transfer these improvements into the final target substrate. We also demonstrate that increasing post-develop CD through dose adjustment can enhance the LCDU reduction from etch. Similar trends were also observed in different pitches down to 40 nm. The solutions demonstrated here are critical to the introduction of EUV lithography in high volume manufacturing. It can be seen that through a synergistic deposition, lithography, and etch optimization, LCDU at a 40 nm pitch can be improved to 1.6 nm (3-sigma) in a target oxide layer and to 1.4 nm (3-sigma) at the photoresist layer.

First 65nm tape-out using inverse lithography technology (ILT)

NASA Astrophysics Data System (ADS)

Hung, Chi-Yuan; Zhang, Bin; Tang, Deming; Guo, Eric; Pang, Linyong; Liu, Yong; Moore, Andrew; Wang, Kechang

2005-11-01

This paper presents SMIC's first 65nm tape out results, in particularly, using ILT. ILT mathematically determines the mask features that produce the desired on-wafer results with best wafer pattern fidelity, largest process window or both. SMIC applied it to its first 65nm tape-out to study ILT performance and benefits for deep sub-wavelength lithography. SMIC selected 3 SRAM designs as the first test case, because SRAM bit-cells contain features which are challenging lithographically. Mask patterns generated from both conventional OPC and ILT were placed on the mask side-by-side. Mask manufacturability (including fracturing, writing time, inspection, and metrology) and wafer print performance of ILT were studied. The results demonstrated that ILT achieved better CD accuracy, produced substantially larger process window than conventional OPC, and met SMIC's 65nm process window requirements.

Computational method for the correction of proximity effect in electron-beam lithography (Poster Paper)

NASA Astrophysics Data System (ADS)

Chang, Chih-Yuan; Owen, Gerry; Pease, Roger Fabian W.; Kailath, Thomas

1992-07-01

Dose correction is commonly used to compensate for the proximity effect in electron lithography. The computation of the required dose modulation is usually carried out using 'self-consistent' algorithms that work by solving a large number of simultaneous linear equations. However, there are two major drawbacks: the resulting correction is not exact, and the computation time is excessively long. A computational scheme, as shown in Figure 1, has been devised to eliminate this problem by the deconvolution of the point spread function in the pattern domain. The method is iterative, based on a steepest descent algorithm. The scheme has been successfully tested on a simple pattern with a minimum feature size 0.5 micrometers , exposed on a MEBES tool at 10 KeV in 0.2 micrometers of PMMA resist on a silicon substrate.

Gold-implanted shallow conducting layers in polymethylmethacrylate

NASA Astrophysics Data System (ADS)

Teixeira, F. S.; Salvadori, M. C.; Cattani, M.; Brown, I. G.

2009-03-01

PMMA (polymethylmethacrylate) was ion implanted with gold at very low energy and over a range of different doses using a filtered cathodic arc metal plasma system. A nanometer scale conducting layer was formed, fully buried below the polymer surface at low implantation dose, and evolving to include a gold surface layer as the dose was increased. Depth profiles of the implanted material were calculated using the Dynamic TRIM computer simulation program. The electrical conductivity of the gold-implanted PMMA was measured in situ as a function of dose. Samples formed at a number of different doses were subsequently characterized by Rutherford backscattering spectrometry, and test patterns were formed on the polymer by electron beam lithography. Lithographic patterns were imaged by atomic force microscopy and demonstrated that the contrast properties of the lithography were well maintained in the surface-modified PMMA.

Optically resilient 3D micro-optics on the tips of optical fibers

NASA Astrophysics Data System (ADS)

Jonušauskas, Linas

2017-05-01

In this paper we present a study aimed at investigating an optical resiliency of polymers that could be applied in 3D femtosecond laser lithography. These include popular in lithography SU8 and OrmoClear as well as hybrid organic-inorganic zirconium containing SZ2080. We show that latter material in its pure (non-photosensitized) form has the best optical resiliency out of all tested materials. Furthermore, its 3D structurability is investigated. Despite threshold-like quality degradation outside fabrication window, we show that this material is suitable for creating complex 3D structures on the tips of optical fibers. Overall it is demonstrated, that unique capability of 3DLL to structure pure materials can lead to very compact functional fiber-based devices that could withstand high (GW/cm2) light intensities.

Hydrophilic/hydrophobic surface modification impact on colloid lithography: Schottky-like defects, dislocation, and ideal distribution

NASA Astrophysics Data System (ADS)

Burtsev, Vasilii; Marchuk, Valentina; Kugaevskiy, Artem; Guselnikova, Olga; Elashnikov, Roman; Miliutina, Elena; Postnikov, Pavel; Svorcik, Vaclav; Lyutakov, Oleksiy

2018-03-01

Nano-spheres lithography is actually considered as a powerful tool to manufacture various periodic structures with a wide potential in the field of nano- and micro-fabrication. However, during self-assembling of colloid microspheres, various defects and mismatches can appear. In this work the size and quality of single-domains of closed-packed polystyrene (PS), grown up on thin Au layers modified by hydrophilic or hydrophobic functional groups via diazonium chemistry was studied. The effects of the surface modification on the quality and single-domain size of polystyrene (PS) microspheres array were investigated and discussed. Modified surfaces were characterized using the AFM and wettability tests. PS colloidal suspension was deposited using the drop evaporation method. Resulted PS microspheres array was characterized using the SEM, AFM and confocal microscopy technique.

Interconnections in ULSI: Correlation and Crosstalk

DTIC Science & Technology

1992-12-31

basic tool is electron beam lithography of poly (methyl methacrylate) (PMMA). The two central issues to creating very dense patterns as described...direct lithographic techniques. Fig. 2: Ti/Au (2 nm/15 nm) grating with 38 nm pitch fabricated by electron beam lithography using our high contrast...G. H. Bernstein, G. Bazan, and D. A. Hill, "Spatial Density of Lines in PMMA by Electron Beam Lithography ," Journal of Vacuum Science and Technology

Optofluidic encapsulation and manipulation of silicon microchips using image processing based optofluidic maskless lithography and railed microfluidics.

PubMed

Chung, Su Eun; Lee, Seung Ah; Kim, Jiyun; Kwon, Sunghoon

2009-10-07

We demonstrate optofluidic encapsulation of silicon microchips using image processing based optofluidic maskless lithography and manipulation using railed microfluidics. Optofluidic maskless lithography is a dynamic photopolymerization technique of free-floating microstructures within a fluidic channel using spatial light modulator. Using optofluidic maskless lithography via computer-vision aided image processing, polymer encapsulants are fabricated for chip protection and guiding-fins for efficient chip conveying within a fluidic channel. Encapsulated silicon chips with guiding-fins are assembled using railed microfluidics, which is an efficient guiding and heterogeneous self-assembly system of microcomponents. With our technology, externally fabricated silicon microchips are encapsulated, fluidically guided and self-assembled potentially enabling low cost fluidic manipulation and assembly of integrated circuits.

Development of low friction snake-inspired deterministic textured surfaces

NASA Astrophysics Data System (ADS)

Cuervo, P.; López, D. A.; Cano, J. P.; Sánchez, J. C.; Rudas, S.; Estupiñán, H.; Toro, A.; Abdel-Aal, H. A.

2016-06-01

The use of surface texturization to reduce friction in sliding interfaces has proved successful in some tribological applications. However, it is still difficult to achieve robust surface texturing with controlled designer-functionalities. This is because the current existing gap between enabling texturization technologies and surface design paradigms. Surface engineering, however, is advanced in natural surface constructs especially within legless reptiles. Many intriguing features facilitate the tribology of such animals so that it is feasible to discover the essence of their surface construction. In this work, we report on the tribological behavior of a novel class of surfaces of which the spatial dimensions of the textural patterns originate from micro-scale features present within the ventral scales of pre-selected snake species. Mask lithography was used to produce implement elliptical texturizing patterns on the surface of titanium alloy (Ti6Al4V) pins. To study the tribological behavior of the texturized pins, pin-on-disc tests were carried out with the pins sliding against ultra-high molecular weight polyethylene discs with no lubrication. For comparison, two non-texturized samples were also tested under the same conditions. The results show the feasibility of the texturization technique based on the coefficient of friction of the textured surfaces to be consistently lower than that of the non-texturized samples.

X-ray/EUV optics for astronomy, microscopy, polarimetry, and projection lithography; Proceedings of the Meeting, San Diego, CA, July 9-13, 1990

NASA Technical Reports Server (NTRS)

Hoover, Richard B. (Editor); Walker, Arthur B. C., Jr. (Editor)

1991-01-01

Topics discussed in this issue include the fabrication of multilayer X-ray/EUV coatings; the design, characterization, and test of multilayer X-ray/EUV coatings; multilayer X-ray/EUV monochromators and imaging microscopes; X-ray/EUV telescopes; the test and calibration performance of X-ray/EUV instruments; XUV/soft X-ray projection lithography; X-ray/EUV space observatories and missions; X-ray/EUV telescopes for solar research; X-ray/EUV polarimetry; X-ray/EUV spectrographs; and X-ray/EUV filters and gratings. Papers are presented on the deposition-controlled uniformity of multilayer mirrors, interfaces in Mo/Si multilayers, the design and analysis of an aspherical multilayer imaging X-ray microscope, recent developments in the production of thin X-ray reflecting foils, and the ultraprecise scanning technology. Consideration is also given to an active sun telescope array, the fabrication and performance at 1.33 nm of a 0.24-micron-period multilayer grating, a cylindrical proportional counter for X-ray polarimetry, and the design and analysis of the reflection grating arrays for the X-Ray Multi-Mirror Mission.

ILT for double exposure lithography with conventional and novel materials

NASA Astrophysics Data System (ADS)

Poonawala, Amyn; Borodovsky, Yan; Milanfar, Peyman

2007-03-01

Multiple paths exists to provide lithography solutions pursuant to Moore's Law for next 3-5 generations of technology, yet each of those paths inevitably leads to solutions eventually requiring patterning at k I < 0.30 and below. In this article, we explore double exposure single development lithography for k I >= 0.25 (using conventional resist) and k1 < 0.25 (using new out-of-sight out-of-mind materials). For the case of k I >= 0.25, we propose a novel double exposure inverse lithography technique (ILT) to split the pattern. Our algorithm is based on our earlier proposed single exposure ILT framework, and works by decomposing the aerial image (instead of the target pattern) into two parts. It also resolves the phase conflicts automatically as part of the decomposition, and the combined aerial image obtained using the estimated masks has a superior contrast. For the case of k I < 0.25, we focus on analyzing the use of various dual patterning techniques enabled by the use of hypothetic materials with properties that allow for the violation of the linear superposition of intensities from the two exposures. We investigate the possible use of two materials: contrast enhancement layer (CEL) and two-photon absorption resists. We propose a mathematical model for CEL, define its characteristic properties, and derive fundamental bounds on the improvement in image log-slope. Simulation results demonstrate that double exposure single development lithography using CEL enables printing 80nm gratings using dry lithography. We also combine ILT, CEL, and DEL to synthesize 2-D patterns with k I = 0.185. Finally, we discuss the viability of two-photon absorption resists for double exposure lithography.

Multi-shaped beam: development status and update on lithography results

NASA Astrophysics Data System (ADS)

Slodowski, Matthias; Doering, Hans-Joachim; Dorl, Wolfgang; Stolberg, Ines A.

2011-04-01

According to the ITRS [1] photo mask is a significant challenge for the 22nm technology node requirements and beyond. Mask making capability and cost escalation continue to be critical for future lithography progress. On the technological side mask specifications and complexity have increased more quickly than the half-pitch requirements on the wafer designated by the roadmap due to advanced optical proximity correction and double patterning demands. From the economical perspective mask costs have significantly increased each generation, in which mask writing represents a major portion. The availability of a multi-electron-beam lithography system for mask write application is considered a potential solution to overcome these challenges [2, 3]. In this paper an update of the development status of a full-package high-throughput multi electron-beam writer, called Multi Shaped Beam (MSB), will be presented. Lithography performance results, which are most relevant for mask writing applications, will be disclosed. The MSB technology is an evolutionary development of the matured single Variable Shaped Beam (VSB) technology. An arrangement of Multi Deflection Arrays (MDA) allows operation with multiple shaped beams of variable size, which can be deflected and controlled individually [4]. This evolutionary MSB approach is associated with a lower level of risk and a relatively short time to implementation compared to the known revolutionary concepts [3, 5, 6]. Lithography performance is demonstrated through exposed pattern. Further details of the substrate positioning platform performance will be disclosed. It will become apparent that the MSB operational mode enables lithography on the same and higher performance level compared to single VSB and that there are no specific additional lithography challenges existing beside those which have already been addressed [1].

Mix & match electron beam & scanning probe lithography for high throughput sub-10 nm lithography

NASA Astrophysics Data System (ADS)

Kaestner, Marcus; Hofer, Manuel; Rangelow, Ivo W.

2013-03-01

The prosperous demonstration of a technique able to produce features with single nanometer (SN) resolution could guide the semiconductor industry into the desired beyond CMOS era. In the lithographic community immense efforts are being made to develop extreme ultra-violet lithography (EUVL) and multiple-e-beam direct-write systems as possible successor for next generation lithography (NGL). However, patterning below 20 nm resolution and sub-10 nm overlay alignment accuracy becomes an extremely challenging quest. Herein, the combination of electron beam lithography (EBL) or EUVL with the outstanding capabilities of closed-loop scanning proximal probe nanolithography (SPL) reveals a promising way to improve both patterning resolution and reproducibility in combination with excellent overlay and placement accuracy. In particular, the imaging and lithographic resolution capabilities provided by scanning probe microscopy (SPM) methods touches the atomic level, which expresses the theoretical limit of constructing nanoelectronic devices. Furthermore, the symbiosis between EBL (EUVL) and SPL expands the process window of EBL (EUVL) far beyond state-of-the-art allowing SPL-based pre- and post-patterning of EBL (EUVL) written features at critical dimension level with theoretically nanometer precise pattern overlay alignment. Moreover, we can modify the EBL (EUVL) pattern before as well as after the development step. In this paper we demonstrate proof of concept using the ultra-high resolution molecular glass resist calixarene. Therefor we applied Gaussian E-beam lithography system operating at 10 keV and a home-developed SPL set-up. The introduced Mix and Match lithography strategy enables a powerful use of our SPL set-up especially as post-patterning tool for inspection and repair functions below the sub-10 nm critical dimension level.

Laser-ablative engineering of phase singularities in plasmonic metamaterial arrays for biosensing applications

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

Aristov, Andrey I.; Kabashin, Andrei V., E-mail: kabashin@lp3.univ-mrs.fr; Zywietz, Urs

2014-02-17

By using methods of laser-induced transfer combined with nanoparticle lithography, we design and fabricate large-area gold nanoparticle-based metamaterial arrays exhibiting extreme Heaviside-like phase jumps in reflected light due to a strong diffractive coupling of localized plasmons. When employed in sensing schemes, these phase singularities provide the sensitivity of 5 × 10{sup 4} deg. of phase shift per refractive index unit change that is comparable with best values reported for plasmonic biosensors. The implementation of sensor platforms on the basis of such metamaterial arrays promises a drastic improvement of sensitivity and cost efficiency of plasmonic biosensing devices.

Design and manufacture of optical system for use in ultraviolet lithography with the free-electron laser

NASA Astrophysics Data System (ADS)

Byrd, Donald A.; Viswanathan, Vriddhachalam K.; Woodfin, Gregg L.; Horn, William W.; Lazazzera, Vito J.; Schmell, Rodney A.

1993-08-01

At Los Alamos National Laboratory, we are preparing to image submicrometer-size features using the Free Electron Laser (FEL) operating at 248 nm. This article describes the optical transfer systems that were designed to relay the ultraviolet (UV) optical output of the FEL, resulting in expected imaged feature sizes in the range 0.3 - 0.5 micrometers . Nearly all optical subsystems are reflective, and once the coatings were optimized any optical wavelength could be used. All refractive optics were UV-grade fused silica. The optical design, engineering, and manufacture of the various component systems are described along with some experimental results.

Low thermal distortion Extreme-UV lithography reticle and method

DOEpatents

Gianoulakis, Steven E.; Ray-Chaudhuri, Avijit K.

2002-01-01

Thermal distortion of reticles or masks can be significantly reduced by emissivity engineering, i.e., the selective placement or omission of coatings on the reticle. Reflective reticles so fabricated exhibit enhanced heat transfer thereby reducing the level of thermal distortion and ultimately improving the quality of the transcription of the reticle pattern onto the wafer. Reflective reticles include a substrate having an active region that defines the mask pattern and non-active region(s) that are characterized by a surface that has a higher emissivity than that of the active region. The non-active regions are not coated with the radiation reflective material.

Nanoscale-Barrier Formation Induced by Low-Dose Electron-Beam Exposure in Ultrathin MoS2 Transistors.

PubMed

Matsunaga, Masahiro; Higuchi, Ayaka; He, Guanchen; Yamada, Tetsushi; Krüger, Peter; Ochiai, Yuichi; Gong, Yongji; Vajtai, Robert; Ajayan, Pulickel M; Bird, Jonathan P; Aoki, Nobuyuki

2016-10-05

Utilizing an innovative combination of scanning-probe and spectroscopic techniques, supported by first-principles calculations, we demonstrate how electron-beam exposure of field-effect transistors, implemented from ultrathin molybdenum disulfide (MoS 2 ), may cause nanoscale structural modifications that in turn significantly modify the electrical operation of these devices. Quite surprisingly, these modifications are induced by even the relatively low electron doses used in conventional electron-beam lithography, which are found to induce compressive strain in the atomically thin MoS 2 . Likely arising from sulfur-vacancy formation in the exposed regions, the strain gives rise to a local widening of the MoS 2 bandgap, an idea that is supported both by our experiment and by the results of first-principles calculations. A nanoscale potential barrier develops at the boundary between exposed and unexposed regions and may cause extrinsic variations in the resulting electrical characteristics exhibited by the transistor. The widespread use of electron-beam lithography in nanofabrication implies that the presence of such strain must be carefully considered when seeking to harness the potential of atomically thin transistors. At the same time, this work also promises the possibility of exploiting the strain as a means to achieve "bandstructure engineering" in such devices.

Grayscale lithography-automated mask generation for complex three-dimensional topography

NASA Astrophysics Data System (ADS)

Loomis, James; Ratnayake, Dilan; McKenna, Curtis; Walsh, Kevin M.

2016-01-01

Grayscale lithography is a relatively underutilized technique that enables fabrication of three-dimensional (3-D) microstructures in photosensitive polymers (photoresists). By spatially modulating ultraviolet (UV) dosage during the writing process, one can vary the depth at which photoresist is developed. This means complex structures and bioinspired designs can readily be produced that would otherwise be cost prohibitive or too time intensive to fabricate. The main barrier to widespread grayscale implementation, however, stems from the laborious generation of mask files required to create complex surface topography. We present a process and associated software utility for automatically generating grayscale mask files from 3-D models created within industry-standard computer-aided design (CAD) suites. By shifting the microelectromechanical systems (MEMS) design onus to commonly used CAD programs ideal for complex surfacing, engineering professionals already familiar with traditional 3-D CAD software can readily utilize their pre-existing skills to make valuable contributions to the MEMS community. Our conversion process is demonstrated by prototyping several samples on a laser pattern generator-capital equipment already in use in many foundries. Finally, an empirical calibration technique is shown that compensates for nonlinear relationships between UV exposure intensity and photoresist development depth as well as a thermal reflow technique to help smooth microstructure surfaces.

Ion beam lithography system

DOEpatents

Leung, Ka-Ngo

2005-08-02

A maskless plasma-formed ion beam lithography tool provides for patterning of sub-50 nm features on large area flat or curved substrate surfaces. The system is very compact and does not require an accelerator column and electrostatic beam scanning components. The patterns are formed by switching beamlets on or off from a two electrode blanking system with the substrate being scanned mechanically in one dimension. This arrangement can provide a maskless nano-beam lithography tool for economic and high throughput processing.

Optical force stamping lithography

PubMed Central

Nedev, Spas; Urban, Alexander S.; Lutich, Andrey A.; Feldmann, Jochen

2013-01-01

Here we introduce a new paradigm of far-field optical lithography, optical force stamping lithography. The approach employs optical forces exerted by a spatially modulated light field on colloidal nanoparticles to rapidly stamp large arbitrary patterns comprised of single nanoparticles onto a substrate with a single-nanoparticle positioning accuracy well beyond the diffraction limit. Because the process is all-optical, the stamping pattern can be changed almost instantly and there is no constraint on the type of nanoparticle or substrates used. PMID:21992538

LENS (lithography enhancement toward nano scale): a European project to support double exposure and double patterning technology development

NASA Astrophysics Data System (ADS)

Cantu, Pietro; Baldi, Livio; Piacentini, Paolo; Sytsma, Joost; Le Gratiet, Bertrand; Gaugiran, Stéphanie; Wong, Patrick; Miyashita, Hiroyuki; Atzei, Luisa R.; Buch, Xavier; Verkleij, Dick; Toublan, Olivier; Perez-Murano, Francesco; Mecerreyes, David

2010-04-01

In 2009 a new European initiative on Double Patterning and Double Exposure lithography process development was started in the framework of the ENIAC Joint Undertaking. The project, named LENS (Lithography Enhancement Towards Nano Scale), involves twelve companies from five different European Countries (Italy, Netherlands, France, Belgium Spain; includes: IC makers (Numonyx and STMicroelectronics), a group of equipment and materials companies (ASML, Lam Research srl, JSR, FEI), a mask maker (Dai Nippon Photomask Europe), an EDA company (Mentor Graphics) and four research and development institutes (CEA-Leti, IMEC, Centro Nacional de Microelectrónica, CIDETEC). The LENS project aims to develop and integrate the overall infrastructure required to reach patterning resolutions required by 32nm and 22nm technology nodes through the double patterning and pitch doubling technologies on existing conventional immersion exposure tools, with the purpose to allow the timely development of 32nm and 22nm technology nodes for memories and logic devices, providing a safe alternative to EUV, Higher Refraction Index Fluids Immersion Lithography and maskless lithography, which appear to be still far from maturity. The project will cover the whole lithography supply chain including design, masks, materials, exposure tools, process integration, metrology and its final objective is the demonstration of 22nm node patterning on available 1.35 NA immersion tools on high complexity mask set.

Electron beam mask writer EBM-9500 for logic 7nm node generation

NASA Astrophysics Data System (ADS)

Matsui, Hideki; Kamikubo, Takashi; Nakahashi, Satoshi; Nomura, Haruyuki; Nakayamada, Noriaki; Suganuma, Mizuna; Kato, Yasuo; Yashima, Jun; Katsap, Victor; Saito, Kenichi; Kobayashi, Ryoei; Miyamoto, Nobuo; Ogasawara, Munehiro

2016-10-01

Semiconductor scaling is slowing down because of difficulties of device manufacturing below logic 7nm node generation. Various lithography candidates which include ArF immersion with resolution enhancement technology (like Inversed Lithography technology), Extreme Ultra Violet lithography and Nano Imprint lithography are being developed to address the situation. In such advanced lithography, shot counts of mask patterns are estimated to increase explosively in critical layers, and then it is hoped that multi beam mask writer (MBMW) is released to handle them within realistic write time. However, ArF immersion technology with multiple patterning will continue to be a mainstream lithography solution for most of the layers. Then, the shot counts in less critical layers are estimated to be stable because of the limitation of resolution in ArF immersion technology. Therefore, single beam mask writer (SBMW) can play an important role for mask production still, relative to MBMW. Also the demand of SBMW seems actually strong for the logic 7nm node. To realize this, we have developed a new SBMW, EBM-9500 for mask fabrication in this generation. A newly introduced electron beam source enables higher current density of 1200A/cm2. Heating effect correction function has also been newly introduced to satisfy the requirements for both pattern accuracy and throughput. In this paper, we will report the configuration and performance of EBM-9500.

Full-chip level MEEF analysis using model based lithography verification

NASA Astrophysics Data System (ADS)

Kim, Juhwan; Wang, Lantian; Zhang, Daniel; Tang, Zongwu

2005-11-01

MEEF (Mask Error Enhancement Factor) has become a critical factor in CD uniformity control since optical lithography process moved to sub-resolution era. A lot of studies have been done by quantifying the impact of the mask CD (Critical Dimension) errors on the wafer CD errors1-2. However, the benefits from those studies were restricted only to small pattern areas of the full-chip data due to long simulation time. As fast turn around time can be achieved for the complicated verifications on very large data by linearly scalable distributed processing technology, model-based lithography verification becomes feasible for various types of applications such as post mask synthesis data sign off for mask tape out in production and lithography process development with full-chip data3,4,5. In this study, we introduced two useful methodologies for the full-chip level verification of mask error impact on wafer lithography patterning process. One methodology is to check MEEF distribution in addition to CD distribution through process window, which can be used for RET/OPC optimization at R&D stage. The other is to check mask error sensitivity on potential pinch and bridge hotspots through lithography process variation, where the outputs can be passed on to Mask CD metrology to add CD measurements on those hotspot locations. Two different OPC data were compared using the two methodologies in this study.

Theoretical study of fabrication of line-and-space patterns with 7 nm quarter-pitch using electron beam lithography with chemically amplified resist process: III. Post exposure baking on quartz substrates

NASA Astrophysics Data System (ADS)

Kozawa, Takahiro

2015-09-01

Electron beam (EB) lithography is a key technology for the fabrication of photomasks for ArF immersion and extreme ultraviolet (EUV) lithography and molds for nanoimprint lithography. In this study, the temporal change in the chemical gradient of line-and-space patterns with a 7 nm quarter-pitch (7 nm space width and 21 nm line width) was calculated until it became constant, independently of postexposure baking (PEB) time, to clarify the feasibility of single nano patterning on quartz substrates using EB lithography with chemically amplified resist processes. When the quencher diffusion constant is the same as the acid diffusion constant, the maximum chemical gradient of the line-and-space pattern with a 7 nm quarter-pitch did not differ much from that with a 14 nm half-pitch under the condition described above. Also, from the viewpoint of process control, a low quencher diffusion constant is considered to be preferable for the fabrication of line-and-space patterns with a 7 nm quarter-pitch on quartz substrates.

Pushing the plasmonic imaging nanolithography to nano-manufacturing

NASA Astrophysics Data System (ADS)

Gao, Ping; Li, Xiong; Zhao, Zeyu; Ma, Xiaoliang; Pu, Mingbo; Wang, Changtao; Luo, Xiangang

2017-12-01

Suffering from the so-called diffraction limit, the minimum resolution of conventional photolithography is limited to λ / 2 or λ / 4, where λ is the incident wavelength. The physical mechanism of this limit lies at the fact that the evanescent waves that carry subwavelength information of the object decay exponentially in a medium, and cannot reach the image plane. Surface plasmons (SPs) are non-radiative electromagnetic waves that propagate along the interface between metal and dielectric, which exhibits unique sub-diffraction optical characteristics. In recent years, benefiting from SPs' features, researchers have proposed a variety of plasmonic lithography methods in the manner of interference, imaging and direct writing, and have demonstrated that sub-diffraction resolution could be achieved by theoretical simulations or experiments. Among the various plasmonic lithography modes, plasmonic imaging lithography seems to be of particular importance for applications due to its compatibility with conventional lithography. Recent results show that the half pitch of nanograting can be shrinked down to 22 nm and even 16 nm. This paper will give an overview of research progress, representative achievements of plasmonic imaging lithography, the remained problems and outlook of further developments.

Characterizing polarized illumination in high numerical aperture optical lithography with phase shifting masks

NASA Astrophysics Data System (ADS)

McIntyre, Gregory Russell

The primary objective of this dissertation is to develop the phase shifting mask (PSM) as a precision instrument to characterize effects in optical lithography related to the use of polarized partially coherent illumination. The intent is to provide an in-situ characterization technique to add to the lithographer's tool-kit to help enable the stable and repeatable mass production of integrated circuits with feature sizes approaching 1/6th the wavelength of light being used. A series of complex-valued mathematical functions have been derived from basic principles and recent advances in photomask fabrication technology have enabled their implementation with four-phase mask making. When located in the object plane of an imaging system, these test functions serve to engineer a wavefiront that interacts with one particular optical effect, creating a measurable signal in the image plane. In most cases, these test patterns leverage proximity effects to create a central image intensity and are theoretically the most sensitive to the desired effect. Five novel classes of test patterns have been developed for in-situ characterization. The first two classes, The Linear Phase Grating (LPG) and Linear Phase Ring (LPR), both serve to characterize illumination angular distribution and uniformity by creating signals dependent on illumination angular frequency. The third class consists of the Radial Phase Grating (RPG) and Proximity Effect Polarization Analyzers (PEPA), which each create a polarization-dependent signal by taking advantage of the image reversal of one polarization component at high numerical aperture (NA). PSM Polarimetry employs a series of these patterns to form a complete polarization characterization of any arbitrary illumination scheme. The fourth and fifth classes employ sub-resolution interferometric reference probes to coherently interact with proximity effect spillover from a surrounding pattern. They measure the effective phase and transmission of the shifted regions of an alternating PSM and projection lens birefringence, respectively. A secondary objective of this dissertation has been to leverage some of these functions to extend the application of pattern matching software to rapidly identify areas in a circuit design layout that may be vulnerable to polarization and high-NA effects. Additionally, polarization aberrations have been investigated, as they may become important with hyper-NA imaging systems. Three multi-phase test reticles have been developed for this thesis and have pushed the limits of photomask fabrication. Coupled with a variety of experimental and simulation studies at 193nm wavelength, they have validated the scientific principles of the PSM monitors and have offered unique insight into implementation issues such as electromagnetic (EM) effects and mask making tolerances. Although all five classes are novel theoretical concepts, it is believed that PSM Polarimetry is commercially viable. Despite a 70% loss of sensitivity due to mask making limitations and a 20% loss due to EM effects, it can likely still monitor polarization to within 2%. Experimental results are comparable to the only other known technique, which requires special equipment. Taken collectively, the five novel classes of PSM monitors offer the lithographer an independent tool-kit to ensure proper tool operation. They also provide circuit designers an understanding of the impact of imaging on layouts. Although they have been developed for optical lithography, their principles are relevant to any image-forming optical system and are likely to find applications in other fields of optics or acoustics.

Rapid fabrication of microfluidic chips based on the simplest LED lithography

NASA Astrophysics Data System (ADS)

Li, Yue; Wu, Ping; Luo, Zhaofeng; Ren, Yuxuan; Liao, Meixiang; Feng, Lili; Li, Yuting; He, Liqun

2015-05-01

Microfluidic chips are generally fabricated by a soft lithography method employing commercial lithography equipment. These heavy machines require a critical room environment and high lamp power, and the cost remains too high for most normal laboratories. Here we present a novel microfluidics fabrication method utilizing a portable ultraviolet (UV) LED as an alternative UV source for photolithography. With this approach, we can repeat several common microchannels as do these conventional commercial exposure machines, and both the verticality of the channel sidewall and lithography resolution are proved to be acceptable. Further microfluidics applications such as mixing, blood typing and microdroplet generation are implemented to validate the practicability of the chips. This simple but innovative method decreases the cost and requirement of chip fabrication dramatically and may be more popular with ordinary laboratories.

MAGIC: a European program to push the insertion of maskless lithography

NASA Astrophysics Data System (ADS)

Pain, L.; Icard, B.; Tedesco, S.; Kampherbeek, B.; Gross, G.; Klein, C.; Loeschner, H.; Platzgummer, E.; Morgan, R.; Manakli, S.; Kretz, J.; Holhe, C.; Choi, K.-H.; Thrum, F.; Kassel, E.; Pilz, W.; Keil, K.; Butschke, J.; Irmscher, M.; Letzkus, F.; Hudek, P.; Paraskevopoulos, A.; Ramm, P.; Weber, J.

2008-03-01

With the willingness of the semiconductor industry to push manufacturing costs down, the mask less lithography solution represents a promising option to deal with the cost and complexity concerns about the optical lithography solution. Though a real interest, the development of multi beam tools still remains in laboratory environment. In the frame of the seventh European Framework Program (FP7), a new project, MAGIC, started January 1st 2008 with the objective to strengthen the development of the mask less technology. The aim of the program is to develop multi beam systems from MAPPER and IMS nanofabrication technologies and the associated infrastructure for the future tool usage. This paper draws the present status of multi beam lithography and details the content and the objectives of the MAGIC project.

Indus-2 X-ray lithography beamline for X-ray optics and material science applications

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

Dhamgaye, V. P., E-mail: vishal@rrcat.gov.in; Lodha, G. S., E-mail: vishal@rrcat.gov.in

2014-04-24

X-ray lithography is an ideal technique by which high aspect ratio and high spatial resolution micro/nano structures are fabricated using X-rays from synchrotron radiation source. The technique has been used for fabricating optics (X-ray, visible and infrared), sensors and actuators, fluidics and photonics. A beamline for X-ray lithography is operational on Indus-2. The beamline offers wide lithographic window from 1-40keV photon energy and wide beam for producing microstructures in polymers upto size ∼100mm × 100mm. X-ray exposures are possible in air, vacuum and He gas environment. The air based exposures enables the X-ray irradiation of resist for lithography and alsomore » irradiation of biological and liquid samples.« less

Electron-beam lithography for micro and nano-optical applications

NASA Technical Reports Server (NTRS)

Wilson, Daniel W.; Muller, Richard E.; Echternach, Pierre M.

2005-01-01

Direct-write electron-beam lithography has proven to be a powerful technique for fabricating a variety of micro- and nano-optical devices. Binary E-beam lithography is the workhorse technique for fabricating optical devices that require complicated precision nano-scale features. We describe a bi-layer resist system and virtual-mark height measurement for improving the reliability of fabricating binary patterns. Analog E-beam lithography is a newer technique that has found significant application in the fabrication of diffractive optical elements. We describe our techniques for fabricating analog surface-relief profiles in E-beam resist, including some discussion regarding overcoming the problems of resist heating and charging. We also describe a multiple-field-size exposure scheme for suppression of field-stitch induced ghost diffraction orders produced by blazed diffraction gratings on non-flat substrates.

Integrating nanosphere lithography in device fabrication

NASA Astrophysics Data System (ADS)

Laurvick, Tod V.; Coutu, Ronald A.; Lake, Robert A.

2016-03-01

This paper discusses the integration of nanosphere lithography (NSL) with other fabrication techniques, allowing for nano-scaled features to be realized within larger microelectromechanical system (MEMS) based devices. Nanosphere self-patterning methods have been researched for over three decades, but typically not for use as a lithography process. Only recently has progress been made towards integrating many of the best practices from these publications and determining a process that yields large areas of coverage, with repeatability and enabled a process for precise placement of nanospheres relative to other features. Discussed are two of the more common self-patterning methods used in NSL (i.e. spin-coating and dip coating) as well as a more recently conceived variation of dip coating. Recent work has suggested the repeatability of any method depends on a number of variables, so to better understand how these variables affect the process a series of test vessels were developed and fabricated. Commercially available 3-D printing technology was used to incrementally alter the test vessels allowing for each variable to be investigated individually. With these deposition vessels, NSL can now be used in conjunction with other fabrication steps to integrate features otherwise unattainable through current methods, within the overall fabrication process of larger MEMS devices. Patterned regions in 1800 series photoresist with a thickness of ~700nm are used to capture regions of self-assembled nanospheres. These regions are roughly 2-5 microns in width, and are able to control the placement of 500nm polystyrene spheres by controlling where monolayer self-assembly occurs. The resulting combination of photoresist and nanospheres can then be used with traditional deposition or etch methods to utilize these fine scale features in the overall design.

United States Air Force High School Apprenticeship Program. 1990 Program Management Report. Volume 3

DTIC Science & Technology

1991-04-18

User Guide Shelly Knupp 73 Computer-Aided Design (CAD) Area Christopher O’Dell 74 Electron Beam Lithography Suzette Yu 68 Flight Dynamics Laboratory 75...fabrication. I Mr. Ed Davis, for the background knowledge of device processes and I information on electron beam lithography . Captain Mike Cheney, for...researcher may write gates on to the wafer by a process called lithography . This is the most crucial and complex part of the process. Two types of proven

Tunable cw Single-Frequency Source for Injection Seeding 2-micrometer Lasers

DTIC Science & Technology

1990-06-01

Nd:glass Slab Asilomar, CA, January, 1989. Laser for X-ray Lithography ," presented at Lasers 11. R. L. Byer, "Solid State Lasers for Accelerator 89, New...Alumni Association (Stanford Club of M.K. Reed and R.L. Byer, "A Nd:glass Slab Connecticut), April, 1989. Laserfor X-ray Lithography ," to be...and R.L. Byer, "A Nd:Glass Slab asymmetric quantum wells," invited paper QWA1 Laser for Soft X-ray Lithography ", paper MB4, International Quantum

High-resolution nanopatterning of biodegradable polylactide by thermal nanoimprint lithography using gas permeable mold

NASA Astrophysics Data System (ADS)

Takei, Satoshi; Hanabata, Makoto

2017-03-01

We report high-resolution (150 nm) nanopatterning of biodegradable polylactide by thermal nanoimprint lithography using dichloromethane as a volatile solvent for improving the liquidity and a porous cyclodextrin-based gas-permeable mold. This study demonstrates the high-resolution patterning of polylactic acid and other non-liquid functional materials with poor fluidity by thermal nanoimprinting. Such a patterning is expected to expand the utility of thermal nanoimprint lithography and fabricate non-liquid functional materials suitable for eco-friendly and biomedical applications.

Engineering Pre-vascularized Scaffolds for Bone Regeneration.

PubMed

Barabaschi, Giada D G; Manoharan, Vijayan; Li, Qing; Bertassoni, Luiz E

2015-01-01

Survival of functional tissue constructs of clinically relevant size depends on the formation of an organized and uniformly distributed network of blood vessels and capillaries. The lack of such vasculature leads to spatio-temporal gradients in oxygen, nutrients and accumulation of waste products inside engineered tissue constructs resulting in negative biological events at the core of the scaffold. Unavailability of a well-defined vasculature also results in ineffective integration of scaffolds to the host vasculature upon implantation. Arguably, one of the greatest challenges in engineering clinically relevant bone substitutes, therefore, has been the development of vascularized bone scaffolds. Various approaches ranging from peptide and growth factor functionalized biomaterials to hyper-porous scaffolds have been proposed to address this problem with reasonable success. An emerging alternative to address this challenge has been the fabrication of pre-vascularized scaffolds by taking advantage of biomanufacturing techniques, such as soft- and photo-lithography or 3D bioprinting, and cell-based approaches, where functional capillaries are engineered in cell-laden scaffolds prior to implantation. These strategies seek to engineer pre-vascularized tissues in vitro, allowing for improved anastomosis with the host vasculature upon implantation, while also improving cell viability and tissue development in vitro. This book chapter provides an overview of recent methods to engineer pre-vascularized scaffolds for bone regeneration. We first review the development of functional blood capillaries in bony structures and discuss controlled delivery of growth factors, co-culture systems, and on-chip studies to engineer vascularized cell-laden biomaterials. Lastly, we review recent studies using microfabrication techniques and 3D printing to engineer pre-vascularized scaffolds for bone tissue engineering.

PREVAIL-EPL alpha tool electron optics subsystem

NASA Astrophysics Data System (ADS)

Pfeiffer, Hans C.; Dhaliwal, Rajinder S.; Golladay, Steven D.; Doran, Samuel K.; Gordon, Michael S.; Kendall, Rodney A.; Lieberman, Jon E.; Pinckney, David J.; Quickle, Robert J.; Robinson, Christopher F.; Rockrohr, James D.; Stickel, Werner; Tressler, Eileen V.

2001-08-01

The IBM/Nikon alliance is continuing pursuit of an EPL stepper alpha tool based on the PREVAIL technology. This paper provides a status report of the alliance activity with particular focus on the Electron Optical Subsystem developed at IBM. We have previously reported on design features of the PREVAIL alpha system. The new state-of-the-art e-beam lithography concepts have since been reduced to practice and turned into functional building blocks of a production level lithography tool. The electron optical alpha tool subsystem has been designed, build, assembled and tested at IBM's Semiconductor Research and Development Center (SRDC) in East Fishkill, New York. After demonstrating subsystem functionality, the electron optical column and all associated control electronics hardware and software have been shipped during January 2001 to Nikon's facility in Kumagaya, Japan, for integration into the Nikon commercial e-beam stepper alpha tool. Early pre-shipment results obtained with this electron optical subsystem are presented.

Double Emulsion Generation Using a Polydimethylsiloxane (PDMS) Co-axial Flow Focus Device.

PubMed

Cole, Russell H; Tran, Tuan M; Abate, Adam R

2015-12-25

Double emulsions are useful in a number of biological and industrial applications in which it is important to have an aqueous carrier fluid. This paper presents a polydimethylsiloxane (PDMS) microfluidic device capable of generating water/oil/water double emulsions using a coaxial flow focusing geometry that can be fabricated entirely using soft lithography. Similar to emulsion devices using glass capillaries, double emulsions can be formed in channels with uniform wettability and with dimensions much smaller than the channel sizes. Three dimensional flow focusing geometry is achieved by casting a pair of PDMS slabs using two layer soft lithography, then mating the slabs together in a clamshell configuration. Complementary locking features molded into the PDMS slabs enable the accurate registration of features on each of the slab surfaces. Device testing demonstrates formation of double emulsions from 14 µm to 50 µm in diameter while using large channels that are robust against fouling and clogging.

Double Emulsion Generation Using a Polydimethylsiloxane (PDMS) Co-axial Flow Focus Device

PubMed Central

Cole, Russell H.; Tran, Tuan M.; Abate, Adam R.

2015-01-01

Double emulsions are useful in a number of biological and industrial applications in which it is important to have an aqueous carrier fluid. This paper presents a polydimethylsiloxane (PDMS) microfluidic device capable of generating water/oil/water double emulsions using a coaxial flow focusing geometry that can be fabricated entirely using soft lithography. Similar to emulsion devices using glass capillaries, double emulsions can be formed in channels with uniform wettability and with dimensions much smaller than the channel sizes. Three dimensional flow focusing geometry is achieved by casting a pair of PDMS slabs using two layer soft lithography, then mating the slabs together in a clamshell configuration. Complementary locking features molded into the PDMS slabs enable the accurate registration of features on each of the slab surfaces. Device testing demonstrates formation of double emulsions from 14 µm to 50 µm in diameter while using large channels that are robust against fouling and clogging. PMID:26780079

Two-photon equivalent weighting of spatial excimer laser beam profiles

NASA Astrophysics Data System (ADS)

Eva, Eric; Bauer, Harry H.; Metzger, K.; Pfeiffer, A.

2001-04-01

Damage in optical materials for semiconductor lithography applications caused by exposure to 248 or 193 nm light is usually two-photon driven, hence it is a nonlinear function of incident intensity. Materials should be tested with flat- topped temporal and spatial laser beam profiles to facilitate interpretation of data, but in reality this is hard to achieve. Sandstrom provided a formula that approximates any given temporal pulse shape with a two- photon equivalent rectangular pulse (Second Symposium on 193 nm Lithography, Colorado Springs 1997). Known as the integral-square pulse duration, this definition has been embraced as an industry standard. Originally faced with the problem of comparing results obtained with pseudo-Gaussian spatial profiles to literature data, we found that a general solution for arbitrarily inhomogeneous spatial beam profiles exists which results in a definition much similar to Sandstrom's. In addition, we proved the validity of our approach in experiments with intentionally altered beam profiles.

Actinic imaging and evaluation of phase structures on EUV lithography masks

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

Mochi, Iacopo; Goldberg, Kenneth; Huh, Sungmin

2010-09-28

The authors describe the implementation of a phase-retrieval algorithm to reconstruct phase and complex amplitude of structures on EUV lithography masks. Many native defects commonly found on EUV reticles are difficult to detect and review accurately because they have a strong phase component. Understanding the complex amplitude of mask features is essential for predictive modeling of defect printability and defect repair. Besides printing in a stepper, the most accurate way to characterize such defects is with actinic inspection, performed at the design, EUV wavelength. Phase defect and phase structures show a distinct through-focus behavior that enables qualitative evaluation of themore » object phase from two or more high-resolution intensity measurements. For the first time, phase of structures and defects on EUV masks were quantitatively reconstructed based on aerial image measurements, using a modified version of a phase-retrieval algorithm developed to test optical phase shifting reticles.« less

SEMATECH EUVL mask program status

NASA Astrophysics Data System (ADS)

Yun, Henry; Goodwin, Frank; Huh, Sungmin; Orvek, Kevin; Cha, Brian; Rastegar, Abbas; Kearney, Patrick

2009-04-01

As we approach the 22nm half-pitch (hp) technology node, the industry is rapidly running out of patterning options. Of the several lithography techniques highlighted in the International Technology Roadmap for Semiconductors (ITRS), the leading contender for the 22nm hp insertion is extreme ultraviolet lithography (EUVL). Despite recent advances with EUV resist and improvements in source power, achieving defect free EUV mask blank and enabling the EUV mask infrastructure still remain critical issues. To meet the desired EUV high volume manufacturing (HVM) insertion target date of 2013, these obstacles must be resolved on a timely bases. Many of the EUV mask related challenges remain in the pre-competitive stage and a collaborative industry based consortia, such as SEMATECH can play an important role to enable the EUVL landscape. SEMATECH based in Albany, NY is an international consortium representing several of the largest manufacturers in the semiconductor market. Full members include Intel, Samsung, AMD, IBM, Panasonic, HP, TI, UMC, CNSE (College of Nanoscience and Engineering), and Fuller Road Management. Within the SEMATECH lithography division a major thrust is centered on enabling the EUVL ecosystem from mask development, EUV resist development and addressing EUV manufacturability concerns. An important area of focus for the SEMATECH mask program has been the Mask Blank Development Center (MBDC). At the MBDC key issues in EUV blank development such as defect reduction and inspection capabilities are actively pursued together with research partners, key suppliers and member companies. In addition the mask program continues a successful track record of working with the mask community to manage and fund critical mask tools programs. This paper will highlight recent status of mask projects and longer term strategic direction at the MBDC. It is important that mask technology be ready to support pilot line development HVM by 2013. In several areas progress has been made but a continued collaborative effort will be needed along with timely infrastructure investments to meet these challenging goals.

Advancing semiconductor–electrocatalyst systems: application of surface transformation films and nanosphere lithography

DOE PAGES

Brinkert, Katharina; Richter, Matthias H.; Akay, Ömer; ...

2018-01-01

We demonstrate that shadow nanosphere lithography (SNL) is an auspicious tool to systematically create three-dimensional electrocatalyst nanostructures on the semiconductor photoelectrode through controlling their morphology and optical properties.

Applying the miniaturization technologies for biosensor design.

PubMed

Derkus, Burak

2016-05-15

Microengineering technologies give us some opportunities in developing high-tech sensing systems that operate with low volumes of samples, integrates one or more laboratory functions on a single substrate, and enables automation. These millimetric sized devices can be produced for only a few dollars, which makes them promising candidates for mass-production. Besides electron beam lithography, stencil lithography, nano-imprint lithography or dip pen lithography, basic photolithography is the technique which is extensively used for the design of microengineered sensing systems. This technique has some advantages such as easy-to-manufacture, do not require expensive instrumentation, and allow creation of lower micron-sized patterns. In this review, it has been focused on three different type of microengineered sensing devices which are developed using micro/nano-patterning techniques, microfluidic technology, and microelectromechanics system based technology. Copyright © 2016 Elsevier B.V. All rights reserved.

Integration of multiple theories for the simulation of laser interference lithography processes

NASA Astrophysics Data System (ADS)

Lin, Te-Hsun; Yang, Yin-Kuang; Fu, Chien-Chung

2017-11-01

The periodic structure of laser interference lithography (LIL) fabrication is superior to other lithography technologies. In contrast to traditional lithography, LIL has the advantages of being a simple optical system with no mask requirements, low cost, high depth of focus, and large patterning area in a single exposure. Generally, a simulation pattern for the periodic structure is obtained through optical interference prior to its fabrication through LIL. However, the LIL process is complex and combines the fields of optical and polymer materials; thus, a single simulation theory cannot reflect the real situation. Therefore, this research integrates multiple theories, including those of optical interference, standing waves, and photoresist characteristics, to create a mathematical model for the LIL process. The mathematical model can accurately estimate the exposure time and reduce the LIL process duration through trial and error.

16 nm-resolution lithography using ultra-small-gap bowtie apertures

NASA Astrophysics Data System (ADS)

Chen, Yang; Qin, Jin; Chen, Jianfeng; Zhang, Liang; Ma, Chengfu; Chu, Jiaru; Xu, Xianfan; Wang, Liang

2017-02-01

Photolithography has long been a critical technology for nanoscale manufacturing, especially in the semiconductor industry. However, the diffractive nature of light has limited the continuous advance of optical lithography resolution. To overcome this obstacle, near-field scanning optical lithography (NSOL) is an alternative low-cost technique, whose resolution is determined by the near-field localization that can be achieved. Here, we apply the newly-developed backside milling method to fabricate bowtie apertures with a sub-15 nm gap, which can substantially improve the resolution of NSOL. A highly confined electric near field is produced by localized surface plasmon excitation and nanofocusing of the closely-tapered gap. We show contact lithography results with a record 16 nm resolution (FWHM). This photolithography scheme promises potential applications in data storage, high-speed computation, energy harvesting, and other nanotechnology areas.

Integration of multiple theories for the simulation of laser interference lithography processes.

PubMed

Lin, Te-Hsun; Yang, Yin-Kuang; Fu, Chien-Chung

2017-11-24

The periodic structure of laser interference lithography (LIL) fabrication is superior to other lithography technologies. In contrast to traditional lithography, LIL has the advantages of being a simple optical system with no mask requirements, low cost, high depth of focus, and large patterning area in a single exposure. Generally, a simulation pattern for the periodic structure is obtained through optical interference prior to its fabrication through LIL. However, the LIL process is complex and combines the fields of optical and polymer materials; thus, a single simulation theory cannot reflect the real situation. Therefore, this research integrates multiple theories, including those of optical interference, standing waves, and photoresist characteristics, to create a mathematical model for the LIL process. The mathematical model can accurately estimate the exposure time and reduce the LIL process duration through trial and error.

Force-controlled inorganic crystallization lithography.

PubMed

Cheng, Chao-Min; LeDuc, Philip R

2006-09-20

Lithography plays a key role in integrated circuits, optics, information technology, biomedical applications, catalysis, and separation technologies. However, inorganic lithography techniques remain of limited utility for applications outside of the typical foci of integrated circuit manufacturing. In this communication, we have developed a novel stamping method that applies pressure on the upper surface of the stamp to regulate the dewetting process of the inorganic buffer and the evaporation rate of the solvent in this buffer between the substrate and the surface of the stamp. We focused on generating inorganic microstructures with specific locations and also on enabling the ability to pattern gradients during the crystallization of the inorganic salts. This approach utilized a combination of lithography with bottom-up growth and assembly of inorganic crystals. This work has potential applications in a variety of fields, including studying inorganic material patterning and small-scale fabrication technology.

The novel top-coat material for RLS trade-off reduction in EUVL

NASA Astrophysics Data System (ADS)

Onishi, Ryuji; Sakamoto, Rikimaru; Fujitani, Noriaki; Endo, Takafumi; Ho, Bang-ching

2012-03-01

For the next generation lithography (NGL), several technologies have been proposed to achieve the 22nm-node devices and beyond. Extreme ultraviolet (EUV) lithography is one of the candidates for the next generation lithography. In EUV light source development, low power is one of the critical issue because of the low throughput, and another issue is Out of Band (OoB) light existing in EUV light. OoB is concerned to be the cause of deterioration for the lithography performance. In order to avoid this critical issue, we focused on development of the resist top coat material with OoB absorption property as Out of Band Protection Layer (OBPL). We designed this material having high absorbance around 240nm wavelength and high transmittance for EUV light. And this material aimed to improve sensitivity, resolution and LWR performance.

The lithographer's dilemma: shrinking without breaking the bank

NASA Astrophysics Data System (ADS)

Levinson, Harry J.

2013-10-01

It can no longer be assumed that the lithographic scaling which has previously driven Moore's Law will lead in the future to reduced cost per transistor. Until recently, higher prices for lithography tools were offset by improvements in scanner productivity. The necessity of using double patterning to extend scaling beyond the single exposure resolution limit of optical lithography has resulted in a sharp increase in the cost of patterning a critical construction layer that has not been offset by improvements in exposure tool productivity. Double patterning has also substantially increased the cost of mask sets. EUV lithography represents a single patterning option, but the combination of very high exposure tools prices, moderate throughput, high maintenance costs, and expensive mask blanks makes this a solution more expensive than optical double patterning but less expensive than triple patterning. Directed self-assembly (DSA) could potentially improve wafer costs, but this technology currently is immature. There are also design layout and process integration issues associated with DSA that need to be solved in order to obtain full benefit from tighter pitches. There are many approaches for improving the cost effectiveness of lithography. Innovative double patterning schemes lead to smaller die. EUV lithography productivity can be improved with higher power light sources and improved reliability. There are many technical and business challenges for extending EUV lithography to higher numerical apertures. Efficient contact hole and cut mask solutions are needed, as well as very tight overlay control, regardless of lithographic solution.

Line edge roughness (LER) mitigation studies specific to interference-like lithography

NASA Astrophysics Data System (ADS)

Baylav, Burak; Estroff, Andrew; Xie, Peng; Smith, Bruce W.

2013-04-01

Line edge roughness (LER) is a common problem to most lithography approaches and is seen as the main resolution limiter for advanced technology nodes1. There are several contributors to LER such as chemical/optical shot noise, random nature of acid diffusion, development process, and concentration of acid generator/base quencher. Since interference-like lithography (IL) is used to define one directional gridded patterns, some LER mitigation approaches specific to IL-like imaging can be explored. Two methods investigated in this work for this goal are (i) translational image averaging along the line direction and (ii) pupil plane filtering. Experiments regarding the former were performed on both interferometric and projection lithography systems. Projection lithography experiments showed a small amount of reduction in low/mid frequency LER value for image averaged cases at pitch of 150 nm (193 nm illumination, 0.93 NA) with less change for smaller pitches. Aerial image smearing did not significantly increase LER since it was directional. Simulation showed less than 1% reduction in NILS (compared to a static, smooth mask equivalent) with ideal alignment. In addition, description of pupil plane filtering on the transfer of mask roughness is given. When astigmatism-like aberrations were introduced in the pupil, transfer of mask roughness is decreased at best focus. It is important to exclude main diffraction orders from the filtering to prevent contrast and NILS loss. These ideas can be valuable as projection lithography approaches to conditions similar to IL (e.g. strong RET methods).

Layered Manufacturing of Dental Ceramics: Fracture Mechanics, Microstructure, and Elemental Composition of Lithography-Sintered Ceramic.

PubMed

Uçar, Yurdanur; Aysan Meriç, İpek; Ekren, Orhun

2018-02-11

To compare the fracture mechanics, microstructure, and elemental composition of lithography-based ceramic manufacturing with pressing and CAD/CAM. Disc-shaped specimens (16 mm diameter, 1.2 mm thick) were used for mechanical testing (n = 10/group). Biaxial flexural strength of three groups (In-Ceram alumina [ICA], lithography-based alumina, ZirkonZahn) were determined using the "piston on 3-ball" technique as suggested in test Standard ISO-6872. Vickers hardness test was performed. Fracture toughness was calculated using fractography. Results were statistically analyzed using Kruskal-Wallis test followed by Dunnett T3 (α = 0.05). Weibull analysis was conducted. Polished and fracture surface characterization was made using scanning electron microscope (SEM). Energy dispersive spectroscopy (EDS) was used for elemental analysis. Biaxial flexural strength of ICA, LCM alumina (LCMA), and ZirkonZahn were 147 ± 43 MPa, 490 ± 44 MPa, and 709 ± 94 MPa, respectively, and were statistically different (P ≤ 0.05). The Vickers hardness number of ICA was 850 ± 41, whereas hardness values for LCMA and ZirkonZahn were 1581 ± 144 and 1249 ± 57, respectively, and were statistically different (P ≤ 0.05). A statistically significant difference was found between fracture toughness of ICA (2 ± 0.4 MPa⋅m 1/2 ), LCMA (6.5 ± 1.5 MPa⋅m 1/2 ), and ZirkonZahn (7.7 ± 1 MPa⋅m 1/2 ) (P ≤ 0.05). Weibull modulus was highest for LCMA (m = 11.43) followed by ZirkonZahn (m = 8.16) and ICA (m = 5.21). Unlike LCMA and ZirkonZahn groups, a homogeneous microstructure was not observed for ICA. EDS results supported the SEM images. Within the limitations of this in vitro study, it can be concluded that LCM seems to be a promising technique for final ceramic object manufacturing in dental applications. Both the manufacturing method and the material used should be improved. © 2018 by the American College of Prosthodontists.

Ultra-short wavelength x-ray system

DOEpatents

Umstadter, Donald [Ann Arbor, MI; He, Fei [Ann Arbor, MI; Lau, Yue-Ying [Potomac, MD

2008-01-22

A method and apparatus to generate a beam of coherent light including x-rays or XUV by colliding a high-intensity laser pulse with an electron beam that is accelerated by a synchronized laser pulse. Applications include x-ray and EUV lithography, protein structural analysis, plasma diagnostics, x-ray diffraction, crack analysis, non-destructive testing, surface science and ultrafast science.

Fabrication of Pt nanowires with a diffraction-unlimited feature size by high-threshold lithography

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

Li, Li, E-mail: lil@cust.edu.cn, E-mail: wangz@cust.edu.cn, E-mail: kq-peng@bnu.edu.cn; Zhang, Ziang; Yu, Miao

2015-09-28

Although the nanoscale world can already be observed at a diffraction-unlimited resolution using far-field optical microscopy, to make the step from microscopy to lithography still requires a suitable photoresist material system. In this letter, we consider the threshold to be a region with a width characterized by the extreme feature size obtained using a Gaussian beam spot. By narrowing such a region through improvement of the threshold sensitization to intensity in a high-threshold material system, the minimal feature size becomes smaller. By using platinum as the negative photoresist, we demonstrate that high-threshold lithography can be used to fabricate nanowire arraysmore » with a scalable resolution along the axial direction of the linewidth from the micro- to the nanoscale using a nanosecond-pulsed laser source with a wavelength λ{sub 0} = 1064 nm. The minimal feature size is only several nanometers (sub λ{sub 0}/100). Compared with conventional polymer resist lithography, the advantages of high-threshold lithography are sharper pinpoints of laser intensity triggering the threshold response and also higher robustness allowing for large area exposure by a less-expensive nanosecond-pulsed laser.« less

Fabrication of nanoporous membranes for tuning microbial interactions and biochemical reactions

DOE PAGES

Shankles, Peter G.; Timm, Andrea C.; Doktycz, Mitchel J.; ...

2015-10-21

Here we describe how new strategies for combining conventional photo- and soft- lithographic techniques with high-resolution patterning and etching strategies are needed in order to produce multi-scale fluidic platforms that address the full range of functional scales seen in complex biological and chemical systems. The smallest resolution required for an application often dictates the fabrication method used. Micromachining and micro-powder blasting yield higher throughput, but lack the resolution needed to fully address biological and chemical systems at the cellular and molecular scales. In contrast, techniques such as electron beam lithography or nanoimprinting allow nanoscale resolution, but are traditionally considered costlymore » and slow. Other techniques such as photolithography or soft lithography have characteristics between these extremes. Combining these techniques to fabricate multi-scale or hybrid fluidics allows fundamental biological and chemical questions can be answered. In this study, a combination of photolithography and electron beam lithography are used to produce two multi-scale fluidic devices that incorporate porous membranes into complex fluidic networks to control the flow of energy, information, and materials in chemical form. In the first device, materials and energy were used to support chemical reactions. A nanoporous membrane fabricated with e-beam lithography separates two parallel, serpentine channels. Photolithography was used to write microfluidic channels around the membrane. The pores were written at 150nm and reduced in size with silicon dioxide deposition from plasma enhanced chemical vapor deposition (PECVD) and atomic layer deposition (ALD). Using this method, the molecular weight cutoff (MWCO) of the membrane can be adapted to the system of interest. In the second approach, photolithography was used to fabricate 200nm thin pores. The pores confined microbes and allowed energy replenishment from a media perfusion channel. The same device can be used for study of intercellular communication via the secretion and uptake of signal molecules. Pore size was tested with 750nm fluorescent polystyrene beads and fluorescein dye. The 200nm PDMS pores were shown to be robust enough to hold 750nm beads while under pressure, but allow fluorescein to diffuse across the barrier. Further testing showed that extended culture of bacteria within the chambers was possible. Finally, these two examples show how lithographically defined porous membranes can be adapted to two unique situations and used to tune the flow of chemical energy, materials, and information within a microfluidic network.« less

Advanced scanning probe lithography.

PubMed

Garcia, Ricardo; Knoll, Armin W; Riedo, Elisa

2014-08-01

The nanoscale control afforded by scanning probe microscopes has prompted the development of a wide variety of scanning-probe-based patterning methods. Some of these methods have demonstrated a high degree of robustness and patterning capabilities that are unmatched by other lithographic techniques. However, the limited throughput of scanning probe lithography has prevented its exploitation in technological applications. Here, we review the fundamentals of scanning probe lithography and its use in materials science and nanotechnology. We focus on robust methods, such as those based on thermal effects, chemical reactions and voltage-induced processes, that demonstrate a potential for applications.

Optimization of RET flow using test layout

NASA Astrophysics Data System (ADS)

Zhang, Yunqiang; Sethi, Satyendra; Lucas, Kevin

2008-11-01

At advanced technology nodes with extremely low k1 lithography, it is very hard to achieve image fidelity requirements and process window for some layout configurations. Quite often these layouts are within simple design rule constraints for a given technology node. It is important to have these layouts included during early RET flow development. Most of RET developments are based on shrunk layout from the previous technology node, which is possibly not good enough. A better methodology in creating test layout is required for optical proximity correction (OPC) recipe and assists feature development. In this paper we demonstrate the application of programmable test layouts in RET development. Layout pattern libraries are developed and embedded in a layout tool (ICWB). Assessment gauges are generated together with patterns for quick correction accuracy assessment. Several groups of test pattern libraries have been developed based on learning from product patterns and a layout DOE approach. The interaction between layout patterns and OPC recipe has been studied. Correction of a contact layer is quite challenge because of poor convergence and low process window. We developed test pattern library with many different contact configurations. Different OPC schemes are studied on these test layouts. The worst process window patterns are pinpointed for a given illumination condition. Assist features (AF) are frequently placed according to pre-determined rules to improve lithography process window. These rules are usually derived from lithographic models and experiments. Direct validation of AF rules is required at development phase. We use the test layout approach to determine rules in order to eliminate AF printability problem.

EDITORIAL: Nanotechnology impact on sensors Nanotechnology impact on sensors

NASA Astrophysics Data System (ADS)

Brugger, Jürgen

2009-10-01

A sensor is a device that responds to a stimulus by generating a functional output induced by a change in some intrinsic properties. We are surrounded by sensors and sensing networks that monitor a multitude of parameters in view of enhancing our safety and quality of life. Sensors assist us in health care and diagnostics, they monitor our environment, our aeroplanes and automobiles, our mobile phones, game consoles and watches, and last but not least, many of our human body functions. Modern sensing systems have greatly benefited in recent decades from advances in microelectronics and microengineering, mainly in view of making sensors smaller, cheaper, more sensitive, more selective, and with a better signal-to-noise ratio, following classical scaling rules. So how about nanotechnology-enabled sensing? Nanoscale features have a great impact on many (though not all) sensing systems, in particular where the surface-to-volume ratio plays a fundamental role, such as in certain chemical and gas sensors. The high surface-to-volume ratios of nanoporous and nanostructured materials have led to their implementation in sensing systems since sensing research first began to engage with the nanotechnology. The surface plasmon resonances of nanostructures have also enriched the scope for developing novel sensing devices. On the other hand, sensors where bulk properties dominate, such as inertial sensors, are less likely to benefit from extreme scaling. Advances in thin film techniques and chemical synthesis have allowed material properties to be tailored to sensing requirements for enhanced performance. These bottom-up fabrication techniques enable parallel fabrication of ordered nanostructures, often in domain-like areas with molecular precision. At the same time the progress in top-down methods such as scanning probe lithography, nanoimprint lithography, soft-lithography and stencil lithography have also facilitated research into sensing and actuating nanotechnology. Although radically different from each other, these techniques represent a formidable toolset for structuring materials at the nanoscale in a multitude of fashions. The availability of these new nanopatterning techniques are increasingly implemented in the manufacturing of advanced sensor systems, and we can expect in the next decade an increased emergence of micro- and nanosensor systems that implement novel nano-functionalities thanks to cost-effective fabrication. Moreover, some of these techniques are desktop tools that can be used on your kitchen table at home. Thus, over the past 20 years we have witnessed a democratization of nanotechnology. More and more researchers, engineers, and even schoolchildren, can benefit from and use these new methods and devise novel applications for nanosystems. This is certainly beneficial to expediting a further dramatic increase in knowledge and the development of actual devices and applications that put gains in our understanding of nanosystems into practice. Nanotechnology is a relatively young discipline compared to classical engineering, and it is inherently interdisciplinary. It seems that in many fields we are actually just beginning to venture into these new dimensions. Challenges remain, however, in all aspects of nanotechnology. We need to improve imaging performance by enabling faster (video rate) coverage of larger surfaces, eventually down to the molecular scale. We also need to perfect nanopatterning methods to improve resolution, overlay and throughput capabilities. Future nanomanufacturing will most likely rely on combinations of top-down engineering and bottom-up self-assembly. Last but not least, we need to find ways for the mutual integration of multiple length-scale devices (nano/micro/macro) so that we can program a 'nano-functionality' into a microsystem exactly where it is needed. Such improvements will ultimately lead to improved sensors and contribute not only to improvements in our quality of life but also to building energy-saving systems that can be fabricated with low-waste manufacturing methods.

Development of nanoimprint lithography templates for the contact hole layer application (Conference Presentation)

NASA Astrophysics Data System (ADS)

Ichimura, Koji; Hikichi, Ryugo; Harada, Saburo; Kanno, Koichi; Kurihara, Masaaki; Hayashi, Naoya

2017-04-01

Nanoimprint lithography, NIL, is gathering much attention as one of the most potential candidates for the next generation lithography for semiconductor. This technology needs no pattern data modification for exposure, simpler exposure system, and single step patterning process without any coat/develop truck, and has potential of cost effective patterning rather than very complex optical lithography and/or EUV lithography. NIL working templates are made by the replication of the EB written high quality master templates. Fabrication of high resolution master templates is one of the most important issues. Since NIL is 1:1 pattern transfer process, master templates have 4 times higher resolution compared with photomasks. Another key is to maintain the quality of the master templates in replication process. NIL process is applied for the template replication and this imprint process determines most of the performance of the replicated templates. Expectations to the NIL are not only high resolution line and spaces but also the contact hole layer application. Conventional ArF-i lithography has a certain limit in size and pitch for contact hole fabrication. On the other hand, NIL has good pattern fidelity for contact hole fabrication at smaller sizes and pitches compared with conventional optical lithography. Regarding the tone of the templates for contact hole, there are the possibilities of both tone, the hole template and the pillar template, depending on the processes of the wafer side. We have succeeded to fabricate both types of templates at 2xnm in size. In this presentation, we will be discussing fabrication or our replica template for the contact hole layer application. Both tone of the template fabrication will be presented as well as the performance of the replica templates. We will also discuss the resolution improvement of the hole master templates by using various e-beam exposure technologies.

Fabricating Blazed Diffraction Gratings by X-Ray Lithography

NASA Technical Reports Server (NTRS)

Mouroulis, Pantazis; Hartley, Frank; Wilson, Daniel

2004-01-01

Gray-scale x-ray lithography is undergoing development as a technique for fabricating blazed diffraction gratings. As such, gray-scale x-ray lithography now complements such other grating-fabrication techniques as mechanical ruling, holography, ion etching, laser ablation, laser writing, and electron-beam lithography. Each of these techniques offers advantages and disadvantages for implementing specific grating designs; no single one of these techniques can satisfy the design requirements for all applications. Gray-scale x-ray lithography is expected to be advantageous for making gratings on steeper substrates than those that can be made by electron-beam lithography. This technique is not limited to sawtooth groove profiles and flat substrates: various groove profiles can be generated on arbitrarily shaped (including highly curved) substrates with the same ease as sawtooth profiles can be generated on flat substrates. Moreover, the gratings fabricated by this technique can be made free of ghosts (spurious diffraction components attributable to small spurious periodicities in the locations of grooves). The first step in gray-scale x-ray lithography is to conformally coat a substrate with a suitable photoresist. An x-ray mask (see Figure 1) is generated, placed between the substrate and a source of collimated x-rays, and scanned over the substrate so as to create a spatial modulation in the exposure of the photoresist. Development of the exposed photoresist results in a surface corrugation that corresponds to the spatial modulation and that defines the grating surface. The grating pattern is generated by scanning an appropriately shaped x-ray area mask along the substrate. The mask example of Figure 1 would generate a blazed grating profile when scanned in the perpendicular direction at constant speed, assuming the photoresist responds linearly to incident radiation. If the resist response is nonlinear, then the mask shape can be modified to account for the nonlinearity and produce a desired groove profile. An example of grating grooves generated by this technique is shown in Figure 2. A maximum relative efficiency of 88 percent has been demonstrated.

75 FR 81643 - In the Matter of Certain Semiconductor Products Made by Advanced Lithography Techniques and...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-28

... Semiconductor Products Made by Advanced Lithography Techniques and Products Containing Same; Notice of... Mexico) (``STC''), alleging a violation of section 337 in the importation, sale for [[Page 81644

Farbrication of diffractive optical elements on a Si chip by an imprint lithography using nonsymmetrical silicon mold

NASA Astrophysics Data System (ADS)

Hirai, Yoshihiko; Okano, Masato; Okuno, Takayuki; Toyota, Hiroshi; Yotsuya, Tsutomu; Kikuta, Hisao; Tanaka, Yoshio

2001-11-01

Fabrication of a fine diffractive optical element on a Si chip is demonstrated using imprint lithography. A chirped diffraction grating, which has modulated pitched pattern with curved cross section is fabricated by an electron beam lithography, where the exposure dose profile is automatically optimized by computer aided system. Using the resist pattern as an etching mask, anisotropic dry etching is performed to transfer the resist pattern profile to the Si chip. The etched Si substrate is used as a mold in the imprint lithography. The Si mold is pressed to a thin polymer (poly methyl methacrylate) on a Si chip. After releasing the mold, a fine diffractive optical pattern is successfully transferred to the thin polymer. This method is exceedingly useful for fabrication of integrated diffractive optical elements with electric circuits on a Si chip.

High throughput optical lithography by scanning a massive array of bowtie aperture antennas at near-field

PubMed Central

Wen, X.; Datta, A.; Traverso, L. M.; Pan, L.; Xu, X.; Moon, E. E.

2015-01-01

Optical lithography, the enabling process for defining features, has been widely used in semiconductor industry and many other nanotechnology applications. Advances of nanotechnology require developments of high-throughput optical lithography capabilities to overcome the optical diffraction limit and meet the ever-decreasing device dimensions. We report our recent experimental advancements to scale up diffraction unlimited optical lithography in a massive scale using the near field nanolithography capabilities of bowtie apertures. A record number of near-field optical elements, an array of 1,024 bowtie antenna apertures, are simultaneously employed to generate a large number of patterns by carefully controlling their working distances over the entire array using an optical gap metrology system. Our experimental results reiterated the ability of using massively-parallel near-field devices to achieve high-throughput optical nanolithography, which can be promising for many important nanotechnology applications such as computation, data storage, communication, and energy. PMID:26525906

EUV lithography using water-developable resist material derived from biomass

NASA Astrophysics Data System (ADS)

Takei, Satoshi; Oshima, Akihiro; Oyama, Tomoko G.; Ichikawa, Takumi; Sekiguchi, Atsushi; Kashiwakura, Miki; Kozawa, Takahiro; Tagawa, Seiichi

2013-03-01

A water-developable resist material which had specific desired properties such as high sensitivity of 5.0 μC/cm2, thermal stability of 160 °C, suitable calculated linear absorption coefficients of 13.5 nm, and acceptable CF4 etch selectivity was proposed using EB lithography for EUV lithography. A water developable resist material derived from biomass is expected for non-petroleum resources, environmental affair, safety, easiness of handling, and health of the working people, instead of the common developable process of trimethylphenylammonium hydroxide. 100 nm line and 400 nm space patterning images with exposure dose of 5.0 μC/cm2 were provided by specific process conditions of EB lithography. The developed trehalose derivatives with hydroxyl groups and EB sensitive groups in the water-developable resist material derived from biomass were applicable to future development of high-sensitive and resolution negative type of water-developable resist material as a novel chemical design.

High-sensitivity green resist material with organic solvent-free spin-coating and tetramethylammonium hydroxide-free water-developable processes for EB and EUV lithography

NASA Astrophysics Data System (ADS)

Takei, Satoshi; Hanabata, Makoto; Oshima, Akihiro; Kashiwakura, Miki; Kozawa, Takahiro; Tagawa, Seiichi

2015-03-01

We investigated the eco-friendly electron beam (EB) and extreme-ultraviolet (EUV) lithography using a high-sensitive negative type of green resist material derived from biomass to take advantage of organic solvent-free water spin-coating and tetramethylammonium hydroxide(TMAH)-free water-developable techniques. A water developable, non-chemically amplified, high sensitive, and negative tone resist material in EB lithography was developed for environmental affair, safety, easiness of handling, and health of the working people, instead of the common developable process of TMAH. The material design concept to use the water-soluble resist material with acceptable properties such as pillar patterns with less than 100 nm in high EB sensitivity of 10 μC/cm2 and etch selectivity with a silicon-based middle layer in CF4 plasma treatment was demonstrated for EB and EUV lithography.

Extension of optical lithography by mask-litho integration with computational lithography

NASA Astrophysics Data System (ADS)

Takigawa, T.; Gronlund, K.; Wiley, J.

2010-05-01

Wafer lithography process windows can be enlarged by using source mask co-optimization (SMO). Recently, SMO including freeform wafer scanner illumination sources has been developed. Freeform sources are generated by a programmable illumination system using a micro-mirror array or by custom Diffractive Optical Elements (DOE). The combination of freeform sources and complex masks generated by SMO show increased wafer lithography process window and reduced MEEF. Full-chip mask optimization using source optimized by SMO can generate complex masks with small variable feature size sub-resolution assist features (SRAF). These complex masks create challenges for accurate mask pattern writing and low false-defect inspection. The accuracy of the small variable-sized mask SRAF patterns is degraded by short range mask process proximity effects. To address the accuracy needed for these complex masks, we developed a highly accurate mask process correction (MPC) capability. It is also difficult to achieve low false-defect inspections of complex masks with conventional mask defect inspection systems. A printability check system, Mask Lithography Manufacturability Check (M-LMC), is developed and integrated with 199-nm high NA inspection system, NPI. M-LMC successfully identifies printable defects from all of the masses of raw defect images collected during the inspection of a complex mask. Long range mask CD uniformity errors are compensated by scanner dose control. A mask CD uniformity error map obtained by mask metrology system is used as input data to the scanner. Using this method, wafer CD uniformity is improved. As reviewed above, mask-litho integration technology with computational lithography is becoming increasingly important.

Novel EUV photoresist for sub-7nm node (Conference Presentation)

NASA Astrophysics Data System (ADS)

Furukawa, Tsuyoshi; Naruoka, Takehiko; Nakagawa, Hisashi; Miyata, Hiromu; Shiratani, Motohiro; Hori, Masafumi; Dei, Satoshi; Ayothi, Ramakrishnan; Hishiro, Yoshi; Nagai, Tomoki

2017-04-01

Extreme ultraviolet (EUV) lithography has been recognized as a promising candidate for the manufacturing of semiconductor devices as LS and CH pattern for 7nm node and beyond. EUV lithography is ready for high volume manufacturing stage. For the high volume manufacturing of semiconductor devices, significant improvement of sensitivity and line edge roughness (LWR) and Local CD Uniformity (LCDU) is required for EUV resist. It is well-known that the key challenge for EUV resist is the simultaneous requirement of ultrahigh resolution (R), low line edge roughness (L) and high sensitivity (S). Especially high sensitivity and good roughness is important for EUV lithography high volume manufacturing. We are trying to improve sensitivity and LWR/LCDU from many directions. From material side, we found that both sensitivity and LWR/LCDU are simultaneously improved by controlling acid diffusion length and efficiency of acid generation using novel resin and PAG. And optimizing EUV integration is one of the good solution to improve sensitivity and LWR/LCDU. We are challenging to develop new multi-layer materials to improve sensitivity and LWR/LCDU. Our new multi-layer materials are designed for best performance in EUV lithography system. From process side, we found that sensitivity was substantially improved maintaining LWR applying novel type of chemical amplified resist (CAR) and process. EUV lithography evaluation results obtained for new CAR EUV interference lithography. And also metal containing resist is one possibility to break through sensitivity and LWR trade off. In this paper, we will report the recent progress of sensitivity and LWR/LCDU improvement of JSR novel EUV resist and process.

Engineering an in vitro organotypic model for studying cardiac hypertrophy.

PubMed

Jain, Aditi; Hasan, Jafar; Desingu, Perumal Arumugam; Sundaresan, Nagalingam R; Chatterjee, Kaushik

2018-05-01

Neonatal cardiomyocytes cultured on flat surfaces are commonly used as a model to study cardiac failure of diverse origin. A major drawback of such a system is that the cardiomyocytes do not exhibit alignment, organization and calcium transients, similar to the native heart. Therefore, there is a need to develop in vitro platforms that recapitulate the cellular microenvironment of the murine heart as organotypic models to study cardiovascular diseases. In this study, we report an engineered platform that mimics cardiac cell organization and function of the heart. For this purpose, microscale ridges were fabricated on silicon using ultraviolet lithography and reactive ion etching techniques. Physical characterization of the microstructures was done using scanning electron microscopy and atomic force microscopy. Cardiomyocytes grown on these micro-ridges showed global parallel alignment and elliptical nuclear morphology as observed in the heart. Interestingly, calcium currents traversed the engineered cardiomyocytes in a coordinated and directional manner. Moreover, the cardiomyocytes on the engineered substrates were found to be responsive to hypertrophic stimuli, as observed by the expression of a fetal gene, atrial natriuretic peptide and increase in calcium transients upon agonist treatment. Taken together, our work demonstrates that micro-ridges can be used to obtain cardiomyocyte response in vitro, which closely resembles mammalian heart. Copyright © 2018 Elsevier B.V. All rights reserved.

Report of the workshop on transferring X-ray Lithography Synchrotron (XLS) technology to industry

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

Marcuse, W.

1987-01-01

This paper reports on plans to develop an x-ray synchrotron for use in lithography. The primary concern of the present paper is technology transfer from national laboratories to private industry. (JDH)

Microfabrication and Test of a Three-Dimensional Polymer Hydro-focusing Unit for Flow Cytometry Applications

NASA Technical Reports Server (NTRS)

Yang, Ren; Feeback, Daniel L.; Wang, Wanjun

2004-01-01

This paper details a novel three-dimensional (3D) hydro-focusing micro cell sorter for micro flow cytometry applications. The unit was microfabricated by means of SU-8 3D lithography. The 3D microstructure for coaxial sheathing was designed, microfabricated, and tested. Three-dimensional hydro-focusing capability was demonstrated with an experiment to sort labeled tanned sheep erythrocytes (red blood cells). This polymer hydro-focusing microstructure is easily microfabricated and integrated with other polymer microfluidic structures.

Microfabrication and Test of a Three-Dimensional Polymer Hydro-Focusing Unit for Flow Cytometry Applications

NASA Technical Reports Server (NTRS)

Yang, Ren; Feedback, Daniel L.; Wang, Wanjun

2004-01-01

This paper details a novel three-dimensional (3D) hydro-focusing micro cell sorter for micro flow cytometry applications. The unit was micro-fabricated by means of SU-8 3D lithography. The 3D microstructure for coaxial sheathing was designed, micro-fabricated, and tested. Three-dimensional hydrofocusing capability was demonstrated with an experiment to sort labeled tanned sheep erythrocytes (red blood cells). This polymer hydro-focusing microstructure is easily micro-fabricated and integrated with other polymer microfluidic structures.

Micro to Nanoscale Engineering of Surface Precipitates Using Reconfigurable Contact Lines.

PubMed

Kabi, Prasenjit; Chaudhuri, Swetaprovo; Basu, Saptarshi

2018-02-06

Nanoscale engineering has traditionally adopted the chemical route of synthesis or optochemical techniques such as lithography requiring large process times, expensive equipment, and an inert environment. Directed self-assembly using evaporation of nanocolloidal droplet can be a potential low-cost alternative across various industries ranging from semiconductors to biomedical systems. It is relatively simple to scale and reorient the evaporation-driven internal flow field in an evaporating droplet which can direct dispersed matter into functional agglomerates. The resulting functional precipitates not only exhibit macroscopically discernible changes but also nanoscopic variations in the particulate assembly. Thus, the evaporating droplet forms an autonomous system for nanoscale engineering without the need for external resources. In this article, an indigenous technique of interfacial re-engineering, which is both simple and inexpensive to implement, is developed. Such re-engineering widens the horizon for surface patterning previously limited by the fixed nature of the droplet interface. It involves handprinting hydrophobic lines on a hydrophilic substrate to form a confinement of any selected geometry using a simple document stamp. Droplets cast into such confinements get modulated into a variety of shapes. The droplet shapes control the contact line behavior, evaporation dynamics, and complex internal flow pattern. By exploiting the dynamic interplay among these variables, we could control the deposit's macro- as well as nanoscale assembly not possible with simple circular droplets. We provide a detailed mechanism of the coupling at various length scales enabling a predictive capability in custom engineering, particularly useful in nanoscale applications such as photonic crystals.

Sub-half-micron contact window design with 3D photolithography simulator

NASA Astrophysics Data System (ADS)

Brainerd, Steve K.; Bernard, Douglas A.; Rey, Juan C.; Li, Jiangwei; Granik, Yuri; Boksha, Victor V.

1997-07-01

In state of the art IC design and manufacturing certain lithography layers have unique requirements. Latitudes and tolerances that apply to contacts and polysilicon gates are tight for such critical layers. Industry experts are discussing the most cost effective ways to use feature- oriented equipment and materials already developed for these layers. Such requirements introduce new dimensions into the traditionally challenging task for the photolithography engineer when considering various combinations of multiple factors to optimize and control the process. In addition, he/she faces a rapidly increasing cost of experiments, limited time and scarce access to equipment to conduct them. All the reasons presented above support simulation as an ideal method to satisfy these demands. However lithography engineers may be easily dissatisfied with a simulation tool when discovering disagreement between the simulation and experimental data. The problem is that several parameters used in photolithography simulation are very process specific. Calibration, i.e. matching experimental and simulation data using a specific set of procedures allows one to effectively use the simulation tool. We present results of a simulation based approach to optimize photolithography processes for sub-0.5 micron contact windows. Our approach consists of: (1) 3D simulation to explore different lithographic options, (2) calibration to a range of process conditions with extensive use of specifically developed optimization techniques. The choice of a 3D simulator is essential because of 3D nature of the problem of contact window design. We use DEPICT 4.1. This program performs fast aerial image simulation as presented before. For 3D exposure the program uses an extension to three-dimensions of the high numerical aperture model combined with Fast Fourier Transforms for maximum performance and accuracy. We use Kim (U.C. Berkeley) model and the fast marching Level Set method respectively for the calculation of resist development rates and resist surface movement during development process. Calibration efforts were aimed at matching experimental results on contact windows obtained after exposure of a binary mask. Additionally, simulation was applied to conduct quantitative analysis of PSM design capabilities, optical proximity correction, and stepper parameter optimization. Extensive experiments covered exposure (ASML 5500/100D stepper), pre- and post-exposure bake and development (2.38% TMAH, puddle process) of JSR IX725D2G and TOK iP3500 photoresists films on 200 mm test wafers. `Aquatar' was used as top antireflective coating, SEM pictures of developed patterns were analyzed and compared with simulation results for different values of defocus, exposure energies, numerical aperture and partial coherence.

SEM contour based metrology for microlens process studies in CMOS image sensor technologies

NASA Astrophysics Data System (ADS)

Lakcher, Amine; Ostrovsky, Alain; Le-Gratiet, Bertrand; Berthier, Ludovic; Bidault, Laurent; Ducoté, Julien; Jamin-Mornet, Clémence; Mortini, Etienne; Besacier, Maxime

2018-03-01

From the first digital cameras which appeared during the 70s to cameras of current smartphones, image sensors have undergone significant technological development in the last decades. The development of CMOS image sensor technologies in the 90s has been the main driver of the recent progresses. The main component of an image sensor is the pixel. A pixel contains a photodiode connected to transistors but only the photodiode area is light sensitive. This results in a significant loss of efficiency. To solve this issue, microlenses are used to focus the incident light on the photodiode. A microlens array is made out of a transparent material and has a spherical cap shape. To obtain this spherical shape, a lithography process is performed to generate resist blocks which are then annealed above their glass transition temperature (reflow). Even if the dimensions to consider are higher than in advanced IC nodes, microlenses are sensitive to process variability during lithography and reflow. A good control of the microlens dimensions is key to optimize the process and thus the performance of the final product. The purpose of this paper is to apply SEM contour metrology [1, 2, 3, 4] to microlenses in order to develop a relevant monitoring methodology and to propose new metrics to engineers to evaluate their process or optimize the design of the microlens arrays.

Photosensitive naturally derived resins toward optical 3-D printing

NASA Astrophysics Data System (ADS)

Skliutas, Edvinas; Kasetaite, Sigita; Jonušauskas, Linas; Ostrauskaite, Jolita; Malinauskas, Mangirdas

2018-04-01

Recent advances in material engineering have shown that renewable raw materials, such as plant oils or glycerol, can be applied for synthesis of polymers due to ready availability, inherent biodegradability, limited toxicity, and existence of modifiable functional groups and eventually resulting to a potentially lower cost. After additional chemical modifications (epoxidation, acrylation, double bonds metathesis, etc.), they can be applied in such high-tech areas as stereolithography, which allows fabrication of three-dimensional (3-D) objects. "Autodesk's" 3-D optical printer "Ember" using 405-nm light was implemented for dynamic projection lithography. It enabled straightforward spatio-selective photopolymerization on demand, which allows development of various photosensitive materials. The bio-based resins' photosensitivity was compared to standard "Autodesk" "PR48" and "Formlabs" "Clear" materials. It turned out that the bioresins need a higher energy dose to be cured (a least 16 J · cm - 2 for a single layer varying from 100 to 130 μm). Despite this, submillimeter range 2.5-D structural features were formed, and their morphology was assessed by optical profilometer and scanning electron microscope. It was revealed that a higher exposition dose (up to 26 J · cm - 2) results in a linear increase in the formed structures height, proving controllability of the undergoing process. Overall, the provided results show that naturally derived resins are suitable candidates for tabletop gray-tone lithography.

Improving 130nm node patterning using inverse lithography techniques for an analog process

NASA Astrophysics Data System (ADS)

Duan, Can; Jessen, Scott; Ziger, David; Watanabe, Mizuki; Prins, Steve; Ho, Chi-Chien; Shu, Jing

2018-03-01

Developing a new lithographic process routinely involves usage of lithographic toolsets and much engineering time to perform data analysis. Process transfers between fabs occur quite often. One of the key assumptions made is that lithographic settings are equivalent from one fab to another and that the transfer is fluid. In some cases, that is far from the truth. Differences in tools can change the proximity effect seen in low k1 imaging processes. If you use model based optical proximity correction (MBOPC), then a model built in one fab will not work under the same conditions at another fab. This results in many wafers being patterned to try and match a baseline response. Even if matching is achieved, there is no guarantee that optimal lithographic responses are met. In this paper, we discuss the approach used to transfer and develop new lithographic processes and define MBOPC builds for the new lithographic process in Fab B which was transferred from a similar lithographic process in Fab A. By using PROLITHTM simulations to match OPC models for each level, minimal downtime in wafer processing was observed. Source Mask Optimization (SMO) was also used to optimize lithographic processes using novel inverse lithography techniques (ILT) to simultaneously optimize mask bias, depth of focus (DOF), exposure latitude (EL) and mask error enhancement factor (MEEF) for critical designs for each level.

Multifunctional guest-host particles engineered by reversal nanoimprint lithography

NASA Astrophysics Data System (ADS)

Ha, Uh-Myong; Kaban, Burhan; Tomita, Andreea; Krekić, Kristijan; Klintuch, Dieter; Pietschnig, Rudolf; Ehresmann, Arno; Holzinger, Dennis; Hillmer, Hartmut

2018-03-01

Particulate polymeric microfibers with incorporated europium(III)oxide (Eu2O3) nanoparticles were introduced as a magneto-photoluminescent multifunctional material fabricated via reversal nanoimprint lithography. To specifically address the volume properties of these guest-host particles, the guest, Eu2O3, was milled down to an average particle size of 350 nm in diameter and mixed with the host-polymer, AMONIL®, before in situ hardening in the imprint stamp. The variation of the fabrication process parameters, i.e. delay time, spin coating speed, as well as the concentration of Eu2O3 nanoparticles was proven to have a significant impact on both the structure quality and the stamp release of the microfibers with respect to the formation of a thinner residual layer. Structural characterization performed by SEM revealed optimum fabrication process parameters for a homogeneous spatial distribution of Eu2O3 nanoparticles within the microfibers while simultaneously avoiding the formation of undesired agglomerates. The magneto-photoluminescent properties of Eu2O3 nanoparticles, i.e. a red emission at 613 nm and a paramagnetic response, were found to be superimposed to the optic and the diamagnetic behaviors of AMONIL®. The results imply that guest-host interdependence of these properties can be excluded and that the suggested technique enables for specific tailoring of particulate multifunctional materials with focus on their volume properties.

Diffractive optical elements on non-flat substrates using electron beam lithography

NASA Technical Reports Server (NTRS)

Maker, Paul D. (Inventor); Muller, Richard E. (Inventor); Wilson, Daniel W. (Inventor)

2002-01-01

The present disclosure describes a technique for creating diffraction gratings on curved surfaces with electron beam lithography. The curved surface can act as an optical element to produce flat and aberration-free images in imaging spectrometers. In addition, the fabrication technique can modify the power structure of the grating orders so that there is more energy in the first order than for a typical grating. The inventors noticed that by using electron-beam lithography techniques, a variety of convex gratings that are well-suited to the requirements of imaging spectrometers can be manufactured.

Controlling large-scale film morphology by phase manipulation in interference lithography

NASA Astrophysics Data System (ADS)

Lu, Cheng; Hu, X. K.; Dimov, S. S.; Lipson, R. H.

2007-10-01

An experimental arrangement is described where a Babinet-Soleil compensator is inserted into the path of one of the three beams used for noncoplanar beam interference lithography. This birefringent element can change the phase of the beam so that either a positive two-dimensional pattern or an inverselike structure is generated in a photoresist without disturbing the mechanical geometry of the setup. Simulations are presented that confirm the validity of this approach. Large defect-free sample areas (>1 cm2) with submicrometer periodic patterns were obtained by expanding the laser beams used in the lithography experiment.

Polarization control in flexible interference lithography for nano-patterning of different photonic structures with optimized contrast.

PubMed

He, Jianfang; Fang, Xiaohui; Lin, Yuanhai; Zhang, Xinping

2015-05-04

Half-wave plates were introduced into an interference-lithography scheme consisting of three fibers that were arranged into a rectangular triangle. Such a flexible and compact geometry allows convenient tuning of the polarizations of both the UV laser source and each branch arm. This not only enables optimization of the contrast of the produced photonic structures with expected square lattices, but also multiplies the nano-patterning functions of a fixed design of fiber-based interference lithography. The patterns of the photonic structures can be thus tuned simply by rotating a half-wave plate.

Lithographic technologies that haven't (yet) made it: lessons learned (Plenary Paper)

NASA Astrophysics Data System (ADS)

Pease, R. Fabian

2005-05-01

Since the introduction of the integrated circuit we have been inventing ways to extend the feature resolution beyond the optical limit. Using a focused electron beam linewidths of less than 100nm were demonstrated in 1960 and a mere three years later we achieved a 10nm feature. In the 1970's and 80's several semiconductor manufacturers undertook programs to introduce electron beam lithography (EBL) and X-ray lithography (XRL) based primarily on the rationale that both had superior resolution. Those programs consumed many millions of dollars and yielded, and continue to yield, very imaginative systems but have failed to displace deep ultraviolet lithography (DUVL) despite its inferior resolution. One lesson learned is an old one: to displace an established technology the new must be 10x better than the old. Thus it is irrational that even today a form of XRL employing 13nm X-rays is still being pursued despite showing performance inferior to that of DUVL. What constitutes 'better' depends on the application and thus there are niche markets for forms of lithography other than DUVL. But for mainstream semiconductor chip manufacturing there is no prospect within the next decade of displacing optical lithography which can be stretched even to 10nm features by applying novel techniques coupled with massive computation.

Drawing lithography for microneedles: a review of fundamentals and biomedical applications.

PubMed

Lee, Kwang; Jung, Hyungil

2012-10-01

A microneedle is a three-dimensional (3D) micromechanical structure and has been in the spotlight recently as a drug delivery system (DDS). Because a microneedle delivers the target drug after penetrating the skin barrier, the therapeutic effects of microneedles proceed from its 3D structural geometry. Various types of microneedles have been fabricated using subtractive micromanufacturing methods which are based on the inherently planar two-dimensional (2D) geometries. However, traditional subtractive processes are limited for flexible structural microneedles and makes functional biomedical applications for efficient drug delivery difficult. The authors of the present study propose drawing lithography as a unique additive process for the fabrication of a microneedle directly from 2D planar substrates, thus overcoming a subtractive process shortcoming. The present article provides the first overview of the principal drawing lithography technology: fundamentals and biomedical applications. The continuous drawing technique for an ultrahigh-aspect ratio (UHAR) hollow microneedle, stepwise controlled drawing technique for a dissolving microneedle, and drawing technique with antidromic isolation for a hybrid electro-microneedle (HEM) are reviewed, and efficient biomedical applications by drawing lithography-mediated microneedles as an innovative drug and gene delivery system are described. Drawing lithography herein can provide a great breakthrough in the development of materials science and biotechnology. Copyright © 2012 Elsevier Ltd. All rights reserved.

Rapid prototyping of Fresnel zone plates via direct Ga(+) ion beam lithography for high-resolution X-ray imaging.

PubMed

Keskinbora, Kahraman; Grévent, Corinne; Eigenthaler, Ulrike; Weigand, Markus; Schütz, Gisela

2013-11-26

A significant challenge to the wide utilization of X-ray microscopy lies in the difficulty in fabricating adequate high-resolution optics. To date, electron beam lithography has been the dominant technique for the fabrication of diffractive focusing optics called Fresnel zone plates (FZP), even though this preparation method is usually very complicated and is composed of many fabrication steps. In this work, we demonstrate an alternative method that allows the direct, simple, and fast fabrication of FZPs using focused Ga(+) beam lithography practically, in a single step. This method enabled us to prepare a high-resolution FZP in less than 13 min. The performance of the FZP was evaluated in a scanning transmission soft X-ray microscope where nanostructures as small as sub-29 nm in width were clearly resolved, with an ultimate cutoff resolution of 24.25 nm, demonstrating the highest first-order resolution for any FZP fabricated by the ion beam lithography technique. This rapid and simple fabrication scheme illustrates the capabilities and the potential of direct ion beam lithography (IBL) and is expected to increase the accessibility of high-resolution optics to a wider community of researchers working on soft X-ray and extreme ultraviolet microscopy using synchrotron radiation and advanced laboratory sources.

Maskless, reticle-free, lithography

DOEpatents

Ceglio, N.M.; Markle, D.A.

1997-11-25

A lithography system in which the mask or reticle, which usually carries the pattern to be printed onto a substrate, is replaced by a programmable array of binary (i.e. on/off) light valves or switches which can be programmed to replicate a portion of the pattern each time an illuminating light source is flashed. The pattern of light produced by the programmable array is imaged onto a lithographic substrate which is mounted on a scanning stage as is common in optical lithography. The stage motion and the pattern of light displayed by the programmable array are precisely synchronized with the flashing illumination system so that each flash accurately positions the image of the pattern on the substrate. This is achieved by advancing the pattern held in the programmable array by an amount which corresponds to the travel of the substrate stage each time the light source flashes. In this manner the image is built up of multiple flashes and an isolated defect in the array will only have a small effect on the printed pattern. The method includes projection lithographies using radiation other than optical or ultraviolet light. The programmable array of binary switches would be used to control extreme ultraviolet (EUV), x-ray, or electron, illumination systems, obviating the need for stable, defect free masks for projection EUV, x-ray, or electron, lithographies. 7 figs.

Maskless, reticle-free, lithography

DOEpatents

Ceglio, Natale M.; Markle, David A.

1997-11-25

A lithography system in which the mask or reticle, which usually carries the pattern to be printed onto a substrate, is replaced by a programmable array of binary (i.e. on/off) light valves or switches which can be programmed to replicate a portion of the pattern each time an illuminating light source is flashed. The pattern of light produced by the programmable array is imaged onto a lithographic substrate which is mounted on a scanning stage as is common in optical lithography. The stage motion and the pattern of light displayed by the programmable array are precisely synchronized with the flashing illumination system so that each flash accurately positions the image of the pattern on the substrate. This is achieved by advancing the pattern held in the programmable array by an amount which corresponds to the travel of the substrate stage each time the light source flashes. In this manner the image is built up of multiple flashes and an isolated defect in the array will only have a small effect on the printed pattern. The method includes projection lithographies using radiation other than optical or ultraviolet light. The programmable array of binary switches would be used to control extreme ultraviolet (EUV), x-ray, or electron, illumination systems, obviating the need for stable, defect free masks for projection EUV, x-ray, or electron, lithographies.

SOR Lithography in West Germany

NASA Astrophysics Data System (ADS)

Heuberger, Anton

1989-08-01

The 64 Mbit DRAM will represent the first generation of integrated circuits which cannot be produced reasonably by means of optical lithography techniques. X-ray lithography using synchrotron radiation seems to be the most promising method in overcoming the problems in the sub-0.5 micron range. The first year of production of the 64 Mbit DRAM will be 1995 or 1996. This means that X-ray lithography has to show its applicability in an industrial environment by 1992 and has to prove that the specifications of a 64 Mbit DRAM technology can actually be achieved. Part of this task is a demonstration of production suitable equipment such as the X-ray stepper, including an appropriate X-ray source and measurement and inspection tools. The most important bottlenecks on the way toward reaching these goals are linked to the 1 x scale mask technology, especially the pattern definition accuracy and zero level of printing defects down to the order of magnitude of 50 nm. Specifically, fast defect detection methods on the basis of high resolution e-beam techniques and repair methods have to be developed. The other problems of X-ray lithography, such as high quality single layer X-ray resists, X-ray sources and stepper including alignment are either well on the way or are already solved.

Development and Characterization of a 3D Printed, Keratin-Based Hydrogel.

PubMed

Placone, Jesse K; Navarro, Javier; Laslo, Gregory W; Lerman, Max J; Gabard, Alexis R; Herendeen, Gregory J; Falco, Erin E; Tomblyn, Seth; Burnett, Luke; Fisher, John P

2017-01-01

Keratin, a naturally-derived polymer derived from human hair, is physiologically biodegradable, provides adequate cell support, and can self-assemble or be crosslinked to form hydrogels. Nevertheless, it has had limited use in tissue engineering and has been mainly used as casted scaffolds for drug or growth factor delivery applications. Here, we present and assess a novel method for the printed, sequential production of 3D keratin scaffolds. Using a riboflavin-SPS-hydroquinone (initiator-catalyst-inhibitor) photosensitive solution we produced 3D keratin constructs via UV crosslinking in a lithography-based 3D printer. The hydrogels obtained have adequate printing resolution and result in compressive and dynamic mechanical properties, uptake and swelling capacities, cytotoxicity, and microstructural characteristics that are comparable or superior to those of casted keratin scaffolds previously reported. The novel keratin-based printing resin and printing methodology presented have the potential to impact future research by providing an avenue to rapidly and reproducibly manufacture patient-specific hydrogels for tissue engineering and regenerative medicine applications.

Organized DFM

NASA Astrophysics Data System (ADS)

Sato, Takashi; Honma, Michio; Itoh, Hiroyuki; Iriki, Nobuyuki; Kobayashi, Sachiko; Miyazaki, Norihiko; Onodera, Toshio; Suzuki, Hiroyuki; Yoshioka, Nobuyuki; Arima, Sumika; Kadota, Kazuya

2009-04-01

The category and objective of DFM production management are shown. DFM is not limited to an activity within a particular unit process in design and process. A new framework for DFM is required. DFM should be a total solution for the common problems of all processes. Each of them must be linked to one another organically. After passing through the whole of each process on the manufacturing platform, quality of final products is guaranteed and products are shipped to the market. The information platform is layered with DFM, APC, and AEC. Advanced DFM is not DFM for partial optimization of the lithography process and the design, etc. and it should be Organized DFM. They are managed with high-level organizational IQ. The interim quality between each step of the flow should be visualized. DFM will be quality engineering if it is Organized DFM and common metrics of the quality are provided. DFM becomes quality engineering through effective implementation of common industrial metrics and standardized technology. DFM is differential technology, but can leverage standards for efficient development.

Synthetic Capillaries to Control Microscopic Blood Flow.

PubMed

Sarveswaran, K; Kurz, V; Dong, Z; Tanaka, T; Penny, S; Timp, G

2016-02-24

Capillaries pervade human physiology. The mean intercapillary distance is only about 100 μm in human tissue, which indicates the extent of nutrient diffusion. In engineered tissue the lack of capillaries, along with the associated perfusion, is problematic because it leads to hypoxic stress and necrosis. However, a capillary is not easy to engineer due to its complex cytoarchitecture. Here, it is shown that it is possible to create in vitro, in about 30 min, a tubular microenvironment with an elastic modulus and porosity consistent with human tissue that functionally mimicks a bona fide capillary using "live cell lithography"(LCL) to control the type and position of cells on a composite hydrogel scaffold. Furthermore, it is established that these constructs support the forces associated with blood flow, and produce nutrient gradients similar to those measured in vivo. With LCL, capillaries can be constructed with single cell precision-no other method for tissue engineering offers such precision. Since the time required for assembly scales with the number of cells, this method is likely to be adapted first to create minimal functional units of human tissue that constitute organs, consisting of a heterogeneous population of 100-1000 cells, organized hierarchically to express a predictable function.

Dr.LiTHO: a development and research lithography simulator

NASA Astrophysics Data System (ADS)

Fühner, Tim; Schnattinger, Thomas; Ardelean, Gheorghe; Erdmann, Andreas

2007-03-01

This paper introduces Dr.LiTHO, a research and development oriented lithography simulation environment developed at Fraunhofer IISB to flexibly integrate our simulation models into one coherent platform. We propose a light-weight approach to a lithography simulation environment: The use of a scripting (batch) language as an integration platform. Out of the great variety of different scripting languages, Python proved superior in many ways: It exhibits a good-natured learning-curve, it is efficient, available on virtually any platform, and provides sophisticated integration mechanisms for existing programs. In this paper, we will describe the steps, required to provide Python bindings for existing programs and to finally generate an integrated simulation environment. In addition, we will give a short introduction into selected software design demands associated with the development of such a framework. We will especially focus on testing and (both technical and user-oriented) documentation issues. Dr.LiTHO Python files contain not only all simulation parameter settings but also the simulation flow, providing maximum flexibility. In addition to relatively simple batch jobs, repetitive tasks can be pooled in libraries. And as Python is a full-blown programming language, users can add virtually any functionality, which is especially useful in the scope of simulation studies or optimization tasks, that often require masses of evaluations. Furthermore, we will give a short overview of the numerous existing Python packages. Several examples demonstrate the feasibility and productiveness of integrating Python packages into custom Dr.LiTHO scripts.

Miniature low voltage beam systems producable by combined lithographies

NASA Astrophysics Data System (ADS)

Koops, Hans W. P.; Munro, Eric; Rouse, John; Kretz, Johannes; Rudolph, Michael; Weber, Markus; Dahm, Gerold

The project of a miniaturized vacuum microelectronic 100 GHz switch is described. It implies the development of a field emission electron gun as well as the investigation of miniaturized lenses and deflectors. Electrostatic elements are designed and developed for this application. Connector pads and wiring pattern are created by conventional electron beam lithography and a lift-off or etching process. Wire and other 3-dimensional structures are grown using electron beam induced deposition. This additive lithography allows to form electrodes and resistors of a preset conductivity. The scanning electron microscope features positioning the structures with nm precision. An unconventional lithography system is used that is capable of controlling the pixel dwell time within a shape with different time functions. With this special function 3-dimensional structures can be generated like free standing square shaped electrodes. The switch is built by computer controlled additive lithography avoiding assembly from parts. Lenses of micrometer dimensions were investigated with numerical electron optics programs computing the 3-dimensional potential and field distribution. From the extracted axial field distribution the electron optic characteristic parameters, like focal length, chromatic and spherical aberration, were calculated for various lens excitations. The analysis reveals that miniaturized optics for low energy electrons, as low as 30 eV, are diffraction limited. For a lens with 2 μm focal length, a chromatic aberration disc of 1 nm contributes to 12 nm diffraction disc. The spherical aberration blurs the probe by 0.02 nm, assuming an aperture of 0.01 rad. Employing hydrogen ions at 100 V, a probe diameter of 0.3 nm generated by chromatic aberration is possible. Miniaturized electron optical probe forming systems and imaging systems can be constructed with those lenses. Its application as lithography systems with massive parallel beams can be forseen.

Patterning via optical saturable transitions

NASA Astrophysics Data System (ADS)

Cantu, Precious

For the past 40 years, optical lithography has been the patterning workhorse for the semiconductor industry. However, as integrated circuits have become more and more complex, and as device geometries shrink, more innovative methods are required to meet these needs. In the far-field, the smallest feature that can be generated with light is limited to approximately half the wavelength. This, so called far-field diffraction limit or the Abbe limit (after Prof. Ernst Abbe who first recognized this), effectively prevents the use of long-wavelength photons >300nm from patterning nanostructures <100nm. Even with a 193nm laser source and extremely complicated processing, patterns below ˜20nm are incredibly challenging to create. Sources with even shorter wavelengths can potentially be used. However, these tend be much more expensive and of much lower brightness, which in turn limits their patterning speed. Multi-photon reactions have been proposed to overcome the diffraction limit. However, these require very large intensities for modest gain in resolution. Moreover, the large intensities make it difficult to parallelize, thus limiting the patterning speed. In this dissertation, a novel nanopatterning technique using wavelength-selective small molecules that undergo single-photon reactions, enabling rapid top-down nanopatterning over large areas at low-light intensities, thereby allowing for the circumvention of the far-field diffraction barrier is developed and experimentally verified. This approach, which I refer to as Patterning via Optical Saturable Transitions (POST) has the potential for massive parallelism, enabling the creation of nanostructures and devices at a speed far surpassing what is currently possible with conventional optical lithographic techniques. The fundamental understanding of this technique goes beyond optical lithography in the semiconductor industry and is applicable to any area that requires the rapid patterning of large-area two or three-dimensional complex geometries. At a basic level, this research intertwines the fields of electrochemistry, material science, electrical engineering, optics, physics, and mechanical engineering with the goal of developing a novel super-resolution lithographic technique.

The range and intensity of backscattered electrons for use in the creation of high fidelity electron beam lithography patterns.

PubMed

Czaplewski, David A; Holt, Martin V; Ocola, Leonidas E

2013-08-02

We present a set of universal curves that predict the range and intensity of backscattered electrons which can be used in conjunction with electron beam lithography to create high fidelity nanoscale patterns. The experimental method combines direct write dose, backscattered dose, and a self-reinforcing pattern geometry to measure the dose provided by backscattered electrons to a nanoscale volume on the substrate surface at various distances from the electron source. Electron beam lithography is used to precisely control the number and position of incident electrons on the surface of the material. Atomic force microscopy is used to measure the height of the negative electron beam lithography resist. Our data shows that the range and the intensity of backscattered electrons can be predicted using the density and the atomic number of any solid material, respectively. The data agrees with two independent Monte Carlo simulations without any fitting parameters. These measurements are the most accurate electron range measurements to date.

ArF halftone PSM cleaning process optimization for next-generation lithography

NASA Astrophysics Data System (ADS)

Son, Yong-Seok; Jeong, Seong-Ho; Kim, Jeong-Bae; Kim, Hong-Seok

2000-07-01

ArF lithography which is expected for the next generation optical lithography is adapted for 0.13 micrometers design-rule and beyond. ArF half-tone phase shift mask (HT PSM) will be applied as 1st generation of ArF lithography. Also ArF PSM cleaning demands by means of tighter controls related to phase angle, transmittance and contamination on the masks. Phase angle on ArF HT PSM should be controlled within at least +/- 3 degree and transmittance controlled within at least +/- 3 percent after cleaning process and pelliclization. In the cleaning process of HT PSM, requires not only the remove the particle on mask, but also control to half-tone material for metamorphosis. Contamination defects on the Qz of half tone type PSM is not easy to remove on the photomask surface. New technology and methods of cleaning will be developed in near future, but we try to get out for limit contamination on the mask, without variation of phase angle and transmittance after cleaning process.

Fabrication of a Polymer Micro Needle Array by Mask-Dragging X-Ray Lithography and Alignment X-Ray Lithography

NASA Astrophysics Data System (ADS)

Li, Yi-Gui; Yang, Chun-Sheng; Liu, Jing-Quan; Sugiyama, Susumu

2011-03-01

Polymer materials such as transparent thermoplastic poly(methyl methacrylate) (PMMA) have been of great interest in the research and development of integrated circuits and micro-electromechanical systems due to their relatively low cost and easy process. We fabricated PMMA-based polymer hollow microneedle arrays by mask-dragging and aligning x-ray lithography. Techniques for 3D micromachining by direct lithography using x-rays are developed. These techniques are based on using image projection in which the x-ray is used to illuminate an appropriate gold pattern on a polyimide film mask. The mask is imaged onto the PMMA sample. A pattern with an area of up to 100 × 100mm2 can be fabricated with sub-micron resolution and a highly accurate order of a few microns by using a dragging mask. The fabrication technology has several advantages, such as forming complex 3D micro structures, high throughput and low cost.

Highly Stable Nanolattice Structures using Nonlinear Laser Lithography

NASA Astrophysics Data System (ADS)

Yavuz, Ozgun; Tokel, Onur; Ergecen, Emre; Pavlov, Ihor; Makey, Ghaith; Ilday, Fatih Omer

Periodic nanopatterning is crucial for multiple technologies, including photovoltaics and display technologies. Conventional optical lithography techniques require complex masks, while e-beam and ion-beam lithography require expensive equipment. With the Nonlinear Laser Lithography (NLL) technique, we had recently shown that various surfaces can be covered with extremely periodic nanopatterns with ultrafast lasers through a single-step, maskless and inexpensive method. Here, we expand NLL nanopatterns to flexible materials, and also present a fully predictive model for the formation of NLL nanostructures as confirmed with experiments. In NLL, a nonlocal positive feedback mechanism (dipole scattering) competes with a rate limiting negative feedback mechanism. Here, we show that judicious use of the laser polarisation can constrain the lattice symmetry, while the nonlinearities regulate periodicity. We experimentally demonstrate that in addition to one dimensional periodic stripes, two dimensional lattices can be produced on surfaces. In particular, hexagonal and square lattices were produced, which are highly desired for display technologies. Notably, with this approach, we can tile flexible substrates, which can find applications in next generation display technologies.

Suspended liquid subtractive lithography: printing three dimensional channels directly into uncured PDMS

NASA Astrophysics Data System (ADS)

Helmer, D.; Voigt, A.; Wagner, S.; Keller, N.; Sachsenheimer, K.; Kotz, F.; Nargang, T. M.; Rapp, B. E.

2018-02-01

Polydimethylsiloxane (PDMS) is one of the most widely used polymers for the generation of microfluidic chips. The standard procedures of soft lithography require the formation of a new master structure for every design which is timeconsuming and expensive. All channel generated by soft lithography need to be consecutively sealed by bonding which is a process that can proof to be hard to control. Channel cross-sections are largely restricted to squares or flat-topped designs and the generation of truly three-dimensional designs is not straightforward. Here we present Suspended Liquid Subtractive Lithography (SLSL) a method for generating microfluidic channels of nearly arbitrary three-dimensional structures in PDMS that do not require master formation or bonding and give circular channel cross sections which are especially interesting for mimicking in vivo environments. In SLSL, an immiscible liquid is introduced into the uncured PDMS by a capillary mounted on a 3D printer head. The liquid forms continuous "threads" inside the matrix thus creating void suspended channel structures.

Fabrication of cobalt magnetic nanostructures using atomic force microscope lithography.

PubMed

Chu, Haena; Yun, Seonghun; Lee, Haiwon

2013-12-01

Cobalt nanopatterns are promising assemblies for patterned magnetic storage applications. The fabrication of cobalt magnetic nanostructures on n-tridecylamine x hydrochloride (TDA x HCl) self-assembled monolayer (SAM) modified silicon surfaces using direct writing atomic force microscope (AFM) lithography for localized electrochemical reduction of cobalt ions was demonstrated. The ions were reduced to form metal nanowires along the direction of the electricfield between the AFM tip and the substrate. In this lithography process, TDA x HCI SAMs play an important role in the lithography process for improving the resolution of cobalt nanopatterns by preventing nonspecific reduction of cobalt ions on the unwritten background. Cobalt nanowires and nanodots with width of 225 +/- 26 nm and diameter of 208 +/- 28 nm were successfully fabricated. Platinium-coated polydimethylsiloxane (PDMS) stamp was used fabricating bulk cobalt structures which can be detected by energy dispersive X-ray spectroscopy for element analysis and the physical and magnetic properties of these cobalt nanopatterns were characterized using AFM and magnetic force microscope.

Compact synchrotron radiation depth lithography facility

NASA Astrophysics Data System (ADS)

Knüppel, O.; Kadereit, D.; Neff, B.; Hormes, J.

1992-01-01

X-ray depth lithography allows the fabrication of plastic microstructures with heights of up to 1 mm but with the smallest possible lateral dimensions of about 1 μm. A resist is irradiated with ``white'' synchrotron radiation through a mask that is partially covered with x-ray absorbing microstructures. The plastic microstructure is then obtained by a subsequent chemical development of the irradiated resist. In order to irradiate a reasonably large resist area, the mask and the resist have to be ``scanned'' across the vertically thin beam of the synchrotron radiation. A flexible, nonexpensive and compact scanner apparatus has been built for x-ray depth lithography at the beamline BN1 at ELSA (the 3.5 GeV Electron Stretcher and Accelerator at the Physikalisches Institut of Bonn University). Measurements with an electronic water level showed that the apparatus limits the scanner-induced structure precision to not more than 0.02 μm. The whole apparatus is installed in a vacuum chamber thus allowing lithography under different process gases and pressures.

Manipulation and simulations of thermal field profiles in laser heat-mode lithography

NASA Astrophysics Data System (ADS)

Wei, Tao; Wei, Jingsong; Wang, Yang; Zhang, Long

2017-12-01

Laser heat-mode lithography is a very useful method for high-speed fabrication of large-area micro/nanostructures. To obtain nanoscale pattern structures, one needs to manipulate the thermal diffusion channels. This work reports the manipulation of the thermal diffusion in laser heat-mode lithography and provides methods to restrain the in-plane thermal diffusion and improve the out-of-plane thermal diffusion. The thermal field profiles in heat-mode resist thin films have been given. It is found that the size of the heat-spot can be decreased by decreasing the thickness of the heat-mode resist thin films, inserting the thermal conduction layers, and shortening the laser irradiation time. The optimized laser writing strategy is also given, where the in-plane thermal diffusion is completely restrained and the out-of-plane thermal diffusion is improved. The heat-spot size is almost equal to that of the laser spot, accordingly. This work provides a very important guide to laser heat-mode lithography.

Optimal design of wide-view-angle waveplate used for polarimetric diagnosis of lithography system

NASA Astrophysics Data System (ADS)

Gu, Honggang; Jiang, Hao; Zhang, Chuanwei; Chen, Xiuguo; Liu, Shiyuan

2016-03-01

The diagnosis and control of the polarization aberrations is one of the main concerns in a hyper numerical aperture (NA) lithography system. Waveplates are basic and indispensable optical components in the polarimetric diagnosis tools for the immersion lithography system. The retardance of a birefringent waveplate is highly sensitive to the incident angle of the light, which makes the conventional waveplate not suitable to be applied in the polarimetric diagnosis for the immersion lithography system with a hyper NA. In this paper, we propose a method for the optimal design of a wideview- angle waveplate by combining two positive waveplates made from magnesium fluoride (MgF2) and two negative waveplates made from sapphire using the simulated annealing algorithm. Theoretical derivations and numerical simulations are performed and the results demonstrate that the maximum variation in the retardance of the optimally designed wide-view-angle waveplate is less than +/- 0.35° for a wide-view-angle range of +/- 20°.

Fabrication and testing of an electrochemical microcell for in situ soft X-ray microspectroscopy measurements

NASA Astrophysics Data System (ADS)

Gianoncelli, A.; Kaulich, B.; Kiskinova, M.; Mele, C.; Prasciolu, M.; Sgura, I.; Bozzini, B.

2013-03-01

In this paper we report on the fabrication and testing of a novel concept of electrochemical microcell for in-situ soft X-ray microspectroscopy in transmission. The microcell, fabricated by electron-beam lithography, implements an improved electrode design, with optimal current density distribution and minimised ohmic drop, allowing the same three-electrode electrochemical control achievable with traditional cells. Moreover standard electroanalytical measurements, such as cyclic voltammetry, can be routinely performed. As far as the electrolyte is concerned, we selected a room-temperature ionic-liquid. Some of the materials belonging to this class, in addition to a broad range of outstanding electrochemical properties, feature two highlights that are crucial for in situ, soft X-ray transmission work: spinnability, enabling accurate thickness control, and stability to UHV, allowing operation of an open cell in the analysis chamber vacuum (10-6 mbar). The cell can, of course, be used also with non-vacuum stable electrolytes in the sealed version developed in previous work in our group. In this study, the microcell designed, fabricated and tested in situ by applying an anodic polarisation to a Au electrode and following the formation of a distribution of corrosion features. This specific material combination presented in this work does not limit the cell concept, that can implement any electrodic material grown by lithography, any liquid electrolyte and any spinnable solid electrolyte.

Coaxial Lithography

NASA Astrophysics Data System (ADS)

Ozel, Tuncay

The optical and electrical properties of heterogeneous nanowires are profoundly related to their composition and nanoscale architecture. However, the intrinsic constraints of conventional synthetic and lithographic techniques have limited the types of multi-compositional nanowires that can be realized and studied in the laboratory. This thesis focuses on bridging templated electrochemical synthesis and lithography for expanding current synthetic capabilities with respect to materials generality and the ability to tailor two-dimensional growth in the formation of core-shell structures for the rational design and preparation of nanowires with very complex architectures that cannot be made by any other techniques. Chapter 1 introduces plasmonics, templated electrochemical synthesis, and on-wire lithography concepts and their significances within chemistry and materials science. Chapter 2 details a powerful technique for the deposition of metals and semiconductors with nanometer resolution in segment and gap lengths using on-wire lithography, which serves as a new platform to explore plasmon-exciton interactions in the form of long-range optical nanoscale rulers. Chapter 3 highlights an approach for the electrochemical synthesis of solution dispersible core-shell polymeric and inorganic semiconductor nanowires with metallic leads. A photodetector based on a single core-shell semiconductor nanowire is presented to demonstrate the functionality of the nanowires produced using this approach. Chapter 4 describes a new materials general technique, termed coaxial lithography (COAL), bridging templated electrochemical synthesis and lithography for generating coaxial nanowires in a parallel fashion with sub-10 nanometer resolution in both axial and radial dimensions. Combinations of coaxial nanowires composed of metals, metal oxides, metal chalcogenides, conjugated polymers, and a core/shell semiconductor nanowire with an embedded plasmonic nanoring are presented to demonstrate the possibilities afforded by COAL. Chapter 5 addresses the use of COAL for the synthesis of solution dispersible metal nanorings and nanotubes with exceptional architectural tailorability of inner diameter, outer diameter, and length leading to precise spectral control over the resulting plasmonic fields ranging from visible to the near-IR. Chapter 6 is an outlook on templated electrochemical synthesis using coaxial lithography and highlights a few promising applications from nanoparticle assembly to light-matter interactions.

EUVL masks: paving the path for commercialization

NASA Astrophysics Data System (ADS)

Mangat, Pawitter J. S.; Hector, Scott D.

2001-09-01

Optical projection lithography has been the principal vehicle of semiconductor manufacturing for more than 20 years and is marching aggressively to satisfy the needs of semiconductor manufacturers for 100nm devices. However, the complexity of optical lithography continues to increase as wavelength reduction continues to 157nm. Extreme Ultraviolet Lithography (EUVL), with wavelength from 13-14 nm, is evolving as a leading next generation lithography option for semiconductor industry to stay on the path laid by Moore's Law. Masks are a critical part of the success of any technology and are considered to be high risk both for optical lithography and NGL technologies for sub-100nm lithography. Two key areas of EUV mask fabrication are reflective multilayer deposition and absorber patterning. In the case of reflective multilayers, delivering defect free multilayers for mask blanks is the biggest challenge. Defect mitigation is being explored as a possible option to smooth the multilayer defects in addition to optimization of the deposition process to reduce defect density. The mask patterning process needs focus on the defect-free absorber stack patterning process, mask cleaning, inspection and repair. In addition, there is considerable effort to understand by simulations, the defect printability, thermal and mechanical distortions, and non-telecentric illumination, to mention a few. To protect the finished mask from defects added during use, a removable pellicle strategy combined with thermophoretic protection during exposure is being developed. Recent migration to square form factor using low thermal expansion material (LTEM) is advantageous as historical developments in optical masks can be applied to EUV mask patterning. This paper addresses recent developments in the EUV mask patterning and highlights critical manufacturing process controls needed to fabricate defect-free full field masks with CD and image placement specifications for sub-70nm node lithography. No technology can be implemented without establishing the commercial infrastructure. The rising cost seems to be a major issue affecting the technology development. With respect to mask fabrication for commercial availability, a virtual mask shop analysis is presented that indicates that the process cost for EUVL masks are comparable to the high end optical mask with a reasonable yield. However, the cost for setting up a new mask facility is considerably high.

VETA-I x ray test analysis

NASA Technical Reports Server (NTRS)

Brissenden, R. J. V.; Chartas, G.; Freeman, M. D.; Hughes, J. P.; Kellogg, E. M.; Podgorski, W. A.; Schwartz, D. A.; Zhao, P.

1992-01-01

This interim report presents some definitive results from our analysis of the VETA-I x-ray testing data. It also provides a description of the hardware and software used in the conduct of the VETA-I x-ray test program performed at the MSFC x-ray Calibration Facility (XRCF). These test results also serve to supply data and information to include in the TRW final report required by DPD 692, DR XC04. To provide an authoritative compendium of results, we have taken nine papers as published in the SPIE Symposium, 'Grazing Incidence X-ray/EUV Optics for Astronomy and Projection Lithography' and have reproduced them as the content of this report.

Enhancement of light output power of GaN-based light-emitting diodes with photonic quasi-crystal patterned on p-GaN surface and n-side sidewall roughing.

PubMed

Lai, Fang-I; Yang, Jui-Fu

2013-05-17

In this paper, GaN-based light-emitting diodes (LEDs) with photonic quasi-crystal (PQC) structure on p-GaN surface and n-side roughing by nano-imprint lithography are fabricated and investigated. At an injection current of 20 mA, the LED with PQC structure on p-GaN surface and n-side roughing increased the light output power of the InGaN/GaN multiple quantum well LEDs by a factor of 1.42, and the wall-plug efficiency is 26% higher than the conventional GaN-based LED type. After 500-h life test (55°C/50 mA), it was found that the normalized output power of GaN-based LED with PQC structure on p-GaN surface and n-side roughing only decreased by 6%. These results offer promising potential to enhance the light output powers of commercial light-emitting devices using the technique of nano-imprint lithography.

Low cost, high performance, self-aligning miniature optical systems

PubMed Central

Kester, Robert T.; Christenson, Todd; Kortum, Rebecca Richards; Tkaczyk, Tomasz S.

2009-01-01

The most expensive aspects in producing high quality miniature optical systems are the component costs and long assembly process. A new approach for fabricating these systems that reduces both aspects through the implementation of self-aligning LIGA (German acronym for lithographie, galvanoformung, abformung, or x-ray lithography, electroplating, and molding) optomechanics with high volume plastic injection molded and off-the-shelf glass optics is presented. This zero alignment strategy has been incorporated into a miniature high numerical aperture (NA = 1.0W) microscope objective for a fiber confocal reflectance microscope. Tight alignment tolerances of less than 10 μm are maintained for all components that reside inside of a small 9 gauge diameter hypodermic tubing. A prototype system has been tested using the slanted edge modulation transfer function technique and demonstrated to have a Strehl ratio of 0.71. This universal technology is now being developed for smaller, needle-sized imaging systems and other portable point-of-care diagnostic instruments. PMID:19543344

HED-TIE: A wafer-scale approach for fabricating hybrid electronic devices with trench isolated electrodes

NASA Astrophysics Data System (ADS)

Banerjee, Sreetama; Bülz, Daniel; Solonenko, Dmytro; Reuter, Danny; Deibel, Carsten; Hiller, Karla; Zahn, Dietrich R. T.; Salvan, Georgeta

2017-05-01

Organic-inorganic hybrid electronic devices (HEDs) offer opportunities for functionalities that are not easily obtainable with either organic or inorganic materials individually. In the strive for down-scaling the channel length in planar geometry HEDs, the best results were achieved with electron beam lithography or nanoimprint lithography. Their application on the wafer level is, however, cost intensive and time consuming. Here, we propose trench isolated electrode (TIE) technology as a fast, cost effective, wafer-level approach for the fabrication of planar HEDs with electrode gaps in the range of 100 nm. We demonstrate that the formation of the organic channel can be realized by deposition from solution as well as by the thermal evaporation of organic molecules. To underline one key feature of planar HED-TIEs, namely full accessibility of the active area of the devices by external stimuli such as light, 6,13-bis (triisopropylsilylethynyl) (TIPS)-pentacene/Au HED-TIEs are successfully tested for possible application as hybrid photodetectors in the visible spectral range.

Parallel compression/decompression-based datapath architecture for multibeam mask writers

NASA Astrophysics Data System (ADS)

Chaudhary, Narendra; Savari, Serap A.

2017-06-01

Multibeam electron beam systems will be used in the future for mask writing and for complimentary lithography. The major challenges of the multibeam systems are in meeting throughput requirements and in handling the large data volumes associated with writing grayscale data on the wafer. In terms of future communications and computational requirements Amdahl's Law suggests that a simple increase of computation power and parallelism may not be a sustainable solution. We propose a parallel data compression algorithm to exploit the sparsity of mask data and a grayscale video-like representation of data. To improve the communication and computational efficiency of these systems at the write time we propose an alternate datapath architecture partly motivated by multibeam direct write lithography and partly motivated by the circuit testing literature, where parallel decompression reduces clock cycles. We explain a deflection plate architecture inspired by NuFlare Technology's multibeam mask writing system and how our datapath architecture can be easily added to it to improve performance.

Parallel compression/decompression-based datapath architecture for multibeam mask writers

NASA Astrophysics Data System (ADS)

Chaudhary, Narendra; Savari, Serap A.

2017-10-01

Multibeam electron beam systems will be used in the future for mask writing and for complementary lithography. The major challenges of the multibeam systems are in meeting throughput requirements and in handling the large data volumes associated with writing grayscale data on the wafer. In terms of future communications and computational requirements, Amdahl's law suggests that a simple increase of computation power and parallelism may not be a sustainable solution. We propose a parallel data compression algorithm to exploit the sparsity of mask data and a grayscale video-like representation of data. To improve the communication and computational efficiency of these systems at the write time, we propose an alternate datapath architecture partly motivated by multibeam direct-write lithography and partly motivated by the circuit testing literature, where parallel decompression reduces clock cycles. We explain a deflection plate architecture inspired by NuFlare Technology's multibeam mask writing system and how our datapath architecture can be easily added to it to improve performance.

A 3D-printed device for polymer nanoimprint lithography

NASA Astrophysics Data System (ADS)

Caño-García, Manuel; Geday, Morten A.; Gil-Valverde, Manuel; Megías Zarco, Antonio; Otón, José M.; Quintana, Xabier

2018-02-01

Nanoimprint lithography (NIL) is an imprinting technique which has experienced an increasing popularity due to its versatility in fabrication processes. Commercial NIL machines are readily available achieving high quality results; however, these machines involve a relatively high investment. Hence, small laboratories often choose to perform NIL copies in a more rudimentary and cheaper way. A new simple system is presented in this document. It is based on two devices which can be made in-house in plastic by using a 3D printer or in aluminum. Thus, the overall manufacturing complexity is vastly reduced. The presented system includes pressure control and potentially temperature control. Replicas have been made using a sawtooth grating master with a pitch around half micrometre. High quality patterns with low density of imperfections have been achieved in 2.25 cm2 surfaces. The material chosen for the negative intermediary mould is PDMS. Tests of the imprint have been performed using the commercial hybrid polymer Ormostamp®.

Plasma Surface Interactions Common to Advanced Fusion Wall Materials and EUV Lithography - Lithium and Tin

NASA Astrophysics Data System (ADS)

Ruzic, D. N.; Alman, D. A.; Jurczyk, B. E.; Stubbers, R.; Coventry, M. D.; Neumann, M. J.; Olczak, W.; Qiu, H.

2004-09-01

Advanced plasma facing components (PFCs) are needed to protect walls in future high power fusion devices. In the semiconductor industry, extreme ultraviolet (EUV) sources are needed for next generation lithography. Lithium and tin are candidate materials in both areas, with liquid Li and Sn plasma material interactions being critical. The Plasma Material Interaction Group at the University of Illinois is leveraging liquid metal experimental and computational facilities to benefit both fields. The Ion surface InterAction eXperiment (IIAX) has measured liquid Li and Sn sputtering, showing an enhancement in erosion with temperature for light ion bombardment. Surface Cleaning of Optics by Plasma Exposure (SCOPE) measures erosion and damage of EUV mirror samples, and tests cleaning recipes with a helicon plasma. The Flowing LIquid surface Retention Experiment (FLIRE) measures the He and H retention in flowing liquid metals, with retention coefficients varying between 0.001 at 500 eV to 0.01 at 4000 eV.

Quadratic nonlinear optics to assess the morphology of riboflavin doped chitosan for eco-friendly lithography

NASA Astrophysics Data System (ADS)

Ray, Cédric; Caillau, Mathieu; Jonin, Christian; Benichou, Emmanuel; Moulin, Christophe; Salmon, Estelle; Maldonado, Melissa E.; Gomes, Anderson S. L.; Monnier, Virginie; Laurenceau, Emmanuelle; Leclercq, Jean-Louis; Chevolot, Yann; Delair, Thierry; Brevet, Pierre-François

2018-06-01

We report the use of the Second Harmonic Generation response from a riboflavin doped chitosan film as a characterization method of the film morphology. This film is of particular interest in the development of new and bio-sourced material for eco-friendly UV lithography. The method allows us to determine how riboflavin is distributed as a function of film depth in the sample. This possibility is of importance in order to have a better understanding of the riboflavin influence in chitosan films during the lithography process. On the contrary, linear optical techniques provide no information beyond the mere confirmation of the riboflavin presence.

The fabrication of nanopatterns with Au nanoparticles-embedded micelles via nanoimprint lithography.

PubMed

Lee, Jung-Pil; Kim, Eun-Uk; Koh, Haeng-Deog; Kang, Nam-Goo; Jung, Gun-Young; Lee, Jae-Suk

2009-09-09

We fabricated nanopatterns with Au nanoparticles-embedded micelles (Au-micelles) by self-assembly of block copolymers via nanoimprint lithography. The micelle structure prepared by self-assembled block copolymers was used as a template for the synthesis of Au nanoparticles (Au NPs). Au NPs were synthesized in situ inside the micelles of polystyrene-block-poly(2-vinylpyridine) (PS- b-P2VP). Au-micelles were arranged on the trenches of the polymer template, which was imprinted by nanoimprint lithography. The fabrication of line-type and dot-type nanopatterns was carried out by the combined method. In addition, multilayer nanopatterns of the Au-micelles were also proposed.

Quantum lithography beyond the diffraction limit via Rabi-oscillations

NASA Astrophysics Data System (ADS)

Liao, Zeyang; Al-Amri, Mohammad; Zubairy, M. Suhail

2011-03-01

We propose a quantum optical method to do the sub-wavelength lithography. Our method is similar to the traditional lithography but adding a critical step before dissociating the chemical bound of the photoresist. The subwavelength pattern is achieved by inducing the multi-Rabi-oscillation between the two atomic levels. The proposed method does not require multiphoton absorption and the entanglement of photons. This method is expected to be realizable using current technology. This work is supported by a grant from the Qatar National Research Fund (QNRF) under the NPRP project and a grant from the King Abdulaziz City for Science and Technology (KACST).

Inorganic resist materials based on zirconium phosphonate for atomic force microscope lithography

NASA Astrophysics Data System (ADS)

Kang, Mankyu; Kim, Seonae; Jung, JinHyuck; Kim, Heebom; Shin, Inkyun; Jeon, Chanuk; Lee, Haiwon

2014-03-01

New inorganic resist materials based on metal complexes were investigated for atomic force microscope (AFM) lithography. Phosphoric acids are good for self-assembly because of their strong binding energy. In this work, zirconium phosphonate system are newly synthesized for spin-coatable materials in aqueous solutions and leads to negative tone pattern for improving line edge roughness. Low electron exposure by AFM lithography could generate a pattern by electrochemical reaction and cross-linking of metal-oxo complexes. It has been reported that the minimum pattern results are affected by lithographic speed, and the applied voltage between a tip and a substrate.

Soft Lithography

NASA Astrophysics Data System (ADS)

Xia, Younan; Whitesides, George M.

1998-08-01

Soft lithography represents a non-photolithographic strategy based on selfassembly and replica molding for carrying out micro- and nanofabrication. It provides a convenient, effective, and low-cost method for the formation and manufacturing of micro- and nanostructures. In soft lithography, an elastomeric stamp with patterned relief structures on its surface is used to generate patterns and structures with feature sizes ranging from 30 nm to 100 mum. Five techniques have been demonstrated: microcontact printing (muCP), replica molding (REM), microtransfer molding (muTM), micromolding in capillaries (MIMIC), and solvent-assisted micromolding (SAMIM). In this chapter we discuss the procedures for these techniques and their applications in micro- and nanofabrication, surface chemistry, materials science, optics, MEMS, and microelectronics.

Fabrication of submicron structures in nanoparticle/polymer composite by holographic lithography and reactive ion etching

NASA Astrophysics Data System (ADS)

Zhang, A. Ping; He, Sailing; Kim, Kyoung Tae; Yoon, Yong-Kyu; Burzynski, Ryszard; Samoc, Marek; Prasad, Paras N.

2008-11-01

We report on the fabrication of nanoparticle/polymer submicron structures by combining holographic lithography and reactive ion etching. Silica nanoparticles are uniformly dispersed in a (SU8) polymer matrix at a high concentration, and in situ polymerization (cross-linking) is used to form a nanoparticle/polymer composite. Another photosensitive SU8 layer cast upon the nanoparticle/SU8 composite layer is structured through holographic lithography, whose pattern is finally transferred to the nanoparticle/SU8 layer by the reactive ion etching process. Honeycomb structures in a submicron scale are experimentally realized in the nanoparticle/SU8 composite.

Fabrication of 2D and 3D photonic structures using laser lithography

NASA Astrophysics Data System (ADS)

Gaso, P.; Jandura, D.; Pudis, D.

2016-12-01

In this paper we demonstrate possibilities of three-dimensional (3D) printing technology based on two photon polymerization. We used three-dimensional dip-in direct-laser-writing (DLW) optical lithography to fabricate 2D and 3D optical structures for optoelectronics and for optical sensing applications. DLW lithography allows us use a non conventional way how to couple light into the waveguide structure. We prepared ring resonator and we investigated its transmission spectral characteristic. We present 3D inverse opal structure from its design to printing and scanning electron microscope (SEM) imaging. Finally, SEM images of some prepared photonic crystal structures were performed.

Development of XUV projection lithography at 60 to 80 nm

NASA Astrophysics Data System (ADS)

Newnam, B. E.; Viswanathan, V. K.

The rationale, design, component properties, properties, and potential capabilities of extreme-ultraviolet (XUV) projection lithography systems using 60-80 nm illumination and single-surface reflectors are described. These systems are evaluated for potential application to high-volume production of future generations of gigabit chips.

Development of XUV projection lithography at 60-80 nm (Poster Paper)

NASA Astrophysics Data System (ADS)

Newnam, Brian E.; Viswanathan, Vriddhachalam K.

1992-07-01

The rationale, design, component properties, and potential capabilities of extreme-ultraviolet (XUV) projection lithography systems using 60 - 80 nm illumination and single-surface reflectors are described. These systems are evaluated for potential application to high-volume production of future generations of gigabit chips.

Graphic Arts/Offset Lithography.

ERIC Educational Resources Information Center

Hoisington, James; Metcalf, Joseph

This revised curriculum for graphic arts is designed to provide secondary and postsecondary students with entry-level skills and an understanding of current printing technology. It contains lesson plans based on entry-level competencies for offset lithography as identified by educators and industry representatives. The guide is divided into 15…

Condenser for extreme-UV lithography with discharge source

DOEpatents

Sweatt, William C.; Kubiak, Glenn D.

2001-01-01

Condenser system, for use with a ringfield camera in projection lithography, employs quasi grazing-incidence collector mirrors that are coated with a suitable reflective metal such as ruthenium to collect radiation from a discharge source to minimize the effect of contaminant accumulation on the collecting mirrors.

Sub-100-nm trackwidth development by e-beam lithography for advanced magnetic recording heads

NASA Astrophysics Data System (ADS)

Chang, Jei-Wei; Chen, Chao-Peng

2006-03-01

Although semiconductor industry ramps the products with 90 nm much quicker than anticipated [1], magnetic recording head manufacturers still have difficulties in producing sub-100 nm read/write trackwidth. Patterning for high-aspectratio writer requires much higher depth of focus (DOF) than most advanced optical lithography, including immersion technique developed recently [2]. Self-aligning reader with its stabilized bias requires a bi-layer lift-off structure where the underlayer is narrower than the top image layer. As the reader's trackwidth is below 100nm, the underlayer becomes very difficult to control. Among available approaches, e-beam lithography remains the most promising one to overcome the challenge of progressive miniaturization. In this communication, the authors discussed several approaches using ebeam lithography to achieve sub-100 nm read/write trackwidth. Our studies indicated the suspended resist bridge design can not only widen the process window for lift-off process but also makes 65 nm trackwidth feasible to manufacture. Necked dog-bone structure seems to be the best design in this application due to less proximity effects from adjacent structures and minimum blockages for ion beam etching. The trackwidth smaller than 65 nm can be fabricated via the combination of e-beam lithography with auxiliary slimming and/or trimming. However, deposit overspray through undercut becomes dominated in such a small dimension. To minimize the overspray, the effects of underlayer thickness need to be further studied.

Preparation of Octadecyltrichlorosilane Nanopatterns Using Particle Lithography: An Atomic Force Microscopy Laboratory

ERIC Educational Resources Information Center

Highland, Zachary L.; Saner, ChaMarra K.; Garno, Jayne C.

2018-01-01

Experiments are described that involve undergraduates learning concepts of nanoscience and chemistry. Students prepare nanopatterns of organosilane films using protocols of particle lithography. A few basic techniques are needed to prepare samples, such as centrifuging, mixing, heating, and drying. Students obtain hands-on skills with nanoscale…

Fabrication and Characterization of Three Dimensional Photonic Crystals Generated by Multibeam Interference Lithography

ERIC Educational Resources Information Center

Chen, Ying-Chieh

2009-01-01

Multibeam interference lithography is investigated as a manufacturing technique for three-dimensional photonic crystal templates. In this research, optimization of the optical setup and the photoresist initiation system leads to a significant improvement of the optical quality of the crystal, as characterized by normal incidence optical…

75 FR 44015 - Certain Semiconductor Products Made by Advanced Lithography Techniques and Products Containing...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-27

... INTERNATIONAL TRADE COMMISSION [Inv. No. 337-TA-729] Certain Semiconductor Products Made by... the sale within the United States after importation of certain semiconductor products made by advanced lithography techniques and products containing same by reason of infringement of certain claims of U.S. Patent...

Recent advances in particle and droplet manipulation for lab-on-a-chip devices based on surface acoustic waves.

PubMed

Wang, Zhuochen; Zhe, Jiang

2011-04-07

Manipulation of microscale particles and fluid liquid droplets is an important task for lab-on-a-chip devices for numerous biological researches and applications, such as cell detection and tissue engineering. Particle manipulation techniques based on surface acoustic waves (SAWs) appear effective for lab-on-a-chip devices because they are non-invasive, compatible with soft lithography micromachining, have high energy density, and work for nearly any type of microscale particles. Here we review the most recent research and development of the past two years in SAW based particle and liquid droplet manipulation for lab-on-a-chip devices including particle focusing and separation, particle alignment and patterning, particle directing, and liquid droplet delivery.

Tunable photonic nanojet formed by generalized Luneburg lens.

PubMed

Mao, Xiurun; Yang, Yang; Dai, Haitao; Luo, Dan; Yao, Baoli; Yan, Shaohui

2015-10-05

Nanojet has been emerging as an interesting topic in variety photonics applications. In this paper, inspired by the properties of generalized Luneburg lens (GLLs), a two-dimensional photonic nanojet system has been developed, which focal distance can be tuned by engineering the refractive index profile of GLLs. Simulation and analysis results show that the maximum light intensity, transverse and longitudinal dimensions of the photonic nanojet are dependent on the focal distance of the GLLs, thereby, by simply varying the focal distance, it is possible to obtain localized photon fluxes with different power characteristics and spatial dimensions. This can be of interest for many promising applications, such as high-resolution optical detection, optical manipulation, technology of direct-write nano-patterning and nano-lithography.

3D printed polymers toxicity profiling: a caution for biodevice applications

NASA Astrophysics Data System (ADS)

Zhu, Feng; Skommer, Joanna; Friedrich, Timo; Kaslin, Jan; Wlodkowic, Donald

2015-12-01

A recent revolution in additive manufacturing technologies and access to 3D Computer Assisted Design (CAD) software has spurred an explosive growth of new technologies in biomedical engineering. This includes biomodels for diagnosis, surgical training, hard and soft tissue replacement, biodevices and tissue engineering. Moreover, recent developments in high-definition additive manufacturing systems such as Multi-Jet Modelling (MJM) and Stereolithography (SLA), capable of reproducing feature sizes close to 100 μm, promise brand new capabilities in fabrication of optical-grade biomicrofluidic Lab-on-a-Chip and MEMS devices. Compared with other rapid prototyping technologies such as soft lithography and infrared laser micromachining in PMMA, SLA and MJM systems can enable user-friendly production of prototypes, superior feature reproduction quality and comparable levels of optical transparency. Prospectively they can revolutionize fabrication of microfluidic devices with complex geometric features and eliminate the need to use clean room environment and conventional microfabrication techniques. In this work we demonstrate preliminary data on toxicity profiling of a panel of common polymers used in 3D printing applications. The main motivation of our work was to evaluate toxicity profiles of most commonly used polymers using standardized biotests according to OECD guidelines for testing of chemic risk assessment. Our work for the first time provides a multispecies view of potential dangers and limitation for building biocompatible devices using FDM, SLA and MJM additive manufacturing systems. Our work shows that additive manufacturing holds significant promise for fabricating LOC and MEMS but requires caution when selecting systems and polymers due to toxicity exhibited by some 3D printing polymers.

Two-Photon Lithography of 3D Nanocomposite Piezoelectric Scaffolds for Cell Stimulation.

PubMed

Marino, Attilio; Barsotti, Jonathan; de Vito, Giuseppe; Filippeschi, Carlo; Mazzolai, Barbara; Piazza, Vincenzo; Labardi, Massimiliano; Mattoli, Virgilio; Ciofani, Gianni

2015-11-25

In this letter, we report on the fabrication, the characterization, and the in vitro testing of structures suitable for cell culturing, prepared through two-photon polymerization of a nanocomposite resist. More in details, commercially available Ormocomp has been doped with piezoelectric barium titanate nanoparticles, and bioinspired 3D structures resembling trabeculae of sponge bone have been fabricated. After an extensive characterization, preliminary in vitro testing demonstrated that both the topographical and the piezoelectric cues of these scaffolds are able to enhance the differentiation process of human SaOS-2 cells.

Microfabrication and Test of a Three-Dimensional Polymer Hydro-focusing Unit for Flow Cytometry Applications

NASA Technical Reports Server (NTRS)

Yang, Ren; Feeback, Daniel L.; Wang, Wan-Jun

2005-01-01

This paper details a novel three-dimensional (3D) hydro-focusing micro cell sorter for micro flow cytometry applications. The unit was microfabricated by means of SU-8 3D lithography. The 3D microstructure for coaxial sheathing was designed, microfabricated, and tested. Three-dimensional hydrofocusing capability was demonstrated with an experiment to sort labeled tanned sheep erythrocytes (red blood cells). This polymer hydro-focusing microstructure is easily microfabricated and integrated with other polymer microfluidic structures. Keywords: SU-8, three-dimensional hydro-focusing, microfluidic, microchannel, cytometer

Surface engineering approaches to micropattern surfaces for cell-based assays.

PubMed

Falconnet, Didier; Csucs, Gabor; Grandin, H Michelle; Textor, Marcus

2006-06-01

The ability to produce patterns of single or multiple cells through precise surface engineering of cell culture substrates has promoted the development of cellular bioassays that provide entirely new insights into the factors that control cell adhesion to material surfaces, cell proliferation, differentiation and molecular signaling pathways. The ability to control shape and spreading of attached cells and cell-cell contacts through the form and dimension of the cell-adhesive patches with high precision is important. Commitment of stem cells to different specific lineages depends strongly on cell shape, implying that controlled microenvironments through engineered surfaces may not only be a valuable approach towards fundamental cell-biological studies, but also of great importance for the design of cell culture substrates for tissue engineering. Furthermore, cell patterning is an important tool for organizing cells on transducers for cell-based sensing and cell-based drug discovery concepts. From a material engineering standpoint, patterning approaches have greatly profited by combining microfabrication technologies, such as photolithography, with biochemical functionalization to present to the cells biological cues in spatially controlled regions where the background is rendered non-adhesive ("non-fouling") by suitable chemical modification. The focus of this review is on the surface engineering aspects of biologically motivated micropatterning of two-dimensional (flat) surfaces with the aim to provide an introductory overview and critical assessment of the many techniques described in the literature. In particular, the importance of non-fouling surface chemistries, the combination of hard and soft lithography with molecular assembly techniques as well as a number of less well known, but useful patterning approaches, including direct cell writing, are discussed.

Capillary Force Lithography for Cardiac Tissue Engineering

PubMed Central

Macadangdang, Jesse; Lee, Hyun Jung; Carson, Daniel; Jiao, Alex; Fugate, James; Pabon, Lil; Regnier, Michael; Murry, Charles; Kim, Deok-Ho

2014-01-01

Cardiovascular disease remains the leading cause of death worldwide1. Cardiac tissue engineering holds much promise to deliver groundbreaking medical discoveries with the aims of developing functional tissues for cardiac regeneration as well as in vitro screening assays. However, the ability to create high-fidelity models of heart tissue has proven difficult. The heart’s extracellular matrix (ECM) is a complex structure consisting of both biochemical and biomechanical signals ranging from the micro- to the nanometer scale2. Local mechanical loading conditions and cell-ECM interactions have recently been recognized as vital components in cardiac tissue engineering3-5. A large portion of the cardiac ECM is composed of aligned collagen fibers with nano-scale diameters that significantly influences tissue architecture and electromechanical coupling2. Unfortunately, few methods have been able to mimic the organization of ECM fibers down to the nanometer scale. Recent advancements in nanofabrication techniques, however, have enabled the design and fabrication of scalable scaffolds that mimic the in vivo structural and substrate stiffness cues of the ECM in the heart6-9. Here we present the development of two reproducible, cost-effective, and scalable nanopatterning processes for the functional alignment of cardiac cells using the biocompatible polymer poly(lactide-co-glycolide) (PLGA)8 and a polyurethane (PU) based polymer. These anisotropically nanofabricated substrata (ANFS) mimic the underlying ECM of well-organized, aligned tissues and can be used to investigate the role of nanotopography on cell morphology and function10-14. Using a nanopatterned (NP) silicon master as a template, a polyurethane acrylate (PUA) mold is fabricated. This PUA mold is then used to pattern the PU or PLGA hydrogel via UV-assisted or solvent-mediated capillary force lithography (CFL), respectively15,16. Briefly, PU or PLGA pre-polymer is drop dispensed onto a glass coverslip and the PUA mold is placed on top. For UV-assisted CFL, the PU is then exposed to UV radiation (λ = 250-400 nm) for curing. For solvent-mediated CFL, the PLGA is embossed using heat (120 °C) and pressure (100 kPa). After curing, the PUA mold is peeled off, leaving behind an ANFS for cell culture. Primary cells, such as neonatal rat ventricular myocytes, as well as human pluripotent stem cell-derived cardiomyocytes, can be maintained on the ANFS2. PMID:24962161

Eco-friendly electron beam lithography using water-developable resist material derived from biomass

NASA Astrophysics Data System (ADS)

Takei, Satoshi; Oshima, Akihiro; Wakabayashi, Takanori; Kozawa, Takahiro; Tagawa, Seiichi

2012-07-01

We investigated the eco-friendly electron beam (EB) lithography using a high-sensitive negative type of water-developable resist material derived from biomass on hardmask layer for tri-layer processes. A water developable, non-chemically amplified, high sensitive, and negative tone resist material in EB lithography was developed for environmental affair, safety, easiness of handling, and health of the working people, instead of the common developable process of trimethylphenylammonium hydroxide. The images of 200 nm line and 800 nm space pattern with exposure dose of 7.0 μC/cm2 and CF4 etching selectivity of 2.2 with hardmask layer were provided by specific process conditions.

Light sources for high-volume manufacturing EUV lithography: technology, performance, and power scaling

NASA Astrophysics Data System (ADS)

Fomenkov, Igor; Brandt, David; Ershov, Alex; Schafgans, Alexander; Tao, Yezheng; Vaschenko, Georgiy; Rokitski, Slava; Kats, Michael; Vargas, Michael; Purvis, Michael; Rafac, Rob; La Fontaine, Bruno; De Dea, Silvia; LaForge, Andrew; Stewart, Jayson; Chang, Steven; Graham, Matthew; Riggs, Daniel; Taylor, Ted; Abraham, Mathew; Brown, Daniel

2017-06-01

Extreme ultraviolet (EUV) lithography is expected to succeed in 193-nm immersion multi-patterning technology for sub-10-nm critical layer patterning. In order to be successful, EUV lithography has to demonstrate that it can satisfy the industry requirements in the following critical areas: power, dose stability, etendue, spectral content, and lifetime. Currently, development of second-generation laser-produced plasma (LPP) light sources for the ASML's NXE:3300B EUV scanner is complete, and first units are installed and operational at chipmaker customers. We describe different aspects and performance characteristics of the sources, dose stability results, power scaling, and availability data for EUV sources and also report new development results.

Overlap junctions for high coherence superconducting qubits

NASA Astrophysics Data System (ADS)

Wu, X.; Long, J. L.; Ku, H. S.; Lake, R. E.; Bal, M.; Pappas, D. P.

2017-07-01

Fabrication of sub-micron Josephson junctions is demonstrated using standard processing techniques for high-coherence, superconducting qubits. These junctions are made in two separate lithography steps with normal-angle evaporation. Most significantly, this work demonstrates that it is possible to achieve high coherence with junctions formed on aluminum surfaces cleaned in situ by Ar plasma before junction oxidation. This method eliminates the angle-dependent shadow masks typically used for small junctions. Therefore, this is conducive to the implementation of typical methods for improving margins and yield using conventional CMOS processing. The current method uses electron-beam lithography and an additive process to define the top and bottom electrodes. Extension of this work to optical lithography and subtractive processes is discussed.

Deep X-ray lithography for the fabrication of microstructures at ELSA

NASA Astrophysics Data System (ADS)

Pantenburg, F. J.; Mohr, J.

2001-07-01

Two beamlines at the Electron Stretcher Accelerator (ELSA) of Bonn University are dedicated for the production of microstructures by deep X-ray lithography with synchrotron radiation. They are equipped with state-of-the-art X-ray scanners, maintained and used by Forschungszentrum Karlsruhe. Polymer microstructure heights between 30 and 3000 μm are manufactured regularly for research and industrial projects. This requires different characteristic energies. Therefore, ELSA operates routinely at 1.6, 2.3 and 2.7 GeV, for high-resolution X-ray mask fabrication, deep and ultra-deep X-ray lithography, respectively. The experimental setup, as well as the structure quality of deep and ultra deep X-ray lithographic microstructures are described.

Self-aligned grating couplers on template-stripped metal pyramids via nanostencil lithography

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

Klemme, Daniel J.; Johnson, Timothy W.; Mohr, Daniel A.

2016-05-23

We combine nanostencil lithography and template stripping to create self-aligned patterns about the apex of ultrasmooth metal pyramids with high throughput. Three-dimensional patterns such as spiral and asymmetric linear gratings, which can couple incident light into a hot spot at the tip, are presented as examples of this fabrication method. Computer simulations demonstrate that spiral and linear diffraction grating patterns are both effective at coupling light to the tip. The self-aligned stencil lithography technique can be useful for integrating plasmonic couplers with sharp metallic tips for applications such as near-field optical spectroscopy, tip-based optical trapping, plasmonic sensing, and heat-assisted magneticmore » recording.« less

Wafer-level micro-optics: trends in manufacturing, testing, packaging, and applications

NASA Astrophysics Data System (ADS)

Voelkel, Reinhard; Gong, Li; Rieck, Juergen; Zheng, Alan

2012-11-01

Micro-optics is an indispensable key enabling technology (KET) for many products and applications today. Probably the most prestigious examples are the diffractive light shaping elements used in high-end DUV lithography steppers. Highly efficient refractive and diffractive micro-optical elements are used for precise beam and pupil shaping. Micro-optics had a major impact on the reduction of aberrations and diffraction effects in projection lithography, allowing a resolution enhancement from 250 nm to 45 nm within the last decade. Micro-optics also plays a decisive role in medical devices (endoscopes, ophthalmology), in all laser-based devices and fiber communication networks (supercomputer, ROADM), bringing high-speed internet to our homes (FTTH). Even our modern smart phones contain a variety of micro-optical elements. For example, LED flashlight shaping elements, the secondary camera, and ambient light and proximity sensors. Wherever light is involved, micro-optics offers the chance to further miniaturize a device, to improve its performance, or to reduce manufacturing and packaging costs. Wafer-scale micro-optics fabrication is based on technology established by semiconductor industry. Thousands of components are fabricated in parallel on a wafer. We report on the state of the art in wafer-based manufacturing, testing, packaging and present examples and applications for micro-optical components and systems.

High throughput nanoimprint lithography for semiconductor memory applications

NASA Astrophysics Data System (ADS)

Ye, Zhengmao; Zhang, Wei; Khusnatdinov, Niyaz; Stachowiak, Tim; Irving, J. W.; Longsine, Whitney; Traub, Matthew; Fletcher, Brian; Liu, Weijun

2017-03-01

Imprint lithography is a promising technology for replication of nano-scale features. For semiconductor device applications, Canon deposits a low viscosity resist on a field by field basis using jetting technology. A patterned mask is lowered into the resist fluid which then quickly flows into the relief patterns in the mask by capillary action. Following this filling step, the resist is crosslinked under UV radiation, and then the mask is removed, leaving a patterned resist on the substrate. There are two critical components to meeting throughput requirements for imprint lithography. Using a similar approach to what is already done for many deposition and etch processes, imprint stations can be clustered to enhance throughput. The FPA-1200NZ2C is a four station cluster system designed for high volume manufacturing. For a single station, throughput includes overhead, resist dispense, resist fill time (or spread time), exposure and separation. Resist exposure time and mask/wafer separation are well understood processing steps with typical durations on the order of 0.10 to 0.20 seconds. To achieve a total process throughput of 17 wafers per hour (wph) for a single station, it is necessary to complete the fluid fill step in 1.2 seconds. For a throughput of 20 wph, fill time must be reduced to only one 1.1 seconds. There are several parameters that can impact resist filling. Key parameters include resist drop volume (smaller is better), system controls (which address drop spreading after jetting), Design for Imprint or DFI (to accelerate drop spreading) and material engineering (to promote wetting between the resist and underlying adhesion layer). In addition, it is mandatory to maintain fast filling, even for edge field imprinting. In this paper, we address the improvements made in all of these parameters to first enable a 1.20 second filling process for a device like pattern and have demonstrated this capability for both full fields and edge fields. Non-fill defectivity is well under 1.0 defects/cm2 for both field types. Next, by further reducing drop volume and optimizing drop patterns, a fill time of 1.1 seconds was demonstrated.

Holographically Fabricated Photonic Crystals with Large Reflectance

DTIC Science & Technology

2008-07-16

CLASSIFICATION OF: We report reflection and transmission spectra from three-dimensional polymer photonic crystals fabricated by holographic...transmission spectra from three-dimensional polymer photonic crystals fabricated by holographic lithography. The measured peak reflectance matches that... polymer photonic crystals fabricated by holographic lithography. The measured peak reflectance matches that predicted by both a finite-difference time

A fuzzy pattern matching method based on graph kernel for lithography hotspot detection

NASA Astrophysics Data System (ADS)

Nitta, Izumi; Kanazawa, Yuzi; Ishida, Tsutomu; Banno, Koji

2017-03-01

In advanced technology nodes, lithography hotspot detection has become one of the most significant issues in design for manufacturability. Recently, machine learning based lithography hotspot detection has been widely investigated, but it has trade-off between detection accuracy and false alarm. To apply machine learning based technique to the physical verification phase, designers require minimizing undetected hotspots to avoid yield degradation. They also need a ranking of similar known patterns with a detected hotspot to prioritize layout pattern to be corrected. To achieve high detection accuracy and to prioritize detected hotspots, we propose a novel lithography hotspot detection method using Delaunay triangulation and graph kernel based machine learning. Delaunay triangulation extracts features of hotspot patterns where polygons locate irregularly and closely one another, and graph kernel expresses inner structure of graphs. Additionally, our method provides similarity between two patterns and creates a list of similar training patterns with a detected hotspot. Experiments results on ICCAD 2012 benchmarks show that our method achieves high accuracy with allowable range of false alarm. We also show the ranking of the similar known patterns with a detected hotspot.

High order field-to-field corrections for imaging and overlay to achieve sub 20-nm lithography requirements

NASA Astrophysics Data System (ADS)

Mulkens, Jan; Kubis, Michael; Hinnen, Paul; de Graaf, Roelof; van der Laan, Hans; Padiy, Alexander; Menchtchikov, Boris

2013-04-01

Immersion lithography is being extended to the 20-nm and 14-nm node and the lithography performance requirements need to be tightened further to enable this shrink. In this paper we present an integral method to enable high-order fieldto- field corrections for both imaging and overlay, and we show that this method improves the performance with 20% - 50%. The lithography architecture we build for these higher order corrections connects the dynamic scanner actuators with the angle resolved scatterometer via a separate application server. Improvements of CD uniformity are based on enabling the use of freeform intra-field dose actuator and field-to-field control of focus. The feedback control loop uses CD and focus targets placed on the production mask. For the overlay metrology we use small in-die diffraction based overlay targets. Improvements of overlay are based on using the high order intra-field correction actuators on a field-tofield basis. We use this to reduce the machine matching error, extending the heating control and extending the correction capability for process induced errors.

Inverse Tomo-Lithography for Making Microscopic 3D Parts

NASA Technical Reports Server (NTRS)

White, Victor; Wiberg, Dean

2003-01-01

According to a proposal, basic x-ray lithography would be extended to incorporate a technique, called inverse tomography, that would enable the fabrication of microscopic three-dimensional (3D) objects. The proposed inverse tomo-lithographic process would make it possible to produce complex shaped, submillimeter-sized parts that would be difficult or impossible to make in any other way. Examples of such shapes or parts include tapered helices, paraboloids with axes of different lengths, and even Archimedean screws that could serve as rotors in microturbines. The proposed inverse tomo-lithographic process would be based partly on a prior microfabrication process known by the German acronym LIGA (lithographie, galvanoformung, abformung, which means lithography, electroforming, molding). In LIGA, one generates a precise, high-aspect ratio pattern by exposing a thick, x-ray-sensitive resist material to an x-ray beam through a mask that contains the pattern. One can electrodeposit metal into the developed resist pattern to form a precise metal part, then dissolve the resist to free the metal. Aspect ratios of 100:1 and patterns into resist thicknesses of several millimeters are possible.

Triple/quadruple patterning layout decomposition via linear programming and iterative rounding

NASA Astrophysics Data System (ADS)

Lin, Yibo; Xu, Xiaoqing; Yu, Bei; Baldick, Ross; Pan, David Z.

2017-04-01

As the feature size of the semiconductor technology scales down to 10 nm and beyond, multiple patterning lithography (MPL) has become one of the most practical candidates for lithography, along with other emerging technologies, such as extreme ultraviolet lithography (EUVL), e-beam lithography (EBL), and directed self-assembly. Due to the delay of EUVL and EBL, triple and even quadruple patterning is considered to be used for lower metal and contact layers with tight pitches. In the process of MPL, layout decomposition is the key design stage, where a layout is split into various parts and each part is manufactured through a separate mask. For metal layers, stitching may be allowed to resolve conflicts, whereas it is forbidden for contact and via layers. We focus on the application of layout decomposition where stitching is not allowed, such as for contact and via layers. We propose a linear programming (LP) and iterative rounding solving technique to reduce the number of nonintegers in the LP relaxation problem. Experimental results show that the proposed algorithms can provide high quality decomposition solutions efficiently while introducing as few conflicts as possible.

Photomask quality evaluation using lithography simulation and multi-detector MVM-SEM

NASA Astrophysics Data System (ADS)

Ito, Keisuke; Murakawa, Tsutomu; Fukuda, Naoki; Shida, Soichi; Iwai, Toshimichi; Matsumoto, Jun; Nakamura, Takayuki; Matsushita, Shohei; Hagiwara, Kazuyuki; Hara, Daisuke

2013-06-01

The detection and management of mask defects which are transferred onto wafer becomes more important day by day. As the photomask patterns becomes smaller and more complicated, using Inverse Lithography Technology (ILT) and Source Mask Optimization (SMO) with Optical Proximity Correction (OPC). To evaluate photomask quality, the current method uses aerial imaging by optical inspection tools. This technique at 1Xnm node has a resolution limit because small defects will be difficult to detect. We already reported the MEEF influence of high-end photomask using wide FOV SEM contour data of "E3630 MVM-SEM®" and lithography simulator "TrueMask® DS" of D2S Inc. in the prior paper [1]. In this paper we evaluate the correlation between our evaluation method and optical inspection tools as ongoing assessment. Also in order to reduce the defect classification work, we can compose the 3 Dimensional (3D) information of defects and can judge whether repairs of defects would be required. Moreover, we confirm the possibility of wafer plane CD measurement based on the combination between E3630 MVM-SEM® and 3D lithography simulation.

Fabrication of ferroelectric polymer nanostructures on flexible substrates by soft-mold reverse nanoimprint lithography

NASA Astrophysics Data System (ADS)

Song, Jingfeng; Lu, Haidong; Li, Shumin; Tan, Li; Gruverman, Alexei; Ducharme, Stephen

2016-01-01

Conventional nanoimprint lithography with expensive rigid molds is used to pattern ferroelectric polymer nanostructures on hard substrate for use in, e.g., organic electronics. The main innovation here is the use of inexpensive soft polycarbonate molds derived from recordable DVDs and reverse nanoimprint lithography at low pressure, which is compatible with flexible substrates. This approach was implemented to produce regular stripe arrays with a spacing of 700 nm from vinylidene fluoride co trifluoroethylene ferroelectric copolymer on flexible polyethylene terephthalate substrates. The nanostructures have very stable and switchable piezoelectric response and good crystallinity, and are highly promising for use in organic electronics enhanced or complemented by the unique properties of the ferroelectric polymer, such as bistable polarization, piezoelectric response, pyroelectric response, or electrocaloric function. The soft-mold reverse nanoimprint lithography also leaves little or no residual layer, affording good isolation of the nanostructures. This approach reduces the cost and facilitates large-area, high-throughput production of isolated functional polymer nanostructures on flexible substrates for the increasing application of ferroelectric polymers in flexible electronics.

3D Microfabrication Using Emulsion Mask Grayscale Photolithography Technique

NASA Astrophysics Data System (ADS)

Lee, Tze Pin; Mohamed, Khairudin

2016-02-01

Recently, the rapid development of technology such as biochips, microfluidic, micro-optical devices and micro-electromechanical-systems (MEMS) demands the capability to create complex design of three-dimensional (3D) microstructures. In order to create 3D microstructures, the traditional photolithography process often requires multiple photomasks to form 3D pattern from several stacked photoresist layers. This fabrication method is extremely time consuming, low throughput, costly and complicated to conduct for high volume manufacturing scale. On the other hand, next generation lithography such as electron beam lithography (EBL), focused ion beam lithography (FIB) and extreme ultraviolet lithography (EUV) are however too costly and the machines require expertise to setup. Therefore, the purpose of this study is to develop a simplified method in producing 3D microstructures using single grayscale emulsion mask technique. By using this grayscale fabrication method, microstructures of thickness as high as 500μm and as low as 20μm are obtained in a single photolithography exposure. Finally, the fabrication of 3D microfluidic channel has been demonstrated by using this grayscale photolithographic technique.

Fabrication of ferroelectric polymer nanostructures on flexible substrates by soft-mold reverse nanoimprint lithography.

PubMed

Song, Jingfeng; Lu, Haidong; Li, Shumin; Tan, Li; Gruverman, Alexei; Ducharme, Stephen

2016-01-08

Conventional nanoimprint lithography with expensive rigid molds is used to pattern ferroelectric polymer nanostructures on hard substrate for use in, e.g., organic electronics. The main innovation here is the use of inexpensive soft polycarbonate molds derived from recordable DVDs and reverse nanoimprint lithography at low pressure, which is compatible with flexible substrates. This approach was implemented to produce regular stripe arrays with a spacing of 700 nm from vinylidene fluoride co trifluoroethylene ferroelectric copolymer on flexible polyethylene terephthalate substrates. The nanostructures have very stable and switchable piezoelectric response and good crystallinity, and are highly promising for use in organic electronics enhanced or complemented by the unique properties of the ferroelectric polymer, such as bistable polarization, piezoelectric response, pyroelectric response, or electrocaloric function. The soft-mold reverse nanoimprint lithography also leaves little or no residual layer, affording good isolation of the nanostructures. This approach reduces the cost and facilitates large-area, high-throughput production of isolated functional polymer nanostructures on flexible substrates for the increasing application of ferroelectric polymers in flexible electronics.

ESH assessment of advanced lithography materials and processes

NASA Astrophysics Data System (ADS)

Worth, Walter F.; Mallela, Ram

2004-05-01

The ESH Technology group at International SEMATECH is conducting environment, safety, and health (ESH) assessments in collaboration with the lithography technologists evaluating the performance of an increasing number of new materials and technologies being considered for advanced lithography such as 157nm photresist and extreme ultraviolet (EUV). By performing data searches for 75 critical data types, emissions characterizations, and industrial hygiene (IH) monitoring during the use of the resist candidates, it has been shown that the best performing resist formulations, so far, appear to be free of potential ESH concerns. The ESH assessment of the EUV lithography tool that is being developed for SEMATECH has identified several features of the tool that are of ESH concern: high energy consumption, poor energy conversion efficiency, tool complexity, potential ergonomic and safety interlock issues, use of high powered laser(s), generation of ionizing radiation (soft X-rays), need for adequate shielding, and characterization of the debris formed by the extreme temperature of the plasma. By bringing these ESH challenges to the attention of the technologists and tool designers, it is hoped that the processes and tools can be made more ESH friendly.

Nearly amorphous Mo-N gratings for ultimate resolution in extreme ultraviolet interference lithography

NASA Astrophysics Data System (ADS)

Wang, L.; Kirk, E.; Wäckerlin, C.; Schneider, C. W.; Hojeij, M.; Gobrecht, J.; Ekinci, Y.

2014-06-01

We present fabrication and characterization of high-resolution and nearly amorphous Mo1 - xNx transmission gratings and their use as masks for extreme ultraviolet (EUV) interference lithography. During sputter deposition of Mo, nitrogen is incorporated into the film by addition of N2 to the Ar sputter gas, leading to suppression of Mo grain growth and resulting in smooth and homogeneous thin films with a negligible grain size. The obtained Mo0.8N0.2 thin films, as determined by x-ray photoelectron spectroscopy, are characterized to be nearly amorphous using x-ray diffraction. We demonstrate a greatly reduced Mo0.8N0.2 grating line edge roughness compared with pure Mo grating structures after e-beam lithography and plasma dry etching. The amorphous Mo0.8N0.2 thin films retain, to a large extent, the benefits of Mo as a phase grating material for EUV wavelengths, providing great advantages for fabrication of highly efficient diffraction gratings with extremely low roughness. Using these grating masks, well-resolved dense lines down to 8 nm half-pitch are fabricated with EUV interference lithography.

Fabrication of hierarchical micro-nanotopographies for cell attachment studies.

PubMed

López-Bosque, M J; Tejeda-Montes, E; Cazorla, M; Linacero, J; Atienza, Y; Smith, K H; Lladó, A; Colombelli, J; Engel, E; Mata, A

2013-06-28

We report on the development of micro/nanofabrication processes to create hierarchical surface topographies that expand from 50 nm to microns in size on different materials. Three different approaches (named FIB1, FIB2, and EBL) that combine a variety of techniques such as photolithography, reactive ion etching, focused ion beam lithography, electron beam lithography, and soft lithography were developed, each one providing different advantages and disadvantages. The EBL approach was employed to fabricate substrates comprising channels with features between 200 nm and 10 μm in size on polymethylmethacrylate (PMMA), which were then used to investigate the independent or competitive effects of micro- and nanotopographies on cell adhesion and morphology. Rat mesenchymal stem cells (rMSCs) were cultured on four different substrates including 10 μm wide and 500 nm deep channels separated by 10 μm distances (MICRO), 200 nm wide and 100 nm deep nanochannels separated by 200 nm distances (NANO), their combination in parallel (PARAL), and in a perpendicular direction (PERP). Rat MSCs behaved differently on all tested substrates with a high degree of alignment (as measured by both number of aligned cells and average angle) on both NANO and MICRO. Furthermore, cells exhibited the highest level of alignment on PARAL, suggesting a synergetic effect of the two scales of topographies. On the other hand, cells on PERP exhibited the lowest alignment and a consistent change in morphology over time that seemed to be the result of interactions with both micro- and nanochannels positioned in the perpendicular direction, also suggesting a competitive effect of the topographies.

Report on the fifth workshop on synchrotron x ray lithography

NASA Astrophysics Data System (ADS)

Williams, G. P.; Godel, J. B.; Brown, G. S.; Liebmann, W.

Semiconductors comprise a greater part of the United States economy than the aircraft, steel, and automobile industries combined. In future the semiconductor manufacturing industry will be forced to switch away from present optical manufacturing methods in the early to mid 1990s. X ray lithography has emerged as the leading contender for continuing production below the 0.4 micron level. Brookhaven National Laboratory began a series of workshops on x ray lithography in 1986 to examine key issues and in particular to enable United States industry to take advantage of the technical base established in this field. Since accelerators provide the brightest sources for x ray lithography, most of the research and development to date has taken place at large accelerator-based research centers such as Brookhaven, the University of Wisconsin, and Stanford. The goals of this Fifth Brookhaven Workshop were to review progress and goals since the last workshop and to establish a blueprint for the future. The meeting focused on the exposure tool, that is, a term defined as the source plus beamline and stepper. In order to assess the appropriateness of schedules for the development of this tool, other aspects of the required technology such as masks, resists and inspection and repair were also reviewed. To accomplish this, two working groups were set up, one to review the overall aspects of x ray lithography and set a time frame, the other to focus on sources.

Nanosphere lithography applied to magnetic thin films

NASA Astrophysics Data System (ADS)

Gleason, Russell

Magnetic nanostructures have widespread applications in many areas of physics and engineering, and nanosphere lithography has recently emerged as promising tool for the fabrication of such nanostructures. The goal of this research is to explore the magnetic properties of a thin film of ferromagnetic material deposited onto a hexagonally close-packed monolayer array of polystyrene nanospheres, and how they differ from the magnetic properties of a typical flat thin film. The first portion of this research focuses on determining the optimum conditions for depositing a monolayer of nanospheres onto chemically pretreated silicon substrates (via drop-coating) and the subsequent characterization of the deposited nanosphere layer with scanning electron microscopy. Single layers of permalloy (Ni80Fe20) are then deposited on top of the nanosphere array via DC magnetron sputtering, resulting in a thin film array of magnetic nanocaps. The coercivities of the thin films are measured using a home-built magneto-optical Kerr effect (MOKE) system in longitudinal arrangement. MOKE measurements show that for a single layer of permalloy (Py), the coercivity of a thin film deposited onto an array of nanospheres increases compared to that of a flat thin film. In addition, the coercivity increases as the nanosphere size decreases for the same deposited layer. It is postulated that magnetic exchange decoupling between neighboring nanocaps suppresses the propagation of magnetic domain walls, and this pinning of the domain walls is thought to be the primary source of the increase in coercivity.

Meeting critical gate linewidth control needs at the 65 nm node

NASA Astrophysics Data System (ADS)

Mahorowala, Arpan; Halle, Scott; Gabor, Allen; Chu, William; Barberet, Alexandra; Samuels, Donald; Abdo, Amr; Tsou, Len; Yan, Wendy; Iseda, Seiji; Patel, Kaushal; Dirahoui, Bachir; Nomura, Asuka; Ahsan, Ishtiaq; Azam, Faisal; Berg, Gary; Brendler, Andrew; Zimmerman, Jeffrey; Faure, Tom

2006-03-01

With the nominal gate length at the 65 nm node being only 35 nm, controlling the critical dimension (CD) in polysilicon to within a few nanometers is essential to achieve a competitive power-to-performance ratio. Gate linewidths must be controlled, not only at the chip level so that the chip performs as the circuit designers and device engineers had intended, but also at the wafer level so that more chips with the optimum power-to-performance ratio are manufactured. Achieving tight across-chip linewidth variation (ACLV) and chip mean variation (CMV) is possible only if the mask-making, lithography, and etching processes are all controlled to very tight specifications. This paper identifies the various ACLV and CMV components, describes their root causes, and discusses a methodology to quantify them. For example, the site-to-site ACLV component is divided into systematic and random sub-components. The systematic component of the variation is attributed in part to pattern density variation across the field, and variation in exposure dose across the slit. The paper demonstrates our team's success in achieving the tight gate CD tolerances required for 65 nm technology. Certain key challenges faced, and methods employed to overcome them are described. For instance, the use of dose-compensation strategies to correct the small but systematic CD variations measured across the wafer, is described. Finally, the impact of immersion lithography on both ACLV and CMV is briefly discussed.

Exploring EUV and SAQP pattering schemes at 5nm technology node

NASA Astrophysics Data System (ADS)

Hamed Fatehy, Ahmed; Kotb, Rehab; Lafferty, Neal; Jiang, Fan; Word, James

2018-03-01

For years, Moore's law keeps driving the semiconductors industry towards smaller dimensions and higher density chips with more devices. Earlier, the correlation between exposure source's wave length and the smallest resolvable dimension, mandated the usage of Deep Ultra-Violent (DUV) optical lithography system which has been used for decades to sustain Moore's law, especially when immersion lithography was introduced with 193nm ArF laser sources. As dimensions of devices get smaller beyond Deep Ultra-Violent (DUV) optical resolution limits, the need for Extremely Ultra-Violent (EUV) optical lithography systems was a must. However, EUV systems were still under development at that time for the mass-production in semiconductors industry. Theretofore, Multi-Patterning (MP) technologies was introduced to swirl about DUV optical lithography limitations in advanced nodes beyond minimum dimension (CD) of 20nm. MP can be classified into two main categories; the first one is to split the target itself across multiple masks that give the original target patterns when they are printed. This category includes Double, Triple and Quadruple patterning (DP, TP, and QP). The second category is the Self-Aligned Patterning (SAP) where the target is divided into Mandrel patterns and non-Mandrel patterns. The Mandrel patterns get printed first, then a self-aligned sidewalls are grown around these printed patterns drawing the other non-Mandrel targets, afterword, a cut mask(s) is used to define target's line-ends. This approach contains Self-Aligned-Double Pattering (SADP) and Self-Aligned- Quadruple-Pattering (SAQP). DUV and MP along together paved the way for the industry down to 7nm. However, with the start of development at the 5nm node and the readiness of EUV, the differentiation question is aroused again, which pattering approach should be selected, direct printing using EUV or DUV with MP, or a hybrid flow that contains both DUV-MP and EUV. In this work we are comparing two potential pattering techniques for Back End Of Line (BEOL) metal layers in the 5nm technology node, the first technique is Single Exposure EUV (SE-EUV) with a Direct Patterning EUV lithography process, and the second one is Self-Aligned Quadruple Patterning (SAQP) with a hybrid lithography processes, where the drawn metal target layer is decomposed into a Mandrel mask and Blocks/Cut mask, Mandrel mask is printed using DUV 193i lithography process, while Block/Cut Mask is printed using SE-EUV lithography process. The pros and cons of each technique are quantified based on Edge-Placement-Error (EPE) and Process Variation Band (PVBand) measured at 1D and 2D edges. The layout used in this comparison is a candidate layout for Foundries 5nm process node.

Resolution Improvement and Pattern Generator Development for theMaskless Micro-Ion-Beam Reduction Lithography System

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

Jiang, Ximan

The shrinking of IC devices has followed the Moore's Law for over three decades, which states that the density of transistors on integrated circuits will double about every two years. This great achievement is obtained via continuous advance in lithography technology. With the adoption of complicated resolution enhancement technologies, such as the phase shifting mask (PSM), the optical proximity correction (OPC), optical lithography with wavelength of 193 nm has enabled 45 nm printing by immersion method. However, this achievement comes together with the skyrocketing cost of masks, which makes the production of low volume application-specific IC (ASIC) impractical. In ordermore » to provide an economical lithography approach for low to medium volume advanced IC fabrication, a maskless ion beam lithography method, called Maskless Micro-ion-beam Reduction Lithography (MMRL), has been developed in the Lawrence Berkeley National Laboratory. The development of the prototype MMRL system has been described by Dr. Vinh Van Ngo in his Ph.D. thesis. But the resolution realized on the prototype MMRL system was far from the design expectation. In order to improve the resolution of the MMRL system, the ion optical system has been investigated. By integrating a field-free limiting aperture into the optical column, reducing the electromagnetic interference and cleaning the RF plasma, the resolution has been improved to around 50 nm. Computational analysis indicates that the MMRL system can be operated with an exposure field size of 0.25 mm and a beam half angle of 1.0 mrad on the wafer plane. Ion-ion interactions have been studied with a two-particle physics model. The results are in excellent agreement with those published by the other research groups. The charge-interaction analysis of MMRL shows that the ion-ion interactions must be reduced in order to obtain a throughput higher than 10 wafers per hour on 300-mm wafers. In addition, two different maskless lithography strategies have been studied. The dependence of the throughput with the exposure field size and the speed of the mechanical stage has been investigated. In order to perform maskless lithography, different micro-fabricated pattern generators have been developed for the MMRL system. Ion beamlet switching has been successfully demonstrated on the MMRL system. A positive bias voltage around 10 volts is sufficient to switch off the ion current on the micro-fabricated pattern generators. Some unexpected problems, such as the high-energy secondary electron radiations, have been discovered during the experimental investigation. Thermal and structural analysis indicates that the aperture displacement error induced by thermal expansion can satisfy the 3δ CD requirement for lithography nodes down to 25 nm. The cross-talking effect near the surface and inside the apertures of the pattern generator has been simulated in a 3-D ray-tracing code. New pattern generator design has been proposed to reduce the cross-talking effect. In order to eliminate the surface charging effect caused by the secondary electrons, a new beam-switching scheme in which the switching electrodes are immersed in the plasma has been demonstrated on a mechanically fabricated pattern generator.« less

A Low-Cost Hands-On Laboratory to Introduce Lithography Concepts

ERIC Educational Resources Information Center

Jalali, M.; Marti, J. J.; Kirchhoff, A. L.; Lawrenz, F.; Campbell, S. A.

2012-01-01

A lithography lab course has been developed that is applicable to students from the middle-school level up to college students. It can also be inserted into electronics technology or similar courses in two- and four-year colleges, or used to demonstrate applications of polymers in chemistry classes. Some of these techniques would enable research…

Selective Etching via Soft Lithography of Conductive Multilayered Gold Films with Analysis of Electrolyte Solutions

ERIC Educational Resources Information Center

Gerber, Ralph W.; Oliver-Hoyo, Maria T.

2008-01-01

This experiment is designed to expose undergraduate students to the process of selective etching by using soft lithography and the resulting electrical properties of multilayered films fabricated via self-assembly of gold nanoparticles. Students fabricate a conductive film of gold on glass, apply a patterned resist using a polydimethylsiloxane…

A Computer-Based, Interactive Videodisc Job Aid and Expert System for Electron Beam Lithography Integration and Diagnostic Procedures.

ERIC Educational Resources Information Center

Stevenson, Kimberly

This master's thesis describes the development of an expert system and interactive videodisc computer-based instructional job aid used for assisting in the integration of electron beam lithography devices. Comparable to all comprehensive training, expert system and job aid development require a criterion-referenced systems approach treatment to…

Scalable fabrication of nanostructured devices on flexible substrates using additive driven self-assembly and nanoimprint lithography

NASA Astrophysics Data System (ADS)

Watkins, James

2013-03-01

Roll-to-roll (R2R) technologies provide routes for continuous production of flexible, nanostructured materials and devices with high throughput and low cost. We employ additive-driven self-assembly to produce well-ordered polymer/nanoparticle hybrid materials that can serve as active device layers, we use highly filled nanoparticle/polymer hybrids for applications that require tailored dielectric constant or refractive index, and we employ R2R nanoimprint lithography for device scale patterning. Specific examples include the fabrication of flexible floating gate memory and large area films for optical/EM management. Our newly constructed R2R processing facility includes a custom designed, precision R2R UV-assisted nanoimprint lithography (NIL) system and hybrid nanostructured materials coaters.

Plastic masters-rigid templates for soft lithography.

PubMed

Desai, Salil P; Freeman, Dennis M; Voldman, Joel

2009-06-07

We demonstrate a simple process for the fabrication of rigid plastic master molds for soft lithography directly from (poly)dimethysiloxane devices. Plastics masters (PMs) provide a cost-effective alternative to silicon-based masters and can be easily replicated without the need for cleanroom facilities. We have successfully demonstrated the use of plastics micromolding to generate both single and dual-layer plastic structures, and have characterized the fidelity of the molding process. Using the PM fabrication technique, world-to-chip connections can be integrated directly into the master enabling devices with robust, well-aligned fluidic ports directly after molding. PMs provide an easy technique for the fabrication of microfluidic devices and a simple route for the scaling-up of fabrication of robust masters for soft lithography.

Monolayer graphene-insulator-semiconductor emitter for large-area electron lithography

NASA Astrophysics Data System (ADS)

Kirley, Matthew P.; Aloui, Tanouir; Glass, Jeffrey T.

2017-06-01

The rapid adoption of nanotechnology in fields as varied as semiconductors, energy, and medicine requires the continual improvement of nanopatterning tools. Lithography is central to this evolving nanotechnology landscape, but current production systems are subject to high costs, low throughput, or low resolution. Herein, we present a solution to these problems with the use of monolayer graphene in a graphene-insulator-semiconductor (GIS) electron emitter device for large-area electron lithography. Our GIS device displayed high emission efficiency (up to 13%) and transferred large patterns (500 × 500 μm) with high fidelity (<50% spread). The performance of our device demonstrates a feasible path to dramatic improvements in lithographic patterning systems, enabling continued progress in existing industries and opening opportunities in nanomanufacturing.

Phase-conjugate holographic lithography based on micromirror array recording.

PubMed

Lim, Yongjun; Hahn, Joonku; Lee, Byoungho

2011-12-01

We present phase-conjugate holographic lithography with a hologram recorded by a digital micromirror device (DMD) and a telecentric lens. In our lithography system, a phase-conjugate hologram is applied instead of conventional masks or reticles to form patterns. This method has the advantage of increasing focus range, and it is applicable to the formation of patterns on fairly uneven surfaces. The hologram pattern is dynamically generated by the DMD, and its resolution is mainly determined by the demagnification of the telecentric lens. We experimentally demonstrate that our holographic lithographic system has a large focus range, and it is feasible to make a large-area hologram by stitching each pattern generated by the DMD without a falling off in resolution. © 2011 Optical Society of America

In-Process Atomic-Force Microscopy (AFM) Based Inspection

PubMed Central

Mekid, Samir

2017-01-01

A new in-process atomic-force microscopy (AFM) based inspection is presented for nanolithography to compensate for any deviation such as instantaneous degradation of the lithography probe tip. Traditional method used the AFM probes for lithography work and retract to inspect the obtained feature but this practice degrades the probe tip shape and hence, affects the measurement quality. This paper suggests a second dedicated lithography probe that is positioned back-to-back to the AFM probe under two synchronized controllers to correct any deviation in the process compared to specifications. This method shows that the quality improvement of the nanomachining, in progress probe tip wear, and better understanding of nanomachining. The system is hosted in a recently developed nanomanipulator for educational and research purposes. PMID:28561747

Nanofabrication on unconventional substrates using transferred hard masks

DOE PAGES

Li, Luozhou; Bayn, Igal; Lu, Ming; ...

2015-01-15

Here, a major challenge in nanofabrication is to pattern unconventional substrates that cannot be processed for a variety of reasons, such as incompatibility with spin coating, electron beam lithography, optical lithography, or wet chemical steps. Here, we present a versatile nanofabrication method based on re-usable silicon membrane hard masks, patterned using standard lithography and mature silicon processing technology. These masks, transferred precisely onto targeted regions, can be in the millimetre scale. They allow for fabrication on a wide range of substrates, including rough, soft, and non-conductive materials, enabling feature linewidths down to 10 nm. Plasma etching, lift-off, and ion implantationmore » are realized without the need for scanning electron/ion beam processing, UV exposure, or wet etching on target substrates.« less

Fabrication of Nonperiodic Metasurfaces by Microlens Projection Lithography.

PubMed

Gonidec, Mathieu; Hamedi, Mahiar M; Nemiroski, Alex; Rubio, Luis M; Torres, Cesar; Whitesides, George M

2016-07-13

This paper describes a strategy that uses template-directed self-assembly of micrometer-scale microspheres to fabricate arrays of microlenses for projection photolithography of periodic, quasiperiodic, and aperiodic infrared metasurfaces. This method of "template-encoded microlens projection lithography" (TEMPL) enables rapid prototyping of planar, multiscale patterns of similarly shaped structures with critical dimensions down to ∼400 nm. Each of these structures is defined by local projection lithography with a single microsphere acting as a lens. This paper explores the use of TEMPL for the fabrication of a broad range of two-dimensional lattices with varying types of nonperiodic spatial distribution. The matching optical spectra of the fabricated and simulated metasurfaces confirm that TEMPL can produce structures that conform to expected optical behavior.

X-ray lithography source

DOEpatents

Piestrup, Melvin A.; Boyers, David G.; Pincus, Cary

1991-01-01

A high-intensity, inexpensive X-ray source for X-ray lithography for the production of integrated circuits. Foil stacks are bombarded with a high-energy electron beam of 25 to 250 MeV to produce a flux of soft X-rays of 500 eV to 3 keV. Methods of increasing the total X-ray power and making the cross section of the X-ray beam uniform are described. Methods of obtaining the desired X-ray-beam field size, optimum frequency spectrum and elminating the neutron flux are all described. A method of obtaining a plurality of station operation is also described which makes the process more efficient and economical. The satisfying of these issues makes transition radiation an exellent moderate-priced X-ray source for lithography.

Mask-induced aberration in EUV lithography

NASA Astrophysics Data System (ADS)

Nakajima, Yumi; Sato, Takashi; Inanami, Ryoichi; Nakasugi, Tetsuro; Higashiki, Tatsuhiko

2009-04-01

We estimated aberrations using Zernike sensitivity analysis. We found the difference of the tolerated aberration with line direction for illumination. The tolerated aberration of perpendicular line for illumination is much smaller than that of parallel line. We consider this difference to be attributable to the mask 3D effect. We call it mask-induced aberration. In the case of the perpendicular line for illumination, there was a difference in CD between right line and left line without aberration. In this report, we discuss the possibility of pattern formation in NA 0.25 generation EUV lithography tool. In perpendicular pattern for EUV light, the dominant part of aberration is mask-induced aberration. In EUV lithography, pattern correction based on the mask topography effect will be more important.

Active Surfaces and Interfaces of Soft Materials

NASA Astrophysics Data System (ADS)

Wang, Qiming

A variety of intriguing surface patterns have been observed on developing natural systems, ranging from corrugated surface of white blood cells at nanometer scales to wrinkled dog skins at millimeter scales. To mimetically harness functionalities of natural morphologies, artificial transformative skin systems by using soft active materials have been rationally designed to generate versatile patterns for a variety of engineering applications. The study of the mechanics and design of these dynamic surface patterns on soft active materials are both physically interesting and technologically important. This dissertation starts with studying abundant surface patterns in Nature by constructing a unified phase diagram of surface instabilities on soft materials with minimum numbers of physical parameters. Guided by this integrated phase diagram, an electroactive system is designed to investigate a variety of electrically-induced surface instabilities of elastomers, including electro-creasing, electro-cratering, electro-wrinkling and electro-cavitation. Combing experimental, theoretical and computational methods, the initiation, evolution and transition of these instabilities are analyzed. To apply these dynamic surface instabilities to serving engineering and biology, new techniques of Dynamic Electrostatic Lithography and electroactive anti-biofouling are demonstrated.

High throughput, high resolution enzymatic lithography process: effect of crystallite size, moisture, and enzyme concentration.

PubMed

Mao, Zhantong; Ganesh, Manoj; Bucaro, Michael; Smolianski, Igor; Gross, Richard A; Lyons, Alan M

2014-12-08

By bringing enzymes into contact with predefined regions of a surface, a polymer film can be selectively degraded to form desired patterns that find a variety of applications in biotechnology and electronics. This so-called "enzymatic lithography" is an environmentally friendly process as it does not require actinic radiation or synthetic chemicals to develop the patterns. A significant challenge to using enzymatic lithography has been the need to restrict the mobility of the enzyme in order to maintain control of feature sizes. Previous approaches have resulted in low throughput and were limited to polymer films only a few nanometers thick. In this paper, we demonstrate an enzymatic lithography system based on Candida antartica lipase B (CALB) and poly(ε-caprolactone) (PCL) that can resolve fine-scale features, (<1 μm across) in thick (0.1-2.0 μm) polymer films. A Polymer Pen Lithography (PPL) tool was developed to deposit an aqueous solution of CALB onto a spin-cast PCL film. Immobilization of the enzyme on the polymer surface was monitored using fluorescence microscopy by labeling CALB with FITC. The crystallite size in the PCL films was systematically varied; small crystallites resulted in significantly faster etch rates (20 nm/min) and the ability to resolve smaller features (as fine as 1 μm). The effect of printing conditions and relative humidity during incubation is also presented. Patterns formed in the PCL film were transferred to an underlying copper foil demonstrating a "Green" approach to the fabrication of printed circuit boards.

Finding the right way: DFM versus area efficiency for 65 nm gate layer lithography

NASA Astrophysics Data System (ADS)

Sarma, Chandra S.; Scheer, Steven; Herold, Klaus; Fonseca, Carlos; Thomas, Alan; Schroeder, Uwe P.

2006-03-01

DFM (Design for Manufacturing) has become a buzzword for lithography since the 90nm node. Implementing DFM intelligently can boost yield rates and reliability in semiconductor manufacturing significantly. However, any restriction on the design space will always result in an area loss, thus diminishing the effective shrink factor for a given technology. For a lithographer, the key task is to develop a manufacturable process, while not sacrificing too much area. We have developed a high performing lithography process for attenuated gate level lithography that is based on aggressive illumination and a newly optimized SRAF placement schemes. In this paper we present our methodology and results for this optimization, using an anchored simulation model. The wafer results largely confirm the predictions of the simulations. The use of aggressive SRAF (Sub Resolution Assist Features) strategy leads to reduction of forbidden pitch regions without any SRAF printing. The data show that our OPC is capable of correcting the PC tip to tip distance without bridging between the tips in dense SRAM cells. SRAF strategy for various 2D cases has also been verified on wafer. We have shown that aggressive illumination schemes yielding a high performing lithography process can be employed without sacrificing area. By carefully choosing processing conditions, we were able develop a process that has very little restrictions for design. In our approach, the remaining issues can be addressed by DFM, partly in data prep procedures, which are largely area neutral and transparent to the designers. Hence, we have shown successfully, that DFM and effective technology shrinks are not mutually exclusive.

Innovative method to suppress local geometry distortions for fabrication of interdigitated electrode arrays with nano gaps

NASA Astrophysics Data System (ADS)

Partel, S.; Urban, G.

2016-03-01

In this paper we present a method to optimize the lithography process for the fabrication of interdigitated electrode arrays (IDA) for a lift-off free electrochemical biosensor. The biosensor is based on amperometric method to allow a signal amplification by redox cycling. We already demonstrated a method to fabricate IDAs with nano gaps with conventional mask aligner lithography and two subsequent deposition processes. By decreasing the distance down to the nanometer range the linewidth variation is becoming the most critical factor and can result in a short circuit of the electrodes. Therefore, the light propagation and the resist pattern of the mask aligner lithography process are simulated to optimize the lithography process. To optimize the outer finger structure assistant features (AsFe) were introduced. The AsFe allow an optimization of the intensity distribution at the electrode fingers. Hence, the periodicity is expanded and the outer structure of the IDA is practically a part of the periodic array. The better CD uniformity can be obtained by adding three assistant features which generate an equal intensity distributions for the complete finger pattern. Considering a mask optimization of the outer structures would also be feasible. However, due to the strong impact of the gap between mask and wafer at contact lithography it is not practicable. The better choice is to create the same intensity distribution for all finger structures. With the introduction of the assistant features large areas with electrode gap sizes in the sub 100 nm region are demonstrated.

Hybrid macro-micro fluidics system for a chip-based biosensor

NASA Astrophysics Data System (ADS)

Tamanaha, C. R.; Whitman, L. J.; Colton, R. J.

2002-03-01

We describe the engineering of a hybrid fluidics platform for a chip-based biosensor system that combines high-performance microfluidics components with powerful, yet compact, millimeter-scale pump and valve actuators. The microfluidics system includes channels, valveless diffuser-based pumps, and pinch-valves that are cast into a poly(dimethylsiloxane) (PDMS) membrane and packaged along with the sensor chip into a palm-sized plastic cartridge. The microfluidics are driven by pump and valve actuators contained in an external unit (with a volume ~30 cm3) that interfaces kinematically with the PDMS microelements on the cartridge. The pump actuator is a simple-lever, flexure-hinge displacement amplifier that increases the motion of a piezoelectric stack. The valve actuators are an array of cantilevers operated by shape memory alloy wires. All components can be fabricated without the need for complex lithography or micromachining, and can be used with fluids containing micron-sized particulates. Prototypes have been modeled and tested to ensure the delivery of microliter volumes of fluid and the even dispersion of reagents over the chip sensing elements. With this hybrid approach to the fluidics system, the biochemical assay benefits from the many advantages of microfluidics yet we avoid the complexity and unknown reliability of immature microactuator technologies.

Superhydrophilic nanopillar-structured quartz surfaces for the prevention of biofilm formation in optical devices

NASA Astrophysics Data System (ADS)

Han, Soo; Ji, Seungmuk; Abdullah, Abdullah; Kim, Duckil; Lim, Hyuneui; Lee, Donghyun

2018-01-01

Bacterial biofilm formation on optical devices such as contact lenses, optical glasses, endoscopic devices, and microscopic slides and lenses are major concerns in the field of medicine and biomedical engineering. To solve these problems, here we present the first report of superhydrophilic transparent nanopillar-structured surfaces with bactericidal properties. To construct bactericidal surfaces, we imitated a topological mechanism found in nature in which nanopillar-structured surfaces cause a mechanical disruption of the outer cell membranes of bacteria, resulting in bacterial cell death. We used nanosphere lithography to fabricate nanopillars with various sharpnesses and heights on a quartz substrate. Water contact angle and light reflectance measurements revealed superhydrophilic, antifogging and antireflective properties, which are important for use in optical devices. To determine bactericidal efficiency, the fabricated surfaces were incubated and tested against two Gram-negative bacteria associated with biofilm formation and various diseases in humans, Pseudomonas aeruginosa and Escherichia coli. The highest bactericidal activity was achieved with nanopillars that measured 300 nm in height and 10 nm in apex diameter. Quartz substrates patterned with such nanopillars killed ∼38,000 P. aeruginosa and ∼27,000 E. coli cells cm-2 min-1, respectively. Thus, the newly designed nanopillar-structured bactericidal surfaces are suitable for use in the development of superhydrophilic and transparent optical devices.

Analytical treatment of the deformation behavior of extreme-ultraviolet-lithography masks during electrostatic chucking

NASA Astrophysics Data System (ADS)

Brandstetter, Gerd; Govindjee, Sanjay

2012-10-01

A new analytical approach is presented to predict mask deformation during electrostatic chucking in next-generation extreme-ultraviolet-lithography. Given an arbitrary profile measurement of the mask and chuck nonflatness, this method has been developed as an alternative to time-consuming finite element simulations for overlay error correction algorithms. We consider the feature transfer of each harmonic component in the profile shapes via linear elasticity theory and demonstrate analytically how high spatial frequencies are filtered. The method is compared to presumably more accurate finite element simulations and has been tested successfully in an overlay error compensation experiment, where the residual error y-component could be reduced by a factor of 2. As a side outcome, the formulation provides a tool to estimate the critical pin-size and -pitch such that the distortion on the mask front-side remains within given tolerances. We find for a numerical example that pin-pitches of less than 5 mm will result in a mask pattern distortion of less than 1 nm if the chucking pressure is below 30 kPa.

Colloidal lithography with electrochemical nickel deposition as a unique method for improved silver decorated nanocavities in SERS applications

NASA Astrophysics Data System (ADS)

Petruš, Ondrej; Oriňak, Andrej; Oriňaková, Renáta; Orságová Králová, Zuzana; Múdra, Erika; Kupková, Miriam; Kovaľ, Karol

2017-11-01

Two types of metallised nanocavities (single and hybrid) were fabricated by colloid lithography followed by electrochemical deposition of Ni and subsequently Ag layers. Introductory Ni deposition step iniciates more homogenous decoration of nanocavities with Ag nanoparticles. Silver nanocavity decoration has been so performed with lower nucleation rate and with Ag nanoparticles homogeinity increase. By this, two step Ni and Ag deposition trough polystyrene nanospheres (100, 300, 500, 700, 900 nm), the various Ag surfaces were obtained. Ni layer formation in the first step of deposition enabled more precise controlling of Ag film deposition and thus final Ag surface morphology. Prepared substrates were tested as active surfaces in SERS application. The best SERS signal enhancement was observed at 500 nm Ag nanocavities with normalised thickness Ni layer ∼0.5. Enhancement factor has been established at value 1.078 × 1010; time stability was determined within 13 weeks; charge distribution at nanocavity Ag surfaces as well as reflection spectra were calculated by FDTD method. Newly prepared nanocavity surface can be applied in SERS analysis, predominantly.

Nanomesh of Cu fabricated by combining nanosphere lithography and high power pulsed magnetron sputtering and a preliminary study about its function

NASA Astrophysics Data System (ADS)

Xie, Wanchuan; Chen, Jiang; Jiang, Lang; Yang, Ping; Sun, Hong; Huang, Nan

2013-10-01

The Cu nanomesh was obtained by a combination of nanosphere lithography (NSL) and high power pulsed magnetron sputtering (HiPPMS). A deposition mask was formed on TiO2 substrates by the self-assembly of polystyrene latex spheres with a diameter of 1 μm, then Cu nanomesh structure was produced on the substrate using sputtering. The structures were investigated by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The results show the increase of temperature of the polystyrene mask caused by the thermal radiation from the target and the bombardment of sputtering particles would affect the quality of the final nanopattern. The tests of photocatalytic degradation, platelet adhesion and human umbilical artery smooth muscle cells (HUASMCs) culture show Cu deposition could promote the photocatalytic efficiency of TiO2, affect platelet adhesion and inhibit smooth muscle cell adhesion and proliferation. It is highlighted that these findings may serve as a guide for the research of multifunctional surface structure.

Enhancement of light output power of GaN-based light-emitting diodes with photonic quasi-crystal patterned on p-GaN surface and n-side sidewall roughing

PubMed Central

2013-01-01

In this paper, GaN-based light-emitting diodes (LEDs) with photonic quasi-crystal (PQC) structure on p-GaN surface and n-side roughing by nano-imprint lithography are fabricated and investigated. At an injection current of 20 mA, the LED with PQC structure on p-GaN surface and n-side roughing increased the light output power of the InGaN/GaN multiple quantum well LEDs by a factor of 1.42, and the wall-plug efficiency is 26% higher than the conventional GaN-based LED type. After 500-h life test (55°C/50 mA), it was found that the normalized output power of GaN-based LED with PQC structure on p-GaN surface and n-side roughing only decreased by 6%. These results offer promising potential to enhance the light output powers of commercial light-emitting devices using the technique of nano-imprint lithography. PMID:23683526

Radiation hardness of molybdenum silicon multilayers designed for use in a soft-x-ray projection lithography system.

PubMed

Gaines, D P; Spitzer, R C; Ceglio, N M; Krumrey, M; Ulm, G

1993-12-01

A molybdenum silicon multilayer is irradiated with 13.4-nm radiation to investigate changes in multilayer performance under simulated soft-x-ray projection lithography (SXPL) conditions. The wiggler-undulator at the Berlin electron storage ring BESSY is used as a quasi-monochromatic source of calculable spectral radiant intensity and is configured to simulate an incident SXPL x-ray spectrum. The test multilayer receives a radiant exposure of 240 J/mm(2) in an exposure lasting 8.9 h. The corresponding average incident power density is 7.5 mW/mm(2). The absorbed dose of 7.8 × 10(10) J/kg (7.8 × 10(12) rad) is equivalent to 1.2 times the dose that would be absorbed by a multilayer coating on the first imaging optic in a hypothetical SXPL system during 1 year of operation. Surface temperature increases do not exceed 2 °C during the exposure. Normal-incidence reflectance measurements at λ(0) = 13.4 nm performed before radiation exposure are in agreement with measurements performed after the exposure, indicating that no sign icant damage had occurred.

Diffractive element in extreme-UV lithography condenser

DOEpatents

Sweatt, William C.; Ray-Chaudhuri, Avijit

2001-01-01

Condensers having a mirror with a diffraction grating in projection lithography using extreme ultra-violet significantly enhances critical dimension control. The diffraction grating has the effect of smoothing the illumination at the camera's entrance pupil with minimum light loss. Modeling suggests that critical dimension control for 100 nm features can be improved from 3 nm to less than about 0.5 nm.

Diffractive element in extreme-UV lithography condenser

DOEpatents

Sweatt, William C.; Ray-Chaudhurl, Avijit K.

2000-01-01

Condensers having a mirror with a diffraction grating in projection lithography using extreme ultra-violet significantly enhances critical dimension control. The diffraction grating has the effect of smoothing the illumination at the camera's entrance pupil with minimum light loss. Modeling suggests that critical dimension control for 100 nm features can be improved from 3 nm to less than about 0.5 nm.

Gyroscope and Micromirror Design Using Vertical-Axis CMOS-MEMS Actuation and Sensing

DTIC Science & Technology

2002-01-01

Interference pattern around the upper anchor (each fringe occurs at 310 nm vertical displacement...described above require extra lithography step(s) other than standard CMOS lithography steps and/or deposition of structural and sacrificial materials...Instruments’ dig- ital mirror device ( DMD ) [43]. The aluminum thin-film technology with vertical parallel- plate actuation has difficulty in achieving

Method to create gradient index in a polymer

DOEpatents

Dirk, Shawn M; Johnson, Ross Stefan; Boye, Robert; Descour, Michael R; Sweatt, William C; Wheeler, David R; Kaehr, Bryan James

2014-10-14

Novel photo-writable and thermally switchable polymeric materials exhibit a refractive index change of .DELTA.n.gtoreq.1.0 when exposed to UV light or heat. For example, lithography can be used to convert a non-conjugated precursor polymer to a conjugated polymer having a higher index-of-refraction. Further, two-photon lithography can be used to pattern high-spatial frequency structures.

Antenna Solar Energy to Electricity Converter (ASETEC)

DTIC Science & Technology

1989-11-01

radiation damage • x-ray masks: all aspects • synchrotron lithography • high brightness compact sources • x-ray lithography system considerations...IB.\\VAlmaden Research Center Cochairs: Daryl Ann Doane, DAD Technologies, Inc.; Elsa Reichmanis, AT&T Bell Laboratories This conferenc’.’ is a...Philips Research- Laboratories/Signetics Corporation DiaSY Nyyssonen, CD Metrology, Inc. Victor Pol, - AT&T Bell Laboratories Elsa Reichmanis

Imprint lithography: lab curiosity or the real NGL

NASA Astrophysics Data System (ADS)

Resnick, Douglas J.; Dauksher, William J.; Mancini, David P.; Nordquist, Kevin J.; Bailey, Todd C.; Johnson, Stephen C.; Stacey, Nicholas A.; Ekerdt, John G.; Willson, C. Grant; Sreenivasan, S. V.; Schumaker, Norman E.

2003-06-01

The escalating cost for Next Generation Lithography (NGL) tools is driven in part by the need for complex sources and optics. The cost for a single NGL tool could exceed $50M in the next few years, a prohibitive number for many companies. As a result, several researchers are looking at low cost alternative methods for printing sub-100 nm features. In the mid-1990s, several resarech groups started investigating different methods for imprinting small features. Many of these methods, although very effective at printing small features across an entire wafer, are limited in their ability to do precise overlay. In 1999, Willson and Sreenivasan discovered that imprinting could be done at low pressures and at room temperatures by using low viscosity UV curable monomers. The technology is typically referred to as Step and Flash Imprint Lithography. The use of a quartz template enabled the photocuring process to occur and also opened up the potential for optical alignment of teh wafer and template. This paper traces the development of nanoimprint lithography and addresses the issues that must be solved if this type of technology is to be applied to high-density silicon integrated circuitry.

Triple/quadruple patterning layout decomposition via novel linear programming and iterative rounding

NASA Astrophysics Data System (ADS)

Lin, Yibo; Xu, Xiaoqing; Yu, Bei; Baldick, Ross; Pan, David Z.

2016-03-01

As feature size of the semiconductor technology scales down to 10nm and beyond, multiple patterning lithography (MPL) has become one of the most practical candidates for lithography, along with other emerging technologies such as extreme ultraviolet lithography (EUVL), e-beam lithography (EBL) and directed self assembly (DSA). Due to the delay of EUVL and EBL, triple and even quadruple patterning are considered to be used for lower metal and contact layers with tight pitches. In the process of MPL, layout decomposition is the key design stage, where a layout is split into various parts and each part is manufactured through a separate mask. For metal layers, stitching may be allowed to resolve conflicts, while it is forbidden for contact and via layers. In this paper, we focus on the application of layout decomposition where stitching is not allowed such as for contact and via layers. We propose a linear programming and iterative rounding (LPIR) solving technique to reduce the number of non-integers in the LP relaxation problem. Experimental results show that the proposed algorithms can provide high quality decomposition solutions efficiently while introducing as few conflicts as possible.

Effect of wafer geometry on lithography chucking processes

NASA Astrophysics Data System (ADS)

Turner, Kevin T.; Sinha, Jaydeep K.

2015-03-01

Wafer flatness during exposure in lithography tools is critical and is becoming more important as feature sizes in devices shrink. While chucks are used to support and flatten the wafer during exposure, it is essential that wafer geometry be controlled as well. Thickness variations of the wafer and high-frequency wafer shape components can lead to poor flatness of the chucked wafer and ultimately patterning problems, such as defocus errors. The objective of this work is to understand how process-induced wafer geometry, resulting from deposited films with non-uniform stress, can lead to high-frequency wafer shape variations that prevent complete chucking in lithography scanners. In this paper, we discuss both the acceptable limits of wafer shape that permit complete chucking to be achieved, and how non-uniform residual stresses in films, either due to patterning or process non-uniformity, can induce high spatial frequency wafer shape components that prevent chucking. This paper describes mechanics models that relate non-uniform film stress to wafer shape and presents results for two example cases. The models and results can be used as a basis for establishing control strategies for managing process-induced wafer geometry in order to avoid wafer flatness-induced errors in lithography processes.

A study of an alignment-less lithography method as an educational resource

NASA Astrophysics Data System (ADS)

Kai, Kazuho; Shiota, Koki; Nagaoka, Shiro; Mahmood, Mohamad Rusop Bin Haji; Kawai, Akira

2016-07-01

A simplification of the lithography process was studied. The simplification method of photolithography, named "alignment-less lithography" was proposed by omitting the photomask alignment process in photolithography process using mechanically aligned photomasks and substrate by using a simple jig on which countersinks were formed. Photomasks made of glass and the photomasks made of transparent plastic sheets were prepared for the process. As the result, approximately 5µm in the case of the glass mask, and 20µm in the case of the OHP mask were obtained with repetitive accuracies, respectively. It was confirmed that the alignment-less lithography method was successful. The possibility of the application to an educational program, such as a heuristic for solving problems was suggested using the method with the OHP mask. The nMOS FET fabrication process was successfully demonstrated using this method. The feasibility of this process was confirmed. It is expected that a totally simplified device fabrication process can be achievable when combined with other simplifications, such ass the simplified impurity diffusion processes using PSG and BSG thin film as diffusion source prepared by the Sol-Gel material under normal air environment.

Maskless EUV lithography: an already difficult technology made even more complicated?

NASA Astrophysics Data System (ADS)

Chen, Yijian

2012-03-01

In this paper, we present the research progress made in maskless EUV lithography and discuss the emerging opportunities for this disruptive technology. It will be shown nanomirrors based maskless approach is one path to costeffective and defect-free EUV lithography, rather than making it even more complicated. The focus of our work is to optimize the existing vertical comb process and scale down the mirror size from several microns to sub-micron regime. The nanomirror device scaling, system configuration, and design issues will be addressed. We also report our theoretical and simulation study of reflective EUV nanomirror based imaging behavior. Dense line/space patterns are formed with an EUV nanomirror array by assigning a phase shift of π to neighboring nanomirrors. Our simulation results show that phase/intensity imbalance is an inherent characteristic of maskless EUV lithography while it only poses a manageable challenge to CD control and process window. The wafer scan and EUV laser jitter induced image blur phenomenon is discussed and a blurred imaging theory is constructed. This blur effect is found to degrade the image contrast at a level that mainly depends on the wafer scan speed.

Nearly amorphous Mo-N gratings for ultimate resolution in extreme ultraviolet interference lithography.

PubMed

Wang, L; Kirk, E; Wäckerlin, C; Schneider, C W; Hojeij, M; Gobrecht, J; Ekinci, Y

2014-06-13

We present fabrication and characterization of high-resolution and nearly amorphous Mo1 - xNx transmission gratings and their use as masks for extreme ultraviolet (EUV) interference lithography. During sputter deposition of Mo, nitrogen is incorporated into the film by addition of N2 to the Ar sputter gas, leading to suppression of Mo grain growth and resulting in smooth and homogeneous thin films with a negligible grain size. The obtained Mo0.8N0.2 thin films, as determined by x-ray photoelectron spectroscopy, are characterized to be nearly amorphous using x-ray diffraction. We demonstrate a greatly reduced Mo0.8N0.2 grating line edge roughness compared with pure Mo grating structures after e-beam lithography and plasma dry etching. The amorphous Mo0.8N0.2 thin films retain, to a large extent, the benefits of Mo as a phase grating material for EUV wavelengths, providing great advantages for fabrication of highly efficient diffraction gratings with extremely low roughness. Using these grating masks, well-resolved dense lines down to 8 nm half-pitch are fabricated with EUV interference lithography.

Engineers are from PDMS-land, Biologists are from Polystyrenia.

PubMed

Berthier, Erwin; Young, Edmond W K; Beebe, David

2012-04-07

As the integration of microfluidics into cell biology research proceeds at an ever-increasing pace, a critical question for those working at the interface of both disciplines is which device material to use for a given application. While PDMS and soft lithography methods offer the engineer rapid prototyping capabilities, PDMS as a material has characteristics that have known adverse effects on cell-based experiments. In contrast, while polystyrene (PS), the most commonly used thermoplastic for laboratory cultureware, has provided decades of grounded and validated research conclusions in cell behavior and function, PS as a material has posed significant challenges in microfabrication. These competing issues have forced microfluidics engineers and biologists to make compromises in how they approach specific research questions, and furthermore, have attenuated the impact of microfluidics on biological research. In this review, we provide a comparison of the attributes of PDMS and PS, and discuss reasons for their popularity in their respective fields. We provide a critical evaluation of the strengths and limitations of PDMS and PS in relation to the advancement and future impact on microfluidic cell-based studies and applications. We believe that engineers have a responsibility to overcome any challenges associated with microfabrication, whether with PS or other materials, and that engineers should provide options and solutions that assist biologists in their experimental design. Our goal is not to advocate for any specific material, but provide guidelines for researchers who desire to choose the most suitable material for their application, and suggest important research directions for engineers working at the interface between microfabrication technology and biological application. This journal is © The Royal Society of Chemistry 2012

Lithography-based fabrication of nanopore arrays in freestanding SiN and graphene membranes

NASA Astrophysics Data System (ADS)

Verschueren, Daniel V.; Yang, Wayne; Dekker, Cees

2018-04-01

We report a simple and scalable technique for the fabrication of nanopore arrays on freestanding SiN and graphene membranes based on electron-beam lithography and reactive ion etching. By controlling the dose of the single-shot electron-beam exposure, circular nanopores of any size down to 16 nm in diameter can be fabricated in both materials at high accuracy and precision. We demonstrate the sensing capabilities of these nanopores by translocating dsDNA through pores fabricated using this method, and find signal-to-noise characteristics on par with transmission-electron-microscope-drilled nanopores. This versatile lithography-based approach allows for the high-throughput manufacturing of nanopores and can in principle be used on any substrate, in particular membranes made out of transferable two-dimensional materials.

Direct-write maskless lithography using patterned oxidation of Si-substrate Induced by femtosecond laser pulses

NASA Astrophysics Data System (ADS)

Kiani, Amirkianoosh; Venkatakrishnan, Krishnan; Tan, Bo

2013-03-01

In this study we report a new method for direct-write maskless lithography using oxidized silicon layer induced by high repetition (MHz) ultrafast (femtosecond) laser pulses under ambient condition. The induced thin layer of predetermined pattern can act as an etch stop during etching process in alkaline etchants such as KOH. The proposed method can be leading to promising solutions for direct-write maskless lithography technique since the proposed method offers a higher degree of flexibility and reduced time and cost of fabrication which makes it particularly appropriate for rapid prototyping and custom scale manufacturing. A Scanning Electron Microscope (SEM), Micro-Raman, Energy Dispersive X-ray (EDX), optical microscope and X-ray diffraction spectroscopy (XRD) were used to evaluate the quality of oxidized layer induced by laser pulses.

150-nm generation lithography equipment

NASA Astrophysics Data System (ADS)

Deguchi, Nobuyoshi; Uzawa, Shigeyuki

1999-07-01

Lithography by step-and-scan exposure is expected to be the mainstream for semiconductor manufacturing below 180 nm resolution patterns. We have developed a scanner for 150 nm features on either 200 mm or 300 mm wafers. For this system, the synchronous stage system has been redesigned which makes it possible to improve imaging performance and overlay accuracy. A new 300 mm wafer stage enhances productivity while weighting almost the same as the stage for 200 mm wafers. The mainbody mechanical frame incorporates reactive force receiver system to counter the inertial energy and vibrational issues associated with high speed wafer and reticle stage scanning. This report outlines the total system design, new technologies and performance data of the Cannon FPA-5000ES2 step-and-scan exposure tool developed for the 150 nm generation lithography.

Driving imaging and overlay performance to the limits with advanced lithography optimization

NASA Astrophysics Data System (ADS)

Mulkens, Jan; Finders, Jo; van der Laan, Hans; Hinnen, Paul; Kubis, Michael; Beems, Marcel

2012-03-01

Immersion lithography is being extended to 22-nm and even below. Next to generic scanner system improvements, application specific solutions are needed to follow the requirements for CD control and overlay. Starting from the performance budgets, this paper discusses how to improve (in volume manufacturing environment) CDU towards 1-nm and overlay towards 3-nm. The improvements are based on deploying the actuator capabilities of the immersion scanner. The latest generation immersion scanners have extended the correction capabilities for overlay and imaging, offering freeform adjustments of lens, illuminator and wafer grid. In order to determine the needed adjustments the recipe generation per user application is based on a combination wafer metrology data and computational lithography methods. For overlay, focus and CD metrology we use an angle resolved optical scatterometer.

Investigation of pattern transfer to piezoelectric jetted polymer using roll-to-roll nanoimprint lithography

NASA Astrophysics Data System (ADS)

Menezes, Shannon John

Nanoimprint Lithography (NIL) has existed since the mid 1990s as a proven concept of creating micro- and nanostructures using direct mechanical pattern transfer. Initially seen as a viable option to replace conventional lithography methods, the lack of technology to support large-scale manufacturing using NIL has motivated researchers to explore the application of NIL to create a better, more cost-efficient process with the ability to integrate NIL into a mass manufacturing system. One such method is the roll-to-roll process, similar to that used in printing presses of newspapers and plastics. This thesis is an investigation to characterize polymer deposition using a piezoelectric jetting head and attempt to create micro- and nanostructures on the polymer using R2RNIL technique.

Sub-micron lines patterning into silica using water developable chitosan bioresist films for eco-friendly positive tone e-beam and UV lithography

NASA Astrophysics Data System (ADS)

Caillau, Mathieu; Chevalier, Céline; Crémillieu, Pierre; Delair, Thierry; Soppera, Olivier; Leuschel, Benjamin; Ray, Cédric; Moulin, Christophe; Jonin, Christian; Benichou, Emmanuel; Brevet, Pierre-François; Yeromonahos, Christelle; Laurenceau, Emmanuelle; Chevolot, Yann; Leclercq, Jean-Louis

2018-03-01

Biopolymers represent natural, renewable and abundant materials. Their use is steadily growing in various areas (food, health, building …) but, in lithography, despite some works, resists, solvents and developers are still oil-based and hazardous chemicals. In this work, we replaced synthetic resist by chitosan, a natural, abundant and hydrophilic polysaccharide. High resolution sub-micron patterns were obtained through chitosan films as water developable, chemically unmodified, positive tone mask resist for an eco-friendly electron beam and deep-UV (193 nm) lithography process. Sub-micron patterns were also successfully obtained using a 248 nm photomasker thanks to the addition of biosourced photoactivator, riboflavin. Patterns were then transferred by plasma etching into silica even for high resolution patterns.

Resist Parameter Extraction from Line-and-Space Patterns of Chemically Amplified Resist for Extreme Ultraviolet Lithography

NASA Astrophysics Data System (ADS)

Kozawa, Takahiro; Oizumi, Hiroaki; Itani, Toshiro; Tagawa, Seiichi

2010-11-01

The development of extreme ultraviolet (EUV) lithography has progressed owing to worldwide effort. As the development status of EUV lithography approaches the requirements for the high-volume production of semiconductor devices with a minimum line width of 22 nm, the extraction of resist parameters becomes increasingly important from the viewpoints of the accurate evaluation of resist materials for resist screening and the accurate process simulation for process and mask designs. In this study, we demonstrated that resist parameters (namely, quencher concentration, acid diffusion constant, proportionality constant of line edge roughness, and dissolution point) can be extracted from the scanning electron microscopy (SEM) images of patterned resists without the knowledge on the details of resist contents using two types of latest EUV resist.

Understanding overlay signatures using machine learning on non-lithography context information

NASA Astrophysics Data System (ADS)

Overcast, Marshall; Mellegaard, Corey; Daniel, David; Habets, Boris; Erley, Georg; Guhlemann, Steffen; Thrun, Xaver; Buhl, Stefan; Tottewitz, Steven

2018-03-01

Overlay errors between two layers can be caused by non-lithography processes. While these errors can be compensated by the run-to-run system, such process and tool signatures are not always stable. In order to monitor the impact of non-lithography context on overlay at regular intervals, a systematic approach is needed. Using various machine learning techniques, significant context parameters that relate to deviating overlay signatures are automatically identified. Once the most influential context parameters are found, a run-to-run simulation is performed to see how much improvement can be obtained. The resulting analysis shows good potential for reducing the influence of hidden context parameters on overlay performance. Non-lithographic contexts are significant contributors, and their automatic detection and classification will enable the overlay roadmap, given the corresponding control capabilities.

Fabrication of a negative PMMA master mold for soft-lithography by MeV ion beam lithography

NASA Astrophysics Data System (ADS)

Puttaraksa, Nitipon; Unai, Somrit; Rhodes, Michael W.; Singkarat, Kanda; Whitlow, Harry J.; Singkarat, Somsorn

2012-02-01

In this study, poly(methyl methacrylate) (PMMA) was investigated as a negative resist by irradiation with a high-fluence 2 MeV proton beam. The beam from a 1.7 MV Tandetron accelerator at the Plasma and Beam Physics Research Facility (PBP) of Chiang Mai University is shaped by a pair of computer-controlled L-shaped apertures which are used to expose rectangular pattern elements with 1-1000 μm side length. Repeated exposure of rectangular pattern elements allows a complex pattern to be built up. After subsequent development, the negative PMMA microstructure was used as a master mold for casting poly(dimethylsiloxane) (PDMS) following a standard soft-lithography process. The PDMS chip fabricated by this technique was demonstrated to be a microfluidic device.

Wiring up pre-characterized single-photon emitters by laser lithography

NASA Astrophysics Data System (ADS)

Shi, Q.; Sontheimer, B.; Nikolay, N.; Schell, A. W.; Fischer, J.; Naber, A.; Benson, O.; Wegener, M.

2016-08-01

Future quantum optical chips will likely be hybrid in nature and include many single-photon emitters, waveguides, filters, as well as single-photon detectors. Here, we introduce a scalable optical localization-selection-lithography procedure for wiring up a large number of single-photon emitters via polymeric photonic wire bonds in three dimensions. First, we localize and characterize nitrogen vacancies in nanodiamonds inside a solid photoresist exhibiting low background fluorescence. Next, without intermediate steps and using the same optical instrument, we perform aligned three-dimensional laser lithography. As a proof of concept, we design, fabricate, and characterize three-dimensional functional waveguide elements on an optical chip. Each element consists of one single-photon emitter centered in a crossed-arc waveguide configuration, allowing for integrated optical excitation and efficient background suppression at the same time.

X-ray lithography source

DOEpatents

Piestrup, M.A.; Boyers, D.G.; Pincus, C.

1991-12-31

A high-intensity, inexpensive X-ray source for X-ray lithography for the production of integrated circuits is disclosed. Foil stacks are bombarded with a high-energy electron beam of 25 to 250 MeV to produce a flux of soft X-rays of 500 eV to 3 keV. Methods of increasing the total X-ray power and making the cross section of the X-ray beam uniform are described. Methods of obtaining the desired X-ray-beam field size, optimum frequency spectrum and eliminating the neutron flux are all described. A method of obtaining a plurality of station operation is also described which makes the process more efficient and economical. The satisfying of these issues makes transition radiation an excellent moderate-priced X-ray source for lithography. 26 figures.

Fabrication of sub-12 nm thick silicon nanowires by processing scanning probe lithography masks

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

Kyoung Ryu, Yu; Garcia, Ricardo, E-mail: r.garcia@csic.es; Aitor Postigo, Pablo

2014-06-02

Silicon nanowires are key elements to fabricate very sensitive mechanical and electronic devices. We provide a method to fabricate sub-12 nm silicon nanowires in thickness by combining oxidation scanning probe lithography and anisotropic dry etching. Extremely thin oxide masks (0.3–1.1 nm) are transferred into nanowires of 2–12 nm in thickness. The width ratio between the mask and the silicon nanowire is close to one which implies that the nanowire width is controlled by the feature size of the nanolithography. This method enables the fabrication of very small single silicon nanowires with cross-sections below 100 nm{sup 2}. Those values are the smallest obtained withmore » a top-down lithography method.« less

Fabrication of superconducting nanowire single-photon detectors by nonlinear femtosecond optical lithography

NASA Astrophysics Data System (ADS)

Minaev, N. V.; Tarkhov, M. A.; Dudova, D. S.; Timashev, P. S.; Chichkov, B. N.; Bagratashvili, V. N.

2018-02-01

This paper describes a new approach to the fabrication of superconducting nanowire single-photon detectors from ultrathin NbN films on SiO2 substrates. The technology is based on nonlinear femtosecond optical lithography and includes direct formation of the sensitive element of the detector (the meander) through femtosecond laser exposure of the polymethyl methacrylate resist at a wavelength of 525 nm and subsequent removal of NbN using plasma-chemical etching. The nonlinear femtosecond optical lithography method allows the formation of planar structures with a spatial resolution of ~50 nm. These structures were used to fabricate single-photon superconducting detectors with quantum efficiency no worse than 8% at a wavelength of 1310 nm and dark count rate of 10 s-1 at liquid helium temperature.

Challenges of anamorphic high-NA lithography and mask making

NASA Astrophysics Data System (ADS)

Hsu, Stephen D.; Liu, Jingjing

2017-06-01

Chip makers are actively working on the adoption of 0.33 numerical aperture (NA) EUV scanners for the 7-nm and 5-nm nodes (B. Turko, S. L. Carson, A. Lio, T. Liang, M. Phillips, et al., in `Proc. SPIE9776, Extreme Ultraviolet (EUV) Lithography VII', vol. 977602 (2016) doi: 10.1117/12.2225014; A. Lio, in `Proc. SPIE9776, Extreme Ultraviolet (EUV) Lithography VII', vol. 97760V (2016) doi: 10.1117/12.2225017). In the meantime, leading foundries and integrated device manufacturers are starting to investigate patterning options beyond the 5-nm node (O. Wood, S. Raghunathan, P. Mangat, V. Philipsen, V. Luong, et al., in `Proc. SPIE. 9422, Extreme Ultraviolet (EUV) Lithography VI', vol. 94220I (2015) doi: 10.1117/12.2085022). To minimize the cost and process complexity of multiple patterning beyond the 5-nm node, EUV high-NA single-exposure patterning is a preferred method over EUV double patterning (O. Wood, S. Raghunathan, P. Mangat, V. Philipsen, V. Luong, et al., in `Proc. SPIE. 9422, Extreme Ultraviolet (EUV) Lithography VI', vol. 94220I (2015) doi: 10.1117/12.2085022; J. van Schoot, K. van Ingen Schenau, G. Bottiglieri, K. Troost, J. Zimmerman, et al., `Proc. SPIE. 9776, Extreme Ultraviolet (EUV) Lithography VII', vol. 97761I (2016) doi: 10.1117/12.2220150). The EUV high-NA scanner equipped with a projection lens of 0.55 NA is designed to support resolutions below 10 nm. The high-NA system is beneficial for enhancing resolution, minimizing mask proximity correction bias, improving normalized image log slope (NILS), and controlling CD uniformity (CDU). However, increasing NA from 0.33 to 0.55 reduces the depth of focus (DOF) significantly. Therefore, the source mask optimization (SMO) with sub-resolution assist features (SRAFs) are needed to increase DOF to meet the demanding full chip process control requirements (S. Hsu, R. Howell, J. Jia, H.-Y. Liu, K. Gronlund, et al., EUV `Proc. SPIE9048, Extreme Ultraviolet (EUV) Lithography VI', (2015) doi: 10.1117/12.2086074). To ensure no assist feature printing, the assist feature sizes need to be scaled with λ/NA. The extremely small SRAF width (below 25 nm on the reticle) is difficult to fabricate across the full reticle. In this paper, we introduce an innovative `attenuated SRAF' to improve SRAF manufacturability and still maintain the process window benefit. A new mask fabrication process is proposed to use existing mask-making capability to manufacture the attenuated SRAFs. The high-NA EUV system utilizes anamorphic reduction; 4× in the horizontal (slit) direction and 8× in the vertical (scanning) direction (J. van Schoot, K. van Ingen Schenau, G. Bottiglieri, K. Troost, J. Zimmerman, et al., `Proc. SPIE. 9776, Extreme Ultraviolet (EUV) Lithography VII', vol. 97761I (2016) doi: 10.1117/12.2220150; B. Kneer, S. Migura, W. Kaiser, J. T. Neumann, J. van Schoot, in `Proc. SPIE9422, Extreme Ultraviolet (EUV) Lithography VI', vol. 94221G (2015) doi: 10.1117/12.2175488). For an anamorphic system, the magnification has an angular dependency, and thus, familiar mask specifications such as mask error factor (MEF) need to be redefined. Similarly, mask-manufacturing rule check (MRC) needs to consider feature orientation.

Hybrid strategies for nanolithography and chemical patterning

NASA Astrophysics Data System (ADS)

Srinivasan, Charan

Remarkable technological advances in photolithography have extended patterning to the sub-50-nm regime. However, because photolithography is a top-down approach, it faces substantial technological and economic challenges in maintaining the downward scaling trends of feature sizes below 30 nm. Concurrently, fundamental research on chemical self-assembly has enabled the path to access molecular length scales. The key to the success of photolithography is its inherent economies of scale, which justify the large capital investment for its implementation. In this thesis research, top-down and bottom-up approaches have been combined synergistically, and these hybrid strategies have been employed in applications that do not have the economies of scale found in semiconductor chip manufacturing. The specific instances of techniques developed here include molecular-ruler lithography and a series of nanoscale chemical patterning methods. Molecular-ruler lithography utilizes self-assembled multilayered films as a sidewall spacer on initial photolithographically patterned gold features (parent) to place a second-generation feature (daughter) in precise proximity to the parent. The parent-daughter separation, which is on the nanometer length scale, is defined by the thickness of the molecular-ruler resist. Analogous to protocols followed in industry to evaluate lithographic performance, electrical test-pad structures were designed to interrogate the nanostructures patterned by molecular-ruler nanolithography, failure modes creating electrical shorts were mapped to each lithographic step, and subsequent lithographic optimization was performed to pattern nanoscale devices with excellent electrical performance. The optimized lithographic processes were applied to generate nanoscale devices such as nanowires and thin-film transistors (TFTs). Metallic nanowires were patterned by depositing a tertiary generation material in the nanogap and surrounding micron-scale regions, and then chemically removing the parent and daughter structures selectively. This processing was also performed on silicon-on-insulator substrates and the metallic nanowires were used as a hard mask to transfer the pattern to the single crystalline silicon epilayer resulting in a quaternary generation structure of single-crystalline silicon nanowire field-effect transistors. Additionally, the proof of concept for patterning nanoscale pentacene TFTs utilizing molecular-rulers was demonstrated. For applications in sub-100-nm lithography, the limitations on the relative heights of parent and daughter structures were overcome and processes to integrate molecular-ruler nanolithography with existing complementary metal-oxide-semiconductor (CMOS) processing were developed. Pattern transfer to underlying SiO2 substrates has opened a new avenue of opportunities to apply these nanostructures in nanofluidics and in non-traditional lithography such as imprint lithography. Additionally, the molecular-ruler process has been shown to increase the spatial density of features created by high-resolution techniques such as electron-beam lithography. A limitation of photolithography is its inability to pattern chemical functionality on surfaces. To overcome this limitation, two techniques were developed to extend nanolithography beyond semiconductors and apply them to patterning of self-assembled monolayers. First, a novel bilayer resist was devised to protect and to pattern chemical functionality on surfaces by being able to withstand conditions necessary for both chemical self-assembly and photooxidation of the Au-S bond while not disrupting the preexisting SAM. In addition to photolithography, soft-lithographic approaches such as microcontact printing are often used to create chemical patterns. In this work, a technique for the creation of chemical patterns of inserted molecules with dilute coverages (≤10%) was implemented. As part of the research in chemical patterning, a method for characterizing chemical patterns using scanning electron microscopy has been developed. These tools are the standard for metrology in nanolithography, and thus are readily accessible as our advances in chemical patterning are adopted and applied by the lithography community.

A new storage-ring light source

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

Chao, Alex

2015-06-01

A recently proposed technique in storage ring accelerators is applied to provide potential high-power sources of photon radiation. The technique is based on the steady-state microbunching (SSMB) mechanism. As examples of this application, one may consider a high-power DUV photon source for research in atomic and molecular physics or a high-power EUV radiation source for industrial lithography. A less challenging proof-of-principle test to produce IR radiation using an existing storage ring is also considered.

Application Specific Chemical Information Microprocessor (ASCI mu P)

DTIC Science & Technology

1999-09-30

lithography created channels in polydimethylsiloxane polymer. 1C. Optical micrograph of 100 um line widths using soft lithography Progress has also been made...also collaborated with Dr. Jose Almirall at Florida International University and have accomplished the HPLC method development of explosives detection...analytical materials. We have established the base for LIF electrophoretic chip analysis and similarly for the electrochemcial detection. We have learned the

Vacuum system for room temperature X-ray lithography source (XLS)

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

Schuchman, J.C.

1988-09-30

A prototype room-temperature X-Ray Lithography Source (XLS)was proposed to be built at Brookhaven National Laboratory as part of a technology-transfer- to-American-industry program. The overall machine comprises a full energy linac, a 170 meter long transport line, and a 39 meter circumference storage ring. The scope of this paper will be limited to describing the storage ring vacuum system. (AIP)

Intelligent Luminescence for Communication Display and Identification

DTIC Science & Technology

2007-07-18

34Fabrication of two-dimensional photonic crystals using interference lithography and electrodeposition of CdSe," Appl. Phys. Letts. 79, 3392-3394 (2001). 7...studies were performed on holographically derived structures fonned in SUS by a four-laser beam interference pattern. As shown in Figure 7 a SUS polymer...dielectric material, as patterned by electron-beam lithography , consisting of a periodic dielectric modulation with integrated line, point and

Solid Freeform Fabrication Proceedings -1999

DTIC Science & Technology

1999-08-11

geometry of the stylus. Some geometries cannot be used to acquire data if the part geometry interferes 48 with a feature on the part. Thus, the data...fabrication processing systems such as surface micro- machining and lithography . 63 Conclusion The LCVD system (figure 6) has the versatility and...part, creating STL (STereo Lithography ) or VRML (Virtual Reality Modeling Language) files, slicing them, converting into laser path files, and

Printed Biopolymer-Based Electro-Optic Device Components

DTIC Science & Technology

2013-07-01

devices and fabricated e-beam lithography-based master molds. Printed micro and nanostructures using a newly developed spin-on nanoprinting (SNAP...polymeric materials. Among the natural biopolymers , deoxyribonucleic acid (DNA) is an attractive material which can be used to make electronic and...photonic devices [2, 3]. If patterned on the micro and nanoscale using a soft lithography technique, high quality biodegradable optical devices can be

Vacuum system for room temperature X-ray lithography source (XLS)

NASA Astrophysics Data System (ADS)

Schuchman, J. C.

1988-09-01

A prototype room-temperature X-Ray Lithography Source (XLS)was proposed to be built at Brookhaven National Laboratory as part of a technology-transfer- to-American-industry program. The overall machine comprises a full energy linac, a 170 meter long transport line, and a 39 meter circumference storage ring. The scope of this paper will be limited to describing the storage ring vacuum system. (AIP)

CXRO - Mi-Young Im, Staff Scientist

Science.gov Websites

X-Ray Database Zone Plate Education Nanomagnetism X-Ray Microscopy LDJIM EUV Lithography EUV Mask Publications Contact The Center for X-Ray Optics is a multi-disciplined research group within Lawrence Berkeley -Ray Optics X-Ray Database Nanomagnetism X-Ray Microscopy EUV Lithography EUV Mask Imaging

Double exposure technique for 45nm node and beyond

NASA Astrophysics Data System (ADS)

Hsu, Stephen; Park, Jungchul; Van Den Broeke, Douglas; Chen, J. Fung

2005-11-01

The technical challenges in using F2 lithography for the 45nm node, along with the insurmountable difficulties in EUV lithography, has driven the semiconductor chipmaker into the low k1 lithography era under the pressure of ever decreasing feature sizes. Extending lithography towards lower k1 puts heavy demand on the resolution enhancement technique (RET), exposure tool, and the need for litho friendly design. Hyper numerical aperture (NA) exposure tools, immersion, and double exposure techniques (DET's) are the promising methods to extend lithography manufacturing to the 45nm node at k1 factors below 0.3. Scattering bars (SB's) have become an integral part of the lithography process as chipmakers move to production at ever lower k1 factors. To achieve better critical dimension (CD) control, polarization is applied to enhance the image contrast in the preferential imaging orientation, which increases the risk of SB printability. The optimum SB width is approximately (0.20 ~ 0.25)*(λ/NA). When the SB width becomes less than the exposure wavelength on the 4X mask, Kirchhoff's scalar theory under predicts the SB intensity. The optical weighting factor of the SB increases (Figure 1b) and the SB's become more susceptible to printing. Meanwhile, under hyper NA conditions, the effectiveness of "subresolution" SB's is significantly diminished. A full-sized scattering bars (FSB) scheme becomes necessary. Double exposure methods, such as using ternary 6% attenuated PSM (attPSM) for DDL, are good imaging solutions that can reach and likely go beyond the 45nm node. Today DDL, using binary chrome masks, is capable of printing 65 nm device patterns. In this work, we investigate the use of DET with 6% attPSM masks to target 45nm node device. The SB scalability and printability issues can be taken cared of by using "mutual trimming", i.e., with the combined energy from the two exposures. In this study, we share our findings of using DET to pattern a 45nm node device design with polarization and immersion. We also explore other double patterning methods which in addition to having two exposures, incorporates double coat/developing/etch processing to break the 0.25 k1 barrier.

From powerful research platform for industrial EUV photoresist development, to world record resolution by photolithography: EUV interference lithography at the Paul Scherrer Institute

NASA Astrophysics Data System (ADS)

Buitrago, Elizabeth; Fallica, Roberto; Fan, Daniel; Karim, Waiz; Vockenhuber, Michaela; van Bokhoven, Jeroen A.; Ekinci, Yasin

2016-09-01

Extreme ultraviolet interference lithography (EUV-IL, λ = 13.5 nm) has been shown to be a powerful technique not only for academic, but also for industrial research and development of EUV materials due to its relative simplicity yet record high-resolution patterning capabilities. With EUV-IL, it is possible to pattern high-resolution periodic images to create highly ordered nanostructures that are difficult or time consuming to pattern by electron beam lithography (EBL) yet interesting for a wide range of applications such as catalysis, electronic and photonic devices, and fundamental materials analysis, among others. Here, we will show state-of the-art research performed using the EUV-IL tool at the Swiss Light Source (SLS) synchrotron facility in the Paul Scherrer Institute (PSI). For example, using a grating period doubling method, a diffraction mask capable of patterning a world record in photolithography of 6 nm half-pitch (HP), was produced. In addition to the description of the method, we will give a few examples of applications of the technique. Well-ordered arrays of suspended silicon nanowires down to 6.5 nm linewidths have been fabricated and are to be studied as field effect transistors (FETs) or biosensors, for instance. EUV achromatic Talbot lithography (ATL), another interference scheme that utilizes a single grating, was shown to yield well-defined nanoparticles over large-areas with high uniformity presenting great opportunities in the field of nanocatalysis. EUV-IL is in addition, playing a key role in the future introduction of EUV lithography into high volume manufacturing (HVM) of semiconductor devices for the 7 and 5 nm logic node (16 nm and 13 nm HP, respectively) and beyond while the availability of commercial EUV-tools is still very much limited for research.

450mm wafer patterning with jet and flash imprint lithography

NASA Astrophysics Data System (ADS)

Thompson, Ecron; Hellebrekers, Paul; Hofemann, Paul; LaBrake, Dwayne L.; Resnick, Douglas J.; Sreenivasan, S. V.

2013-09-01

The next step in the evolution of wafer size is 450mm. Any transition in sizing is an enormous task that must account for fabrication space, environmental health and safety concerns, wafer standards, metrology capability, individual process module development and device integration. For 450mm, an aggressive goal of 2018 has been set, with pilot line operation as early as 2016. To address these goals, consortiums have been formed to establish the infrastructure necessary to the transition, with a focus on the development of both process and metrology tools. Central to any process module development, which includes deposition, etch and chemical mechanical polishing is the lithography tool. In order to address the need for early learning and advance process module development, Molecular Imprints Inc. has provided the industry with the first advanced lithography platform, the Imprio® 450, capable of patterning a full 450mm wafer. The Imprio 450 was accepted by Intel at the end of 2012 and is now being used to support the 450mm wafer process development demands as part of a multi-year wafer services contract to facilitate the semiconductor industry's transition to lower cost 450mm wafer production. The Imprio 450 uses a Jet and Flash Imprint Lithography (J-FILTM) process that employs drop dispensing of UV curable resists to assist high resolution patterning for subsequent dry etch pattern transfer. The technology is actively being used to develop solutions for markets including NAND Flash memory, patterned media for hard disk drives and displays. This paper reviews the recent performance of the J-FIL technology (including overlay, throughput and defectivity), mask development improvements provided by Dai Nippon Printing, and the application of the technology to a 450mm lithography platform.

Line-frequency doubling of directed self-assembly patterns for single-digit bit pattern media lithography

NASA Astrophysics Data System (ADS)

Patel, K. C.; Ruiz, R.; Lille, J.; Wan, L.; Dobiz, E.; Gao, H.; Robertson, N.; Albrecht, T. R.

2012-03-01

Directed self-assembly is emerging as a promising technology to define sub-20nm features. However, a straightforward path to scale block copolymer lithography to single-digit fabrication remains challenging given the diverse material properties found in the wide spectrum of self-assembling materials. A vast amount of block copolymer research for industrial applications has been dedicated to polystyrene-b-methyl methacrylate (PS-b-PMMA), a model system that displays multiple properties making it ideal for lithography, but that is limited by a weak interaction parameter that prevents it from scaling to single-digit lithography. Other block copolymer materials have shown scalability to much smaller dimensions, but at the expense of other material properties that could delay their insertion into industrial lithographic processes. We report on a line doubling process applied to block copolymer patterns to double the frequency of PS-b-PMMA line/space features, demonstrating the potential of this technique to reach single-digit lithography. We demonstrate a line-doubling process that starts with directed self-assembly of PS-b-PMMA to define line/space features. This pattern is transferred into an underlying sacrificial hard-mask layer followed by a growth of self-aligned spacers which subsequently serve as hard-masks for transferring the 2x frequency doubled pattern to the underlying substrate. We applied this process to two different block copolymer materials to demonstrate line-space patterns with a half pitch of 11nm and 7nm underscoring the potential to reach single-digit critical dimensions. A subsequent patterning step with perpendicular lines can be used to cut the fine line patterns into a 2-D array of islands suitable for bit patterned media. Several integration challenges such as line width control and line roughness are addressed.

Progress on complementary patterning using plasmon-excited electron beamlets (Conference Presentation)

NASA Astrophysics Data System (ADS)

Du, Zhidong; Chen, Chen; Pan, Liang

2017-04-01

Maskless lithography using parallel electron beamlets is a promising solution for next generation scalable maskless nanolithography. Researchers have focused on this goal but have been unable to find a robust technology to generate and control high-quality electron beamlets with satisfactory brightness and uniformity. In this work, we will aim to address this challenge by developing a revolutionary surface-plasmon-enhanced-photoemission (SPEP) technology to generate massively-parallel electron beamlets for maskless nanolithography. The new technology is built upon our recent breakthroughs in plasmonic lenses, which will be used to excite and focus surface plasmons to generate massively-parallel electron beamlets through photoemission. Specifically, the proposed SPEP device consists of an array of plasmonic lens and electrostatic micro-lens pairs, each pair independently producing an electron beamlet. During lithography, a spatial optical modulator will dynamically project light onto individual plasmonic lenses to control the switching and brightness of electron beamlets. The photons incident onto each plasmonic lens are concentrated into a diffraction-unlimited spot as localized surface plasmons to excite the local electrons to near their vacuum levels. Meanwhile, the electrostatic micro-lens extracts the excited electrons to form a focused beamlet, which can be rastered across a wafer to perform lithography. Studies showed that surface plasmons can enhance the photoemission by orders of magnitudes. This SPEP technology can scale up the maskless lithography process to write at wafers per hour. In this talk, we will report the mechanism of the strong electron-photon couplings and the locally enhanced photoexcitation, design of a SPEP device, overview of our proof-of-concept study, and demonstrated parallel lithography of 20-50 nm features.

Implementation of assist features in EUV lithography

NASA Astrophysics Data System (ADS)

Jiang, Fan; Burkhardt, Martin; Raghunathan, Ananthan; Torres, Andres; Gupta, Rachit; Word, James

2015-03-01

The introduction of EUV lithography will happen at a critical feature pitch which corresponds to a k1 factor of roughly 0.45. While this number seems not very aggressive compared to recent ArF lithography nodes, the number is sufficiently low that the introduction of assist features has to be considered. While the small NA makes the k1 factor larger, the depth of focus still needs to be scaled down with wavelength. However the exposure tool's focus control is not greatly improved over the ArF tools, so other solutions to improve the depth of focus, e.g. SRAFs, are needed. On the other hand, sub-resolution assist features (SRAFs) require very small mask dimensions, which make masks more costly to write and inspect. Another disadvantage of SRAFs is the fact that they may cause pattern-dependent best focus shift due to thick mask effects. Those effects can be predicted, but the shift of best focus and the associated tilt of Bossung curves make the process more difficult to control. We investigate the impact of SRAFs on printing in EUV lithography and evaluate advantages and disadvantages. By using image quality parameters such as best focus (BF), and depth of focus (DOF), respectively with and without SRAFs, we will answer the question if we can gain a net benefit for 1D and 2D patterns by adding SRAFs. SRAFs will only be introduced if any net improvement in process variation (PV) outweighs the additional expense of assist patterning on the mask. In this paper, we investigate the difference in printing behavior of symmetric and asymmetric SRAF placement and whether through slit effect needs to be considered in SRAF placement for EUV lithography.

Interference lithography for optical devices and coatings

NASA Astrophysics Data System (ADS)

Juhl, Abigail Therese

Interference lithography can create large-area, defect-free nanostructures with unique optical properties. In this thesis, interference lithography will be utilized to create photonic crystals for functional devices or coatings. For instance, typical lithographic processing techniques were used to create 1, 2 and 3 dimensional photonic crystals in SU8 photoresist. These structures were in-filled with birefringent liquid crystal to make active devices, and the orientation of the liquid crystal directors within the SU8 matrix was studied. Most of this thesis will be focused on utilizing polymerization induced phase separation as a single-step method for fabrication by interference lithography. For example, layered polymer/nanoparticle composites have been created through the one-step two-beam interference lithographic exposure of a dispersion of 25 and 50 nm silica particles within a photopolymerizable mixture at a wavelength of 532 nm. In the areas of constructive interference, the monomer begins to polymerize via a free-radical process and concurrently the nanoparticles move into the regions of destructive interference. The holographic exposure of the particles within the monomer resin offers a single-step method to anisotropically structure the nanoconstituents within a composite. A one-step holographic exposure was also used to fabricate self-healing coatings that use water from the environment to catalyze polymerization. Polymerization induced phase separation was used to sequester an isocyanate monomer within an acrylate matrix. Due to the periodic modulation of the index of refraction between the monomer and polymer, the coating can reflect a desired wavelength, allowing for tunable coloration. When the coating is scratched, polymerization of the liquid isocyanate is catalyzed by moisture in air; if the indices of the two polymers are matched, the coatings turn transparent after healing. Interference lithography offers a method of creating multifunctional self-healing coatings that readout when damage has occurred.

PMJ 2007 panel discussion overview: double exposure and double patterning for 32-nm half-pitch design node

NASA Astrophysics Data System (ADS)

Nagaoka, Yoshinori; Watanabe, Hidehiro

2007-10-01

As part of the technical program in Photomask Japan 2007, we held a panel discussion to discuss challenges and solutions for the double exposure and double patterning lithography technique for 32nm half-pitch design node. 4 panelists, Rik Jonckheere of IMEC, Belgium), Tsann-Binn Chiou of ASML Taiwan Ltd., Taiwan), Judy Huckabay of Cadence Design Systems Inc. (USA) and Yoshimitsu Okuda of Toppan Printing Co., Ltd., Japan) were invited to represent each key technical area. We also took a survey from the PMJ attendees prior to the panel discussion, to vote which key technical area they think the challenge exists for the 32nm half-pitch DE/DP lithography. The result of the survey was also presented during the panel discussion. One would intuitively think that by using a DE/DP technique you're relaxing the design rule by 2x, thus for 32nm node it's essentially the 65nm process- you're just repeating it 2 times. Well, not exactly, as identified by the panelists and the participants in the discussion. We recognized the difficulties in the LSI fabrication process steps, the lithography tool overlay, photomask CD and registration, and the issue of data splitting conflict. These difficulties are big challenge for both LSI and photomask manufactures; however, we have confirmed some solutions are already examined by the theoretical and experimental works of the people in research. Despite these difficulties, we are convinced that the immersion lithography with double exposure and double patterning techniques is one of the most promising candidates of the lithography for 32nm half pitch design node.

ILT optimization of EUV masks for sub-7nm lithography

NASA Astrophysics Data System (ADS)

Hooker, Kevin; Kuechler, Bernd; Kazarian, Aram; Xiao, Guangming; Lucas, Kevin

2017-06-01

The 5nm and 7nm technology nodes will continue recent scaling trends and will deliver significantly smaller minimum features, standard cell areas and SRAM cell areas vs. the 10nm node. There are tremendous economic pressures to shrink each subsequent technology, though in a cost-effective and performance enhancing manner. IC manufacturers are eagerly awaiting EUV so that they can more aggressively shrink their technology than they could by using complicated MPT. The current 0.33NA EUV tools and processes also have their patterning limitations. EUV scanner lenses, scanner sources, masks and resists are all relatively immature compared to the current lithography manufacturing baseline of 193i. For example, lens aberrations are currently several times larger (as a function of wavelength) in EUV scanners than for 193i scanners. Robustly patterning 16nm L/S fully random logic metal patterns and 40nm pitch random logic rectangular contacts with 0.33NA EUV are tough challenges that will benefit from advanced OPC/RET. For example, if an IC manufacturer can push single exposure device layer resolution 10% tighter using improved ILT to avoid using DPT, there will be a significant cost and process complexity benefit to doing so. ILT is well known to have considerable benefits in finding flexible 193i mask pattern solutions to improve process window, improve 2D CD control, improve resolution in low K1 lithography regime and help to delay the introduction of DPT. However, ILT has not previously been applied to EUV lithography. In this paper, we report on new developments which extend ILT method to EUV lithography and we characterize the benefits seen vs. traditional EUV OPC/RET methods.

Changes in the near edge X-ray absorption fine structure of hybrid organic-inorganic resists upon exposure.

PubMed

Fallica, Roberto; Watts, Benjamin; Roesner, Benedikt; Della Giustina, Gioia; Brigo, Laura; Brusatin, Giovanna; Ekinci, Yasin

2018-06-14

We report on the near edge X-ray absorption fine structure (NEXAFS) spectroscopy of hybrid organic-inorganic resists. These materials are nonchemically amplified systems based on Si, Zr, and Ti oxides, synthesized from organically modified precursors and transition metal alkoxides by a sol-gel route and designed for ultraviolet, extreme ultraviolet and electron beam lithography. The experiments were conducted using a scanning transmission X-ray microscope (STXM) which combines high spatial-resolution microscopy and NEXAFS spectroscopy. The absorption spectra were collected in the proximity of the carbon edge (~ 290 eV) before and after in situ exposure, enabling the measurement of a significant photo-induced degradation of the organic group (phenyl or methyl methacrylate, respectively), the degree of which depends on the configuration of the ligand. Photo-induced degradation was more efficient in the resist synthesized with pendant phenyl substituents than it was in the case of systems based on bridging phenyl groups. The degradation of the methyl methacrylate group was relatively efficient, with about half of the initial ligands dissociated upon exposure. Our data reveal that the such dissociation can produce different outcomes, depending on the structural configuration. While all the organic groups were expected to detach and desorb from the resist in their entirety, a sizeable amount of them remain and form undesired byproducts such as alkene chains. In the framework of the materials synthesis and engineering through specific building blocks, these results provide a deeper insight into the photochemistry of resists, in particular for extreme ultraviolet lithography. © 2018 IOP Publishing Ltd.

Nondestructive imaging of atomically thin nanostructures buried in silicon

PubMed Central

Gramse, Georg; Kölker, Alexander; Lim, Tingbin; Stock, Taylor J. Z.; Solanki, Hari; Schofield, Steven R.; Brinciotti, Enrico; Aeppli, Gabriel; Kienberger, Ferry; Curson, Neil J.

2017-01-01

It is now possible to create atomically thin regions of dopant atoms in silicon patterned with lateral dimensions ranging from the atomic scale (angstroms) to micrometers. These structures are building blocks of quantum devices for physics research and they are likely also to serve as key components of devices for next-generation classical and quantum information processing. Until now, the characteristics of buried dopant nanostructures could only be inferred from destructive techniques and/or the performance of the final electronic device; this severely limits engineering and manufacture of real-world devices based on atomic-scale lithography. Here, we use scanning microwave microscopy (SMM) to image and electronically characterize three-dimensional phosphorus nanostructures fabricated via scanning tunneling microscope–based lithography. The SMM measurements, which are completely nondestructive and sensitive to as few as 1900 to 4200 densely packed P atoms 4 to 15 nm below a silicon surface, yield electrical and geometric properties in agreement with those obtained from electrical transport and secondary ion mass spectroscopy for unpatterned phosphorus δ layers containing ~1013 P atoms. The imaging resolution was 37 ± 1 nm in lateral and 4 ± 1 nm in vertical directions, both values depending on SMM tip size and depth of dopant layers. In addition, finite element modeling indicates that resolution can be substantially improved using further optimized tips and microwave gradient detection. Our results on three-dimensional dopant structures reveal reduced carrier mobility for shallow dopant layers and suggest that SMM could aid the development of fabrication processes for surface code quantum computers. PMID:28782006

Electrolytic etching of fine stainless-steel pipes patterned by laser-scan lithography

NASA Astrophysics Data System (ADS)

Takahashi, Hiroshi; Sagara, Tomoya; Horiuchi, Toshiyuki

2017-07-01

Recently, it is required to develop a method for fabricating cylindrical micro-components in the field of measurement and medical engineering. Here, electrolytic etching of fine stainless-steel pipes patterned by laser-scan lithography was researched. The pipe diameter was 100 μm. At first, a pipe coated with 3-7 μm thick positive resist (tok, PMER P LA-900) was exposed to a violet laser beam with a wavelength of 408 nm (Neoark,TC20-4030-45). The laser beam was reshaped in a circle by placing a pinhole, and irradiated on the pipe by reducing the size in 1/20 using a reduction projection optics. Linearly arrayed 22 slit patterns with a width of 25 μm and a length of 175 μm were delineated in every 90-degree circumferential direction. That is, 88 slits in total were delineated at an exposure speed of 110 μm/s. In the axial direction, patterns were delineated at intervals of 90 μm. Following the pattern delineation, the pipe masked by the resist patterns was electrolytically etched. The pipe was used as an anode and an aluminum cylinder was set as a cathode around the pipe. As the electrolyte, aqueous solution of NaCl and NH4Cl was used. After etching the pipe, the resist was removed by ultrasonic cleaning in acetone. Although feasibility for fabricating multi-slit pipes was demonstrated, sizes of the etched slits were enlarged being caused by the undercut, and the shapes were partially deformed, and all the pipes were snapped at the chuck side.

Compensation of flare-induced CD changes EUVL

DOEpatents

Bjorkholm, John E [Pleasanton, CA; Stearns, Daniel G [Los Altos, CA; Gullikson, Eric M [Oakland, CA; Tichenor, Daniel A [Castro Valley, CA; Hector, Scott D [Oakland, CA

2004-11-09

A method for compensating for flare-induced critical dimensions (CD) changes in photolithography. Changes in the flare level results in undesirable CD changes. The method when used in extreme ultraviolet (EUV) lithography essentially eliminates the unwanted CD changes. The method is based on the recognition that the intrinsic level of flare for an EUV camera (the flare level for an isolated sub-resolution opaque dot in a bright field mask) is essentially constant over the image field. The method involves calculating the flare and its variation over the area of a patterned mask that will be imaged and then using mask biasing to largely eliminate the CD variations that the flare and its variations would otherwise cause. This method would be difficult to apply to optical or DUV lithography since the intrinsic flare for those lithographies is not constant over the image field.

Design survey of X-ray/XUV projection lithography systems

NASA Astrophysics Data System (ADS)

Shealy, David L.; Viswanathan, V. K.

1991-02-01

Several configurations of two- to four-multilayer mirror systems that have been proposed for use in soft-X-ray projection lithography are examined. The performance capabilities of spherical and aspherical two-mirror projection systems are compared, and a two-spherical-mirror four-reflection system that can resolve 0.1-micron features over a 10 x 10 mm field is described. It is emphasized that three-mirror systems show promise of high resolution in telescope applications, but have not been fully analyzed for projection lithography applications. It has been shown that a four-mirror aspheric system can be designed to meet the resolution requirements, but a trade-off must be made between reducing distortion below 10 microns over the field of view and increasing the modulation transfer function greater than 50 percent at spatial frequency of 5000 cycles/mm.

Conductive polymer nanowire gas sensor fabricated by nanoscale soft lithography

NASA Astrophysics Data System (ADS)

Tang, Ning; Jiang, Yang; Qu, Hemi; Duan, Xuexin

2017-12-01

Resistive devices composed of one-dimensional nanostructures are promising candidates for the next generation of gas sensors. However, the large-scale fabrication of nanowires is still challenging, which restricts the commercialization of such devices. Here, we report a highly efficient and facile approach to fabricating poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) nanowire chemiresistive gas sensors by nanoscale soft lithography. Well-defined sub-100 nm nanowires are fabricated on silicon substrate, which facilitates device integration. The nanowire chemiresistive gas sensor is demonstrated for NH3 and NO2 detection at room temperature and shows a limit of detection at ppb level, which is compatible with nanoscale PEDOT:PSS gas sensors fabricated with the conventional lithography technique. In comparison with PEDOT:PSS thin-film gas sensors, the nanowire gas sensor exhibits higher sensitivity and a much faster response to gas molecules.

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

Xu, Jia; Zhang, Ziang; Weng, Zhankun

This paper presents a new method for the generation of cross-scale laser interference patterns and the fabrication of moth-eye structures on silicon. In the method, moth-eye structures were produced on a surface of silicon wafer using direct six-beam laser interference lithography to improve the antireflection performance of the material surface. The periodic dot arrays of the moth-eye structures were formed due to the ablation of the irradiance distribution of interference patterns on the wafer surface. The shape, size, and distribution of the moth-eye structures can be adjusted by controlling the wavelength, incidence angles, and exposure doses in a direct six-beammore » laser interference lithography setup. The theoretical and experimental results have shown that direct six-beam laser interference lithography can provide a way to fabricate cross-scale moth-eye structures for antireflection applications.« less

Conductive polymer nanowire gas sensor fabricated by nanoscale soft lithography.

PubMed

Tang, Ning; Jiang, Yang; Qu, Hemi; Duan, Xuexin

2017-12-01

Resistive devices composed of one-dimensional nanostructures are promising candidates for the next generation of gas sensors. However, the large-scale fabrication of nanowires is still challenging, which restricts the commercialization of such devices. Here, we report a highly efficient and facile approach to fabricating poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) nanowire chemiresistive gas sensors by nanoscale soft lithography. Well-defined sub-100 nm nanowires are fabricated on silicon substrate, which facilitates device integration. The nanowire chemiresistive gas sensor is demonstrated for NH 3 and NO 2 detection at room temperature and shows a limit of detection at ppb level, which is compatible with nanoscale PEDOT:PSS gas sensors fabricated with the conventional lithography technique. In comparison with PEDOT:PSS thin-film gas sensors, the nanowire gas sensor exhibits higher sensitivity and a much faster response to gas molecules.

Micro and Nano Systems for Space Exploration

NASA Technical Reports Server (NTRS)

Manohara, Harish

2007-01-01

This slide presentation reviews the use of micro and nano systems in Space exploration. Included are: an explanation of the rationales behind nano and micro technologies for space exploration, a review of how the devices are fabricated, including details on lithography with more information on Electron Beam (E-Beam) lithography, and X-ray lithography, a review of micro gyroscopes and inchworm Microactuator as examples of the use of MicroElectoMechanical (MEMS) technology. Also included is information on Carbon Nanotubes, including a review of the CVD growth process. These micro-nano systems have given rise to the next generation of miniature X-ray Diffraction, X-ray Fluorescence instruments, mass spectrometers, and terahertz frequency vacuum tube oscillators and amplifiers, scanning electron microscopes and energy dispersive x-ray spectroscope. The nanotechnology has also given rise to coating technology, such as silicon nanotip anti-reflection coating.

A general lithography-free method of microscale/nanoscale fabrication and patterning on Si and Ge surfaces

PubMed Central

2012-01-01

Here, we introduce and give an overview of a general lithography-free method to fabricate silicide and germanide micro-/nanostructures on Si and Ge surfaces through metal-vapor-initiated endoepitaxial growth. Excellent controls on shape and orientation are achieved by adjusting the substrate orientation and growth parameters. Furthermore, micro-/nanoscale pits with controlled morphologies can also be successfully fabricated on Si and Ge surfaces by taking advantage of the sublimation of silicides/germanides. The aim of this brief report is to illustrate the concept of lithography-free synthesis and patterning on surfaces of elemental semiconductors, and the differences and the challenges associated with the Si and the Ge surfaces will be discussed. Our results suggest that this low-cost bottom-up approach is promising for applications in functional nanodevices. PMID:22315969

Lithography-free large-area metamaterials for stable thermophotovoltaic energy conversion

DOE PAGES

Coppens, Zachary J.; Kravchenko, Ivan I.; Valentine, Jason G.

2016-02-08

A large-area metamaterial thermal emitter is fabricated using facile, lithography-free techniques. The device is composed of conductive oxides, refractory ceramics, and noble metals and shows stable, selective emission after exposure to 1173 K for 22 h in oxidizing and inert atmospheres. Lastly, the results indicate that the metamaterial can be used to achieve high-performance thermophotovoltaic devices for applications such as portable power generation.

Three Dimensional Transient Analysis of Microstrip Circuits in Multilayered Anisotropic Media

DTIC Science & Technology

1991-11-14

dimensions, resonance is possible within the low gigahertz frequency range. Because the effects of diffraction during proximity-print x-ray lithography ...facilitate lead passage. The simulation results, comparing radi- paksgo and sourcl ation from a gasketed and ungasketed heatsink with an dMD TPI as... lithography are of critical importance, a number of previous researchers have attempted to calculate the diffraction patterns and minimum achievable

Novel Processes for Modular Integration of Silicon-Germanium MEMS with CMOS Electronics

DTIC Science & Technology

2007-02-28

process limits the compatibility with further lithography steps. Using silicon as the MEMS structural material, most of the integration processes...structures are defined by lithography and deep reactive ion etching. A layer of gasket oxide is deposited as the sacrificial material between the...When the Bragg condition for constructive interference is obtained, a diffraction peak is produced and the relative peak height is proportional to

All-optical lithography process for contacting nanometer precision donor devices

NASA Astrophysics Data System (ADS)

Ward, D. R.; Marshall, M. T.; Campbell, D. M.; Lu, T. M.; Koepke, J. C.; Scrymgeour, D. A.; Bussmann, E.; Misra, S.

2017-11-01

We describe an all-optical lithography process that can make electrical contact to nanometer-precision donor devices fabricated in silicon using scanning tunneling microscopy (STM). This is accomplished by implementing a cleaning procedure in the STM that allows the integration of metal alignment marks and ion-implanted contacts at the wafer level. Low-temperature transport measurements of a patterned device establish the viability of the process.

All-optical lithography process for contacting nanometer precision donor devices

DOE PAGES

Ward, Daniel Robert; Marshall, Michael Thomas; Campbell, DeAnna Marie; ...

2017-11-06

In this article, we describe an all-optical lithography process that can make electrical contact to nanometer-precision donor devices fabricated in silicon using scanning tunneling microscopy (STM). This is accomplished by implementing a cleaning procedure in the STM that allows the integration of metal alignment marks and ion-implanted contacts at the wafer level. Low-temperature transport measurements of a patterned device establish the viability of the process.

Etched-multilayer phase shifting masks for EUV lithography

DOEpatents

Chapman, Henry N.; Taylor, John S.

2005-04-05

A method is disclosed for the implementation of phase shifting masks for EUV lithography. The method involves directly etching material away from the multilayer coating of the mask, to cause a refractive phase shift in the mask. By etching into the multilayer (for example, by reactive ion etching), rather than depositing extra material on the top of the multilayer, there will be minimal absorption loss associated with the phase shift.

Large area fabrication of plasmonic nanoparticle grating structure by conventional scanning electron microscope

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

Sudheer,, E-mail: sudheer@rrcat.gov.in; Tiwari, P.; Rai, V. N.

Plasmonic nanoparticle grating (PNG) structure of different periods has been fabricated by electron beam lithography using silver halide based transmission electron microscope film as a substrate. Conventional scanning electron microscope is used as a fabrication tool for electron beam lithography. Optical microscope and energy dispersive spectroscopy (EDS) have been used for its morphological and elemental characterization. Optical characterization is performed by UV-Vis absorption spectroscopic technique.

All-optical lithography process for contacting nanometer precision donor devices

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

Ward, Daniel Robert; Marshall, Michael Thomas; Campbell, DeAnna Marie

In this article, we describe an all-optical lithography process that can make electrical contact to nanometer-precision donor devices fabricated in silicon using scanning tunneling microscopy (STM). This is accomplished by implementing a cleaning procedure in the STM that allows the integration of metal alignment marks and ion-implanted contacts at the wafer level. Low-temperature transport measurements of a patterned device establish the viability of the process.

Defect printability for high-exposure dose advanced packaging applications

NASA Astrophysics Data System (ADS)

Mikles, Max; Flack, Warren; Nguyen, Ha-Ai; Schurz, Dan

2003-12-01

Pellicles are used in semiconductor lithography to minimize printable defects and reduce reticle cleaning frequency. However, there are a growing number of microlithography applications, such as advanced packaging and nanotechnology, where it is not clear that pellicles always offer a significant benefit. These applications have relatively large critical dimensions and require ultra thick photoresists with extremely high exposure doses. Given that the lithography is performed in Class 100 cleanroom conditions, it is possible that the risk of defects from contamination is sufficiently low that pellicles would not be required on certain process layer reticles. The elimination of the pellicle requirement would provide a cost reduction by saving the original pellicle cost and eliminating future pellicle replacement and repair costs. This study examines the imaging potential of defects with reticle patterns and processes typical for gold-bump and solder-bump advanced packaging lithography. The test reticle consists of 30 to 90 μm octagonal contact patterns representative of advanced packaging reticles. Programmed defects are added that represent the range of particle sizes (3 to 30 μm) normally protected by the pellicle and that are typical of advanced packaging lithography cleanrooms. The reticle is exposed using an Ultratech Saturn Spectrum 300e2 1X stepper on wafers coated with a variety of ultra thick (30 to 100 μm) positive and negative-acting photoresists commonly used in advanced packaging. The experimental results show that in many cases smaller particles continue to be yield issues for the feature size and density typical of advanced packaging processes. For the two negative photoresists studied it appears that a pellicle is not required for protection from defects smaller than 10 to 15 μm depending on the photoresist thickness. Thus the decision on pellicle usage for these materials would need to be made based on the device fabrication process and the cleanliness of a fabrication facility. For the two positive photoresists studied it appears that a pellicle is required to protect from defects down to 3 μm defects depending on the photoresist thickness. This suggests that a pellicle should always be used for these materials. Since a typical fabrication facility would use both positive and negative photoresists it may be advantageous to use pellicles on all reticles simply to avoid confusion. The cost savings of not using a pellicle could easily be outweighed by the yield benefits of using one.

Microfluidic-based photocatalytic microreactor for environmental application: a review of fabrication substrates and techniques, and operating parameters.

PubMed

Das, Susmita; Srivastava, Vimal Chandra

2016-06-08

Photochemical technology with microfluidics is emerging as a new platform in environmental science. Microfluidic technology has various advantages, like better mixing and a shorter diffusion distance for the reactants and products; and uniform distribution of light on the photocatalyst. Depending on the material type and related applications, several fabrication techniques have been adopted by various researchers. Microreactors have been prepared by various techniques, such as lithography, etching, mechanical microcutting technology, etc. Lithography can be classified into photolithography, soft lithography and X-ray lithography techniques whereas the etching process is divided into wet etching (chemical etching) and dry etching (plasma etching) techniques. Several substrates, like polymers, such as polydimethyl-siloxane (PDMS), polymethyle-methacrylate (PMMA), hydrogel, etc.; metals, such as stainless steel, titanium foil, etc.; glass, such as silica capillary, glass slide, etc.; and ceramics have been used for microchannel fabrication. During degradation in a microreactor, the degradation efficiency is affected by few important parameters such as flow rate, initial concentration of the target compound, microreactor dimensions, light intensity, photocatalyst structure and catalyst support. The present paper discusses and critically reviews fabrication techniques and substrates used for microchannel fabrication and critical operating parameters for organics, especially dye degradation in the microreactor. The kinetics of degradation has also been discussed.

Proximity Effect Correction by Pattern Modified Stencil Mask in Large-Field Projection Electron-Beam Lithography

NASA Astrophysics Data System (ADS)

Kobinata, Hideo; Yamashita, Hiroshi; Nomura, Eiichi; Nakajima, Ken; Kuroki, Yukinori

1998-12-01

A new method for proximity effect correction, suitable for large-field electron-beam (EB) projection lithography with high accelerating voltage, such as SCALPEL and PREVAIL in the case where a stencil mask is used, is discussed. In this lithography, a large-field is exposed by the same dose, and thus, the dose modification method, which is used in the variable-shaped beam and the cell projection methods, cannot be used in this case. In this study, we report on development of a new proximity effect correction method which uses a pattern modified stencil mask suitable for high accelerating voltage and large-field EB projection lithography. In order to obtain the mask bias value, we have investigated linewidth reduction, due to the proximity effect, in the peripheral memory cell area, and found that it could be expressed by a simple function and all the correction parameters were easily determined from only the mask pattern data. The proximity effect for the peripheral array pattern could also be corrected by considering the pattern density. Calculated linewidth deviation was 3% or less for a 0.07-µm-L/S memory cell pattern and 5% or less for a 0.14-µm-line and 0.42-µm-space peripheral array pattern, simultaneously.

Automated scanning probe lithography with n-alkanethiol self assembled monolayers on Au(111): Application for teaching undergraduate laboratories

PubMed Central

Brown, Treva T.; LeJeune, Zorabel M.; Liu, Kai; Hardin, Sean; Li, Jie-Ren; Rupnik, Kresimir; Garno, Jayne C.

2010-01-01

Controllers for scanning probe instruments can be programmed for automated lithography to generate desired surface arrangements of nanopatterns of organic thin films, such as n-alkanethiol self-assembled monolayers (SAMs). In this report, atomic force microscopy (AFM) methods of lithography known as nanoshaving and nanografting are used to write nanopatterns within organic thin films. Commercial instruments provide software to control the length, direction, speed, and applied force of the scanning motion of the tip. For nanoshaving, higher forces are applied to an AFM tip to selectively remove regions of the matrix monolayer, exposing bare areas of the gold substrate. Nanografting is accomplished by force-induced displacement of molecules of a matrix SAM, followed immediately by the surface self-assembly of n-alkanethiol molecules from solution. Advancements in AFM automation enable rapid protocols for nanolithography, which can be accomplished within the tight time restraints of undergraduate laboratories. Example experiments with scanning probe lithography (SPL) will be described in this report that were accomplished by undergraduate students during laboratory course activities and research internships in the chemistry department of Louisiana State University. Students were introduced to principles of surface analysis and gained “hands-on” experience with nanoscale chemistry. PMID:21483651

Implementation and benefits of advanced process control for lithography CD and overlay

NASA Astrophysics Data System (ADS)

Zavyalova, Lena; Fu, Chong-Cheng; Seligman, Gary S.; Tapp, Perry A.; Pol, Victor

2003-05-01

Due to the rapidly reduced imaging process windows and increasingly stingent device overlay requirements, sub-130 nm lithography processes are more severely impacted than ever by systamic fault. Limits on critical dimensions (CD) and overlay capability further challenge the operational effectiveness of a mix-and-match environment using multiple lithography tools, as such mode additionally consumes the available error budgets. Therefore, a focus on advanced process control (APC) methodologies is key to gaining control in the lithographic modules for critical device levels, which in turn translates to accelerated yield learning, achieving time-to-market lead, and ultimately a higher return on investment. This paper describes the implementation and unique challenges of a closed-loop CD and overlay control solution in high voume manufacturing of leading edge devices. A particular emphasis has been placed on developing a flexible APC application capable of managing a wide range of control aspects such as process and tool drifts, single and multiple lot excursions, referential overlay control, 'special lot' handling, advanced model hierarchy, and automatic model seeding. Specific integration cases, including the multiple-reticle complementary phase shift lithography process, are discussed. A continuous improvement in the overlay and CD Cpk performance as well as the rework rate has been observed through the implementation of this system, and the results are studied.

Automated imprint mask cleaning for step-and-flash imprint lithography

NASA Astrophysics Data System (ADS)

Singh, Sherjang; Chen, Ssuwei; Selinidis, Kosta; Fletcher, Brian; McMackin, Ian; Thompson, Ecron; Resnick, Douglas J.; Dress, Peter; Dietze, Uwe

2009-03-01

Step-and-Flash Imprint Lithography (S-FIL) is a promising lithography strategy for semiconductor manufacturing at device nodes below 32nm. The S-FIL 1:1 pattern transfer technology utilizes a field-by-field ink jet dispense of a low viscosity liquid resist to fill the relief pattern of the device layer etched into the glass mask. Compared to other sub 40nm CD lithography methods, the resulting high resolution, high throughput through clustering, 3D patterning capability, low process complexity, and low cost of ownership (CoO) of S-FIL makes it a widely accepted technology for patterned media as well as a promising mainstream option for future CMOS applications. Preservation of mask cleanliness is essential to avoid risk of repeated printing of defects. The development of mask cleaning processes capable of removing particles adhered to the mask surface without damaging the mask is critical to meet high volume manufacturing requirements. In this paper we have presented various methods of residual (cross-linked) resist removal and final imprint mask cleaning demonstrated on the HamaTech MaskTrack automated mask cleaning system. Conventional and non-conventional (acid free) methods of particle removal have been compared and the effect of mask cleaning on pattern damage and CD integrity is also studied.

Hylemetry versus Biometry: a new method to certificate the lithography authenticity

NASA Astrophysics Data System (ADS)

Schirripa Spagnolo, Giuseppe; Cozzella, Lorenzo; Simonetti, Carla

2011-06-01

When we buy an artwork object a certificate of authenticity contain specific details about the artwork. Unfortunately, these certificates are often exchanged between similar artworks: the same document is supplied by the seller to certificate the originality. In this way the buyer will have a copy of an original certificate to attest that the "not original artwork" is an original one. A solution for this problem would be to insert a system that links together the certificate and a specific artwork. To do this it is necessary, for a single artwork, to find unique, unrepeatable, and unchangeable characteristics. In this paper we propose a new lithography certification based on the color spots distribution, which compose the lithography itself. Due to the high resolution acquisition media available today, it is possible using analysis method typical of speckle metrology. In particular, in verification phase it is only necessary acquiring the same portion of lithography, extracting the verification information, using the private key to obtain the same information from the certificate and confronting the two information using a comparison threshold. Due to the possible rotation and translation it is applied image correlation solutions, used in speckle metrology, to determine translation and rotation error and correct allow to verifying extracted and acquired images in the best situation, for granting correct originality verification.

30 GHz monolithic balanced mixers using an ion-implanted FET-compatible 3-inch GaAs wafer process technology

NASA Technical Reports Server (NTRS)

Bauhahn, P.; Contolatis, A.; Sokolov, V.; Chao, C.

1986-01-01

An all ion-implanted Schottky barrier mixer diode which has a cutoff frequency greater than 1000 GHz has been developed. This new device is planar and FET-compatible and employs a projection lithography 3-inch wafer process. A Ka-band monolithic balanced mixer based on this device has been designed, fabricated and tested. A conversion loss of 8 dB has been measured with a LO drive of 10 dBm at 30 GHz.

Micro/nano electro mechanical systems for practical applications

NASA Astrophysics Data System (ADS)

Esashi, Masayoshi

2009-09-01

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

A micro-scale plasma spectrometer for space and plasma edge applications (invited)

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

Scime, E. E., E-mail: escime@wvu.edu; Keesee, A. M.; Elliott, D.

2016-11-15

A plasma spectrometer design based on advances in lithography and microchip stacking technologies is described. A series of curved plate energy analyzers, with an integrated collimator, is etched into a silicon wafer. Tests of spectrometer elements, the energy analyzer and collimator, were performed with a 5 keV electron beam. The measured collimator transmission and energy selectivity were in good agreement with design targets. A single wafer element could be used as a plasma processing or fusion first wall diagnostic.

Characterization of photochromic computer-generated holograms for optical testing

NASA Astrophysics Data System (ADS)

Pariani, Giorgio; Bertarelli, Chiara; Bianco, Andrea; Schaal, Frederik; Pruss, Christof

2012-09-01

We investigate the possibility to produce photochromic CGHs with maskless lithography methods. For this purpose, optical properties and requirements of photochromic materials will be shown. A diarylethene-based polyurethane is developed and characterized. The resolution limit and the in uence of the writing parameters on the produced patterns, namely speed rate and light power, have been determined. After the optimization of the writing process, gratings and Fresnel Zone Plates are produced on the photochromic layer and diraction eciencies are measured. Improvements and perspectives will be discussed.

Align-and-shine photolithography

NASA Astrophysics Data System (ADS)

Petrusis, Audrius; Rector, Jan H.; Smith, Kristen; de Man, Sven; Iannuzzi, Davide

2009-10-01

At the beginning of 2009, our group has introduced a new technique that allows fabrication of photolithographic patterns on the cleaved end of an optical fibre: the align-and-shine photolithography technique (see A. Petrušis et al., "The align-and-shine technique for series production of photolithography patterns on optical fibres", J. Micromech. Microeng. 19, 047001, 2009). Align-and-shine photolithography combines standard optical lithography with imagebased active fibre alignment processes. The technique adapts well to series production, opening the way to batch fabrication of fibre-top devices (D. Iannuzzi et al., "Monolithic fibre-top cantilever for critical environments and standard applications", Appl. Phys. Lett. 88, 053501, 2006) and all other devices that rely on suitable machining of engineered parts on the tip of a fibre. In this paper we review our results and briefly discuss its potential applications.

Synthesis of Large-grain, Single-crystalline Monolayer and AB-stacking Bilayer Graphene

NASA Astrophysics Data System (ADS)

Zhang, Luyao; Lin, Yung-Chen; Zhang, Yi; Chang, Han-Wen; Yeh, Wen-Cheng; Zhou, Chongwu; USC Nanotechnology Research Laboratory Team

2013-03-01

We report the growth of large-grain, single-crystalline monolayer and AB-stacking bilayer graphene by the combination of ambient pressure chemical vapor deposition and low pressure chemical vapor deposition. The shape of the monolayer graphene was modified to be either hexagons or flowers under different growth conditions. The size of the bilayer graphene region was enlarged under ambient pressure growth conditions with low methane concentration. Raman spectra and selected area electron diffraction of individual graphene grain indicated that the each graphene grain is single-crystalline. With electron beam lithography patterned PMMA seeds, graphene nucleation can be controlled and graphene monolayer and bilayer arrays were synthesized on copper foil. Electron backscatter diffraction study revealed that the graphene morphology had little correlation with the crystalline orientation of underlying copper substrate. Mork Family Department of Chemical Engineering and Materials Science

Nanostructured silicon membranes for control of molecular transport.

PubMed

Srijanto, Bernadeta R; Retterer, Scott T; Fowlkes, Jason D; Doktycz, Mitchel J

2010-11-01

A membrane that allows selective transport of molecular species requires precise engineering on the nanoscale. Membrane permeability can be tuned by controlling the physical structure and surface chemistry of the pores. Here, a combination of electron beam and optical lithography, along with cryogenic deep reactive ion etching, has been used to fabricate silicon membranes that are physically robust, have uniform pore sizes, and are directly integrated into a microfluidic network. Additional reductions in pore size were achieved using plasma enhanced chemical vapor deposition and atomic layer deposition of silicon dioxide to coat membrane surfaces. Cross sectioning of the membranes using focused ion beam milling was used to determine the physical shape of the membrane pores before and after coating. Functional characterization of the membranes was performed by using quantitative fluorescence microscopy to document the transport of molecular species across the membrane.

Frequency tunable near-infrared metamaterials based on VO2 phase transition.

PubMed

Dicken, Matthew J; Aydin, Koray; Pryce, Imogen M; Sweatlock, Luke A; Boyd, Elizabeth M; Walavalkar, Sameer; Ma, James; Atwater, Harry A

2009-09-28

Engineering metamaterials with tunable resonances from mid-infrared to near-infrared wavelengths could have far-reaching consequences for chip based optical devices, active filters, modulators, and sensors. Utilizing the metal-insulator phase transition in vanadium oxide (VO(2)), we demonstrate frequency-tunable metamaterials in the near-IR range, from 1.5 - 5 microns. Arrays of Ag split ring resonators (SRRs) are patterned with e-beam lithography onto planar VO(2) and etched via reactive ion etching to yield Ag/VO(2) hybrid SRRs. FTIR reflection data and FDTD simulation results show the resonant peak position red shifts upon heating above the phase transition temperature. We also show that, by including coupling elements in the design of these hybrid Ag/VO(2) bi-layer structures, we can achieve resonant peak position tuning of up to 110 nm.

Spun-wrapped aligned nanofiber (SWAN) lithography for fabrication of micro/nano-structures on 3D objects

NASA Astrophysics Data System (ADS)

Ye, Zhou; Nain, Amrinder S.; Behkam, Bahareh

2016-06-01

Fabrication of micro/nano-structures on irregularly shaped substrates and three-dimensional (3D) objects is of significant interest in diverse technological fields. However, it remains a formidable challenge thwarted by limited adaptability of the state-of-the-art nanolithography techniques for nanofabrication on non-planar surfaces. In this work, we introduce Spun-Wrapped Aligned Nanofiber (SWAN) lithography, a versatile, scalable, and cost-effective technique for fabrication of multiscale (nano to microscale) structures on 3D objects without restriction on substrate material and geometry. SWAN lithography combines precise deposition of polymeric nanofiber masks, in aligned single or multilayer configurations, with well-controlled solvent vapor treatment and etching processes to enable high throughput (>10-7 m2 s-1) and large-area fabrication of sub-50 nm to several micron features with high pattern fidelity. Using this technique, we demonstrate whole-surface nanopatterning of bulk and thin film surfaces of cubes, cylinders, and hyperbola-shaped objects that would be difficult, if not impossible to achieve with existing methods. We demonstrate that the fabricated feature size (b) scales with the fiber mask diameter (D) as b1.5 ~ D. This scaling law is in excellent agreement with theoretical predictions using the Johnson, Kendall, and Roberts (JKR) contact theory, thus providing a rational design framework for fabrication of systems and devices that require precisely designed multiscale features.Fabrication of micro/nano-structures on irregularly shaped substrates and three-dimensional (3D) objects is of significant interest in diverse technological fields. However, it remains a formidable challenge thwarted by limited adaptability of the state-of-the-art nanolithography techniques for nanofabrication on non-planar surfaces. In this work, we introduce Spun-Wrapped Aligned Nanofiber (SWAN) lithography, a versatile, scalable, and cost-effective technique for fabrication of multiscale (nano to microscale) structures on 3D objects without restriction on substrate material and geometry. SWAN lithography combines precise deposition of polymeric nanofiber masks, in aligned single or multilayer configurations, with well-controlled solvent vapor treatment and etching processes to enable high throughput (>10-7 m2 s-1) and large-area fabrication of sub-50 nm to several micron features with high pattern fidelity. Using this technique, we demonstrate whole-surface nanopatterning of bulk and thin film surfaces of cubes, cylinders, and hyperbola-shaped objects that would be difficult, if not impossible to achieve with existing methods. We demonstrate that the fabricated feature size (b) scales with the fiber mask diameter (D) as b1.5 ~ D. This scaling law is in excellent agreement with theoretical predictions using the Johnson, Kendall, and Roberts (JKR) contact theory, thus providing a rational design framework for fabrication of systems and devices that require precisely designed multiscale features. Electronic supplementary information (ESI) available: SWAN lithography on silicon; comparison of SWAN lithography and state-of-the-art nanopatterning methods; replica molding using SWAN lithography fabricated template; PDMS nanofluidic device, gold nanopattern characterization. See DOI: 10.1039/c6nr03323g

In-Plane Electrical Connectivity and Near-Field Concentration of Isolated Graphene Resonators Realized by Ion Beams.

PubMed

Luo, Weiwei; Cai, Wei; Xiang, Yinxiao; Wu, Wei; Shi, Bin; Jiang, Xiaojie; Zhang, Ni; Ren, Mengxin; Zhang, Xinzheng; Xu, Jingjun

2017-08-01

Graphene plasmons provide great opportunities in light-matter interactions benefiting from the extreme confinement and electrical tunability. Structured graphene cavities possess enhanced confinements in 3D and steerable plasmon resonances, potential in applications for sensing and emission control at the nanoscale. Besides graphene boundaries obtained by mask lithography, graphene defects engineered by ion beams have shown efficient plasmon reflections. In this paper, near-field responses of structured graphene achieved by ion beam direct-writing are investigated. Graphene nanoresonators are fabricated easily and precisely with a spatial resolution better than 30 nm. Breathing modes are observed in graphene disks. The amorphous carbons around weaken the response of edge modes in the resonators, but meanwhile render the isolated resonators in-plane electrical connections, where near-fields are proved gate-tunable. The realization of gate-tunable near-fields of graphene 2D resonators opens up tunable near-field couplings with matters. Moreover, graphene nonconcentric rings with engineered near-field confinement distributions are demonstrated, where the quadrupole plasmon modes are excited. Near-field mappings reveal concentrations at the scale of 3.8×10-4λ02 within certain zones which can be engineered. The realization of electrically tunable graphene nanoresonators by ion beam direct-writing is promising for active manipulation of emission and sensing at the nanoscale. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chromaticity calculations and code comparisons for x-ray lithography source XLS and SXLS rings

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

Parsa, Z.

1988-06-16

This note presents the chromaticity calculations and code comparison results for the (x-ray lithography source) XLS (Chasman Green, XUV Cosy lattice) and (2 magnet 4T) SXLS lattices, with the standard beam optic codes, including programs SYNCH88.5, MAD6, PATRICIA88.4, PATPET88.2, DIMAD, BETA, and MARYLIE. This analysis is a part of our ongoing accelerator physics code studies. 4 figs., 10 tabs.

Cooperative simulation of lithography and topography for three-dimensional high-aspect-ratio etching

NASA Astrophysics Data System (ADS)

Ichikawa, Takashi; Yagisawa, Takashi; Furukawa, Shinichi; Taguchi, Takafumi; Nojima, Shigeki; Murakami, Sadatoshi; Tamaoki, Naoki

2018-06-01

A topography simulation of high-aspect-ratio etching considering transports of ions and neutrals is performed, and the mechanism of reactive ion etching (RIE) residues in three-dimensional corner patterns is revealed. Limited ion flux and CF2 diffusion from the wide space of the corner is found to have an effect on the RIE residues. Cooperative simulation of lithography and topography is used to solve the RIE residue problem.

Electrically conducting nanopatterns formed by chemical e-beam lithography via gold nanoparticle seeds.

PubMed

Schaal, Patrick A; Besmehn, Astrid; Maynicke, Eva; Noyong, Michael; Beschoten, Bernd; Simon, Ulrich

2012-02-07

We report the formation of thiol nanopatterns on SAM covered silicon wafers by converting sulfonic acid head groups via e-beam lithography. These thiol groups act as binding sites for gold nanoparticles, which can be enhanced to form electrically conducting nanostructures. This approach serves as a proof-of-concept for the combination of top-down and bottom-up processes for the generation of electrical devices on silicon.

Mask manufacturing of advanced technology designs using multi-beam lithography (Part 1)

NASA Astrophysics Data System (ADS)

Green, Michael; Ham, Young; Dillon, Brian; Kasprowicz, Bryan; Hur, Ik Boum; Park, Joong Hee; Choi, Yohan; McMurran, Jeff; Kamberian, Henry; Chalom, Daniel; Klikovits, Jan; Jurkovic, Michal; Hudek, Peter

2016-10-01

As optical lithography is extended into 10nm and below nodes, advanced designs are becoming a key challenge for mask manufacturers. Techniques including advanced Optical Proximity Correction (OPC) and Inverse Lithography Technology (ILT) result in structures that pose a range of issues across the mask manufacturing process. Among the new challenges are continued shrinking Sub-Resolution Assist Features (SRAFs), curvilinear SRAFs, and other complex mask geometries that are counter-intuitive relative to the desired wafer pattern. Considerable capability improvements over current mask making methods are necessary to meet the new requirements particularly regarding minimum feature resolution and pattern fidelity. Advanced processes using the IMS Multi-beam Mask Writer (MBMW) are feasible solutions to these coming challenges. In this paper, we study one such process, characterizing mask manufacturing capability of 10nm and below structures with particular focus on minimum resolution and pattern fidelity.

Mask manufacturing of advanced technology designs using multi-beam lithography (part 2)

NASA Astrophysics Data System (ADS)

Green, Michael; Ham, Young; Dillon, Brian; Kasprowicz, Bryan; Hur, Ik Boum; Park, Joong Hee; Choi, Yohan; McMurran, Jeff; Kamberian, Henry; Chalom, Daniel; Klikovits, Jan; Jurkovic, Michal; Hudek, Peter

2016-09-01

As optical lithography is extended into 10nm and below nodes, advanced designs are becoming a key challenge for mask manufacturers. Techniques including advanced optical proximity correction (OPC) and Inverse Lithography Technology (ILT) result in structures that pose a range of issues across the mask manufacturing process. Among the new challenges are continued shrinking sub-resolution assist features (SRAFs), curvilinear SRAFs, and other complex mask geometries that are counter-intuitive relative to the desired wafer pattern. Considerable capability improvements over current mask making methods are necessary to meet the new requirements particularly regarding minimum feature resolution and pattern fidelity. Advanced processes using the IMS Multi-beam Mask Writer (MBMW) are feasible solutions to these coming challenges. In this paper, Part 2 of our study, we further characterize an MBMW process for 10nm and below logic node mask manufacturing including advanced pattern analysis and write time demonstration.

Mask technology for EUV lithography

NASA Astrophysics Data System (ADS)

Bujak, M.; Burkhart, Scott C.; Cerjan, Charles J.; Kearney, Patrick A.; Moore, Craig E.; Prisbrey, Shon T.; Sweeney, Donald W.; Tong, William M.; Vernon, Stephen P.; Walton, Christopher C.; Warrick, Abbie L.; Weber, Frank J.; Wedowski, Marco; Wilhelmsen, Karl C.; Bokor, Jeffrey; Jeong, Sungho; Cardinale, Gregory F.; Ray-Chaudhuri, Avijit K.; Stivers, Alan R.; Tejnil, Edita; Yan, Pei-yang; Hector, Scott D.; Nguyen, Khanh B.

1999-04-01

Extreme UV Lithography (EUVL) is one of the leading candidates for the next generation lithography, which will decrease critical feature size to below 100 nm within 5 years. EUVL uses 10-14 nm light as envisioned by the EUV Limited Liability Company, a consortium formed by Intel and supported by Motorola and AMD to perform R and D work at three national laboratories. Much work has already taken place, with the first prototypical cameras operational at 13.4 nm using low energy laser plasma EUV light sources to investigate issues including the source, camera, electro- mechanical and system issues, photoresists, and of course the masks. EUV lithograph masks are fundamentally different than conventional photolithographic masks as they are reflective instead of transmissive. EUV light at 13.4 nm is rapidly absorbed by most materials, thus all light transmission within the EUVL system from source to silicon wafer, including EUV reflected from the mask, is performed by multilayer mirrors in vacuum.

GaN-based light emitting diodes using p-type trench structure for improving internal quantum efficiency

NASA Astrophysics Data System (ADS)

Kim, Garam; Sun, Min-Chul; Kim, Jang Hyun; Park, Euyhwan; Park, Byung-Gook

2017-01-01

In order to improve the internal quantum efficiency of GaN-based LEDs, a LED structure featuring a p-type trench in the multi-quantum well (MQW) is proposed. This structure has effects on spreading holes into the MQW and reducing the quantum-confined stark effect (QCSE). In addition, two simple fabrication methods using electron-beam (e-beam) lithography or selective wet etching for manufacturing the p-type structure are also proposed. From the measurement results of the manufactured GaN-based LEDs, it is confirmed that the proposed structure using e-beam lithography or selective wet etching shows improved light output power compared to the conventional structure because of more uniform hole distribution. It is also confirmed that the proposed structure formed by e-beam lithography has a significant effect on strain relaxation and reduction in the QCSE from the electro-luminescence measurement.

Fabrication of hexagonal star-shaped and ring-shaped patterns arrays by Mie resonance sphere-lens-lithography

NASA Astrophysics Data System (ADS)

Liu, Xianchao; Wang, Jun; Li, Ling; Gou, Jun; Zheng, Jie; Huang, Zehua; Pan, Rui

2018-05-01

Mie resonance sphere-lens-lithography has proved to be a good candidate for fabrication of large-area tunable surface nanopattern arrays. Different patterns on photoresist surface are obtained theoretically by adjusting optical coupling among neighboring spheres with different gap sizes. The effect of light reflection from the substrate on the pattern produced on the photoresist with a thin thickness is also discussed. Sub-micron hexagonal star-shaped and ring-shaped patterns arrays are achieved with close-packed spheres arrays and spheres arrays with big gaps, respectively. Changing of star-shaped vertices is induced by different polarization of illumination. Experimental results agree well with the simulation. By using smaller resonance spheres, sub-400 nm star-shaped and ring-shaped patterns can be realized. These tunable patterns are different from results of previous reports and have enriched pattern morphology fabricated by sphere-lens-lithography, which can find application in biosensor and optic devices.

Micro-optical foundry: 3D lithography by freezing liquid instabilities at nanoscale

NASA Astrophysics Data System (ADS)

Grilli, S.; Coppola, S.; Vespini, V.; Merola, F.; Finizio, A.; Ferraro, P.

2012-06-01

The pyroelectric functionality of a Lithium Niobate (LN) substrate is used for non-contact manipulation of polymeric material. In this work we introduced a novel approach for fabricating a wide variety of soft solid-like microstructures, thus leading to a new concept in 3D lithography. A relatively easy to accomplish technique has been demonstrated for curing different transient stages of polymer fluids by rapid cross-linking of PDMS. The method is twofold innovative thanks to the electrode-less configuration and to the rapid formation of a wide variety of 3D solid-like structures by exploiting polymer instabilities. This new and unique technique is named "pyro-electrohydrodynamic (PEHD) lithography", meaning the generation of structures by using forces produced by electric fields generated by the pyroelectric effect. The fabrication of polymer wires, needles, pillars, cones, or microspheres is reported, and practical proofs of their use in photonics are presented.

Photomask quality evaluation using lithography simulation and precision SEM image contour data

NASA Astrophysics Data System (ADS)

Murakawa, Tsutomu; Fukuda, Naoki; Shida, Soichi; Iwai, Toshimichi; Matsumoto, Jun; Nakamura, Takayuki; Hagiwara, Kazuyuki; Matsushita, Shohei; Hara, Daisuke; Adamov, Anthony

2012-11-01

To evaluate photomask quality, the current method uses spatial imaging by optical inspection tools. This technique at 1Xnm node has a resolution limit because small defects will be difficult to extract. To simulate the mask error-enhancement factor (MEEF) influence for aggressive OPC in 1Xnm node, wide FOV contour data and tone information are derived from high precision SEM images. For this purpose we have developed a new contour data extraction algorithm with sub-nanometer accuracy resulting in a wide Field of View (FOV) SEM image: (for example, more than 10um x 10um square). We evaluated MEEF influence of high-end photomask pattern using the wide FOV contour data of "E3630 MVM-SEMTM" and lithography simulator "TrueMaskTM DS" of D2S, Inc. As a result, we can detect the "invisible defect" as the MEEF influence using the wide FOV contour data and lithography simulator.

Modulated grayscale UV pattern for uniform photopolymerization based on a digital micromirror device system

NASA Astrophysics Data System (ADS)

Yoon, Jinsik; Kim, Kibeom; Park, Wook

2017-07-01

We present an essential method for generating microparticles uniformly in a single ultraviolet (UV) light exposure area for optofluidic maskless lithography. In the optofluidic maskless lithography process, the productivity of monodisperse microparticles depends on the size of the UV exposure area. An effective fabrication area is determined by the size of the UV intensity profile map, satisfying the required uniformity of UV intensity. To increase the productivity of monodisperse microparticles in optofluidic maskless lithography, we expanded the effective UV exposure area by modulating the intensity of the desired UV light pattern based on the premeasured UV intensity profile map. We verified the improvement of the uniformity of the microparticles generated by the proposed modulation technique, providing histogram analyses of the conjugated fluorescent intensities and the sizes of the microparticles. Additionally, we demonstrated the generation of DNA uniformly encapsulated in microparticles.

Latest results on solarization of optical glasses with pulsed laser radiation

NASA Astrophysics Data System (ADS)

Jedamzik, Ralf; Petzold, Uwe

2017-02-01

Femtosecond lasers are more and more used for material processing and lithography. Femtosecond laser help to generate three dimensional structures in photoresists without using masks in micro lithography. This technology is of growing importance for the field of backend lithography or advanced packaging. Optical glasses used for beam shaping and inspection tools need to withstand high laser pulse energies. Femtosecond laser radiation in the near UV wavelength range generates solarization effects in optical glasses. In this paper results are shown of femtosecond laser solarization experiments on a broad range of optical glasses from SCHOTT. The measurements have been performed by the Laser Zentrum Hannover in Germany. The results and their impact are discussed in comparison to traditional HOK-4 and UVA-B solarization measurements of the same materials. The target is to provide material selection guidance to the optical designer of beam shaping lens systems.

Ultralow dose effects in ion-beam induced grafting of polymethylmethacrylate (PMMA)

NASA Astrophysics Data System (ADS)

Corelli, J. C.; Steckl, A. J.; Pulver, D.; Randall, J. N.

We have investigated the process of image enhancement in high resolution lithography through polymer grafting techniques. Sensitivity gains of 10 3-10 4 were obtained for H +, X-ray, e-beam and deep-UV irradiations. Ultralow dose effects in 60 keV H + irradiated PMMA have been observed through the use of the acrylic acid (AA) monomer grafting with irradiated PMMA. At conventional doses of 10 10 cm -2 an inner structure of each feature is revealed. At doses of (1-2) X 10 9 cm -2, discrete events within the exposed regions are observable. This is the first time that individual events have been observable in a lithography process and sets the upper limit in the useful sensitivity of the resist and ion lithography process. This effect is directly observable only with ions, because of their higher efficiency per particle than either photons or electrons.

Enhanced light output from a nitride-based power chip of green light-emitting diodes with nano-rough surface using nanoimprint lithography.

PubMed

Huang, H W; Lin, C H; Yu, C C; Lee, B D; Chiu, C H; Lai, C F; Kuo, H C; Leung, K M; Lu, T C; Wang, S C

2008-05-07

Enhanced light extraction from a GaN-based power chip (PC) of green light-emitting diodes (LEDs) with a rough p-GaN surface using nanoimprint lithography is presented. At a driving current of 350 mA and with a chip size of 1 mm × 1 mm packaged on transistor outline (TO)-cans, the light output power of the green PC LEDs with nano-rough p-GaN surface is enhanced by 48% when compared with the same device without a rough p-GaN surface. In addition, by examining the radiation patterns, the green PC LED with nano-rough p-GaN surface shows stronger light extraction with a wider view angle. These results offer promising potential to enhance the light output powers of commercial light-emitting devices by using the technique of nanoimprint lithography under suitable nanopattern design.

Optical proximity correction (OPC) in near-field lithography with pixel-based field sectioning time modulation

NASA Astrophysics Data System (ADS)

Oh, Seonghyeon; Han, Dandan; Shim, Hyeon Bo; Hahn, Jae W.

2018-01-01

Subwavelength features have been successfully demonstrated in near-field lithography. In this study, the point spread function (PSF) of a near-field beam spot from a plasmonic ridge nanoaperture is discussed with regard to the complex decaying characteristic of a non-propagating wave and the asymmetry of the field distribution for pattern design. We relaxed the shape complexity of the field distribution with pixel-based optical proximity correction (OPC) for simplifying the pattern image distortion. To enhance the pattern fidelity for a variety of arbitrary patterns, field-sectioning structures are formulated via convolutions with a time-modulation function and a transient PSF along the near-field dominant direction. The sharpness of corners and edges, and line shortening can be improved by modifying the original target pattern shape using the proposed approach by considering both the pattern geometry and directionality of the field decay for OPC in near-field lithography.

Optical proximity correction (OPC) in near-field lithography with pixel-based field sectioning time modulation.

PubMed

Oh, Seonghyeon; Han, Dandan; Shim, Hyeon Bo; Hahn, Jae W

2018-01-26

Subwavelength features have been successfully demonstrated in near-field lithography. In this study, the point spread function (PSF) of a near-field beam spot from a plasmonic ridge nanoaperture is discussed with regard to the complex decaying characteristic of a non-propagating wave and the asymmetry of the field distribution for pattern design. We relaxed the shape complexity of the field distribution with pixel-based optical proximity correction (OPC) for simplifying the pattern image distortion. To enhance the pattern fidelity for a variety of arbitrary patterns, field-sectioning structures are formulated via convolutions with a time-modulation function and a transient PSF along the near-field dominant direction. The sharpness of corners and edges, and line shortening can be improved by modifying the original target pattern shape using the proposed approach by considering both the pattern geometry and directionality of the field decay for OPC in near-field lithography.

Stencil Nano Lithography Based on a Nanoscale Polymer Shadow Mask: Towards Organic Nanoelectronics

PubMed Central

Yun, Hoyeol; Kim, Sangwook; Kim, Hakseong; Lee, Junghyun; McAllister, Kirstie; Kim, Junhyung; Pyo, Sengmoon; Sung Kim, Jun; Campbell, Eleanor E. B.; Hyoung Lee, Wi; Wook Lee, Sang

2015-01-01

A stencil lithography technique has been developed to fabricate organic-material-based electronic devices with sub-micron resolution. Suspended polymethylmethacrylate (PMMA) membranes were used as shadow masks for defining organic channels and top electrodes. Arrays of pentacene field effect transistors (FETs) with various channel lengths from 50 μm down to 500 nm were successfully produced from the same batch using this technique. Electrical transport measurements showed that the electrical contacts of all devices were stable and the normalized contact resistances were much lower than previously studied organic FETs. Scaling effects, originating from the bulk space charge current, were investigated by analyzing the channel-length-dependent mobility and hysteresis behaviors. This novel lithography method provides a reliable means for studying the fundamental transport properties of organic materials at the nanoscale as well as enabling potential applications requiring the fabrication of integrated organic nanoelectronic devices. PMID:25959389

Stencil nano lithography based on a nanoscale polymer shadow mask: towards organic nanoelectronics.

PubMed

Yun, Hoyeol; Kim, Sangwook; Kim, Hakseong; Lee, Junghyun; McAllister, Kirstie; Kim, Junhyung; Pyo, Sengmoon; Sung Kim, Jun; Campbell, Eleanor E B; Hyoung Lee, Wi; Wook Lee, Sang

2015-05-11

A stencil lithography technique has been developed to fabricate organic-material-based electronic devices with sub-micron resolution. Suspended polymethylmethacrylate (PMMA) membranes were used as shadow masks for defining organic channels and top electrodes. Arrays of pentacene field effect transistors (FETs) with various channel lengths from 50 μm down to 500 nm were successfully produced from the same batch using this technique. Electrical transport measurements showed that the electrical contacts of all devices were stable and the normalized contact resistances were much lower than previously studied organic FETs. Scaling effects, originating from the bulk space charge current, were investigated by analyzing the channel-length-dependent mobility and hysteresis behaviors. This novel lithography method provides a reliable means for studying the fundamental transport properties of organic materials at the nanoscale as well as enabling potential applications requiring the fabrication of integrated organic nanoelectronic devices.

A combined electron beam/optical lithography process step for the fabrication of sub-half-micron-gate-length MMIC chips

NASA Technical Reports Server (NTRS)

Sewell, James S.; Bozada, Christopher A.

1994-01-01

Advanced radar and communication systems rely heavily on state-of-the-art microelectronics. Systems such as the phased-array radar require many transmit/receive (T/R) modules which are made up of many millimeter wave - microwave integrated circuits (MMIC's). The heart of a MMIC chip is the Gallium Arsenide (GaAs) field-effect transistor (FET). The transistor gate length is the critical feature that determines the operating frequency of the radar system. A smaller gate length will typically result in a higher frequency. In order to make a phased array radar system economically feasible, manufacturers must be capable of producing very large quantities of small-gate-length MMIC chips at a relatively low cost per chip. This requires the processing of a large number of wafers with a large number of chips per wafer, minimum processing time, and a very high chip yield. One of the bottlenecks in the fabrication of MIMIC chips is the transistor gate definition. The definition of sub-half-micron gates for GaAs-based field-effect transistors is generally performed by direct-write electron beam lithography (EBL). Because of the throughput limitations of EBL, the gate-layer fabrication is conventionally divided into two lithographic processes where EBL is used to generate the gate fingers and optical lithography is used to generate the large-area gate pads and interconnects. As a result, two complete sequences of resist application, exposure, development, metallization and lift-off are required for the entire gate structure. We have baselined a hybrid process, referred to as EBOL (electron beam/optical lithography), in which a single application of a multi-level resist is used for both exposures. The entire gate structure, (gate fingers, interconnects and pads), is then formed with a single metallization and lift-off process. The EBOL process thus retains the advantages of the high-resolution E-beam lithography and the high throughput of optical lithography while essentially eliminating an entire lithography/metallization/lift-off process sequence. This technique has been proven to be reliable for both trapezoidal and mushroom gates and has been successfully applied to metal-semiconductor and high-electron-mobility field-effect transistor (MESFET and HEMT) wafers containing devices with gate lengths down to 0.10 micron and 75 x 75 micron gate pads. The yields and throughput of these wafers have been very high with no loss in device performance. We will discuss the entire EBOL process technology including the multilayer resist structure, exposure conditions, process sensitivities, metal edge definition, device results, comparison to the standard gate-layer process, and its suitability for manufacturing.

A combined electron beam/optical lithography process step for the fabrication of sub-half-micron-gate-length MMIC chips

NASA Astrophysics Data System (ADS)

Sewell, James S.; Bozada, Christopher A.

1994-02-01

Advanced radar and communication systems rely heavily on state-of-the-art microelectronics. Systems such as the phased-array radar require many transmit/receive (T/R) modules which are made up of many millimeter wave - microwave integrated circuits (MMIC's). The heart of a MMIC chip is the Gallium Arsenide (GaAs) field-effect transistor (FET). The transistor gate length is the critical feature that determines the operating frequency of the radar system. A smaller gate length will typically result in a higher frequency. In order to make a phased array radar system economically feasible, manufacturers must be capable of producing very large quantities of small-gate-length MMIC chips at a relatively low cost per chip. This requires the processing of a large number of wafers with a large number of chips per wafer, minimum processing time, and a very high chip yield. One of the bottlenecks in the fabrication of MIMIC chips is the transistor gate definition. The definition of sub-half-micron gates for GaAs-based field-effect transistors is generally performed by direct-write electron beam lithography (EBL). Because of the throughput limitations of EBL, the gate-layer fabrication is conventionally divided into two lithographic processes where EBL is used to generate the gate fingers and optical lithography is used to generate the large-area gate pads and interconnects. As a result, two complete sequences of resist application, exposure, development, metallization and lift-off are required for the entire gate structure. We have baselined a hybrid process, referred to as EBOL (electron beam/optical lithography), in which a single application of a multi-level resist is used for both exposures. The entire gate structure, (gate fingers, interconnects and pads), is then formed with a single metallization and lift-off process. The EBOL process thus retains the advantages of the high-resolution E-beam lithography and the high throughput of optical lithography while essentially eliminating an entire lithography/metallization/lift-off process sequence. This technique has been proven to be reliable for both trapezoidal and mushroom gates and has been successfully applied to metal-semiconductor and high-electron-mobility field-effect transistor (MESFET and HEMT) wafers containing devices with gate lengths down to 0.10 micron and 75 x 75 micron gate pads. The yields and throughput of these wafers have been very high with no loss in device performance. We will discuss the entire EBOL process technology including the multilayer resist structure, exposure conditions, process sensitivities, metal edge definition, device results, comparison to the standard gate-layer process, and its suitability for manufacturing.

Compensation for Lithography Induced Process Variations during Physical Design

NASA Astrophysics Data System (ADS)

Chin, Eric Yiow-Bing

This dissertation addresses the challenge of designing robust integrated circuits in the deep sub micron regime in the presence of lithography process variability. By extending and combining existing process and circuit analysis techniques, flexible software frameworks are developed to provide detailed studies of circuit performance in the presence of lithography variations such as focus and exposure. Applications of these software frameworks to select circuits demonstrate the electrical impact of these variations and provide insight into variability aware compact models that capture the process dependent circuit behavior. These variability aware timing models abstract lithography variability from the process level to the circuit level and are used to estimate path level circuit performance with high accuracy with very little overhead in runtime. The Interconnect Variability Characterization (IVC) framework maps lithography induced geometrical variations at the interconnect level to electrical delay variations. This framework is applied to one dimensional repeater circuits patterned with both 90nm single patterning and 32nm double patterning technologies, under the presence of focus, exposure, and overlay variability. Studies indicate that single and double patterning layouts generally exhibit small variations in delay (between 1--3%) due to self compensating RC effects associated with dense layouts and overlay errors for layouts without self-compensating RC effects. The delay response of each double patterned interconnect structure is fit with a second order polynomial model with focus, exposure, and misalignment parameters with 12 coefficients and residuals of less than 0.1ps. The IVC framework is also applied to a repeater circuit with cascaded interconnect structures to emulate more complex layout scenarios, and it is observed that the variations on each segment average out to reduce the overall delay variation. The Standard Cell Variability Characterization (SCVC) framework advances existing layout-level lithography aware circuit analysis by extending it to cell-level applications utilizing a physically accurate approach that integrates process simulation, compact transistor models, and circuit simulation to characterize electrical cell behavior. This framework is applied to combinational and sequential cells in the Nangate 45nm Open Cell Library, and the timing response of these cells to lithography focus and exposure variations demonstrate Bossung like behavior. This behavior permits the process parameter dependent response to be captured in a nine term variability aware compact model based on Bossung fitting equations. For a two input NAND gate, the variability aware compact model captures the simulated response to an accuracy of 0.3%. The SCVC framework is also applied to investigate advanced process effects including misalignment and layout proximity. The abstraction of process variability from the layout level to the cell level opens up an entire new realm of circuit analysis and optimization and provides a foundation for path level variability analysis without the computationally expensive costs associated with joint process and circuit simulation. The SCVC framework is used with slight modification to illustrate the speedup and accuracy tradeoffs of using compact models. With variability aware compact models, the process dependent performance of a three stage logic circuit can be estimated to an accuracy of 0.7% with a speedup of over 50,000. Path level variability analysis also provides an accurate estimate (within 1%) of ring oscillator period in well under a second. Another significant advantage of variability aware compact models is that they can be easily incorporated into existing design methodologies for design optimization. This is demonstrated by applying cell swapping on a logic circuit to reduce the overall delay variability along a circuit path. By including these variability aware compact models in cell characterization libraries, design metrics such as circuit timing, power, area, and delay variability can be quickly assessed to optimize for the correct balance of all design metrics, including delay variability. Deterministic lithography variations can be easily captured using the variability aware compact models described in this dissertation. However, another prominent source of variability is random dopant fluctuations, which affect transistor threshold voltage and in turn circuit performance. The SCVC framework is utilized to investigate the interactions between deterministic lithography variations and random dopant fluctuations. Monte Carlo studies show that the output delay distribution in the presence of random dopant fluctuations is dependent on lithography focus and exposure conditions, with a 3.6 ps change in standard deviation across the focus exposure process window. This indicates that the electrical impact of random variations is dependent on systematic lithography variations, and this dependency should be included for precise analysis.

From Monochrome to Technicolor: Simple Generic Approaches to Multicomponent Protein Nanopatterning Using Siloxanes with Photoremovable Protein-Resistant Protecting Groups

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

El Zubir, Osama; Xia, Sijing; Ducker, Robert E.

We show that sequential protein deposition is possible by photodeprotection of films formed from a tetraethylene-glycol functionalized nitrophenylethoxycarbonyl-protected aminopropyltriethoxysilane (NPEOC-APTES). Exposure to near-UV irradiation removes the protein-resistant protecting group, and allows protein adsorption onto the resulting aminated surface. The protein resistance was tested using proteins with fluorescent labels and microspectroscopy of two-component structures formed by micro- and nanopatterning and deposition of yellow and green fluorescent proteins (YFP/GFP). Nonspecific adsorption onto regions where the protecting group remained intact was negligible. Multiple component patterns were also formed by near-field methods. Because reading and writing can be decoupled in a near-field microscope, itmore » is possible to carry out sequential patterning steps at a single location involving different proteins. Up to four different proteins were formed into geometric patterns using near-field lithography. Interferometric lithography facilitates the organization of proteins over square cm areas. Two-component patterns consisting of 150 nm streptavidin dots formed within an orthogonal grid of bars of GFP at a period of ca. 500 nm could just be resolved by fluorescence microscopy.« less

From Monochrome to Technicolor: Simple Generic Approaches to Multicomponent Protein Nanopatterning Using Siloxanes with Photoremovable Protein-Resistant Protecting Groups

DOE PAGES

El Zubir, Osama; Xia, Sijing; Ducker, Robert E.; ...

2017-05-27

We show that sequential protein deposition is possible by photodeprotection of films formed from a tetraethylene-glycol functionalized nitrophenylethoxycarbonyl-protected aminopropyltriethoxysilane (NPEOC-APTES). Exposure to near-UV irradiation removes the protein-resistant protecting group, and allows protein adsorption onto the resulting aminated surface. The protein resistance was tested using proteins with fluorescent labels and microspectroscopy of two-component structures formed by micro- and nanopatterning and deposition of yellow and green fluorescent proteins (YFP/GFP). Nonspecific adsorption onto regions where the protecting group remained intact was negligible. Multiple component patterns were also formed by near-field methods. Because reading and writing can be decoupled in a near-field microscope, itmore » is possible to carry out sequential patterning steps at a single location involving different proteins. Up to four different proteins were formed into geometric patterns using near-field lithography. Interferometric lithography facilitates the organization of proteins over square cm areas. Two-component patterns consisting of 150 nm streptavidin dots formed within an orthogonal grid of bars of GFP at a period of ca. 500 nm could just be resolved by fluorescence microscopy.« less

Positioning performance of a maglev fine positioning system

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

Wronosky, J.B.; Smith, T.G.; Jordan, J.D.

1996-12-01

A wafer positioning system was recently developed by Sandia National Laboratories for an Extreme Ultraviolet Lithography (EUVL) research tool. The system, which utilizes a magnetically levitated fine stage to provide ultra-precise positioning in all six degrees of freedom, incorporates technological improvements resulting from four years of prototype development experience. System enhancements, implemented on a second generation design for an ARPA National Center for Advanced Information Component Manufacturing (NCAICM) project, introduced active structural control for the levitated structure of the system. Magnetic levitation (maglev) is emerging as an important technology for wafer positioning systems in advanced lithography applications. The advantages ofmore » maglev stem from the absence of physical contact. The resulting lack of friction enables accurate, fast positioning. Maglev systems are mechanically simple, accomplishing full six degree-of-freedom suspension and control with a minimum of moving parts. Power-efficient designs, which reduce the possibility of thermal distortion of the platen, are achievable. Manufacturing throughput will be improved in future systems with the addition of active structural control of the positioning stages. This paper describes the design, implementation, and functional capability of the maglev fine positioning system. Specifics regarding performance design goals and test results are presented.« less

Study of nanoimprint lithography (NIL) for HVM of memory devices

NASA Astrophysics Data System (ADS)

Kono, Takuya; Hatano, Masayuki; Tokue, Hiroshi; Kobayashi, Kei; Suzuki, Masato; Fukuhara, Kazuya; Asano, Masafumi; Nakasugi, Tetsuro; Choi, Eun Hyuk; Jung, Wooyung

2017-03-01

A low cost alternative lithographic technology is desired to meet the decreasing feature size of semiconductor devices. Nano-imprint lithography (NIL) is one of the candidates for alternative lithographic technologies.[1][2][3] NIL has such advantages as good resolution, critical dimension (CD) uniformity and low line edge roughness (LER). On the other hand, the critical issues of NIL are defectivity, overlay, and throughput. In order to introduce NIL into the HVM, it is necessary to overcome these three challenges simultaneously.[4]-[12] In our previous study, we have reported a dramatic improvement in NIL process defectivity on a pilot line tool, FPA-1100 NZ2. We have described that the NIL process for 2x nm half pitch is getting closer to the target of HVM.[12] In this study, we report the recent evaluation of the NIL process performance to judge the applicability of NIL to memory device fabrications. In detail, the CD uniformity and LER are found to be less than 2nm. The overlay accuracy of the test device is less than 7nm. A defectivity level of below 1pcs./cm2 has been achieved at a throughput of 15 wafers per hour.

Design of an integrated aerial image sensor

NASA Astrophysics Data System (ADS)

Xue, Jing; Spanos, Costas J.

2005-05-01

The subject of this paper is a novel integrated aerial image sensor (IAIS) system suitable for integration within the surface of an autonomous test wafer. The IAIS could be used as a lithography processing monitor, affording a "wafer's eye view" of the process, and therefore facilitating advanced process control and diagnostics without integrating (and dedicating) the sensor to the processing equipment. The IAIS is composed of an aperture mask and an array of photo-detectors. In order to retrieve nanometer scale resolution of the aerial image with a practical photo-detector pixel size, we propose a design of an aperture mask involving a series of spatial phase "moving" aperture groups. We demonstrate a design example aimed at the 65nm technology node through TEMPEST simulation. The optimized, key design parameters include an aperture width in the range of 30nm, aperture thickness in the range of 70nm, and offer a spatial resolution of about 5nm, all with comfortable fabrication tolerances. Our preliminary simulation work indicates the possibility of the IAIS being applied to the immersion lithography. A bench-top far-field experiment verifies that our approach of the spatial frequency down-shift through forming large Moire patterns is feasible.

Wafer-scale micro-optics fabrication

NASA Astrophysics Data System (ADS)

Voelkel, Reinhard

2012-07-01

Micro-optics is an indispensable key enabling technology for many products and applications today. Probably the most prestigious examples are the diffractive light shaping elements used in high-end DUV lithography steppers. Highly-efficient refractive and diffractive micro-optical elements are used for precise beam and pupil shaping. Micro-optics had a major impact on the reduction of aberrations and diffraction effects in projection lithography, allowing a resolution enhancement from 250 nm to 45 nm within the past decade. Micro-optics also plays a decisive role in medical devices (endoscopes, ophthalmology), in all laser-based devices and fiber communication networks, bringing high-speed internet to our homes. Even our modern smart phones contain a variety of micro-optical elements. For example, LED flash light shaping elements, the secondary camera, ambient light and proximity sensors. Wherever light is involved, micro-optics offers the chance to further miniaturize a device, to improve its performance, or to reduce manufacturing and packaging costs. Wafer-scale micro-optics fabrication is based on technology established by the semiconductor industry. Thousands of components are fabricated in parallel on a wafer. This review paper recapitulates major steps and inventions in wafer-scale micro-optics technology. The state-of-the-art of fabrication, testing and packaging technology is summarized.

Direct write electron beam lithography: a historical overview

NASA Astrophysics Data System (ADS)

Pfeiffer, Hans C.

2010-09-01

Maskless pattern generation capability in combination with practically limitless resolution made probe-forming electron beam systems attractive tools in the semiconductor fabrication process. However, serial exposure of pattern elements with a scanning beam is a slow process and throughput presented a key challenge in electron beam lithography from the beginning. To meet this challenge imaging concepts with increasing exposure efficiency have been developed projecting ever larger number of pixels in parallel. This evolution started in the 1960s with the SEM-type Gaussian beam systems writing one pixel at a time directly on wafers. During the 1970s IBM pioneered the concept of shaped beams containing multiple pixels which led to higher throughput and an early success of e-beam direct write (EBDW) in large scale manufacturing of semiconductor chips. EBDW in a mix-and match approach with optical lithography provided unique flexibility in part number management and cycle time reduction and proved extremely cost effective in IBM's Quick-Turn-Around-Time (QTAT) facilities. But shaped beams did not keep pace with Moore's law because of limitations imposed by the physics of charged particles: Coulomb interactions between beam electrons cause image blur and consequently limit beam current and throughput. A new technology approach was needed. Physically separating beam electrons into multiple beamlets to reduce Coulomb interaction led to the development of massively parallel projection of pixels. Electron projection lithography (EPL) - a mask based imaging technique emulating optical steppers - was pursued during the 1990s by Bell Labs with SCALPEL and by IBM with PREVAIL in partnership with Nikon. In 2003 Nikon shipped the first NCR-EB1A e-beam stepper based on the PREVAIL technology to Selete. It exposed pattern segments containing 10 million pixels in single shot and represented the first successful demonstration of massively parallel pixel projection. However the window of opportunity for EPL had closed with the quick implementation of immersion lithography and the interest of the industry has since shifted back to maskless lithography (ML2). This historical overview of EBDW will highlight opportunities and limitation of the technology with particular focus on technical challenges facing the current ML2 development efforts in Europe and the US. A brief status report and risk assessment of the ML2 approaches will be provided.

Software-based data path for raster-scanned multi-beam mask lithography

NASA Astrophysics Data System (ADS)

Rajagopalan, Archana; Agarwal, Ankita; Buck, Peter; Geller, Paul; Hamaker, H. Christopher; Rao, Nagswara

2016-10-01

According to the 2013 SEMATECH Mask Industry Survey,i roughly half of all photomasks are produced using laser mask pattern generator ("LMPG") lithography. LMPG lithography can be used for all layers at mature technology nodes, and for many non-critical and semi-critical masks at advanced nodes. The extensive use of multi-patterning at the 14-nm node significantly increases the number of critical mask layers, and the transition in wafer lithography from positive tone resist to negative tone resist at the 14-nm design node enables the switch from advanced binary masks back to attenuated phase shifting masks that require second level writes to remove unwanted chrome. LMPG lithography is typically used for second level writes due to its high productivity, absence of charging effects, and versatile non-actinic alignment capability. As multi-patterning use expands from double to triple patterning and beyond, the number of LMPG second level writes increases correspondingly. The desire to reserve the limited capacity of advanced electron beam writers for use when essential is another factor driving the demand for LMPG capacity. The increasing demand for cost-effective productivity has kept most of the laser mask writers ever manufactured running in production, sometimes long past their projected lifespan, and new writers continue to be built based on hardware developed some years ago.ii The data path is a case in point. While state-ofthe- art when first introduced, hardware-based data path systems are difficult to modify or add new features to meet the changing requirements of the market. As data volumes increase, design styles change, and new uses are found for laser writers, it is useful to consider a replacement for this critical subsystem. The availability of low-cost, high-performance, distributed computer systems combined with highly scalable EDA software lends itself well to creating an advanced data path system. EDA software, in routine production today, scales well to hundreds or even thousands of CPU-cores, offering the potential for virtually unlimited capacity. Features available in EDA software such as sizing, scaling, tone reversal, OPC, MPC, rasterization, and others are easily adapted to the requirements of a data path system. This paper presents the motivation, requirements, design and performance of an advanced, scalable software data path system suitable to support multi-beam laser mask lithography.

Lossless compression algorithm for REBL direct-write e-beam lithography system

NASA Astrophysics Data System (ADS)

Cramer, George; Liu, Hsin-I.; Zakhor, Avideh

2010-03-01

Future lithography systems must produce microchips with smaller feature sizes, while maintaining throughputs comparable to those of today's optical lithography systems. This places stringent constraints on the effective data throughput of any maskless lithography system. In recent years, we have developed a datapath architecture for direct-write lithography systems, and have shown that compression plays a key role in reducing throughput requirements of such systems. Our approach integrates a low complexity hardware-based decoder with the writers, in order to decompress a compressed data layer in real time on the fly. In doing so, we have developed a spectrum of lossless compression algorithms for integrated circuit layout data to provide a tradeoff between compression efficiency and hardware complexity, the latest of which is Block Golomb Context Copy Coding (Block GC3). In this paper, we present a modified version of Block GC3 called Block RGC3, specifically tailored to the REBL direct-write E-beam lithography system. Two characteristic features of the REBL system are a rotary stage resulting in arbitrarily-rotated layout imagery, and E-beam corrections prior to writing the data, both of which present significant challenges to lossless compression algorithms. Together, these effects reduce the effectiveness of both the copy and predict compression methods within Block GC3. Similar to Block GC3, our newly proposed technique Block RGC3, divides the image into a grid of two-dimensional "blocks" of pixels, each of which copies from a specified location in a history buffer of recently-decoded pixels. However, in Block RGC3 the number of possible copy locations is significantly increased, so as to allow repetition to be discovered along any angle of orientation, rather than horizontal or vertical. Also, by copying smaller groups of pixels at a time, repetition in layout patterns is easier to find and take advantage of. As a side effect, this increases the total number of copy locations to transmit; this is combated with an extra region-growing step, which enforces spatial coherence among neighboring copy locations, thereby improving compression efficiency. We characterize the performance of Block RGC3 in terms of compression efficiency and encoding complexity on a number of rotated Metal 1, Poly, and Via layouts at various angles, and show that Block RGC3 provides higher compression efficiency than existing lossless compression algorithms, including JPEG-LS, ZIP, BZIP2, and Block GC3.

Topography preserved microwave plasma etching for top-down layer engineering in MoS2 and other van der Waals materials.

PubMed

Varghese, Abin; Sharma, Chithra H; Thalakulam, Madhu

2017-03-17

A generic and universal layer engineering strategy for van der Waals (vW) materials, scalable and compatible with the current semiconductor technology, is of paramount importance in realizing all-two-dimensional logic circuits and to move beyond the silicon scaling limit. In this letter, we demonstrate a scalable and highly controllable microwave plasma based layer engineering strategy for MoS 2 and other vW materials. Using this technique we etch MoS 2 flakes layer-by-layer starting from an arbitrary thickness and area down to the mono- or the few-layer limit. From Raman spectroscopy, atomic force microscopy, photoluminescence spectroscopy, scanning electron microscopy and transmission electron microscopy, we confirm that the structural and morphological properties of the material have not been compromised. The process preserves the pre-etch layer topography and yields a smooth and pristine-like surface. We explore the electrical properties utilising a field effect transistor geometry and find that the mobility values of our samples are comparable to those of the pristine ones. The layer removal does not involve any reactive gasses or chemical reactions and relies on breaking the weak inter-layer vW interaction making it a generic technique for a wide spectrum of layered materials and heterostructures. We demonstrate the wide applicability of the technique by extending it to other systems such as graphene, h-BN and WSe 2 . In addition, using microwave plasma in combination with standard lithography, we illustrate a lateral patterning scheme making this process a potential candidate for large scale device fabrication in addition to layer engineering.

Retrieve polarization aberration from image degradation: a new measurement method in DUV lithography

NASA Astrophysics Data System (ADS)

Xiang, Zhongbo; Li, Yanqiu

2017-10-01

Detailed knowledge of polarization aberration (PA) of projection lens in higher-NA DUV lithographic imaging is necessary due to its impact to imaging degradations, and precise measurement of PA is conductive to computational lithography techniques such as RET and OPC. Current in situ measurement method of PA thorough the detection of degradations of aerial images need to do linear approximation and apply the assumption of 3-beam/2-beam interference condition. The former approximation neglects the coupling effect of the PA coefficients, which would significantly influence the accuracy of PA retrieving. The latter assumption restricts the feasible pitch of test masks in higher-NA system, conflicts with the Kirhhoff diffraction model of test mask used in retrieving model, and introduces 3D mask effect as a source of retrieving error. In this paper, a new in situ measurement method of PA is proposed. It establishes the analytical quadratic relation between the PA coefficients and the degradations of aerial images of one-dimensional dense lines in coherent illumination through vector aerial imaging, which does not rely on the assumption of 3-beam/2- beam interference and linear approximation. In this case, the retrieval of PA from image degradation can be convert from the nonlinear system of m-quadratic equations to a multi-objective quadratic optimization problem, and finally be solved by nonlinear least square method. Some preliminary simulation results are given to demonstrate the correctness and accuracy of the new PA retrieving model.

SETA Support for the DARPA Microelectronics Technology Insertion Program of the Microelectronics Technology Office

DTIC Science & Technology

1992-08-17

Conclusions. Key personnel planned and administered the 193-nm lithography SBIR workshop on May 7, 1992 as well as planned the GaAs Insertion...converters can use Josephson junctions (JJ) to improve performance. Superconductive quantum interference devices (SQUIDs), such as JJs, are used to form...forward control of a lithography stepper. Mark Conner at Booz-Allen has copies of the charts. You should take a few minutes to review them. I asked Costos

Architecture and Hardware Design of Lossless Compression Algorithms for Direct-Write Maskless Lithography Systems

DTIC Science & Technology

2010-04-29

magnitude greater than today’s high-definition video coding standards. Moreover, the micromirror devices of maskless lithography are smaller than those...be found in the literature [33]. In this architecture, the optical source flashes on a writer system, which consists of a micromirror array and a...the writer system. Due to the physical dimension constraints of the micromirror array and writer system, an entire wafer can be written in a few

Scalable fabrication of strongly textured organic semiconductor micropatterns by capillary force lithography.

PubMed

Jo, Pil Sung; Vailionis, Arturas; Park, Young Min; Salleo, Alberto

2012-06-26

Strongly textured organic semiconductor micropatterns made of the small molecule dioctylbenzothienobenzothiophene (C(8)-BTBT) are fabricated by using a method based on capillary force lithography (CFL). This technique provides the C(8)-BTBT solution with nucleation sites for directional growth, and can be used as a scalable way to produce high quality crystalline arrays in desired regions of a substrate for OFET applications. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Maskless micro-ion-beam reduction lithography system

DOEpatents

Leung, Ka-Ngo; Barletta, William A.; Patterson, David O.; Gough, Richard A.

2005-05-03

A maskless micro-ion-beam reduction lithography system is a system for projecting patterns onto a resist layer on a wafer with feature size down to below 100 nm. The MMRL system operates without a stencil mask. The patterns are generated by switching beamlets on and off from a two electrode blanking system or pattern generator. The pattern generator controllably extracts the beamlet pattern from an ion source and is followed by a beam reduction and acceleration column.

A novel methodology for litho-to-etch pattern fidelity correction for SADP process

NASA Astrophysics Data System (ADS)

Chen, Shr-Jia; Chang, Yu-Cheng; Lin, Arthur; Chang, Yi-Shiang; Lin, Chia-Chi; Lai, Jun-Cheng

2017-03-01

For 2x nm node semiconductor devices and beyond, more aggressive resolution enhancement techniques (RETs) such as source-mask co-optimization (SMO), litho-etch-litho-etch (LELE) and self-aligned double patterning (SADP) are utilized for the low k1 factor lithography processes. In the SADP process, the pattern fidelity is extremely critical since a slight photoresist (PR) top-loss or profile roughness may impact the later core trim process, due to its sensitivity to environment. During the subsequent sidewall formation and core removal processes, the core trim profile weakness may worsen and induces serious defects that affect the final electrical performance. To predict PR top-loss, a rigorous lithography simulation can provide a reference to modify mask layouts; but it takes a much longer run time and is not capable of full-field mask data preparation. In this paper, we first brought out an algorithm which utilizes multi-intensity levels from conventional aerial image simulation to assess the physical profile through lithography to core trim etching steps. Subsequently, a novel correction method was utilized to improve the post-etch pattern fidelity without the litho. process window suffering. The results not only matched PR top-loss in rigorous lithography simulation, but also agreed with post-etch wafer data. Furthermore, this methodology can also be incorporated with OPC and post-OPC verification to improve core trim profile and final pattern fidelity at an early stage.

Mask strategy at International SEMATECH

NASA Astrophysics Data System (ADS)

Kimmel, Kurt R.

2002-08-01

International SEMATECH (ISMT) is a consortium consisting of 13 leading semiconductor manufacturers from around the globe. Its objective is to develop the infrastructure necessary for its member companies to realize the International Technology Roadmap for Semiconductors (ITRS) through efficiencies of shared development resources and knowledge. The largest area of effort is lithography, recognized as a crucial enabler for microelectronics technology progress. Within the Lithography Division, most of the efforts center on mask-related issues. The development strategy at International SEMATCH will be presented and the interlock of lithography projects clarified. Because of the limited size of the mask production equipment market, the business case is weak for aggressive investment commensurate with the pace of the International Technology Roadmap for Semiconductors. With masks becoming the overwhelming component of lithography cost, new ways of reducing or eliminating mask costs are being explored. Will mask technology survive without a strong business case? Will the mask industry limit the growth of the semiconductor industry? Are advanced masks worth their escalating cost? An analysis of mask cost from the perspective of mask value imparted to the user is presented with examples and generic formulas for the reader to apply independently. A key part to the success for both International SEMATECH and the industry globally will be partnerships on both the local level between mask-maker and mask-user, and the macro level where global collaborations will be necessary to resolve technology development cost challenges.

REBL: design progress toward 16 nm half-pitch maskless projection electron beam lithography

NASA Astrophysics Data System (ADS)

McCord, Mark A.; Petric, Paul; Ummethala, Upendra; Carroll, Allen; Kojima, Shinichi; Grella, Luca; Shriyan, Sameet; Rettner, Charles T.; Bevis, Chris F.

2012-03-01

REBL (Reflective Electron Beam Lithography) is a novel concept for high speed maskless projection electron beam lithography. Originally targeting 45 nm HP (half pitch) under a DARPA funded contract, we are now working on optimizing the optics and architecture for the commercial silicon integrated circuit fabrication market at the equivalent of 16 nm HP. The shift to smaller features requires innovation in most major subsystems of the tool, including optics, stage, and metrology. We also require better simulation and understanding of the exposure process. In order to meet blur requirements for 16 nm lithography, we are both shrinking the pixel size and reducing the beam current. Throughput will be maintained by increasing the number of columns as well as other design optimizations. In consequence, the maximum stage speed required to meet wafer throughput targets at 16 nm will be much less than originally planned for at 45 nm. As a result, we are changing the stage architecture from a rotary design to a linear design that can still meet the throughput requirements but with more conventional technology that entails less technical risk. The linear concept also allows for simplifications in the datapath, primarily from being able to reuse pattern data across dies and columns. Finally, we are now able to demonstrate working dynamic pattern generator (DPG) chips, CMOS chips with microfabricated lenslets on top to prevent crosstalk between pixels.

Robust resolution enhancement optimization methods to process variations based on vector imaging model

NASA Astrophysics Data System (ADS)

Ma, Xu; Li, Yanqiu; Guo, Xuejia; Dong, Lisong

2012-03-01

Optical proximity correction (OPC) and phase shifting mask (PSM) are the most widely used resolution enhancement techniques (RET) in the semiconductor industry. Recently, a set of OPC and PSM optimization algorithms have been developed to solve for the inverse lithography problem, which are only designed for the nominal imaging parameters without giving sufficient attention to the process variations due to the aberrations, defocus and dose variation. However, the effects of process variations existing in the practical optical lithography systems become more pronounced as the critical dimension (CD) continuously shrinks. On the other hand, the lithography systems with larger NA (NA>0.6) are now extensively used, rendering the scalar imaging models inadequate to describe the vector nature of the electromagnetic field in the current optical lithography systems. In order to tackle the above problems, this paper focuses on developing robust gradient-based OPC and PSM optimization algorithms to the process variations under a vector imaging model. To achieve this goal, an integrative and analytic vector imaging model is applied to formulate the optimization problem, where the effects of process variations are explicitly incorporated in the optimization framework. The steepest descent algorithm is used to optimize the mask iteratively. In order to improve the efficiency of the proposed algorithms, a set of algorithm acceleration techniques (AAT) are exploited during the optimization procedure.

Surface phenomena related to mirror degradation in extreme ultraviolet (EUV) lithography

NASA Astrophysics Data System (ADS)

Madey, Theodore E.; Faradzhev, Nadir S.; Yakshinskiy, Boris V.; Edwards, N. V.

2006-12-01

One of the most promising methods for next generation device manufacturing is extreme ultraviolet (EUV) lithography, which uses 13.5 nm wavelength radiation generated from freestanding plasma-based sources. The short wavelength of the incident illumination allows for a considerable decrease in printed feature size, but also creates a range of technological challenges not present for traditional optical lithography. Contamination and oxidation form on multilayer reflecting optics surfaces that not only reduce system throughput because of the associated reduction in EUV reflectivity, but also introduce wavefront aberrations that compromise the ability to print uniform features. Capping layers of ruthenium, films ∼2 nm thick, are found to extend the lifetime of Mo/Si multilayer mirrors used in EUV lithography applications. However, reflectivities of even the Ru-coated mirrors degrade in time during exposure to EUV radiation. Ruthenium surfaces are chemically reactive and are very effective as heterogeneous catalysts. In the present paper we summarize the thermal and radiation-induced surface chemistry of bare Ru exposed to gases; the emphasis is on H2O vapor, a dominant background gas in vacuum processing chambers. Our goal is to provide insights into the fundamental physical processes that affect the reflectivity of Ru-coated Mo/Si multilayer mirrors exposed to EUV radiation. Our ultimate goal is to identify and recommend practices or antidotes that may extend mirror lifetimes.

Fabrication of three-dimensional millimeter-height structures using direct ultraviolet lithography on liquid-state photoresist for simple and fast manufacturing

NASA Astrophysics Data System (ADS)

Kim, Jungkwun; Yoon, Yong-Kyu

2015-07-01

A rapid three-dimensional (3-D) ultraviolet (UV) lithography process for the fabrication of millimeter-tall high aspect ratio complex structures is presented. The liquid-state negative-tone photosensitive polyurethane, LF55GN, has been directly photopatterned using multidirectionally projected UV light for 3-D micropattern formation. The proposed lithographic scheme enabled us to overcome the maximum height obtained with a photopatternable epoxy, SU8, which has been conventionally most commonly used for the fabrication of tall and high aspect ratio microstructures. Also, the fabrication process time has been significantly reduced by eliminating photoresist-baking steps. Computer-controlled multidirectional UV lithography has been employed to fabricate 3-D structures, where the UV-exposure substrate is dynamically tilt-rotating during UV exposure to create various 3-D ray traces in the polyurethane layer. LF55GN has been characterized to provide feasible fabrication conditions for the multidirectional UV lithography. Very tall structures including a 6-mm tall triangular slab and a 5-mm tall hexablaze have been successfully fabricated. A 4.5-mm tall air-lifted polymer-core bowtie monopole antenna, which is the tallest monopole structure fabricated by photolithography and subsequent metallization, has been successfully demonstrated. The antenna shows a resonant radiation frequency of 12.34 GHz, a return loss of 36 dB, and a 10 dB bandwidth of 7%.

Nano-imprint lithography using poly (methyl methacrylate) (PMMA) and polystyrene (PS) polymers

NASA Astrophysics Data System (ADS)

Ting, Yung-Chiang; Shy, Shyi-Long

2016-04-01

Nano-imprinting lithography (NIL) technology, as one of the most promising fabrication technologies, has been demonstrated to be a powerful tool for large-area replication up to wafer-level, with features down to nanometer scale. The cost of resists used for NIL is important for wafer-level large-area replication. This study aims to develop capabilities in patterning larger area structure using thermal NIL. The commercial available Poly (Methyl Methacrylate) (PMMA) and Polystyrene (PS) polymers possess a variety of characteristics desirable for NIL, such as low material cost, low bulkvolumetric shrinkage, high spin coating thickness uniformity, high process stability, and acceptable dry-etch resistance. PMMA materials have been utilized for positive electron beam lithography for many years, offering high resolution capability and wide process latitude. In addition, it is preferable to have a negative resist like PMMA, which is a simple polymer with low cost and practically unlimited shelf life, and can be dissolved easily using commercial available Propylene glycol methyl ether acetate (PGMEA) safer solvent to give the preferred film thickness. PS is such a resist, as it undergoes crosslinking when exposed to deep UV light or an electron beam and can be used for NIL. The result is a cost effective patterning larger area structure using thermal nano-imprint lithography (NIL) by using commercial available PMMA and PS ploymers as NIL resists.

A simplified method for generating periodic nanostructures by interference lithography without the use of an anti-reflection coating

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

Kapon, Omree; Muallem, Merav; Palatnik, Alex

Interference lithography has proven to be a useful technique for generating periodic sub-diffraction limited nanostructures. Interference lithography can be implemented by exposing a photoresist polymer to laser light using a two-beam arrangement or more simply a one beam configuration based on a Lloyd's Mirror Interferometer. For typical photoresist layers, an anti-reflection coating must be deposited on the substrate to prevent adverse reflections from cancelling the holographic pattern of the interfering beams. For silicon substrates, such coatings are typically multilayered and complex in composition. By thinning the photoresist layer to a thickness well below the quarter wavelength of the exposing beam,more » we demonstrate that interference gratings can be generated without an anti-reflection coating on the substrate. We used ammonium dichromate doped polyvinyl alcohol as the positive photoresist because it provides excellent pinhole free layers down to thicknesses of 40 nm, and can be cross-linked by a low-cost single mode 457 nm laser, and can be etched in water. Gratings with a period of 320 nm and depth of 4 nm were realized, as well as a variety of morphologies depending on the photoresist thickness. This simplified interference lithography technique promises to be useful for generating periodic nanostructures with high fidelity and minimal substrate treatments.« less

157-nm photomask handling and infrastructure: requirements and feasibility

NASA Astrophysics Data System (ADS)

Cullins, Jerry; Muzio, Edward G.

2001-09-01

Photomask handling is significantly more challenging for 157nm lithography than for any previous generation of optical lithography. First, pellicle materials are not currently available which meet all the requirements for 157nm lithography. Polymeric materials used at 193nm higher wavelengths are not transmissive at 157nm, while modified fused silica materials have adequate transmission and durability but have mechanical issues that need to be resolved. Second, the problem of molecular level contamination on the reticle must be solved. This contamination is due to the presence of oxygen, carbon dioxide, water, and other attenuators of 157nm radiation on the mask surface. It must be removed using something other than the lithography laser due to throughput and cost of ownership considerations. Third, there is the issue of removing attenuators from under the pellicle after a material becomes available. Both the ambient atmosphere and other introduced contaminants must be removed from the space between the reticle and pellicle after cleaning but before exposure. Forth are the potential issues for storage of reticles both during transportation from the mask shop and after it is in the wafer fab. Finally, the problems associated with operating in an optically inert dry environment must be addressed. The lack of moisture in the environment removes one of the key electrical discharge paths off of the reticle, which greatly increases the risk of electro-static damage to the pattern (ESD).

Hard-tip, soft-spring lithography.

PubMed

Shim, Wooyoung; Braunschweig, Adam B; Liao, Xing; Chai, Jinan; Lim, Jong Kuk; Zheng, Gengfeng; Mirkin, Chad A

2011-01-27

Nanofabrication strategies are becoming increasingly expensive and equipment-intensive, and consequently less accessible to researchers. As an alternative, scanning probe lithography has become a popular means of preparing nanoscale structures, in part owing to its relatively low cost and high resolution, and a registration accuracy that exceeds most existing technologies. However, increasing the throughput of cantilever-based scanning probe systems while maintaining their resolution and registration advantages has from the outset been a significant challenge. Even with impressive recent advances in cantilever array design, such arrays tend to be highly specialized for a given application, expensive, and often difficult to implement. It is therefore difficult to imagine commercially viable production methods based on scanning probe systems that rely on conventional cantilevers. Here we describe a low-cost and scalable cantilever-free tip-based nanopatterning method that uses an array of hard silicon tips mounted onto an elastomeric backing. This method-which we term hard-tip, soft-spring lithography-overcomes the throughput problems of cantilever-based scanning probe systems and the resolution limits imposed by the use of elastomeric stamps and tips: it is capable of delivering materials or energy to a surface to create arbitrary patterns of features with sub-50-nm resolution over centimetre-scale areas. We argue that hard-tip, soft-spring lithography is a versatile nanolithography strategy that should be widely adopted by academic and industrial researchers for rapid prototyping applications.

Evaluation of a fast and flexible OPC package: OPTISSIMO

NASA Astrophysics Data System (ADS)

Maurer, Wilhelm; Waas, Thomas; Eisenmann, Hans

1996-12-01

It is out of question, that current state-of-the-art lithography--printing 350 nm structures with i-line tools or 250 nm structures with DUV tools--needs to correct for proximity effects (OPC). Otherwise, all the well-known effects like line-end shortening, linewidth variation as a function of adjacent patterns, linewidth non-linearity, etc. will produce a pattern, that is significantly different from the intended design. In this paper, we report first evaluation results of OPTISSIMO, a software package for automatic proximity correction. Besides the ability to handle full-chip designs by preserving as much as possible of the original data-hierarchy, there are significant options for the user. A large number of choices can be made to balance between the precision of the correction and the complexity of the corrected design. The main target of our evaluations was to check for full-chip OPC for the gate level of a state-of-the-art design. This corresponds to print either linewidths in the 350 nm to 400 nm range with i-line lithography or 250 nm/300 nm linewidth with DUV lithography. Taking 400 nm i-line lithography as an example, 3% precision OPC which has been demonstrated. By using hierarchical data handling, it was shown, that even the data complexity of a 256 M DRAM can be managed within reasonable time.

New 3D structuring process for non-integrated circuit related technologies (Conference Presentation)

NASA Astrophysics Data System (ADS)

Nouri, Lamia; Possémé, Nicolas; Landis, Stéfan; Milesi, Frédéric; Gaillard, Frédéric-Xavier

2017-04-01

Fabrication processes that microelectronic developed for Integrated circuit (IC) technologies for decades, do not meet the new emerging structuration's requirements, in particular non-IC related technologies one, such as MEMS/NEMS, Micro-Fluidics, photovoltaics, lenses. Actually complex 3D structuration requires complex lithography patterning approaches such as gray-scale electron beam lithography, laser ablation, focused ion beam lithography, two photon polymerization. It is now challenging to find cheaper and easiest technique to achieve 3D structures. In this work, we propose a straightforward process to realize 3D structuration, intended for silicon based materials (Si, SiN, SiOCH). This structuration technique is based on nano-imprint lithography (NIL), ion implantation and selective wet etching. In a first step a pattern is performed by lithography on a substrate, then ion implantation is realized through a resist mask in order to create localized modifications in the material, thus the pattern is transferred into the subjacent layer. Finally, after the resist stripping, a selective wet etching is carried out to remove selectively the modified material regarding the non-modified one. In this paper, we will first present results achieved with simple 2D line array pattern processed either on Silicon or SiOCH samples. This step have been carried out to demonstrate the feasibility of this new structuration process. SEM pictures reveals that "infinite" selectivity between the implanted areas versus the non-implanted one could be achieved. We will show that a key combination between the type of implanted ion species and wet etching chemistries is required to obtain such results. The mechanisms understanding involved during both implantation and wet etching processes will also be presented through fine characterizations with Photoluminescence, Raman and Secondary Ion Mass Spectrometry (SIMS) for silicon samples, and ellipso-porosimetry and Fourier Transform InfraRed spectroscopy (FTIR) for SiOCH samples. Finally the benefit of this new patterning approach will be presented on 3D patterns structures.

Mask fabrication and its applications to extreme ultra-violet diffractive optics

NASA Astrophysics Data System (ADS)

Cheng, Yang-Chun

Short-wavelength radiation around 13nm of wavelength (Extreme Ultra-Violet, EUV) is being considered for patterning microcircuits, and other electronic chips with dimensions in the nanometer range. Interferometric Lithography (IL) uses two beams of radiation to form high-resolution interference fringes, as small as half the wavelength of the radiation used. As a preliminary step toward manufacturing technology, IL can be used to study the imaging properties of materials in a wide spectral range and at nanoscale dimensions. A simple implementation of IL uses two transmission diffraction gratings to form the interference pattern. More complex interference patterns can be created by using different types of transmission gratings. In this thesis, I describe the development of a EUV lithography system that uses diffractive optical elements (DOEs), from simple gratings to holographic structures. The exposure system is setup on a EUV undulator beamline at the Synchrotron Radiation Center, in the Center for NanoTechnology clean room. The setup of the EUV exposure system is relatively simple, while the design and fabrication of the DOE "mask" is complex, and relies on advanced nanofabrication techniques. The EUV interferometric lithography provides reliable EUV exposures of line/space patterns and is ideal for the development of EUV resist technology. In this thesis I explore the fabrication of these DOE for the EUV range, and discuss the processes I have developed for the fabrication of ultra-thin membranes. In addition, I discuss EUV holographic lithography and generalized Talbot imaging techniques to extend the capability of our EUV-IL system to pattern arbitrary shapes, using more coherent sources than the undulator. In a series of experiments, we have demonstrated the use of a soft X-ray (EUV) laser as effective source for EUV lithography. EUV-IL, as implemented at CNTech, is being used by several companies and research organizations to characterize photoresist materials.

Use of Sacrificial Nanoparticles to Remove the Effects of Shot-noise in Contact Holes Fabricated by E-beam Lithography.

PubMed

Rananavare, Shankar B; Morakinyo, Moshood K

2017-02-12

Nano-patterns fabricated with extreme ultraviolet (EUV) or electron-beam (E-beam) lithography exhibit unexpected variations in size. This variation has been attributed to statistical fluctuations in the number of photons/electrons arriving at a given nano-region arising from shot-noise (SN). The SN varies inversely to the square root of a number of photons/electrons. For a fixed dosage, the SN is larger in EUV and E-beam lithographies than for traditional (193 nm) optical lithography. Bottom-up and top-down patterning approaches are combined to minimize the effects of shot noise in nano-hole patterning. Specifically, an amino-silane surfactant self-assembles on a silicon wafer that is subsequently spin-coated with a 100 nm film of a PMMA-based E-beam photoresist. Exposure to the E-beam and the subsequent development uncover the underlying surfactant film at the bottoms of the holes. Dipping the wafer in a suspension of negatively charged, citrate-capped, 20 nm gold nanoparticles (GNP) deposits one particle per hole. The exposed positively charged surfactant film in the hole electrostatically funnels the negatively charged nanoparticle to the center of an exposed hole, which permanently fixes the positional registry. Next, by heating near the glass transition temperature of the photoresist polymer, the photoresist film reflows and engulfs the nanoparticles. This process erases the holes affected by SN but leaves the deposited GNPs locked in place by strong electrostatic binding. Treatment with oxygen plasma exposes the GNPs by etching a thin layer of the photoresist. Wet-etching the exposed GNPs with a solution of I2/KI yields uniform holes located at the center of indentations patterned by E-beam lithography. The experiments presented show that the approach reduces the variation in the size of the holes caused by SN from 35% to below 10%. The method extends the patterning limits of transistor contact holes to below 20 nm.

157-nm photomask handling and infrastructure: requirements and feasibility

NASA Astrophysics Data System (ADS)

Cullins, Jerry; Muzio, Edward G.

2001-09-01

Photomask handling is significantly more challenging for 157 nm lithography than for any previous generation of optical lithography. First, pellicle materials are not currently available which meet all the requirements for 157 nm lithography. Polymeric materials used at 193 nm higher wavelengths are not sufficiently transmissive at 157 nm, while modified fused silica materials have adequate transmission properties but introduce optical distortion. Second, the problem of molecular level contamination on the reticle must be solved. This contamination is due to the presence of oxygen, carbon dioxide, water, and other attenuators of 157 nm radiation on the mask surface. It must be removed using something other than the lithography laser due to throughput and cost of ownership considerations. Third, there is the issue of removing attenuators from under the pellicle after a material becomes available. Both the ambient atmosphere and other introduced contaminants must be removed from the space between the reticle and pellicle after cleaning but before exposure. Fourth are the potential issues for storage of reticles both during transportation from the mask shop and after it is in the wafer fab. Finally, the problems associated with operating in an optically inert dry environment must be addressed. The lack of moisture in the environment removes one of the key electrical discharge paths off of the reticle, which greatly increases the risk of electrostatic damage to the pattern (ESD). In order to address these and related issues in a timeframe consistent with the aggressive implementation plan for 157 nm lithography, International Sematech (ISMT) formed the 157 nm Reticle Handling Team in November of 1999. This paper details the most critical results to date of this industry-wide team, and gives a prognosis for successful completion of the team's primary goal: a demonstration of a feasible 157 nm reticle handling strategy by December of 2000.

Matching OPC and masks on 300-mm lithography tools utilizing variable illumination settings

NASA Astrophysics Data System (ADS)

Palitzsch, Katrin; Kubis, Michael; Schroeder, Uwe P.; Schumacher, Karl; Frangen, Andreas

2004-05-01

CD control is crucial to maximize product yields on 300mm wafers. This is particularly true for DRAM frontend lithography layers, like gate level, and deep trench (capacitor) level. In the DRAM process, large areas of the chip are taken up by array structures, which are difficult to structure due to aggressive pitch requirements. Consequently, the lithography process is centered such that the array structures are printed on target. Optical proximity correction is applied to print gate level structures in the periphery circuitry on target. Only slight differences of the different Zernike terms can cause rather large variations of the proximity curves, resulting in a difference of isolated and semi-isolated lines printed on different tools. If the deviations are too large, tool specific OPC is needed. The same is true for deep trench level, where the length to width ratio of elongated contact-like structures is an important parameter to adjust the electrical properties of the chip. Again, masks with specific biases for tools with different Zernikes are needed to optimize product yield. Additionally, mask making contributes to the CD variation of the process. Theoretically, the CD deviation caused by an off-centered mask process can easily eat up the majority of the CD budget of a lithography process. In practice, masks are very often distributed intelligently among production tools, such that lens and mask effects cancel each other. However, only dose adjusting and mask allocation may still result in a high CD variation with large systematical contributions. By adjusting the illumination settings, we have successfully implemented a method to reduce CD variation on our advanced processes. Especially inner and outer sigma for annular illumination, and the numerical aperture, can be optimized to match mask and stepper properties. This process will be shown to overcome slight lens and mask differences effectively. The effects on lithography process windows have to be considered, nonetheless.

Microenvironmental Stiffness of 3D Polymeric Structures to Study Invasive Rates of Cancer Cells.

PubMed

Lemma, Enrico Domenico; Spagnolo, Barbara; Rizzi, Francesco; Corvaglia, Stefania; Pisanello, Marco; De Vittorio, Massimo; Pisanello, Ferruccio

2017-11-01

Cells are highly dynamic elements, continuously interacting with the extracellular environment. Mechanical forces sensed and applied by cells are responsible for cellular adhesion, motility, and deformation, and are heavily involved in determining cancer spreading and metastasis formation. Cell/extracellular matrix interactions are commonly analyzed with the use of hydrogels and 3D microfabricated scaffolds. However, currently available techniques have a limited control over the stiffness of microscaffolds and do not allow for separating environmental properties from biological processes in driving cell mechanical behavior, including nuclear deformability and cell invasiveness. Herein, a new approach is presented to study tumor cell invasiveness by exploiting an innovative class of polymeric scaffolds based on two-photon lithography to control the stiffness of deterministic microenvironments in 3D. This is obtained by fine-tuning of the laser power during the lithography, thus locally modifying both structural and mechanical properties in the same fabrication process. Cage-like structures and cylindric stent-like microscaffolds are fabricated with different Young's modulus and stiffness gradients, allowing obtaining new insights on the mechanical interplay between tumor cells and the surrounding environments. In particular, cell invasion is mostly driven by softer architectures, and the introduction of 3D stiffness "weak spots" is shown to boost the rate at which cancer cells invade the scaffolds. The possibility to modulate structural compliance also allowed estimating the force distribution exerted by a single cell on the scaffold, revealing that both pushing and pulling forces are involved in the cell-structure interaction. Overall, exploiting this method to obtain a wide range of 3D architectures with locally engineered stiffness can pave the way for unique applications to study tumor cell dynamics. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Controlled evaporative self-assembly of confined microfluids: A route to complex ordered structures

NASA Astrophysics Data System (ADS)

Byun, Myunghwan

The evaporative self-assembly of nonvolatile solutes such as polymers, nanocrystals, and carbon nanotubes has been widely recognized as a non-lithographic means of producing a diverse range of intriguing complex structures. Due to the spatial variation of evaporative flux and possible convection, however, these non-equilibrium dissipative structures (e.g., fingering patterns and polygonal network structures) are often irregularly and stochastically organized. Yet for many applications in microelectronics, data storage devices, and biotechnology, it is highly desirable to achieve surface patterns having a well-controlled spatial arrangement. To date, only a few elegant studies have centered on precise control over the evaporation process to produce ordered structures. In a remarked comparison with conventional lithography techniques, surface patterning by controlled solvent evaporation is simple and cost-effective, offering a lithography- and external field-free means to organize nonvolatile materials into ordered microscopic structures over large surface areas. The ability to engineer an evaporative self-assembly process that yields a wide range of complex, self-organizing structures over large areas offers tremendous potential for applications in electronics, optoelectronics, and bio- or chemical sensors. We developed a facile, robust tool for evaporating polymer, nanoparticle, or DNA solutions in curve-on-flat geometries to create versatile, highly regular microstructures, including hierarchically structured polymer blend rings, conjugated polymer "snake-skins", block copolymer stripes, and punch-hole-like meshes, biomolecular microring arrays, etc. The mechanism of structure formation was elucidated both experimentally and theoretically. Our method further enhances current fabrication approaches to creating highly ordered structures in a simple and cost-effective manner, envisioning the potential to be tailored for use in photonics, optoelectronics, microfluidic devices, nanotechnology and biotechnology, etc.

Scaffold pore space modulation through intelligent design of dissolvable microparticles.

PubMed

Liebschner, Michael A K; Wettergreen, Matthew

2012-01-01

The goal of this area of research is to manipulate the pore space of scaffolds through the application of an intelligent design concept on dissolvable microparticles. To accomplish this goal, we developed an efficient and repeatable process for fabrication of microparticles from multiple materials using a combination of rapid prototyping (RP) and soft lithography. Phase changed 3D printing was used to create masters for PDMS molds. A photocrosslinkable polymer was then delivered into these molds to make geometrically complex 3D microparticles. This repeatable process has demonstrated to generate the objects with greater than 95% repeatability with complete pattern transfer. This process was illustrated for three different shapes of various complexities. The shapes were based on the extrusion of 2D shapes. This may allow simplification of the fabrication process in the future combined with a direct transfer of the findings. Altering the shapes of particles used for porous scaffold fabrication will allow for tailoring of the pore shapes, and therefore their biological function within a porous tissue engineering scaffold. Through permeation experiments, we have shown that the pore geometry may alter the permeability coefficient of scaffolds while influencing mechanical properties to a lesser extent. By selecting different porogen shapes, the nutrition transport and scaffold degradation can be significantly influenced with minimal effect on the mechanical integrity of the construct. In addition, the different shapes may allow a control of drug release by modifying their surface-to-volume ratio, which could modulate drug delivery over time. While soft lithography is currently used with photolithography, its high precision is offset by high cost of production. The employment of RP to a specific resolution offers a much less expensive alternative with increased throughput due to the speed of current RP systems.

Two-layer critical dimensions and overlay process window characterization and improvement in full-chip computational lithography

NASA Astrophysics Data System (ADS)

Sturtevant, John L.; Liubich, Vlad; Gupta, Rachit

2016-04-01

Edge placement error (EPE) was a term initially introduced to describe the difference between predicted pattern contour edge and the design target for a single design layer. Strictly speaking, this quantity is not directly measurable in the fab. What is of vital importance is the relative edge placement errors between different design layers, and in the era of multipatterning, the different constituent mask sublayers for a single design layer. The critical dimensions (CD) and overlay between two layers can be measured in the fab, and there has always been a strong emphasis on control of overlay between design layers. The progress in this realm has been remarkable, accelerated in part at least by the proliferation of multipatterning, which reduces the available overlay budget by introducing a coupling of overlay and CD errors for the target layer. Computational lithography makes possible the full-chip assessment of two-layer edge to edge distances and two-layer contact overlap area. We will investigate examples of via-metal model-based analysis of CD and overlay errors. We will investigate both single patterning and double patterning. For single patterning, we show the advantage of contour-to-contour simulation over contour to target simulation, and how the addition of aberrations in the optical models can provide a more realistic CD-overlay process window (PW) for edge placement errors. For double patterning, the interaction of 4-layer CD and overlay errors is very complex, but we illustrate that not only can full-chip verification identify potential two-layer hotspots, the optical proximity correction engine can act to mitigate such hotspots and enlarge the joint CD-overlay PW.

Practical tolerancing and performance implications for XUV projection lithography reduction systems (Poster Paper)

NASA Astrophysics Data System (ADS)

Viswanathan, Vriddhachalam K.

1992-07-01

Practical considerations that will strongly affect the imaging capabilities of reflecting systems for extreme-ultraviolet (XUV) projection lithography include manufacturing tolerances and thermal distortion of the mirror surfaces due to absorption of a fraction of the incident radiation beam. We have analyzed the potential magnitudes of these effects for two types of reflective projection optical designs. We find that concentric, symmetric two-mirror systems are less sensitive to manufacturing errors and thermal distortion than off-axis, four-mirror systems.

Tunable Far Infrared Semiconductor Sources.

DTIC Science & Technology

1984-01-01

plasmons in Si-MOS4 hot electron transport in Si-MOS-devices a , ABSTR ACT (Coathwe st e verse 8641 It ut’.weemY dmd ideti ty by block tnmber) {fhe...After baking at 900C for 20 minutes the photoresist was -17- exposed for 8 seconds on the SUss-MJB3-contact lithography machine. To obtain grating...could fabricate Al gratings with 1.5 am - periods on Si-MOSFETs and GaAs-samples by optical contact lithography and lift-off metallization. Fig. 8 shows

Low-cost method for producing extreme ultraviolet lithography optics

DOEpatents

Folta, James A [Livermore, CA; Montcalm, Claude [Fort Collins, CO; Taylor, John S [Livermore, CA; Spiller, Eberhard A [Mt. Kisco, NY

2003-11-21

Spherical and non-spherical optical elements produced by standard optical figuring and polishing techniques are extremely expensive. Such surfaces can be cheaply produced by diamond turning; however, the roughness in the diamond turned surface prevent their use for EUV lithography. These ripples are smoothed with a coating of polyimide before applying a 60 period Mo/Si multilayer to reflect a wavelength of 134 .ANG. and have obtained peak reflectivities close to 63%. The savings in cost are about a factor of 100.

Using a neural network to proximity correct patterns written with a Cambridge electron beam microfabricator 10.5 lithography system

NASA Astrophysics Data System (ADS)

Cummings, K. D.; Frye, R. C.; Rietman, E. A.

1990-10-01

This letter describes the initial results of using a theoretical determination of the proximity function and an adaptively trained neural network to proximity-correct patterns written on a Cambridge electron beam lithography system. The methods described are complete and may be applied to any electron beam exposure system that can modify the dose during exposure. The patterns produced in resist show the effects of proximity correction versus noncorrected patterns.

OSA Proceedings of the Topical Meeting on Soft-X-Ray Projection Lithography Held in Monterey, California on 10-12 April 1991. Volume 12

DTIC Science & Technology

1992-05-22

Carbide because of its high thermal the mirror on its backside or edge. Shott Zerodur conductivity. Edge cooling causes a larger exceeded the limit by about...Characterization Angstrom-level noncontact profiling of mirrors for soft x-ray lithography............ 134 Paul Glenn Nonspecular Scattering from X-Ray...structed by patterning a Mo/Si Tropel Division of GCA Corporation. multilayer coated silicon wafer. The mirrors were coated at AT&T Bell The multilayer

NbN superconducting nanonetwork fabricated using porous silicon templates and high-resolution electron beam lithography

NASA Astrophysics Data System (ADS)

Salvato, M.; Baghdadi, R.; Cirillo, C.; Prischepa, S. L.; Dolgiy, A. L.; Bondarenko, V. P.; Lombardi, F.; Attanasio, C.

2017-11-01

Superconducting NbN nanonetworks with a very small number of interconnected nanowires, with diameter of the order of 4 nm, are fabricated combining a bottom-up (use of porous silicon nanotemplates) with a top-down technique (high-resolution electron beam lithography). The method is easy to control and allows the fabrication of devices, on a robust support, with electrical properties close to a one-dimensional superconductor that can be used fruitfully for novel applications.

SOI layout decomposition for double patterning lithography on high-performance computer platforms

NASA Astrophysics Data System (ADS)

Verstov, Vladimir; Zinchenko, Lyudmila; Makarchuk, Vladimir

2014-12-01

In the paper silicon on insulator layout decomposition algorithms for the double patterning lithography on high performance computing platforms are discussed. Our approach is based on the use of a contradiction graph and a modified concurrent breadth-first search algorithm. We evaluate our technique on 45 nm Nangate Open Cell Library including non-Manhattan geometry. Experimental results show that our soft computing algorithms decompose layout successfully and a minimal distance between polygons in layout is increased.

On-wire lithography-generated molecule-based transport junctions: a new testbed for molecular electronics.

PubMed

Chen, Xiaodong; Jeon, You-Moon; Jang, Jae-Won; Qin, Lidong; Huo, Fengwei; Wei, Wei; Mirkin, Chad A

2008-07-02

On-wire lithography (OWL) fabricated nanogaps are used as a new testbed to construct molecular transport junctions (MTJs) through the assembly of thiolated molecular wires across a nanogap formed between two Au electrodes. In addition, we show that one can use OWL to rapidly characterize a MTJ and optimize gap size for two molecular wires of different dimensions. Finally, we have used this new testbed to identify unusual temperature-dependent transport mechanisms for alpha,omega-dithiol terminated oligo(phenylene ethynylene).

Free-standing bimetallic nanorings and nanoring arrays made by on-wire lithography.

PubMed

Liusman, Cipto; Li, Shuzhou; Chen, Xiaodong; Wei, Wei; Zhang, Hua; Schatz, George C; Boey, Freddy; Mirkin, Chad A

2010-12-28

This paper describes a new strategy for synthesizing free-standing bimetallic nanorings and nanoring arrays based upon on-wire lithography and a galvanic replacement reaction. The strategy allows one to tune the diameter, length, and therefore aspect ratio of the nanorings. In addition, it can be used to produce arrays of nanorings in high yield with control over number and spacing. Spectroscopic studies and discrete dipole approximation calculations show that nanoring dimers exhibit greater surface enhanced Raman scattering than the analogous nanodisk dimers.

Solution Exchange Lithography: A Versatile Tool for Sequential Surface Engineering

NASA Astrophysics Data System (ADS)

Pester, Christian; Mattson, Kaila; Bothman, David; Klinger, Daniel; Lee, Kenneth; Discekici, Emre; Narupai, Benjaporn; Hawker, Craig

The covalent attachment of polymers has emerged as a viable strategy for the preparation of multi-functional surfaces. Patterned, surface-grafted polymer brushes provide spatial control over wetting, mechanical, biological or electronic properties, and allow fabrication of `intelligent' substrates which selectively adapt to their environment. However, the route towards patterned polymer brush surfaces often remains challenging, creating a demand for more efficient and less complicated fabrication strategies. We describe the design and application of a novel experimental setup to combine light-mediated and flow chemistry for the fabrication of hierarchical surface-grafted polymer brushes. Using light-mediated, surface initiated controlled radical polymerization and post-functionalization via well-established, and highly efficient chemistries, polymer brush films of previously unimaginable complexity are now shown to be accessible. This methodology allows full flexibility to exchange both lithographic photomasks and chemical environments in-situ, readily affording multidimensional thin film architectures, all from uniformly functionalized substrates.

International Conference on Integrated Optical Circuit Engineering, 1st, Cambridge, MA, October 23-25, 1984, Proceedings

NASA Astrophysics Data System (ADS)

Ostrowsky, D. B.; Sriram, S.

Aspects of waveguide technology are explored, taking into account waveguide fabrication techniques in GaAs/GaAlAs, the design and fabrication of AlGaAs/GaAs phase couplers for optical integrated circuit applications, ion implanted GaAs integrated optics fabrication technology, a direct writing electron beam lithography based process for the realization of optoelectronic integrated circuits, and advances in the development of semiconductor integrated optical circuits for telecommunications. Other subjects examined are related to optical signal processing, optical switching, and questions of optical bistability and logic. Attention is given to acousto-optic techniques in integrated optics, acousto-optic Bragg diffraction in proton exchanged waveguides, optical threshold logic architectures for hybrid binary/residue processors, integrated optical modulation and switching, all-optic logic devices for waveguide optics, optoelectronic switching, high-speed photodetector switching, and a mechanical optical switch.

Intensity tunable infrared broadband absorbers based on VO2 phase transition using planar layered thin films

PubMed Central

Kocer, Hasan; Butun, Serkan; Palacios, Edgar; Liu, Zizhuo; Tongay, Sefaattin; Fu, Deyi; Wang, Kevin; Wu, Junqiao; Aydin, Koray

2015-01-01

Plasmonic and metamaterial based nano/micro-structured materials enable spectrally selective resonant absorption, where the resonant bandwidth and absorption intensity can be engineered by controlling the size and geometry of nanostructures. Here, we demonstrate a simple, lithography-free approach for obtaining a resonant and dynamically tunable broadband absorber based on vanadium dioxide (VO2) phase transition. Using planar layered thin film structures, where top layer is chosen to be an ultrathin (20 nm) VO2 film, we demonstrate broadband IR light absorption tuning (from ~90% to ~30% in measured absorption) over the entire mid-wavelength infrared spectrum. Our numerical and experimental results indicate that the bandwidth of the absorption bands can be controlled by changing the dielectric spacer layer thickness. Broadband tunable absorbers can find applications in absorption filters, thermal emitters, thermophotovoltaics and sensing. PMID:26294085

Steering and filtering white light with resonant waveguide gratings

NASA Astrophysics Data System (ADS)

Quaranta, Giorgio; Basset, Guillaume; Martin, Olivier J. F.; Gallinet, Benjamin

2017-08-01

A novel thin-film single-layer structure based on resonant waveguide gratings (RWGs) allows to engineer selective color filtering and steering of white light. The unit cell of the structure consists of two adjacent finite-length and cross-talking RWGs, where the former acts as in-coupler and the latter acts as out-coupler. The structure is made by only one nano-imprint lithography replication and one thin film layer deposition, making it fully compatible with up-scalable fabrication processes. We characterize a fabricated optical security element designed to work with the flash and the camera of a smartphone in off-axis light steering configuration, where the pattern is revealed only by placing the smartphone in the proper position. Widespread applications are foreseen in a variety of fields, such as multifocal or monochromatic lenses, solar cells, biosensors, security devices and seethrough optical combiners for near-eye displays.

Micro/nano-fabrication technologies for cell biology.

PubMed

Qian, Tongcheng; Wang, Yingxiao

2010-10-01

Micro/nano-fabrication techniques, such as soft lithography and electrospinning, have been well-developed and widely applied in many research fields in the past decade. Due to the low costs and simple procedures, these techniques have become important and popular for biological studies. In this review, we focus on the studies integrating micro/nano-fabrication work to elucidate the molecular mechanism of signaling transduction in cell biology. We first describe different micro/nano-fabrication technologies, including techniques generating three-dimensional scaffolds for tissue engineering. We then introduce the application of these technologies in manipulating the physical or chemical micro/nano-environment to regulate the cellular behavior and response, such as cell life and death, differentiation, proliferation, and cell migration. Recent advancement in integrating the micro/nano-technologies and live cell imaging are also discussed. Finally, potential schemes in cell biology involving micro/nano-fabrication technologies are proposed to provide perspectives on the future research activities.

Micro/nano-fabrication technologies for cell biology

PubMed Central

Qian, Tongcheng

2012-01-01

Micro/nano-fabrication techniques, such as soft lithography and electrospinning, have been well-developed and widely applied in many research fields in the past decade. Due to the low costs and simple procedures, these techniques have become important and popular for biological studies. In this review, we focus on the studies integrating micro/nano-fabrication work to elucidate the molecular mechanism of signaling transduction in cell biology. We first describe different micro/nano-fabrication technologies, including techniques generating three-dimensional scaffolds for tissue engineering. We then introduce the application of these technologies in manipulating the physical or chemical micro/nano-environment to regulate the cellular behavior and response, such as cell life and death, differentiation, proliferation, and cell migration. Recent advancement in integrating the micro/nano-technologies and live cell imaging are also discussed. Finally, potential schemes in cell biology involving micro/nano-fabrication technologies are proposed to provide perspectives on the future research activities. PMID:20490938

Commensurability and stability in nonperiodic systems

PubMed Central

Fasano, Y.; De Seta, M.; Menghini, M.; Pastoriza, H.; de la Cruz, F.

2005-01-01

We have investigated the response of 3D Bi2Sr2CaCu2O8 vortex structures to a weak perturbation induced by 2D Fe pinning structures acting on one extremity of vortex lines. The pinning patterns were nano-engineered at the sample surface by means of either a Bitter decoration of the vortex lattice or electron-beam lithography. The commensurability conditions between 2D rigid pinning potentials and 3D elastic structures with short-range positional and long-range orientational correlation have been experimentally determined. When the 2D potential is a replica of the nonperiodic vortex structure an amplification of its interaction with the vortex structure takes place. This effect is detected only for the first matching field, becoming negligible for other matching fields. On the other hand, a periodic 2D perturbation is shown to transform the nonperiodic Bragg glass-like structure into an Abrikosov crystal with an effective Debye–Waller factor. PMID:16576763