WorldWideScience

Sample records for repeated lithography processes

  1. Process Control for Nanoimprint Lithography

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    To tackle the demoulding and conglutinating problem with the resist and hard mold in the nanoimprint lithography process, a soft mould can be used to demould and reduce the macro or micro mismatch between mould bottom surface and wafer top surface. In nanoimprint lithography process, a mathematical equation is formulated to demonstrate the relation between the residual resist thickness and the pressing force during pressing the mould toward the resist-coated wafer.Based on these analytical studies, a new imprint process, which includes a pre-cure release of the pressing force, was proposed for the high-conformity transfer of nano-patterns from the mould to the wafer. The results of a series of imprint experiments showed that the proposed loading process could meet the requirements for the imprint of different patterns and feature sizes while maintaining a uniform residual resist and non-distorted transfer of nano-patterns from the mould to the resistcoated wafer.

  2. Lithography

    CERN Document Server

    Landis, Stefan

    2013-01-01

    Lithography is now a complex tool at the heart of a technological process for manufacturing micro and nanocomponents. A multidisciplinary technology, lithography continues to push the limits of optics, chemistry, mechanics, micro and nano-fluids, etc. This book deals with essential technologies and processes, primarily used in industrial manufacturing of microprocessors and other electronic components.

  3. Multi-Repeated Projection Lithography for High-Precision Linear Scale Based on Average Homogenization Effect

    Directory of Open Access Journals (Sweden)

    Dongxu Ren

    2016-04-01

    Full Text Available A multi-repeated photolithography method for manufacturing an incremental linear scale using projection lithography is presented. The method is based on the average homogenization effect that periodically superposes the light intensity of different locations of pitches in the mask to make a consistent energy distribution at a specific wavelength, from which the accuracy of a linear scale can be improved precisely using the average pitch with different step distances. The method’s theoretical error is within 0.01 µm for a periodic mask with a 2-µm sine-wave error. The intensity error models in the focal plane include the rectangular grating error on the mask, static positioning error, and lithography lens focal plane alignment error, which affect pitch uniformity less than in the common linear scale projection lithography splicing process. It was analyzed and confirmed that increasing the repeat exposure number of a single stripe could improve accuracy, as could adjusting the exposure spacing to achieve a set proportion of black and white stripes. According to the experimental results, the effectiveness of the multi-repeated photolithography method is confirmed to easily realize a pitch accuracy of 43 nm in any 10 locations of 1 m, and the whole length accuracy of the linear scale is less than 1 µm/m.

  4. Multi-Repeated Projection Lithography for High-Precision Linear Scale Based on Average Homogenization Effect.

    Science.gov (United States)

    Ren, Dongxu; Zhao, Huiying; Zhang, Chupeng; Yuan, Daocheng; Xi, Jianpu; Zhu, Xueliang; Ban, Xinxing; Dong, Longchao; Gu, Yawen; Jiang, Chunye

    2016-04-14

    A multi-repeated photolithography method for manufacturing an incremental linear scale using projection lithography is presented. The method is based on the average homogenization effect that periodically superposes the light intensity of different locations of pitches in the mask to make a consistent energy distribution at a specific wavelength, from which the accuracy of a linear scale can be improved precisely using the average pitch with different step distances. The method's theoretical error is within 0.01 µm for a periodic mask with a 2-µm sine-wave error. The intensity error models in the focal plane include the rectangular grating error on the mask, static positioning error, and lithography lens focal plane alignment error, which affect pitch uniformity less than in the common linear scale projection lithography splicing process. It was analyzed and confirmed that increasing the repeat exposure number of a single stripe could improve accuracy, as could adjusting the exposure spacing to achieve a set proportion of black and white stripes. According to the experimental results, the effectiveness of the multi-repeated photolithography method is confirmed to easily realize a pitch accuracy of 43 nm in any 10 locations of 1 m, and the whole length accuracy of the linear scale is less than 1 µm/m.

  5. Nanoimprint lithography an enabling process for nanofabrication

    CERN Document Server

    Zhou, Weimin

    2013-01-01

    Nanoimprint Lithography: An enabling process for nanofabrication presents a comprehensive description of nanotechnology that is one of the most promising low-cost, high-throughput technologies for manufacturing nanostructures, and an emerging lithography candidates for 22, 16 and 11 nm nodes. It provides the exciting, multidisciplinary field, offering a wide range of topics covering: principles, process, material and application. This book would be of specific interest for researchers and graduate students in the field of nanoscience, nanotechnology and nanofabrication, material, physical, chemical, electric engineering and biology. Dr. Weimin Zhou is an associate professor at Shanghai Nanotechnology Promotion Center, China.

  6. Advanced processes for 193-nm immersion lithography

    CERN Document Server

    Wei, Yayi

    2009-01-01

    This book is a comprehensive guide to advanced processes and materials used in 193-nm immersion lithography (193i). It is an important text for those new to the field as well as for current practitioners who want to broaden their understanding of this latest technology. The book can be used as course material for graduate students of electrical engineering, material sciences, physics, chemistry, and microelectronics engineering and can also be used to train engineers involved in the manufacture of integrated circuits. It provides techniques for selecting critical materials (topcoats, photoresi

  7. Step-and-Repeat Nanoimprint-, Photo- and Laser Lithography from One Customised CNC Machine.

    Science.gov (United States)

    Greer, Andrew Im; Della-Rosa, Benoit; Khokhar, Ali Z; Gadegaard, Nikolaj

    2016-12-01

    The conversion of a computer numerical control machine into a nanoimprint step-and-repeat tool with additional laser- and photolithography capacity is documented here. All three processes, each demonstrated on a variety of photoresists, are performed successfully and analysed so as to enable the reader to relate their known lithography process(es) to the findings. Using the converted tool, 1 cm(2) of nanopattern may be exposed in 6 s, over 3300 times faster than the electron beam equivalent. Nanoimprint tools are commercially available, but these can cost around 1000 times more than this customised computer numerical control (CNC) machine. The converted equipment facilitates rapid production and large area micro- and nanoscale research on small grants, ultimately enabling faster and more diverse growth in this field of science. In comparison to commercial tools, this converted CNC also boasts capacity to handle larger substrates, temperature control and active force control, up to ten times more curing dose and compactness. Actual devices are fabricated using the machine including an expanded nanotopographic array and microfluidic PDMS Y-channel mixers.

  8. Step-and-Repeat Nanoimprint-, Photo- and Laser Lithography from One Customised CNC Machine

    Science.gov (United States)

    Greer, Andrew IM; Della-Rosa, Benoit; Khokhar, Ali Z.; Gadegaard, Nikolaj

    2016-03-01

    The conversion of a computer numerical control machine into a nanoimprint step-and-repeat tool with additional laser- and photolithography capacity is documented here. All three processes, each demonstrated on a variety of photoresists, are performed successfully and analysed so as to enable the reader to relate their known lithography process(es) to the findings. Using the converted tool, 1 cm2 of nanopattern may be exposed in 6 s, over 3300 times faster than the electron beam equivalent. Nanoimprint tools are commercially available, but these can cost around 1000 times more than this customised computer numerical control (CNC) machine. The converted equipment facilitates rapid production and large area micro- and nanoscale research on small grants, ultimately enabling faster and more diverse growth in this field of science. In comparison to commercial tools, this converted CNC also boasts capacity to handle larger substrates, temperature control and active force control, up to ten times more curing dose and compactness. Actual devices are fabricated using the machine including an expanded nanotopographic array and microfluidic PDMS Y-channel mixers.

  9. Thickness optimization for lithography process on silicon substrate

    Science.gov (United States)

    Su, Xiaojing; Su, Yajuan; Liu, Yansong; Chen, Fong; Liu, Zhimin; Zhang, Wei; Li, Bifeng; Gao, Tao; Wei, Yayi

    2015-03-01

    With the development of the lithography, the demand for critical dimension (CD) and CD uniformity (CDU) has reached a new level, which is harder and harder to achieve. There exists reflection at the interface between photo-resist and substrate during lithography exposure. This reflection has negative impact on CD and CDU control. It is possible to optimize the litho stack and film stack thickness on different lithography conditions. With the optimized stack, the total reflectivity for all incident angles at the interface can be controlled less than 0.5%, ideally 0.1%, which enhances process window (PW) most of the time. The theoretical results are verified by the experiment results from foundry, which helps the foundry achieve the mass production finally.

  10. Process window study with various illuminations for EUV lithography applications

    Science.gov (United States)

    Lee, Sang Hun; Zhang, Zhiyu

    2007-03-01

    EUV lithography has the ability to support 22 nm logic manufacturing and beyond. Similar to the DUV lithographic systems, partial coherence on EUV lithographic systems can have a big impact on process latitude for critical layers. Thus, it is important to understand the effect of partial coherence on EUV imaging systems. In this paper, process windows with various illumination settings are investigated. The experiments are conducted using the MET station at the Advance Light Source (ALS). In addition to the annular and dipole illuminations which reported in our last paper1, C-quad and Quad illuminations are used to explore the impact of the partial coherence on the process window. Even though the MET system has resolutions below 30nm dense lines, the exposures are targeted for 60nm, 50nm, and 45nm dense features due to the resist limitation. The experimental results are compared with simulation results using Intel's lithography modeling tool, I-Photo. Resist and aerial image threshold models are used for the comparison study. The experimental results correlate well with the resist based simulation results, but some discrepancies are observed for the aerial image threshold cases. We believe the discrepancies are due to the resist limitations. We found that the dipole shows the largest Depth of Focus for dense lines and spaces.

  11. Modelling the deformation process of flexible stamps for nanoimprint lithography

    DEFF Research Database (Denmark)

    Sonne, Mads Rostgaard

    The present thesis is devoted to numerical modelling of the deformation process of flexible stamps for nanoimprint lithography (NIL). The purpose of those models is to be able to predict the deformation and stretch of the flexixble stamps in order to take that into account when designing the plan...... 2D silicon master used in the NIL process. Two different manufacturing processes are investigated; (i) Embossing of an electroplated nickel foil into a hydrogen silsesquioxane (HSQ) polymer resist on a double-curved surface, (ii) NIL of a flexible polytetrafluoroethylene (PTFE) stamps...... into a polymethyl methacrylate (PMMA) resist. Challenges comprise several non-linear phenomena. First of all geometrical non-linearities arising from the inherent large strains and deformations during the process are modelled. Then, the constitutive behaviors of the nickel foil and the PTFE polymer during...... deformation are addressed. This is achieved by a general elasto-plastic description for the nickel foil and a viscoelastic-viscoplastic model for the PTFE material, in which the material parameters are found. Last, the contact conditions between the deforming stamp and the injection moulding tool insert...

  12. Nanoimprint lithography for nanodevice fabrication

    Science.gov (United States)

    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.

  13. Nanoimprint lithography for nanodevice fabrication.

    Science.gov (United States)

    Barcelo, Steven; Li, Zhiyong

    2016-01-01

    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.

  14. Hysteresis of magnetostructural transitions: Repeatable and non-repeatable processes

    Energy Technology Data Exchange (ETDEWEB)

    Provenzano, Virgil [National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Della Torre, Edward; Bennett, Lawrence H. [Department of Electrical and Computer Engineering, The George Washington University, Washington, DC 20052 (United States); ElBidweihy, Hatem, E-mail: Hatem@gwmail.gwu.edu [Department of Electrical and Computer Engineering, The George Washington University, Washington, DC 20052 (United States)

    2014-02-15

    The Gd{sub 5}Ge{sub 2}Si{sub 2} alloy and the off-stoichiometric Ni{sub 50}Mn{sub 35}In{sub 15} Heusler alloy belong to a special class of metallic materials that exhibit first-order magnetostructural transitions near room temperature. The magnetic properties of this class of materials have been extensively studied due to their interesting magnetic behavior and their potential for a number of technological applications such as refrigerants for near-room-temperature magnetic refrigeration. The thermally driven first-order transitions in these materials can be field-induced in the reverse order by applying a strong enough field. The field-induced transitions are typically accompanied by the presence of large magnetic hysteresis, the characteristics of which are a complicated function of temperature, field, and magneto-thermal history. In this study we show that the virgin curve, the major loop, and sequentially measured MH loops are the results of both repeatable and non-repeatable processes, in which the starting magnetostructural state, prior to the cycling of field, plays a major role. Using the Gd{sub 5}Ge{sub 2}Si{sub 2} and Ni{sub 50}Mn{sub 35}In{sub 15} alloys, as model materials, we show that a starting single phase state results in fully repeatable processes and large magnetic hysteresis, whereas a mixed phase starting state results in non-repeatable processes and smaller hysteresis.

  15. Chemical trimming overcoat: an enhancing composition and process for 193nm lithography

    Science.gov (United States)

    Liu, Cong; Rowell, Kevin; Joesten, Lori; Baranowski, Paul; Kaur, Irvinder; Huang, Wanyi; Leonard, JoAnne; Jeong, Hae-Mi; Im, Kwang-Hwyi; Estelle, Tom; Cutler, Charlotte; Pohlers, Gerd; Yin, Wenyan; Fallon, Patricia; Li, Mingqi; Jeon, Hyun; Xu, Cheng Bai; Trefonas, Pete

    2016-03-01

    As the critical dimension of devices is approaching the resolution limit of 193nm photo lithography, multiple patterning processes have been developed to print smaller CD and pitch. Multiple patterning and other advanced lithographic processes often require the formation of isolated features such as lines or posts by direct lithographic printing. The formation of isolated features with an acceptable process window, however, can pose a challenge as a result of poor aerial image contrast at defocus. Herein we report a novel Chemical Trimming Overcoat (CTO) as an extra step after lithography that allows us to achieve smaller feature size and better process window.

  16. Resist and Exposure Processes for Sub-10-nm Electron and Ion Beam Lithography

    NARCIS (Netherlands)

    Sidorkin, V.A.

    2010-01-01

    The research work described in this thesis deals with studying the ultimate resolution capabilities of electron and ion beam lithography (EBL and IBL respectively) with a focus on resist and exposure processes. The aim of this research was to enlarge knowledge and improve methods on the formation of

  17. Resist and Exposure Processes for Sub-10-nm Electron and Ion Beam Lithography

    NARCIS (Netherlands)

    Sidorkin, V.A.

    2010-01-01

    The research work described in this thesis deals with studying the ultimate resolution capabilities of electron and ion beam lithography (EBL and IBL respectively) with a focus on resist and exposure processes. The aim of this research was to enlarge knowledge and improve methods on the formation of

  18. Soft-X-Ray Projection Lithography Using a High-Repetition-Rate Laser-Induced X-Ray Source for Sub-100 Nanometer Lithography Processes

    NARCIS (Netherlands)

    E. Louis,; F. Bijkerk,; Shmaenok, L.; Voorma, H. J.; van der Wiel, M. J.; Schlatmann, R.; Verhoeven, J.; van der Drift, E. W. J. M.; Romijn, J.; Rousseeuw, B. A. C.; Voss, F.; Desor, R.; Nikolaus, B.

    1993-01-01

    In this paper we present the status of a joint development programme on soft x-ray projection lithography (SXPL) integrating work on high brightness laser plasma sources. fabrication of multilayer x-ray mirrors. and patterning of reflection masks. We are in the process of optimization of a laser-pla

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

    Science.gov (United States)

    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, (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.

  20. Implementation and benefits of advanced process control for lithography CD and overlay

    Science.gov (United States)

    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.

  1. Biocompatibility of hydroxyapatite scaffolds processed by lithography-based additive manufacturing.

    Science.gov (United States)

    Tesavibul, Passakorn; Chantaweroad, Surapol; Laohaprapanon, Apinya; Channasanon, Somruethai; Uppanan, Paweena; Tanodekaew, Siriporn; Chalermkarnnon, Prasert; Sitthiseripratip, Kriskrai

    2015-01-01

    The fabrication of hydroxyapatite scaffolds for bone tissue engineering applications by using lithography-based additive manufacturing techniques has been introduced due to the abilities to control porous structures with suitable resolutions. In this research, the use of hydroxyapatite cellular structures, which are processed by lithography-based additive manufacturing machine, as a bone tissue engineering scaffold was investigated. The utilization of digital light processing system for additive manufacturing machine in laboratory scale was performed in order to fabricate the hydroxyapatite scaffold, of which biocompatibilities were eventually evaluated by direct contact and cell-culturing tests. In addition, the density and compressive strength of the scaffolds were also characterized. The results show that the hydroxyapatite scaffold at 77% of porosity with 91% of theoretical density and 0.36 MPa of the compressive strength are able to be processed. In comparison with a conventionally sintered hydroxyapatite, the scaffold did not present any cytotoxic signs while the viability of cells at 95.1% was reported. After 14 days of cell-culturing tests, the scaffold was able to be attached by pre-osteoblasts (MC3T3-E1) leading to cell proliferation and differentiation. The hydroxyapatite scaffold for bone tissue engineering was able to be processed by the lithography-based additive manufacturing machine while the biocompatibilities were also confirmed.

  2. Processing of Graphene combining Optical Detection and Scanning Probe Lithography

    Directory of Open Access Journals (Sweden)

    Zimmermann Sören

    2015-01-01

    Full Text Available This paper presents an experimental setup tailored for robotic processing of graphene with in-situ vision based control. A robust graphene detection approach is presented applying multiple image processing operations of the visual feedback provided by a high-resolution light microscope. Detected graphene flakes can be modified using a scanning probe based lithographical process that is directly linked to the in-situ optical images. The results of this process are discussed with respect to further application scenarios.

  3. High-power laser interference lithography process on photoresist: Effect of laser fluence and polarisation

    Energy Technology Data Exchange (ETDEWEB)

    Ellman, M. [CEIT and Tecnun (University of Navarra), Manuel de Lardizabal 15, 20018, San Sebastian (Spain)], E-mail: mellman@ceit.es; Rodriguez, A.; Perez, N.; Echeverria, M. [CEIT and Tecnun (University of Navarra), Manuel de Lardizabal 15, 20018, San Sebastian (Spain); Verevkin, Y.K. [Institute of Applied Physics, 46 Ul' yanova Street, 603600 Nizhny Novgorod (Russian Federation); Peng, C.S. [ORC (Tampere University of Technology), Korkeakoulunkatu 3, 33720 Tampere (Finland); Berthou, T. [SILIOS Technologies SA, Rue Gaston Imbert prolongee 13790 Peynier (France); Wang, Z. [MEC (Cardiff University), Queen' s Buildings, The Parade, Newport Road, Cardiff CF24 3AA (United Kingdom); Olaizola, S.M.; Ayerdi, I. [CEIT and Tecnun (University of Navarra), Manuel de Lardizabal 15, 20018, San Sebastian (Spain)

    2009-03-01

    High throughput and low cost fabrication techniques in the sub-micrometer scale are attractive for the industry. Laser interference lithography (LIL) is a promising technique that can produce one, two and three-dimensional periodical patterns over large areas. In this work, two- and four-beam laser interference lithography systems are implemented to produce respectively one- and two-dimensional periodical patterns. A high-power single pulse of {approx}8 ns is used as exposure process. The optimum exposure dose for a good feature patterning in a 600 nm layer of AZ-1505 photoresist deposited on silicon wafers is studied. The best aspect ratio is found for a laser fluence of 20 mJ/cm{sup 2}. A method to control the width of the sub-micrometer structures based on controlling the resist thickness and the laser fluence is proposed.

  4. Lithography process for patterning HgI2 photonic devices

    Science.gov (United States)

    Mescher, Mark J.; James, Ralph B.; Hermon, Haim

    2004-11-23

    A photolithographic process forms patterns on HgI.sub.2 surfaces and defines metal sublimation masks and electrodes to substantially improve device performance by increasing the realizable design space. Techniques for smoothing HgI.sub.2 surfaces and for producing trenches in HgI.sub.2 are provided. A sublimation process is described which produces etched-trench devices with enhanced electron-transport-only behavior.

  5. Reduction of postdevelop defects and process times for DUV lithography

    Science.gov (United States)

    Krishna, Murthy S.; Gurer, Emir; Lee, Ed C.; Flores, Gary E.; Ooka, Sandra S.; Salois, John W.; Cherry, Royal; Reynolds, Reese M.

    1999-06-01

    As the semiconductor industry moves into deeper sub-quarter micro regime, minimization of post develop process defects is of paramount significance in manufacturing environments. Reduce defects levels can significantly increase the yield in production, resulting in substantial cost savings and also reduce time to market of new devices. Typical approaches to reduce defect levels include extension of the DI rinse time immediately after completion of photoresists development, use of multiple rinse steps and variable rinse spin speed. However, many of these penalize the process throughput. The uniqueness of this project was the use of enhanced rinse hardware with a mechanistic understanding and characterization of defect generation for an advanced DUV resist.

  6. New processes associated with electron-beam lithography for ultra-small resonators

    Science.gov (United States)

    Tobing, Landobasa Y. M.; Zhang, Dao Hua

    2017-03-01

    High density ultrahigh resolution patterning with desired shape and size is a crucial requirement in nanotechnology and its applications. Electron beam lithography (EBL) is the most widely used lithography tool for these applications. However, achieving cost-effective patterning with sub-10-nm critical dimension has been challenging due to the inherent tradeoff between resolution and throughput. In this paper, we present cost-effective new processes associated with EBL technique, which include optimized resist selection and processing as well as sonicated cold development process. Using this process, we demonstrate sub-10-nm diameter metal dots at a pitch of 34 nm and sub-15 nm wide metal lines. Based on the same processes, we demonstrate the fabrication of u-shaped split ring resonator array of different metals with smallest fabricated resonator with 60 nm size and v-shape SRRs with the smallest gap spacing of 30 nm. By adjusting the SRR gap spacing through its arm length and opening angle, we have successfully demonstrated magnetic and electric resonances across the visible and ultraviolet range.

  7. Novel deep—submicron x—ray lithography process for T—shaped gate patterns

    Institute of Scientific and Technical Information of China (English)

    XieChangqing; YiFuting; 等

    2001-01-01

    The growing interest in the use of Gallium Arsenids semiconductor materials has presented many opportunities for device operational speed improvements but has also presented many problems for the device maker,A novel deep-submicron x-ray lithography process for T-shaped gate patterns useful for high-electron-mobility transistors(HEMT) is introduced in this work.In the fabrication of T-shaped gate a therr layer resists method is used.The x-ray exposure experiments were finished by Beijing Synchrotron Radiation Facility(BSRF) 3B1A beamline,and good result has been obtained.

  8. Advanced in-situ electron-beam lithography for deterministic nanophotonic device processing

    Energy Technology Data Exchange (ETDEWEB)

    Kaganskiy, Arsenty; Gschrey, Manuel; Schlehahn, Alexander; Schmidt, Ronny; Schulze, Jan-Hindrik; Heindel, Tobias; Rodt, Sven, E-mail: srodt@physik.tu-berlin.de; Reitzenstein, Stephan [Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstraße 36, D-10623 Berlin (Germany); Strittmatter, André [Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstraße 36, D-10623 Berlin (Germany); Otto-von-Guericke Universität Magdeburg, Universitätsplatz 2, D-39106 Magdeburg (Germany)

    2015-07-15

    We report on an advanced in-situ electron-beam lithography technique based on high-resolution cathodoluminescence (CL) spectroscopy at low temperatures. The technique has been developed for the deterministic fabrication and quantitative evaluation of nanophotonic structures. It is of particular interest for the realization and optimization of non-classical light sources which require the pre-selection of single quantum dots (QDs) with very specific emission features. The two-step electron-beam lithography process comprises (a) the detailed optical study and selection of target QDs by means of CL-spectroscopy and (b) the precise retrieval of the locations and integration of target QDs into lithographically defined nanostructures. Our technology platform allows for a detailed pre-process determination of important optical and quantum optical properties of the QDs, such as the emission energies of excitonic complexes, the excitonic fine-structure splitting, the carrier dynamics, and the quantum nature of emission. In addition, it enables a direct and precise comparison of the optical properties of a single QD before and after integration which is very beneficial for the quantitative evaluation of cavity-enhanced quantum devices.

  9. A novel lithography process for 3D (three-dimensional) interconnect using an optical direct-writing exposure system

    Science.gov (United States)

    Azuma, T.; Sekiguchi, M.; Matsuo, M.; Kawasaki, A.; Hagiwara, K.; Matsui, H.; Kawamura, N.; Kishimoto, K.; Nakamura, A.; Washio, Y.

    2010-03-01

    A novel lithography process for 3D (Three-dimensional) interconnect was developed using an optical direct-writing exposure tool. A reflective IR (Infra-red) alignment system allows a direct detection of alignment marks both on front-side and back-side of wafer, and consequently allows feasible micro-fabrication for 3D interconnect using the reversed wafer. A combination of the optical direct-writing exposure tool of Dainippon Screen MFG. Co., Ltd. with the reflective IR alignment system and a high aspect chemically amplified resist of Tokyo Ohka Kogyo Co., Ltd. provides the lithography process exclusively for 12-inch wafer level 3D interconnect.

  10. Novel magnetic wire fabrication process by way of nanoimprint lithography for current induced magnetization switching

    Directory of Open Access Journals (Sweden)

    Tsukasa Asari

    2017-05-01

    Full Text Available Nanoimprint lithography (NIL is an effective method to fabricate nanowire because it does not need expensive systems and this process is easier than conventional processes. In this letter, we report the Current Induced Magnetization Switching (CIMS in perpendicularly magnetized Tb-Co alloy nanowire fabricated by NIL. The CIMS in Tb-Co alloy wire was observed by using current pulse under in-plane external magnetic field (HL. We successfully observed the CIMS in Tb-Co wire fabricated by NIL. Additionally, we found that the critical current density (Jc for the CIMS in the Tb-Co wire fabricated by NIL is 4 times smaller than that fabricated by conventional lift-off process under HL = 200Oe. These results indicate that the NIL is effective method for the CIMS.

  11. Ecofriendly ethanol-developable processes for electron beam lithography using positive-tone dextrin resist material

    Science.gov (United States)

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

    2017-07-01

    From the viewpoints of the utilization of agricultural resources and advanced use of biomass, this study is aimed at expanding the resolution limits of ecofriendly ethanol-developable processes for electron-beam lithography using a positive-tone dextrin resist material with high hydrophilicity on a cellulose-based underlayer. The images of 20-nm-hole and 40-nm-line patterns with an exposure dose of approximately 1800 µC/cm2 were provided by ecofriendly ethanol-developable processes instead of the common development processes using tetramethylammonium hydroxide and organic solvents. The CF4 etching selectivity of the positive-tone dextrin resist material was approximately 10% lower than that of the polymethyl methacrylate used as a reference resist material.

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

    Science.gov (United States)

    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.

  13. Modeling and simulation of the deformation process of PTFE flexiblestamps for nanoimprint lithography on curved surfaces

    DEFF Research Database (Denmark)

    Sonne, Mads Rostgaard; Smistrup, K.; Hannibal, Morten

    2015-01-01

    -viscoplastic. This behavior was described in a temperature dependent constitutive model consisting of a Zenerbody for the viscoelastic deformation and the Johnson-Cook model for the description of the viscoplastic deformation. The constitutive model was implemented in the general purpose finite element software ABAQUS...... through a user material subroutine. In order to take the large strains and deformations during the imprinting manufacturing process into account, non-linear geometry was applied in the simulations. The model was first verified through a series of experiments, where nanoimprint lithography on a curved tool...... with a maximum error of 0.5%, indicating that the model is able to capture the physics of this manufacturing process and can be used to give an insight into the nanoimprinting procedure on curved surfaces. (C) 2014 Elsevier B.V. All rights reserved....

  14. Lithography with infrared illumination alignment for advanced BiCMOS backside processing

    Science.gov (United States)

    Kulse, P.; Schulz, K.; Behrendt, U.; Wietstruck, M.; Kaynak, M.; Marschmeyer, S.; Tillack, B.

    2014-10-01

    Driven by new applications such as BiCMOS embedded RF-MEMS, high-Q passives, Si-based microfluidics for bio sensing and InP-Si BiCMOS heterointegration [1-4], accurate alignment between back and front side is highly desired. In this paper, we present an advanced back to front side alignment technique and implementation of it into the back side processing module of IHP's 0.25/0.13 μm high performance SiGe:C BiCMOS technology. Using the Nikon i-line Stepper NSR-SF150, a new infrared alignment system has been introduced. The developed technique enables a high resolution and accurate lithography on the back side of the BiCMOS-processed Si wafers for additional backside processing, such as backside routing metallization. In comparison to previous work [5] with overlay values of 500 nm and the requirement of two-step lithography, the new approach provides significant improvement in the overlay accuracy with overlay values of 200 nm and a significant increase of the fabrication throughput by eliminating the need of the two-step lithography. The new non-contact alignment procedure allows a direct back to front side alignment using any front side alignment mark (Fig. 2), which generated a signal by reflecting the IR light beam. Followed by a measurement of the misalignment between both front to back side overlay marks (Fig. 3) using EVG®NT40 automated measurement system, a final lithography process with wafer interfield corrections is applied to obtain a minimum overlay of 200 nm. For the specific application of deep Si etching using Bosch process, the etch profile angle deviation across the wafer (tilting) has to be considered as well. From experimental data, an etch profile angle deviation of 8 μm across the wafer has been measured (Fig. 7). The overlay error caused by tilting was corrected by optimization and adjustment of the stepper offset parameters. All measurements of back to front side misalignment were performed with the EVG®40NT automated measurement system

  15. Directed self-assembly lithography using coordinated line epitaxy (COOL) process

    Science.gov (United States)

    Seino, Yuriko; Kasahara, Yusuke; Sato, Hironobu; Kobayashi, Katsutoshi; Kubota, Hitoshi; Minegishi, Shinya; Miyagi, Ken; Kanai, Hideki; Kodera, Katsuyoshi; Kihara, Naoko; Kawamonzen, Yoshiaki; Tobana, Toshikatsu; Shiraishi, Masayuki; Nomura, Satoshi; Azuma, Tsukasa

    2015-03-01

    In this study, half-pitch (HP) 15 nm line-and-space (L/S) metal wires were successfully fabricated and fully integrated on a 300 mm wafer by applying directed self-assembly (DSA) lithography and pattern transfer for semiconductor device manufacturing. In order to evaluate process performances of DSA, we developed a simple sub-15 nm L/S patterning process using polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) lamellar block copolymer (BCP), which utilizes trimming resist and shallow etching spin-on-glass (SOG) as pinning guide[1]-[4]. From the results of defect inspection after SOG etch using Electron Beam (EB) inspection system, defects were classified as typical DSA defects or defects relating to DSA pattern transfer. From the evaluation of DSA L/S pattern Critical Dimension (CD), roughness and local placement error using CD-SEM, it is considered that isolated PS lines are placed at the centerline between guides and that placement of paired PS lines depends on the guide width. The control of the guide resist CD is the key to local placement error and the paired lines adjacent to the guide shifted toward the outside (0.5 nm) along the centerline of the isolated line after SOG etch. We demonstrated fabrication of HP 15 nm metal wires in trenches formed by the DSA process with reactive ion etching (RIE), followed by metal chemical vapor deposition (CVD) and chemical mechanical polishing (CMP). By SEM observation of alignment errors between the trenches and connect spaces, overlay shift patterns (-4 nm) in guide lithography mask were fabricated without intra-wafer alignment errors.

  16. Nano lithography

    CERN Document Server

    Landis, Stefan

    2013-01-01

    Lithography is an extremely complex tool - based on the concept of "imprinting" an original template version onto mass output - originally using relatively simple optical exposure, masking, and etching techniques, and now extended to include exposure to X-rays, high energy UV light, and electron beams - in processes developed to manufacture everyday products including those in the realms of consumer electronics, telecommunications, entertainment, and transportation, to name but a few. In the last few years, researchers and engineers have pushed the envelope of fields including optics, physics,

  17. Mechanical processes with repeated attenuated impacts

    CERN Document Server

    Nagaev, R F

    1999-01-01

    This book is devoted to considering in the general case - using typical concrete examples - the motion of machines and mechanisms of impact and vibro-impact action accompanied by a peculiar phenomenon called "impact collapse". This phenomenon is that after the initial collision, a sequence of repeated gradually quickening collisions of decreasing-to-zero intensity occurs, with the final establishment of protracted contact between the interacting bodies. The initiation conditions of the impact collapse are determined and calculation techniques for the quantitative characteristics of the corresp

  18. Airborne Radar Interferometric Repeat-Pass Processing

    Science.gov (United States)

    Hensley, Scott; Michel, Thierry R.; Jones, Cathleen E.; Muellerschoen, Ronald J.; Chapman, Bruce D.; Fore, Alexander; Simard, Marc; Zebker, Howard A.

    2011-01-01

    Earth science research often requires crustal deformation measurements at a variety of time scales, from seconds to decades. Although satellites have been used for repeat-track interferometric (RTI) synthetic-aperture-radar (SAR) mapping for close to 20 years, RTI is much more difficult to implement from an airborne platform owing to the irregular trajectory of the aircraft compared with microwave imaging radar wavelengths. Two basic requirements for robust airborne repeat-pass radar interferometry include the ability to fly the platform to a desired trajectory within a narrow tube and the ability to have the radar beam pointed in a desired direction to a fraction of a beam width. Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) is equipped with a precision auto pilot developed by NASA Dryden that allows the platform, a Gulfstream III, to nominally fly within a 5 m diameter tube and with an electronically scanned antenna to position the radar beam to a fraction of a beam width based on INU (inertial navigation unit) attitude angle measurements.

  19. Expanding the printable design space for lithography processes utilizing a cut mask

    Science.gov (United States)

    Wandell, Jerome; Salama, Mohamed; Wilkinson, William; Curtice, Mark; Feng, Jui-Hsuan; Gao, Shao Wen; Asthana, Abhishek

    2016-03-01

    The utilization of a cut-mask in semiconductor patterning processes has been in practice for logic devices since the inception of 32nm-node devices, notably with unidirectional gate level printing. However, the microprocessor applications where cut-mask patterning methods are used are expanding as Self-Aligned Double Patterning (SADP) processes become mainstream for 22/14nm fin diffusion, and sub-14nm metal levels. One common weakness for these types of lithography processes is that the initial pattern requiring the follow-up cut-mask typically uses an extreme off-axis imaging source such as dipole to enhance the resolution and line-width roughness (LWR) for critical dense patterns. This source condition suffers from poor process margin in the semi-dense (forbidden pitch) realm and wrong-way directional design spaces. Common pattern failures in these limited design regions include bridging and extra-printing defects that are difficult to resolve with traditional mask improvement means. This forces the device maker to limit the allowable geometries that a designer may use on a device layer. This paper will demonstrate methods to expand the usable design space on dipole-like processes such as unidirectional gate and SADP processes by utilizing the follow-up cut mask to improve the process window. Traditional mask enhancement means for improving the process window in this design realm will be compared to this new cut-mask approach. The unique advantages and disadvantages of the cut-mask solution will be discussed in contrast to those customary methods.

  20. Influence of mold and substrate material combinations on nanoimprint lithography process: MD simulation approach

    Science.gov (United States)

    Yang, Seunghwa; Yu, Suyoung; Cho, Maenghyo

    2014-05-01

    A molecular dynamics (MD) study was performed to examine the effect of mold-substrate material composition on the pattern transferring and defects of the resist polymer in a thermal Nano Imprint Lithography (NIL) process. As candidate materials, single crystalline nickel (Ni), silicon (Si) and silica (SiO2, α-quartz) for the rigid mold substrate, and amorphous poly-(methylmethacrylate) (PMMA) thin film for the resist were considered for common applications in NIL processes. Three different material compositions of Si mold-Ni substrate, Ni mold-Si substrate, and quartz mold-Ni substrate were considered. In accordance with a real NIL process, a sequence of indentation-relaxation-release processes was quasi-statically simulated using isothermal ensemble simulation on tri-layer molecular structures consisting of a mold, resist, and substrate. To correlate the deformed shape and delamination of PMMA resist from the substrate in indentation and release processes, non-bond interaction energy between a rigid mold and resist was calculated for each combination of mold and substrate materials. The Si mold-Ni substrate combination shows successful pattern transfer to the resist polymer even without an anti-sticking layer as a result of the desirable balance of surface free energy for mold and substrate materials. However, Ni mold-Si substrate combination shows a critical delamination of the resist in the release process due to strong van der Waals adhesion between the resist and Ni mold. Similarly, the quartz mold-Ni substrate combination shows the same delamination in pattern transfer, but the adhesion of the resist to the quartz mold is attributed to electrostatic interaction. In order to provide guidelines for material selection in imprint-like processes where surface adsorption and wetting characteristics are critical design parameters, a simple PMMA-rigid plate model is proposed, with which consistent surface interaction characteristics in the full model NIL process

  1. Fundamental study of green EUV lithography using natural polysaccharide for the use of pure water in developable process

    Science.gov (United States)

    Takei, Satoshi

    2016-10-01

    The eco-conscious lithography processes of using pure water instead of spin coating organic solvent and alkaline developer were described for extreme-ultraviolet and electron beam techniques of advanced photomask manufactural application. Natural polysaccharide was obtained by the esterification of the hydroxyl groups of the polysaccharide resulting in improved resolution and resist profiles after the purewater developing processes. The 100, 200, and, 300 nm line and space width, and straight profiles of polysaccharide-based resist material on hardmask underlayer were resolved at the doses of 30 μC/cm2. In addition to the superior resolution in the pure-water developing processes, the resist material containing the polysaccharide derivatives for these lithography showed good resist profiles and step filling performance on substrates.

  2. Design and implementation of a cloud based lithography illumination pupil processing application

    Science.gov (United States)

    Zhang, Youbao; Ma, Xinghua; Zhu, Jing; Zhang, Fang; Huang, Huijie

    2017-02-01

    Pupil parameters are important parameters to evaluate the quality of lithography illumination system. In this paper, a cloud based full-featured pupil processing application is implemented. A web browser is used for the UI (User Interface), the websocket protocol and JSON format are used for the communication between the client and the server, and the computing part is implemented in the server side, where the application integrated a variety of high quality professional libraries, such as image processing libraries libvips and ImageMagic, automatic reporting system latex, etc., to support the program. The cloud based framework takes advantage of server's superior computing power and rich software collections, and the program could run anywhere there is a modern browser due to its web UI design. Compared to the traditional way of software operation model: purchased, licensed, shipped, downloaded, installed, maintained, and upgraded, the new cloud based approach, which is no installation, easy to use and maintenance, opens up a new way. Cloud based application probably is the future of the software development.

  3. Dual damascene BEOL processing using multilevel step and flash imprint lithography

    Science.gov (United States)

    Chao, Brook H.; Palmieri, Frank; Jen, Wei-Lun; McMichael, D. Hale; Willson, C. Grant; Owens, Jordan; Berger, Rich; Sotoodeh, Ken; Wilks, Bruce; Pham, Joseph; Carpio, Ronald; LaBelle, Ed; Wetzel, Jeff

    2008-03-01

    Step and Flash Imprint Lithography (S-FIL®) in conjunction with Sacrificial Imprint Materials (SIM) shows promise as a cost effective solution to patterning sub 45nm features and is capable of simultaneously patterning two levels of interconnect structures, which provides a high throughput and low cost BEOL process. This paper describes the integration of S-FIL into an industry standard Cu/low-k dual damascene process that is being practiced in the ATDF at Sematech in Austin. The pattern transferring reactive ion etching (RIE) process is the most critical step and was extensively explored in this study. In addition to successful process development, the results provide useful insight into the optimal design of multilevel templates which must take into account the characteristics of both the imaging material and the dielectric layer. The template used in this study incorporates both the via and trench levels of an M2 (Metal 2) test vehicle that incorporates via chains with varying via dimensions, Kelvin test structures, serpentines, etc. The smallest vias on the template are 120nm vias with an aspect ratio of 2.0 and the smallest dense lines are 125nm/175nm with an aspect ratio of 2.9. Two inter-level dielectrics (ILD), Coral® and Black Diamond® were studied. No trench etch stop was incorporated in the ILD film stack. A multi-step, in-situ etching scheme was developed that achieves faithful pattern transfer from the sacrificial imprint material (SIM) into the underlying low k ILD with surprisingly wide process latitude. This multi-step scheme includes the following etch steps: a residual layer open, a via etch, a trench descum, a trench etch, and an SIM removal ash. Among these steps, the trench etch was found to be the most challenging to develop and it holds the key to producing high aspect ratio dual damascene features. An etching chemistry based on two fluorocarbon gases, CF 4 and C 4F 8, was found to be very effective in delivering the desired etch profiles

  4. Modeling and process design for laser interference lithography used in fabricating two-dimensional periodic structures

    NARCIS (Netherlands)

    Bostan, C.G.; Ridder, de R.M.; Dorssen, van I.; Wolferen, van H.A.G.M.; Kuipers, L.; Hulst, van N.F.

    2002-01-01

    Laser interference lithography (LIL) is a technique that can be successfully used for realization of 2D periodic structures, with excellent uniformity over large areas. However, detailed modeling is needed in order to extract the optimum design parameters. In this paper, we refer to a design procedu

  5. Finger-powered microfluidic systems using multilayer soft lithography and injection molding processes.

    Science.gov (United States)

    Iwai, Kosuke; Shih, Kuan Cheng; Lin, Xiao; Brubaker, Thomas A; Sochol, Ryan D; Lin, Liwei

    2014-10-07

    Point-of-care (POC) and disposable biomedical applications demand low-power microfluidic systems with pumping components that provide controlled pressure sources. Unfortunately, external pumps have hindered the implementation of such microfluidic systems due to limitations associated with portability and power requirements. Here, we propose and demonstrate a 'finger-powered' integrated pumping system as a modular element to provide pressure head for a variety of advanced microfluidic applications, including finger-powered on-chip microdroplet generation. By utilizing a human finger for the actuation force, electrical power sources that are typically needed to generate pressure head were obviated. Passive fluidic diodes were designed and implemented to enable distinct fluids from multiple inlet ports to be pumped using a single actuation source. Both multilayer soft lithography and injection molding processes were investigated for device fabrication and performance. Experimental results revealed that the pressure head generated from a human finger could be tuned based on the geometric characteristics of the pumping system, with a maximum observed pressure of 7.6 ± 0.1 kPa. In addition to the delivery of multiple, distinct fluids into microfluidic channels, we also employed the finger-powered pumping system to achieve the rapid formation of both water-in-oil droplets (106.9 ± 4.3 μm in diameter) and oil-in-water droplets (75.3 ± 12.6 μm in diameter) as well as the encapsulation of endothelial cells in droplets without using any external or electrical controllers.

  6. Fabrication of sub-12 nm thick silicon nanowires by processing scanning probe lithography masks

    Energy Technology Data Exchange (ETDEWEB)

    Kyoung Ryu, Yu; Garcia, Ricardo, E-mail: r.garcia@csic.es [Instituto de Ciencia de Materiales de Madrid, CSIC, Sor Juana Inés de la Cruz 3, 28049 Madrid (Spain); Aitor Postigo, Pablo; Garcia, Fernando [Instituto de Microelectrónica de Madrid (IMM-CNM-CSIC), 28760 Tres Cantos, Madrid (Spain)

    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 with a top-down lithography method.

  7. Distributed processing (DP) based e-beam lithography simulation with long range correction algorithm in e-beam machine

    Science.gov (United States)

    Ki, Won-Tai; Choi, Ji-Hyeon; Kim, Byung-Gook; Woo, Sang-Gyun; Cho, Han-Ku

    2008-05-01

    As the design rule with wafer process is getting smaller down below 50nm node, the specification of CDs on a mask is getting more tightened. Therefore, more tight and accurate E-Beam Lithography simulation is highly required in these days. However, in reality most of E-Beam simulation cases, there is a trade-off relationship between the accuracy and the simulation speed. Moreover, the necessity of full chip based simulation has been increasing in order to estimate more accurate mask CDs based on real process condition. Therefore, without consideration of long range correction algorithm such as fogging effect and loading effect correction in E-beam machine, it would be impossible and meaningless to pursue the full chip based simulation. In this paper, we introduce a breakthrough method to overcome the obstacles of E-Beam simulation. In-house E-beam simulator, ELIS (E-beam LIthography Simulator), has been upgraded to solve these problems. First, DP (Distributed Processing) strategy was applied to improve calculation speed. Secondly, the long range correction algorithm of E-beam machine was also applied to compute intensity of exposure on a full chip based (Mask). Finally, ELIS-DP has been evaluated possibility of expecting or analyzing CDs on full chip base.

  8. A Repeatable Collaboration Process for Exploring Business Process Improvement Alternatives

    NARCIS (Netherlands)

    Sol, H G; Amiyo, Mercy; Nabukenya, J.

    2012-01-01

    The dynamic nature of organisations has increased demand for business process agility leading to the adoption of continuous Business Process Improvement (BPI). Success of BPI projects calls for continuous process analysis and exploration of several improvement alternatives. These activities are

  9. Echelle grating for silicon photonics applications: integration of electron beam lithography in the process flow and first results

    Science.gov (United States)

    Kaschel, Mathias; Letzkus, Florian; Butschke, Jörg; Skwierawski, Piotr; Schneider, Marc; Weber, Marc

    2016-05-01

    We present the technology steps to integrate an Echelle grating in the process flow of silicon-organic hybrid (SOH) modulators or related active devices. The CMOS-compatible process flow on SOI substrates uses a mix of optical i-line lithography and electron beam lithography (EBL). High speed optical data communication depends on wavelength divisions multiplexing and de-multiplexing devices like Echelle gratings. The minimum feature sizes vary from device to device and reach down to 60 nm inside a modulator, while the total area of a single Echelle grating is up to several mm2 of unprocessed silicon. Resist patterning using a variable shape beam electron beam pattern generator allows high resolution. An oxide hard mask is deposited, patterns are structured threefold by EBL and are later transferred to the silicon. We demonstrate a 9-channel multiplexer featuring a 2 dB on-chip loss and an adjacent channel crosstalk better than -22 dB. Additionally a 45-channel Echelle multiplexer is presented with 5 dB on chip loss and a channel crosstalk better than -12 dB. The devices cover an on-chip area of only 0.08 mm2 and 0.5 mm2 with a wavelength spacing of 10.5 nm and 2.0 nm, respectively.

  10. Coaxial Lithography

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  12. Plasmonic films based on colloidal lithography.

    Science.gov (United States)

    Ai, Bin; Yu, Ye; Möhwald, Helmuth; Zhang, Gang; Yang, Bai

    2014-04-01

    This paper reviews recent advances in the field of plasmonic films fabricated by colloidal lithography. Compared with conventional lithography techniques such as electron beam lithography and focused ion beam lithography, the unconventional colloidal lithography technique with advantages of low-cost and high-throughput has made the fabrication process more efficient, and moreover brought out novel films that show remarkable surface plasmon features. These plasmonic films include those with nanohole arrays, nanovoid arrays and nanoshell arrays with precisely controlled shapes, sizes, and spacing. Based on these novel nanostructures, optical and sensing performances can be greatly enhanced. The introduction of colloidal lithography provides not only efficient fabrication processes but also plasmonic films with unique nanostructures, which are difficult to be fabricated by conventional lithography techniques.

  13. Fabrication of a silicon oxide stamp by edge lithography reinforced with silicon nitride for nanoimprint lithography

    NARCIS (Netherlands)

    Zhao, Yiping; Berenschot, Johan W.; de Boer, M.; de Boer, Meint J.; Jansen, Henricus V.; Tas, Niels Roelof; Huskens, Jurriaan; Elwenspoek, Michael Curt

    2008-01-01

    The fabrication of a stamp reinforced with silicon nitride is presented for its use in nanoimprint lithography. The fabrication process is based on edge lithography using conventional optical lithography and wet anisotropic etching of 110 silicon wafers. SiO2 nano-ridges of 20 nm in width were

  14. Hybrid quantum repeater protocol with fast local processing

    DEFF Research Database (Denmark)

    Borregaard, Johannes; Brask, Jonatan Bohr; Sørensen, Anders Søndberg

    2012-01-01

    the need for classical communication during growth. Entanglement is generated in subsequent connection processes. Furthermore the growth procedure is optimized. We review the main elements of the original protocol and present the two modifications. Finally the two protocols are compared and the modified......We propose a hybrid quantum repeater protocol combining the advantages of continuous and discrete variables. The repeater is based on the previous work of Brask et al. [ Phys. Rev. Lett. 105 160501 (2010)] but we present two ways of improving this protocol. In the previous protocol entangled single......-photon states are produced and grown into superpositions of coherent states, known as two-mode cat states. The entanglement is then distributed using homodyne detection. To improve the protocol, we replace the time-consuming nonlocal growth of cat states with local growth of single-mode cat states, eliminating...

  15. A combined electron beam/optical lithography process step for the fabrication of sub-half-micron-gate-length MMIC chips

    Science.gov (United States)

    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

  16. Repeater-Assisted Zeno Effect in Classical Stochastic Processes

    Institute of Scientific and Technical Information of China (English)

    GU Shi-Jian; WANG Li-Gang; WANG Zhi-Guo; LIN Hai-Qing

    2012-01-01

    We address the possibility of the classical Zeno effect in classical stochastic processes as sampled by transferring a digitized image through a classical channel with surrounding noise. It is shown that the the classical state of the image decays inevitably with the distance of the channel due to the interference of the surroundings. However, if there are enough repeaters, which can both check and recover the state's information, the classical state's decay rate will be significantly suppressed, then a classical Zeno effect might occur.%We address the possibility of the classical Zeno effect in classical stochastic processes as sampled by transferring a digitized image through a classical channel with surrounding noise.It is shown that the the classical state of the image decays inevitably with the distance of the channel due to the interference of the surroundings.However,if there are enough repeaters,which can both check and recover the state's information,the classical state's decay rate will be significantly suppressed,then a classical Zeno effect might occur.

  17. Impact of polymer film thickness and cavity size on polymer flow during embossing : towards process design rules for nanoimprint lithography.

    Energy Technology Data Exchange (ETDEWEB)

    Schunk, Peter Randall; King, William P. (Georgia Institute of Technology, Atlanta, GA); Sun, Amy Cha-Tien; Rowland, Harry D. (Georgia Institute of Technology, Atlanta, GA)

    2006-08-01

    This paper presents continuum simulations of polymer flow during nanoimprint lithography (NIL). The simulations capture the underlying physics of polymer flow from the nanometer to millimeter length scale and examine geometry and thermophysical process quantities affecting cavity filling. Variations in embossing tool geometry and polymer film thickness during viscous flow distinguish different flow driving mechanisms. Three parameters can predict polymer deformation mode: cavity width to polymer thickness ratio, polymer supply ratio, and Capillary number. The ratio of cavity width to initial polymer film thickness determines vertically or laterally dominant deformation. The ratio of indenter width to residual film thickness measures polymer supply beneath the indenter which determines Stokes or squeeze flow. The local geometry ratios can predict a fill time based on laminar flow between plates, Stokes flow, or squeeze flow. Characteristic NIL capillary number based on geometry-dependent fill time distinguishes between capillary or viscous driven flows. The three parameters predict filling modes observed in published studies of NIL deformation over nanometer to millimeter length scales. The work seeks to establish process design rules for NIL and to provide tools for the rational design of NIL master templates, resist polymers, and process parameters.

  18. Nanohole and dot patterning processes on quartz substrate by R-θ electron beam lithography and nanoimprinting

    Science.gov (United States)

    Watanabe, Tsuyoshi; Taniguchi, Kazutake; Suzuki, Kouta; Iyama, Hiromasa; Kishimoto, Shuji; Sato, Takashi; Kobayashi, Hideo

    2016-06-01

    Fine hole and dot patterns with bit pitches (bp’s) of less than 40 nm were fabricated in the circular band area of a quartz substrate by R-θ electron beam lithography (EBL), reactive ion etching (RIE), and nanoimprinting. These patterning processes were studied to obtain minimum pitch sizes of hole and dot patterns without pattern collapse. The patterning on the circular band was aimed to apply these patterning processes to future high-density bit-patterned media (BPM) for hard disk drive (HDD) and permanent memory for the long life archiving of digital data. In hole patterning, a minimum-22-nm-bp and 8.2-nm-diameter pattern (1.3 Tbit/in.2) was obtained on a quartz substrate by optimizing the R-θ EBL and RIE processes. Dot patterns were replicated on another quartz substrate by nanoimprinting using a hole-patterned quartz substrate as a master mold followed by RIE. In dot patterning, a minimum-30-nm-bp and 18.5-nm-diameter pattern (0.7 Tbit/in.2) was obtained by introducing new descum conditions. It was observed that the minimum bp of successful patterning increased as the fabrication process proceeded, i.e., from 20 nm bp in the first EBL process to 30 nm bp in the last quartz dot patterning process. From the measured diameters of the patterns, it was revealed that pattern collapse was apt to occur when the value of average diameter plus 3 sigma of diameter was close to the bp. It was suggested that multiple fabrication processes caused the degradation of pattern quality; therefore, hole patterning is more suitable than dot patterning for future applications owing to the lower quality degradation by its simple fabrication process.

  19. Lithography for VLSI

    CERN Document Server

    Einspruch, Norman G

    1987-01-01

    VLSI Electronics Microstructure Science, Volume 16: Lithography for VLSI treats special topics from each branch of lithography, and also contains general discussion of some lithographic methods.This volume contains 8 chapters that discuss the various aspects of lithography. Chapters 1 and 2 are devoted to optical lithography. Chapter 3 covers electron lithography in general, and Chapter 4 discusses electron resist exposure modeling. Chapter 5 presents the fundamentals of ion-beam lithography. Mask/wafer alignment for x-ray proximity printing and for optical lithography is tackled in Chapter 6.

  20. Coaxial lithography.

    Science.gov (United States)

    Ozel, Tuncay; Bourret, Gilles R; Mirkin, Chad A

    2015-04-01

    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 nanowire that can be created and studied in the laboratory. Here, we report a high-throughput technique that can be used to prepare coaxial nanowires with sub-10 nm control over the architectural parameters in both axial and radial dimensions. The method, termed coaxial lithography (COAL), relies on templated electrochemical synthesis and can create coaxial nanowires composed of combinations of metals, metal oxides, metal chalcogenides and conjugated polymers. To illustrate the possibilities of the technique, a core/shell semiconductor nanowire with an embedded plasmonic nanoring was synthesized--a structure that cannot be prepared by any previously known method--and its plasmon-excitation-dependent optoelectronic properties were characterized.

  1. Maskless lithography

    Science.gov (United States)

    Sweatt, William C.; Stulen, Richard H.

    1999-01-01

    The present invention provides a method for maskless lithography. A plurality of individually addressable and rotatable micromirrors together comprise a two-dimensional array of micromirrors. Each micromirror in the two-dimensional array can be envisioned as an individually addressable element in the picture that comprises the circuit pattern desired. As each micromirror is addressed it rotates so as to reflect light from a light source onto a portion of the photoresist coated wafer thereby forming a pixel within the circuit pattern. By electronically addressing a two-dimensional array of these micromirrors in the proper sequence a circuit pattern that is comprised of these individual pixels can be constructed on a microchip. The reflecting surface of the micromirror is configured in such a way as to overcome coherence and diffraction effects in order to produce circuit elements having straight sides.

  2. VUV lithography

    Science.gov (United States)

    George, Edward V.; Oster, Yale; Mundinger, David C.

    1990-01-01

    Deep UV projection lithography can be performed using an e-beam pumped solid excimer UV source, a mask, and a UV reduction camera. The UV source produces deep UV radiation in the range 1700-1300A using xenon, krypton or argon; shorter wavelengths of 850-650A can be obtained using neon or helium. A thin solid layer of the gas is formed on a cryogenically cooled plate and bombarded with an e-beam to cause fluorescence. The UV reduction camera utilizes multilayer mirrors having high reflectivity at the UV wavelength and images the mask onto a resist coated substrate at a preselected demagnification. The mask can be formed integrally with the source as an emitting mask.

  3. Step & flash imprint lithography

    Directory of Open Access Journals (Sweden)

    Douglas J. Resnick

    2005-02-01

    Full Text Available The escalating cost of next generation lithography (NGL is driven in part by the need for complex sources and optics. The cost for a single NGL tool could soon exceed $50 million, a prohibitive amount for many companies. As a result, several research groups are looking at alternative, low-cost methods for printing sub-100 nm features. Many of these methods are limited in their ability to do precise overlay. In 1999, Willson and Sreenivasan developed step and flash imprint lithography (S-FIL™. The use of a quartz template opens up the potential for optical alignment of the wafer and template. This paper reviews several key aspects of the S-FIL process, including template, tool, ultraviolet (UV-curable monomer, and pattern transfer. Two applications are also presented: contact holes and surface acoustic wave (SAW filters.

  4. Challenges for immersion lithography extension based on negative tone imaging (NTI) process

    Science.gov (United States)

    Shirakawa, Michihiro; Omatsu, Tadashi; Ou, Keiyu; Yonekuta, Yasunori; Hatakeyama, Naoya; Asakawa, Daisuke; Yakushiji, Takashi; Fujita, Mitsuhiro; Muraki, Nanae

    2016-03-01

    Negative tone imaging (NTI) process is a method for obtaining a negative-tone reversal pattern by developing with an organic solvent. As NTI process can break-through the resolution limit of a conventional positive tone development (PTD) process at specific pattern such as trenches and contact holes, it have been applied for a mass production in 20nm and 14nm nodes devices. In NTI system, because a developer is changed from a hydrophilic aqueous solution to a hydrophobic organic solvent, it is possible to review the common resist stack which is optimized for a PTD process. In this paper, we examined the possibility of a bi-layer process using a Si-containing NTI resist. Etching selectivity between the Si-NTI resist and a SOC improved by raising Si-content of the Si-NTI resist, but resolution deteriorates as a trade-off. By suppressing swelling behavior of the Si-NTI resist with a polymer structure control, we overcame this trade-off. As a result, in sub-90 nm pitch L/S and CH patterns, the resolution of the Si-NTI resist achieved comparable level to a conventional NTI resist. In addition, SOC etching was successfully carried out by using the Si-NTI resist pattern as an etching hard mask.

  5. Development of an i-line attenuated phase shift process for dual inlay interconnect lithography

    Science.gov (United States)

    Sturtevant, John L.; Ho, Benjamin C. P.; Geiszler, Vincent C.; Herrick, Matthew T.; King, Charles F.; Carter, Russell L.; Roman, Bernard J.; Litt, Lloyd C.; Smith, Brad; Strozewski, Kirk J.

    2000-06-01

    The transition from aluminum/oxide to copper/low-k dielectric interconnect technology involves a variety of fundamental changes in the back-end manufacturing process. The most attractive patterning strategy involves the use of a so-called dual inlay approach, which offers lower fabrication costs by the elimination of one inter-level dielectric (ILD) deposition and polish sequence per metal layer. In this paper, the lithographic challenges for dual inlay, including thin-film interference effect, resist bulk effect, and optical proximity effects are reviewed. The use of attenuated phase shift (aPSM) reticles for patterning vias and trenches was investigated, and shown to provide adequate process margin by optimizing the photoresist and exposure tool parameters. Our results indicate that using appropriately sized attenuated phase shift technique increases the photospeed considerably and simultaneously improves the common process window with sufficient sidelobe suppression margin. The cost of ownership tradeoffs between an attenuated PSM I-Line process and a DUV binary process are discussed.

  6. Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

    Institute of Scientific and Technical Information of China (English)

    R.Pelzer; P.Lindner; T.Glinsner; B.Vratzov; C.Gourgon; S.Landis; P.Kettner; C.Schaefer

    2004-01-01

    Nanoimprint Lithography has been demonstrated to be one of the most promising next generation techniques for large-area structure replication in the nanometer scale.This fast and low cost method becomes an increasingly important instrument for fabrication of biochemistry,μ-fluidic,μ-TAS and telecommunication devices,as well as for a wide variety of fields in the nm range,like biomedical,nano-fluidics,nano-optical applications,data storage,etc.Due to the restrictions on wavelength and the enormous development works,linked to high process and equipment costs on standard lithography systems,nanoimprint lithography might become a real competitive method in mainstream IC industry.There are no physical limitations encountered with imprinting techniques for much smaller replicated structures,down to the sub-10nm range [1].Among several Nanoimprint lithography techniques results of two promising methods,hot embossing lithography(HEL)and UV-nanoimprinting(UV-NIL)will be presented.Both techniques allow rapid prototyping as well as high volume production of fully patterned substrates for a wide range of materials.This paper will present results on HE and UVNIL,among them full wafer imprints up to 200mm with high-resolution patterns down to nm range.

  7. Two-layer critical dimensions and overlay process window characterization and improvement in full-chip computational lithography

    Science.gov (United States)

    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.

  8. A process study of electron beam nano-lithography and deep etching with an ICP system

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A systemic process study on an electron beam nanolithography system operating at 100kV was pre-sent.The exposure conditions were optimized for resist ZEP520A.Grating structures with line/space of 50nm/50nm were obtained in a reasonably thick resist which is beneficial to the subsequent pattern transfer technique.The ICP etching process conditions was optimized.The role of etching parameters such as source power,gas pressure,and gas flow rate on the etching result was also discussed.A grating structure with line widths as small as 100nm,duty cycles of 0.5,depth of 900nm,and the side-wall scalloping as small as 5nm on a silicon substrate was obtained.The silicon deep etching technique for structure sizes smaller than 100nm is very important for the fabrication of nano-optical devices working in the visible regime.

  9. Integrating nanosphere lithography in device fabrication

    Science.gov (United States)

    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.

  10. Self-Collapse Lithography.

    Science.gov (United States)

    Zhao, Chuanzhen; Xu, Xiaobin; Yang, Qing; Man, Tianxing; Jonas, Steven J; Schwartz, Jeffrey J; Andrews, Anne M; Weiss, Paul S

    2017-08-09

    We report a facile, high-throughput soft lithography process that utilizes nanoscale channels formed naturally at the edges of microscale relief features on soft, elastomeric stamps. Upon contact with self-assembled monolayer (SAM) functionalized substrates, the roof of the stamp collapses, resulting in the selective removal of SAM molecules via a chemical lift-off process. With this technique, which we call self-collapse lithography (SCL), sub-30 nm patterns were achieved readily using masters with microscale features prepared by conventional photolithography. The feature sizes of the chemical patterns can be varied continuously from ∼2 μm to below 30 nm by decreasing stamp relief heights from 1 μm to 50 nm. Likewise, for fixed relief heights, reducing the stamp Young's modulus from ∼2.0 to ∼0.8 MPa resulted in shrinking the features of resulting patterns from ∼400 to ∼100 nm. The self-collapse mechanism was studied using finite element simulation methods to model the competition between adhesion and restoring stresses during patterning. These results correlate well with the experimental data and reveal the relationship between the line widths, channel heights, and Young's moduli of the stamps. In addition, SCL was applied to pattern two-dimensional arrays of circles and squares. These chemical patterns served as resists during etching processes to transfer patterns to the underlying materials (e.g., gold nanostructures). This work provides new insights into the natural propensity of elastomeric stamps to self-collapse and demonstrates a means of exploiting this behavior to achieve patterning via nanoscale chemical lift-off lithography.

  11. Hybrid quantum repeater protocol with fast local processing

    DEFF Research Database (Denmark)

    Borregaard, Johannes; Brask, Jonatan Bohr; Sørensen, Anders Søndberg

    2012-01-01

    We propose a hybrid quantum repeater protocol combining the advantages of continuous and discrete variables. The repeater is based on the previous work of Brask et al. [ Phys. Rev. Lett. 105 160501 (2010)] but we present two ways of improving this protocol. In the previous protocol entangled single......-photon states are produced and grown into superpositions of coherent states, known as two-mode cat states. The entanglement is then distributed using homodyne detection. To improve the protocol, we replace the time-consuming nonlocal growth of cat states with local growth of single-mode cat states, eliminating...

  12. Fabrication of metallic nanostructures of sub-20 nm with an optimized process of E-beam lithography and lift-off

    KAUST Repository

    Yue, Weisheng

    2012-01-01

    A process consisting of e-beam lithography and lift-off was optimized to fabricate metallic nanostructures. This optimized process successfully produced gold and aluminum nanostructures with features size less than 20 nm. These structures range from simple parallel lines to complex photonic structures. Optical properties of gold split ring resonators (SRRs) were characterized with Raman spectroscopy. Surface-Enhanced Raman Scattering (SERS) on SRRs was observed with 4-mercaptopyridine (4-MPy) as molecular probe and greatly enhanced Raman scattering was observed. Copyright © 2012 American Scientific Publishers.

  13. Some properties of repeated hits after first explosion for birth and death processes

    Institute of Scientific and Technical Information of China (English)

    杨向群

    1999-01-01

    Of repeated hits and repeated explosions after first explosion for a birth and death process with explosion some properties are investigated. The properties of repeated hits after first explosion may be expressed by the properties of the first hit after the first explosion.

  14. Research Analysis of RtR Control Method for Lithography Process%光刻过程RtR控制方法研究进展分析

    Institute of Scientific and Technical Information of China (English)

    王亮; 胡静涛

    2011-01-01

    Firstly, the lithography process and background of RtR control technique were introduced.The shortage of statistical process control was analyzed and the general structure of the RtR controller was given. Then, an overview and evaluation about EWMA, MPC and ANN controllers of the lithography process were given in the ways of modeling and control algorithms. Besides, the comparative analysis of the nonlinear control, SISO control, MISO control, MIMO control and optimization control quality of three controllers were presented. Finally, it is proposed that the multivariable nonlinear controllers based on MPC become the future development direction of the lithography process RtR controller.%首先对光刻过程和RtR (Run-to-Run)控制技术的产生背景进行了介绍,对统计过程控制的不足进行了分析并给出了RtR控制器的一般结构.然后从过程建模和控制算法两个角度对三种主要的光刻过程RtR控制器EWMA,MPC和ANN进行了综述和评价,对这三种控制器在非线性控制、单变量控制、多变童控制的适用性和优化控制效果进行了比较分析.最后指出基于MPC的非线性多变量控制器将成为光刻过程RtR控制器的主要研究方向.

  15. Sub-Half Micrometer Gate Lift-Off By Three Layer Resist Process Via Electron Beam Lithography For Gallium Arsenide Monolithic Microwave Integrated Circuits (MIMICs)

    Science.gov (United States)

    Nagarajan, Rao M.; Rask, Steven D.; King, Michael R.; Yard, Thomas K.

    1988-06-01

    A three layer resist process for gate lift-oft on Gallium Arsenide MIMICs by electron Dean and optical lithographies are described. The electron beam lithography process consists of Poly (Dimethyl Glutarimide) PMGI as tne planarizing layer, a Plasma Enhanced Chemical Vapour Deposition silicon nitride (SiN) as an intermediate barrier layer and Poly (Methyl methacrylate), PMMA, as the top imaging layer. The PivimA is exposed by Cambridge Electron beam system EBMF 6.4 at 20kev and developed in Methyl Ethyl Ketone/Iso Propyl Alcohol. The pattern is then transferred to the SiN layer by cF4/o2 plasma etcning. The SiN layer is then used as the mask to transfer the pattern to the PMGI layer by 02 kteactive Ion Etching until tne GaAS is exposed. The various processing parameters are optimized to obtain lip or overnang suitable for lift-off with 0.20μm gate dimension. After the GaAS has been recessed (to reduce the parasitic source resistance), a thick 9000Å Ti/Pt/Au gate metal is evaporated and the unwanted gate metal is lifted oft using PMGI stripper. To use the three layer resist process in optical litnograpny, the MG.'. planarizing layer and PECVD SiN layer is used along with optical pnotoresist AZ1450J as a top imaging layer. inc sofcbake, uV exposure dose (436 nm) and development time for AZ145UJ are optimized to obtain 0.5μm to 1.0μm gate dimensions. The etch parameters for the pattern transfer to SiN and tnen to PMGI layers are same as in tne above process. The process levels such as mesa, source/drain, contact and metal levels for GaAs mlivilt,s are defined by UV lithography (Karl Suss contact aligner) using single layer pnotoresist. A nign overlay accuracy is obtained by use of gold metal Dumps as registration marks for aligning tne electron Dean exposed gate to optically exposed source/drain channel. Thus a higher tnrougnput and better linewidtn control are obtained using electron beam/optical lithography tecnniques. This approach is currently used to

  16. Lithography, metrology and nanomanufacturing.

    Science.gov (United States)

    Liddle, J Alexander; Gallatin, Gregg M

    2011-07-01

    Semiconductor chip manufacturing is by far the predominant nanomanufacturing technology in the world today. Top-down lithography techniques are used for fabrication of logic and memory chips since, in order to function, these chips must essentially be perfect. Assuring perfection requires expensive metrology. Top of the line logic sells for several hundred thousand dollars per square metre and, even though the required metrology is expensive, it is a small percentage of the overall manufacturing cost. The level of stability and control afforded by current lithography tools means that much of this metrology can be online and statistical. In contrast, many of the novel types of nanomanufacturing currently being developed will produce products worth only a few dollars per square metre. To be cost effective, the required metrology must cost proportionately less. Fortunately many of these nanofabrication techniques, such as block copolymer self-assembly, colloidal self-assembly, DNA origami, roll-2-roll nano-imprint, etc., will not require the same level of perfection to meet specification. Given the variability of these self-assembly processes, in order to maintain process control, these techniques will require some level of real time online metrology. Hence we are led to the conclusion that future nanomanufacturing may well necessitate "cheap" nanometre scale metrology which functions real time and on-line, e.g. at GHz rates, in the production stream. In this paper we review top-down and bottom-up nanofabrication techniques and compare and contrast the various metrology requirements.

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

    Science.gov (United States)

    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.

  18. Low-loss and flatband silicon-nanowire-based 5th-order coupled resonator optical waveguides (CROW) fabricated by ArF-immersion lithography process on a 300-mm SOI wafer

    Science.gov (United States)

    Jeong, Seok-Hwan; Shimura, Daisuke; Simoyama, Takasi; Seki, Miyoshi; Yokoyama, Nobuyuki; Ohtsuka, Minoru; Koshino, Keiji; Horikawa, Tsuyoshi; Tanaka, Yu; Morito, Ken

    2014-03-01

    We present flatband, low-loss and low-crosstalk characteristics of Si-nanowire-based 5th-order coupled resonator optical waveguides (CROW) fabricated by ArF-immersion lithography process on a 300-mm silicon-on-insulator (SOI) wafer. We theoretically specified why phase controllability over Si-nanowire waveguides is prerequisite to attain desired spectral response, discussing spectral degradation by random phase errors during fabrication process. It was experimentally demonstrated that advanced patterning technology based on ArF-immersion lithography process showed extremely low phase errors even for Si-nanowire channel waveguides. As a result, the device exhibited extremely low loss of CROW. We believe these high-precision fabrication technologies based on 300-mm SOI wafer scale ArF-immersion lithography would be promising for several kinds of WDM multiplexers/demultiplexers having much complicated configurations and requiring much finer phase controllability.

  19. Chemistry and lithography

    CERN Document Server

    Okoroanyanwu, Uzodinma

    2011-01-01

    This is a unique book, combining chemistry and physics with technology and history in a way that is both enlightening and lively. No other book in the field of lithography has as much breadth. Highly recommended for anyone interested in the broad application of chemistry to lithography. --Chris Mack, Gentleman Scientist. This book provides a comprehensive treatment of the chemical phenomena in lithography in a manner that is accessible to a wide readership. The book presents topics on the optical and charged particle physics practiced in lithography, with a broader view of how the marriage bet

  20. On-Wire Lithography

    National Research Council Canada - National Science Library

    Lidong Qin; Sungho Park; Ling Huang; Chad A. Mirkin

    2005-01-01

    .... This procedure, termed on-wire lithography, combines advances in template-directed synthesis of nanowires with electrochemical deposition and wet-chemical etching and allows routine fabrication...

  1. Advances in Nanoimprint Lithography.

    Science.gov (United States)

    Traub, Matthew C; Longsine, Whitney; Truskett, Van N

    2016-06-07

    Nanoimprint lithography (NIL), a molding process, can replicate features <10 nm over large areas with long-range order. We describe the early development and fundamental principles underlying the two most commonly used types of NIL, thermal and UV, and contrast them with conventional photolithography methods used in the semiconductor industry. We then describe current advances toward full commercial industrialization of UV-curable NIL (UV-NIL) technology for integrated circuit production. We conclude with brief overviews of some emerging areas of research, from photonics to biotechnology, in which the ability of NIL to fabricate structures of arbitrary geometry is providing new paths for development. As with previous innovations, the increasing availability of tools and techniques from the semiconductor industry is poised to provide a path to bring these innovations from the lab to everyday life.

  2. Laser Interference Lithography

    NARCIS (Netherlands)

    van Wolferen, Hendricus A.G.M.; Abelmann, Leon; Hennessy, Theodore C.

    In this chapter we explain how submicron gratings can be prepared by Laser Interference Lithography (LIL). In this maskless lithography technique, the standing wave pattern that exists at the intersection of two coherent laser beams is used to expose a photosensitive layer. We show how to build the

  3. Arrays of holes fabricated by electron-beam lithography combined with image reversal process using nickel pulse reversal plating

    Science.gov (United States)

    Awad, Yousef; Lavallée, Eric; Lau, Kien Mun; Beauvais, Jacques; Drouin, Dominique; Cloutier, Melanie; Turcotte, David; Yang, Pan; Kelkar, Prasad

    2004-05-01

    A critical issue in fabricating arrays of holes is to achieve high-aspect-ratio structures. Formation of ordered arrays of nanoholes in silicon nitride was investigated by the use of ultrathin hard etch mask formed by nickel pulse reversal plating to invert the tonality of a dry e-beam resist patterned by e-beam lithography. Ni plating was carried out using a commercial plating solution based on nickel sulfamate salt without organic additives. Reactive ion etching using SF6/CH4 was found to be very effective for pattern transfer to silicon nitride. Holes array of 100 nm diam, 270 nm period, and 400 nm depth was fabricated on a 5×5 mm2 area. .

  4. Polymeric waveguide Bragg grating filter using soft lithography

    Science.gov (United States)

    Kocabas, Askin; Aydinli, Atilla

    2006-10-01

    We use the soft lithography technique to fabricate a polymeric waveguide Bragg grating filter. Master grating structure is patterned by e-beam lithography. Using an elastomeric stamp and capillary action, uniform grating structures with very thin residual layers are transferred to the UV curable polymer without the use of an imprint machine. The waveguide layer based on BCB optical polymer is fabricated by conventional optical lithography. This approach provides processing simplicity to fabricate Bragg grating filters.

  5. Ultrafast nanoimprint lithography (Invited Paper)

    Science.gov (United States)

    Xia, Qiangfei; Chou, Stephen Y.

    2005-04-01

    Both ultrafast thermal and photocurable nanoimprint lithography (NIL) are studied and high fidelity transfers of nanopatterns from molds to resists have been achieved. In ultrafast thermal NIL, we use a single excimer laser pulse to melt a NIL resist polymer and imprint it using a fused silica mold. The entire imprint process, from melting the polymer to completion of the imprint, takes less than 200 ns. This technique, termed laser assisted nanoimprint lithography (LAN), has patterned nanostructures in various polymer films with high fidelity over the entire mold area. In LAN, the short laser pulse is absorbed primarily by the resist and the laser energy is minute, hence substrate heating and distortion are negligible. In ultrafast photocurable NIL, a flash lamp (pulse width 94 μs) is used to crosslink photo curable resists over a 4 in. wafer with high uniformity by a single pulse. The significant reduction of the heating of the substrate and mold will greatly benefit overlay alignment.

  6. X-ray lithography source

    Science.gov (United States)

    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.

  7. Hollowing Process for StereoLithography Model%基于STL模型的抽壳方法研究

    Institute of Scientific and Technical Information of China (English)

    张征宇; 洪军; 丁玉成; 许瑞杰; 张敏华

    2004-01-01

    针对快速原型制造(RPM)和熔模铸造中对壳体原型的需求,提出了一种对零件的STL(STereoLithography)模型进行抽壳的新方法,将零件的STL模型的抽壳过程分解为沿Z坐标轴的偏置和切层轮廓区域偏置,并通过对偏置后的切层轮廓所围成的多边形进行布尔运算,得到了切层后零件的壳体STL模型.由于克服了STL模型三维偏置所面临的困难,因此特别适合对具有复杂曲面零件的STL模型进行抽壳.工程实例表明,该方法缩短了原型制作时间,降低了制作成本,具有实用价值和良好的市场前景.

  8. Lithography-based nanoelectrochemistry.

    Science.gov (United States)

    Rassaei, Liza; Singh, Pradyumna S; Lemay, Serge G

    2011-06-01

    Lithographically fabricated nanostructures appear in an increasingly wide range of scientific fields, and electroanalytical chemistry is no exception. This article introduces lithography methods and provides an overview of the new capabilities and electrochemical phenomena that can emerge in nanostructures.

  9. Polymer Pen Lithography

    National Research Council Canada - National Science Library

    Fengwei Huo; Zijian Zheng; Gengfeng Zheng; Louise R. Giam; Hua Zhang; Chad A. Mirkin

    2008-01-01

    We report a low-cost, high-throughput scanning probe lithography method that uses a soft elastomeric tip array, rather than tips mounted on individual cantilevers, to deliver inks to a surface in a “direct write” manner...

  10. A Novel Signal Processing Measure to Identify Exact and Inexact Tandem Repeat Patterns in DNA Sequences

    Directory of Open Access Journals (Sweden)

    Ravi Gupta

    2007-03-01

    Full Text Available The identification and analysis of repetitive patterns are active areas of biological and computational research. Tandem repeats in telomeres play a role in cancer and hypervariable trinucleotide tandem repeats are linked to over a dozen major neurodegenerative genetic disorders. In this paper, we present an algorithm to identify the exact and inexact repeat patterns in DNA sequences based on orthogonal exactly periodic subspace decomposition technique. Using the new measure our algorithm resolves the problems like whether the repeat pattern is of period P or its multiple (i.e., 2P, 3P, etc., and several other problems that were present in previous signal-processing-based algorithms. We present an efficient algorithm of O(NLw logLw, where N is the length of DNA sequence and Lw is the window length, for identifying repeats. The algorithm operates in two stages. In the first stage, each nucleotide is analyzed separately for periodicity, and in the second stage, the periodic information of each nucleotide is combined together to identify the tandem repeats. Datasets having exact and inexact repeats were taken up for the experimental purpose. The experimental result shows the effectiveness of the approach.

  11. A review of roll-to-roll nanoimprint lithography.

    Science.gov (United States)

    Kooy, Nazrin; Mohamed, Khairudin; Pin, Lee Tze; Guan, Ooi Su

    2014-01-01

    Since its introduction in 1995, nanoimprint lithography has been demonstrated in many researches as a simple, low-cost, and high-throughput process for replicating micro- and nanoscale patterns. Due to its advantages, the nanoimprint lithography method has been rapidly developed over the years as a promising alternative to conventional nanolithography processes to fulfill the demands generated from the recent developments in the semiconductor and flexible electronics industries, which results in variations of the process. Roll-to-roll (R2R) nanoimprint lithography (NIL) is the most demanded technique due to its high-throughput fulfilling industrial-scale application. In the present work, a general literature review on the various types of nanoimprint lithography processes especially R2R NIL and the methods commonly adapted to fabricate imprint molds are presented to provide a clear view and understanding on the nanoimprint lithography technique as well as its recent developments. 81.16.Nd.

  12. Data sharing system for lithography APC

    Science.gov (United States)

    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.

  13. Maskless, resistless ion beam lithography

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Qing [Univ. of California, Berkeley, CA (United States)

    2003-01-01

    process flow and the experimental results for directly patterned poly-Si features are presented. The formation of shallow pn-junctions in bulk silicon wafers by scanning focused P+ beam implantation at 5 keV is also presented. With implantation dose of around 1016 cm-2, the electron concentration is about 2.5 x 1018 cm-3 and electron mobility is around 200 cm2/V•s. To demonstrate the suitability of scanning FIB lithography for the manufacture of integrated circuit devices, SOI MOSFET fabrication using the maskless, resistless ion beam lithography is demonstrated. An array of microcolumns can be built by stacking multi-aperture electrode and insulator layers. Because the multicusp plasma source can achieve uniform ion density over a large area, it can be used in conjunction with the array of microcolumns, for massively parallel FIB processing to achieve reasonable exposure throughput.

  14. Maskless, resistless ion beam lithography

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Qing

    2003-03-10

    As the dimensions of semiconductor devices are scaled down, in order to achieve higher levels of integration, optical lithography will no longer be sufficient for the needs of the semiconductor industry. Alternative next-generation lithography (NGL) approaches, such as extreme ultra-violet (EUV), X-ray, electron-beam, and ion projection lithography face some challenging issues with complicated mask technology and low throughput. Among the four major alternative NGL approaches, ion beam lithography is the only one that can provide both maskless and resistless patterning. As such, it can potentially make nano-fabrication much simpler. This thesis investigates a focused ion beam system for maskless, resistless patterning that can be made practical for high-volume production. In order to achieve maskless, resistless patterning, the ion source must be able to produce a variety of ion species. The compact FIB system being developed uses a multicusp plasma ion source, which can generate ion beams of various elements, such as O{sub 2}{sup +}, BF{sub 2}{sup +}, P{sup +} etc., for surface modification and doping applications. With optimized source condition, around 85% of BF{sub 2}{sup +}, over 90% of O{sub 2}{sup +} and P{sup +} have been achieved. The brightness of the multicusp-plasma ion source is a key issue for its application to maskless ion beam lithography. It can be substantially improved by optimizing the source configuration and extractor geometry. Measured brightness of 2 keV He{sup +} beam is as high as 440 A/cm{sup 2} {center_dot} Sr, which represents a 30x improvement over prior work. Direct patterning of Si thin film using a focused O{sub 2}{sup +} ion beam has been investigated. A thin surface oxide film can be selectively formed using 3 keV O{sub 2}{sup +} ions with the dose of 10{sup 15} cm{sup -2}. The oxide can then serve as a hard mask for patterning of the Si film. The process flow and the experimental results for directly patterned poly-Si features

  15. Adaptive and repeated cumulative meta-analyses of safety data during a new drug development process.

    Science.gov (United States)

    Quan, Hui; Ma, Yingqiu; Zheng, Yan; Cho, Meehyung; Lorenzato, Christelle; Hecquet, Carole

    2015-01-01

    During a new drug development process, it is desirable to timely detect potential safety signals. For this purpose, repeated meta-analyses may be performed sequentially on accumulating safety data. Moreover, if the amount of safety data from the originally planned program is not enough to ensure adequate power to test a specific hypothesis (e.g., the noninferiority hypothesis of an event of interest), the total sample size may be increased by adding new studies to the program. Without appropriate adjustment, it is well known that the type I error rate will be inflated because of repeated analyses and sample size adjustment. In this paper, we discuss potential issues associated with adaptive and repeated cumulative meta-analyses of safety data conducted during a drug development process. We consider both frequentist and Bayesian approaches. A new drug development example is used to demonstrate the application of the methods.

  16. Joking Culture: The Role of Repeated Humorous Interactions on Group Processes during Challenge Course Experiences

    Science.gov (United States)

    Rothwell, Erin; Siharath, Kassidy; Bell, Steven; Nguyen, Kim; Baker, Carla

    2011-01-01

    When groups form, they develop their own culture from the shared meaning created from their interactions. Humor is part of every social group, and when repeatedly referenced, it forms a joking culture. The joking culture of small groups influences group processes by smoothing group interaction, forming a collective identity, separating the group…

  17. Design and Simulation of Symmetric Nanostructures Using Two-beam Modulated Interference Lithography Technique

    CERN Document Server

    Raj, A Alfred Kiruba; Devaprakasam, D

    2013-01-01

    Interferometry lithography is a maturing technology for patterning sub-micron structures in arrays covering large areas. This paper presents a method for the measurement of nanoscale surface patterns produced by two-beam laser interference lithography (LIL). The objective in this study is to simulate and design periodic and quasi-periodic 1D, 2D and 3D nanostructures using two-beam interference technique. We designed and simulated periodic and quasi-periodic structures by two-beam interference patterning using a MATLAB program by varying angle of incidence, wavelength and geometry. The simulated patterns show that the symmetries of the interference maxima depend mostly on the angles of incidence and perturbations of incidents beams. Using this technique, we can achieve potentially high-volume of uniformity, throughput, process control, and repeatability. By varying different input parameters, we have optimized simulated patterns with controlled periodicity, density and aspect ratio also it can be programmed t...

  18. Principles of lithography

    CERN Document Server

    Levinson, Harry J

    2011-01-01

    The publication of Principles of Lithography, Third Edition just five years after the previous edition is evidence of the quickly changing and exciting nature of lithography as applied to the production of integrated circuits and other micro- and nanoscale devices. This text is intended to serve as an introduction to the science of microlithography, but also covers several subjects in depth, making it useful to the experienced lithographer as well. Topics directly related to manufacturing tools are addressed, including overlay, the stages of exposure, tools, and light sources. This updated edi

  19. Electron caustic lithography

    Directory of Open Access Journals (Sweden)

    S. M. Kennedy

    2012-06-01

    Full Text Available A maskless method of electron beam lithography is described which uses the reflection of an electron beam from an electrostatic mirror to produce caustics in the demagnified image projected onto a resist–coated wafer. By varying the electron optics, e.g. via objective lens defocus, both the morphology and dimensions of the caustic features may be controlled, producing a range of bright and tightly focused projected features. The method is illustrated for line and fold caustics and is complementary to other methods of reflective electron beam lithography.

  20. Cost of ownership for future lithography technologies

    Science.gov (United States)

    Hazelton, Andrew J.; Wüest, Andrea; Hughes, Greg; Litt, Lloyd C.; Goodwin, Frank

    2008-11-01

    The cost of ownership (COO) of candidate technologies for 32 nm and 22 nm half-pitch lithography is calculated. To more accurately compare technologies with different numbers of process steps, a model that includes deposition, etching, metrology, and other costs is created. Results show lithography COO for leading edge layers will increase by roughly 50% from the 45 nm to the 32 nm half-pitch nodes. Double patterning and extreme ultraviolet lithography (EUVL) technologies have roughly the same COO under certain conditions. For 22 nm half-pitch nodes, EUVL has a significant cost advantage over other technologies under certain mask cost assumptions. Double patterning, however, may be competitive under worst case EUVL mask cost assumptions. Sensitivity studies of EUVL COO to throughput and uptime show EUVL may be cost-competitive at lower uptime and throughput conditions. In spite of these higher costs, total lithography costs for 32 nm and 22 nm half-pitches remain within reach of the Moore's Law trend. Finally, the COO of 450 mm lithography is calculated and shows the expected cost reduction is between 0% and 15%.

  1. Flexible Stamp for Nanoimprint Lithography

    DEFF Research Database (Denmark)

    Nielsen, Theodor; Pedersen, Rasmus H.; Hansen, Ole

    2005-01-01

    The design, fabrication and performance of a flexible silicon stamp for homogenous large area nanoimprint lithography (NIL) are presented. The flexible stamp is fabricated by bulk semiconductor micro machining of a 4-inch silicon wafer and consists of thick anchor like imprint areas connected...... by membranes. The bending stiffness difference between the imprint areas and the membranes ensures that the deformation of the stamp during the imprint process mainly takes place in the membranes, leaving the imprint structures unaffected. By this design the strong demand to the parallelism between stamp...

  2. Comparison of measurement methods for microsystem components: application to microstructures made by the deep x-ray lithography process (x-ray LIGA)

    Science.gov (United States)

    Meyer, Pascal; Mäder, Olaf; Saile, Volker; Schulz, Joachim

    2009-08-01

    The LIGA (a German acronym for lithography, electroplating and molding) process using highly parallel x-rays permits the production of a microstructure with still unique characteristics: high aspect ratio, high accuracy, high perpendicularity and lower roughness of the side wall. From a marketing point of view, this qualitative description might suffice to attract users to the technology. Regarding widespread commercialization and standardization of x-ray LIGA products, our goal is to establish a rigorous dimensional metrology for which we need to understand and quantify uncertainty, which is the key to accuracy. We report on our metrological study using a coordinate measurement machine (CMM) equipped with a fibre probe (3D measurements) which will be compared to two versions of lateral top-view measurements (2D/surface measurements): an optical microscope provided with a micrometric table and a CMM with an image processing sensor; these two types of measurement methods being complementary. In fact, microsystem technology requires measurements to be performed with precision and accuracy within the range of 0.1 µm. In this paper, we present an analysis and a discussion of both types of measurement systems. The precision and reproducibility of the CMM (with fibre probe) during a two-year study will be exposed; a calibrated series part is being measured every time the machine is used. In this case, the CMM is used as a comparator. Its accuracy and the calibration of the ball diameter using an etalon (ceramic gage block) will be exposed. Furthermore, by taking into account the results obtained by the measurement system analysis (MSA), we will show the measurement's impact on the process by taking as an example the fabrication of mm gold gears for watch industry; a quantitative description of process reproducibility and of the influence of processing parameters influence will be possible in the future.

  3. Monte Carlo electron beam lithography simulation of sub-0.1-mum T-gate process for millimeter-wave HEMTs considering 50-kV and 100-kV electron beam exposure systems

    Energy Technology Data Exchange (ETDEWEB)

    Son, Myung-Sik; Rhee, Jin-Koo [Dongguk University, Seoul (Korea, Republic of); Lee, Jun-Ha [Sangmyung University, Chonan (Korea, Republic of); Hwang, Ho-Jung [Chung-Ang University, Seoul (Korea, Republic of)

    2004-08-15

    A computationally efficient and accurate Monte Carlo (MC) simulator for electron beam lithography has been developed and applied for the sub-0.1-mum T-shaped gate (T-gate) process in HEMT devices for the millimeter-wave applications. The enhanced MC simulator for the electron trajectory includes elastic scattering and inelastic scatterings, which include inner-shell ionizations, outer-shell (free) excitations, and plasmon excitations in multi-layer resists and heterogeneous substrates. Our model has been applied to the structure of PMMA/P(MMA-MAA)/PMMA on a GaAs substrate to form the T-gate shape in resist layers. We considered and modeled a real fabrication process, such as the electron-beam double-exposure method, to obtain better reproducibility and controllability in the fabrication of high electron mobility transistor (HEMT) devices. To model an accurate T-gate process by using electron beam lithography, we have modeled three different developers using a string algorithm such as MCB, Methanol : IPA (1 : 1), and MIBK : IPA (1 : 3). Our simulations for the T-gate electron beam lithography have been verified by comparing them with the SEM measurements at a 50-keV electron beam exposure system. In this paper, we show and discuss the differences of exposure profiles and developed pattern shapes for the sub-0.1-mum T-gate formation process in trilayer resists using 50-kV and 100-kV electron beam exposure systems.

  4. Optical lithography at a 126-nm wavelength

    Science.gov (United States)

    Kang, Hoyoung; Bourov, Anatoly; Smith, Bruce W.

    2001-08-01

    There is a window of opportunity for optical lithography between wavelengths of 100 nm and 157 nm that warrants exploration as a next generation technology. We will present activities underway to explore the feasibility of VUV optical lithography in this region with respect to source, optical design, materials, processes, masks, resolution enhancement, and compatibility with existing technologies. We have constructed a small field prototype lithography system using the second continuum 126nm emission wavelength of the Argon excimer. This has been accomplished using a small dielectric barrier discharge lamp with output on the order of 10mW/cm2 and small field catoptric imaging systems based on a modified Cassegrain system. Capacitance focus gauge and piezo electric stage has been installed for fine focusing. In order to achieve sub-half wavelength resolution that would be required to compete with 157nm lithography and others, we have started exploring the feasibility of using liquefied noble gas immersion fluids to increase effective value of lens numerical aperture by factors approaching 1.4x. Conventional silylation process works well with 126nm with high sensitivity. Chemically amplified DUV negative resist looks very good material for 126 nm. Initial contact printing image shows good selectivity and process control. An effort is also underway to explore the use of inorganic resist materials, as silver halide material for instance, to replace the conventional polymeric imaging systems that are currently employed at longer wavelengths, but may be problematic at these VUV wavelengths. Early accomplishments are encouraging. Prototype optical research tools can be used to reveal issues involved with 126nm lithography and solve initial problems. Though many challenges do exist at this short wavelength, it is quite feasible that lithography at this wavelength could meet the part of the needs of future device generations.

  5. High-Speed Digital Signal Processing Method for Detection of Repeating Earthquakes Using GPGPU-Acceleration

    Science.gov (United States)

    Kawakami, Taiki; Okubo, Kan; Uchida, Naoki; Takeuchi, Nobunao; Matsuzawa, Toru

    2013-04-01

    Repeating earthquakes are occurring on the similar asperity at the plate boundary. These earthquakes have an important property; the seismic waveforms observed at the identical observation site are very similar regardless of their occurrence time. The slip histories of repeating earthquakes could reveal the existence of asperities: The Analysis of repeating earthquakes can detect the characteristics of the asperities and realize the temporal and spatial monitoring of the slip in the plate boundary. Moreover, we are expecting the medium-term predictions of earthquake at the plate boundary by means of analysis of repeating earthquakes. Although the previous works mostly clarified the existence of asperity and repeating earthquake, and relationship between asperity and quasi-static slip area, the stable and robust method for automatic detection of repeating earthquakes has not been established yet. Furthermore, in order to process the enormous data (so-called big data) the speedup of the signal processing is an important issue. Recently, GPU (Graphic Processing Unit) is used as an acceleration tool for the signal processing in various study fields. This movement is called GPGPU (General Purpose computing on GPUs). In the last few years the performance of GPU keeps on improving rapidly. That is, a PC (personal computer) with GPUs might be a personal supercomputer. GPU computing gives us the high-performance computing environment at a lower cost than before. Therefore, the use of GPUs contributes to a significant reduction of the execution time in signal processing of the huge seismic data. In this study, first, we applied the band-limited Fourier phase correlation as a fast method of detecting repeating earthquake. This method utilizes only band-limited phase information and yields the correlation values between two seismic signals. Secondly, we employ coherence function using three orthogonal components (East-West, North-South, and Up-Down) of seismic data as a

  6. Nanobiotechnology: soft lithography.

    Science.gov (United States)

    Mele, Elisa; Pisignano, Dario

    2009-01-01

    An entirely new scientific and technological area has been born from the combination of nanotechnology and biology: nanobiotechnology. Such a field is primed especially by the strong potential synergy enabled by the integration of technologies, protocols, and investigation methods, since, while biomolecules represent functional nanosystems interesting for nanotechnology, micro- and nano-devices can be very useful instruments for studying biological materials. In particular, the research of new approaches for manipulating matter and fabricating structures with micrometre- and sub-micrometre resolution has determined the development of soft lithography, a new set of non-photolithographic patterning techniques applied to the realization of selective proteins and cells attachment, microfluidic circuits for protein and DNA chips, and 3D scaffolds for tissue engineering. Today, soft lithographies have become an asset of nanobiotechnology. This Chapter examines the biological applications of various soft lithographic techniques, with particular attention to the main general features of soft lithography and of materials commonly employed with these methods. We present approaches particularly suitable for biological materials, such as microcontact printing (muCP) and microfluidic lithography, and some key micro- and nanobiotechnology applications, such as the patterning of protein and DNA microarrays and the realization of microfluidic-based analytical devices.

  7. An ice lithography instrument

    Science.gov (United States)

    Han, Anpan; Chervinsky, John; Branton, Daniel; Golovchenko, J. A.

    2011-06-01

    We describe the design of an instrument that can fully implement a new nanopatterning method called ice lithography, where ice is used as the resist. Water vapor is introduced into a scanning electron microscope (SEM) vacuum chamber above a sample cooled down to 110 K. The vapor condenses, covering the sample with an amorphous layer of ice. To form a lift-off mask, ice is removed by the SEM electron beam (e-beam) guided by an e-beam lithography system. Without breaking vacuum, the sample with the ice mask is then transferred into a metal deposition chamber where metals are deposited by sputtering. The cold sample is then unloaded from the vacuum system and immersed in isopropanol at room temperature. As the ice melts, metal deposited on the ice disperses while the metals deposited on the sample where the ice had been removed by the e-beam remains. The instrument combines a high beam-current thermal field emission SEM fitted with an e-beam lithography system, cryogenic systems, and a high vacuum metal deposition system in a design that optimizes ice lithography for high throughput nanodevice fabrication. The nanoscale capability of the instrument is demonstrated with the fabrication of nanoscale metal lines.

  8. Ice Lithography for Nanodevices

    DEFF Research Database (Denmark)

    Han, Anpan; Kuan, A.; Wang, J.

    Water vapor is condensed onto a cold sample, coating it with a thin-film of ice. The ice is sensitive to electron beam lithography exposure. 10 nm ice patterns are transferred into metals by “melt-off”. Non-planar samples are coated with ice, and we pattern on cantilevers, AFM tips, and suspended...

  9. Neutral particle lithography

    Science.gov (United States)

    Craver, Barry Paul

    Neutral particle lithography (NPL) is a high resolution, proximity exposure technique where a broad beam of energetic neutral particles floods a stencil mask and transmitted beamlets transfer the mask pattern to resist on a substrate, such that each feature is printed in parallel, rather than in the serial manner of electron beam lithography. It preserves the advantages of ion beam lithography (IBL), including extremely large depth-of-field, sub-5 nm resist scattering, and the near absence of diffraction, yet is intrinsically immune to charge-related artifacts including line-edge roughness and pattern placement errors due to charge accumulation on the mask and substrate. In our experiments, a neutral particle beam is formed by passing an ion beam (e.g., 30 keV He+) through a high pressure helium gas cell (e.g., 100 mTorr) to convert the ions to energetic neutrals through charge transfer scattering. The resolution of NPL is generally superior to that of IBL for applications involving insulating substrates, large proximity gaps, and ultra-small features. High accuracy stepped exposures with energetic neutral particles, where magnetic or electrostatic deflection is impossible, have been obtained by clamping the mask to the wafer, setting the proximity gap with a suitable spacer, and mechanically inclining the mask/wafer stack relative to the beam. This approach is remarkably insensitive to vibration and thermal drift; nanometer scale image offsets have been obtained with +/-2 nm placement accuracy for experiments lasting over one hour. Using this nanostepping technique, linewidth versus dose curves were obtained, from which the NPL lithographic blur was determined as 4.4+/-1.4 nm (1sigma), which is 2-3 times smaller than the blur of electron beam lithography. Neutral particle lithography has the potential to form high density, periodic patterns with sub-10 nm resolution.

  10. Consolidation effect of repeated processing of declarative knowledge in mental experiences during human sleep.

    Science.gov (United States)

    Cipolli, Carlo; Fagioli, Igino; Mazzetti, Michela; Tuozzi, Giovanni

    2006-05-15

    Sleep may positively influence declarative memory through the processing, which transforms items of declarative knowledge into contents of mental sleep experience (MSE). A prediction from this general hypothesis is that the consolidation level should be higher for the output of items repeatedly processed and transformed into identical or very similar (so-called interrelated) contents of distinct MSEs of the same night rather than for the output of items presumably processed once (that is, all other, non-interrelated contents). Two experiments examined whether and how far the frequency and long-term retention of interrelated contents depend on the repeated processing of given items rather than on the experimental procedure applied for detection of interrelated contents. This procedure entails both multiple awakenings and a verbal report of MSE after awakening. Multiple awakenings could facilitate the re-access and elaboration of some contents into the subsequent (i.e. contiguous) MSE rather than non-contiguous MSEs; verbal reports could enhance the delayed recall of interrelated contents in as much as repeatedly encoded. The first experiment showed that interrelated contents were more frequent and better retained than both non-interrelated and pseudo-interrelated (i.e. by-chance similar or identical) contents, and even more in pairs of contiguous than non-contiguous MSEs collected from the first four periods of REM sleep on each experimental night. The second experiment showed that the frequency and retention rate of interrelated contents, while higher than those of non-interrelated and pseudo-interrelated contents, were not significantly different in pairs of MSEs which were verbally or mentally recalled after awakening provoked during the first four periods of REM sleep in each experimental night. Taken together, these findings indicate that the advantage provided by repeated processing during REM sleep for the consolidation of the output of items of declarative

  11. Athermal Azobenzene-Based Nanoimprint Lithography.

    Science.gov (United States)

    Probst, Christian; Meichner, Christoph; Kreger, Klaus; Kador, Lothar; Neuber, Christian; Schmidt, Hans-Werner

    2016-04-06

    A novel nanoimprint lithography technique based on the photofluidization effect of azobenzene materials is presented. The tunable process allows for imprinting under ambient conditions without crosslinking reactions, so that shrinkage of the resist is avoided. Patterning of surfaces in the regime from micrometers down to 100 nm is demonstrated. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Modelling and Experimental Evaluation of (Post)Lithography Process Contributions to Pattern Roughness (Modellering en experimentele evaluatie van (post)-lithografie procesbijdragen aan patroon ruwheid)

    OpenAIRE

    2012-01-01

    Extreme UV lithography is the leading top-down patterning technology for the development of semiconductor products beyond the traditional optica l lithography. It uses a Tin-based plasma to create photons at a wavelen gth of 13.5 nm, an under vacuum reflective optical system (photomask inc luded)based on multilayers mirrors, and a highly absorbing photoresist t o create the desired pattern. Started in 1980, much progress has been made in order to drive this tech nology to the level of maturit...

  13. Development of ballistic hot electron emitter and its applications to parallel processing: active-matrix massive direct-write lithography in vacuum and thin films deposition in solutions

    Science.gov (United States)

    Koshida, N.; Kojima, A.; Ikegami, N.; Suda, R.; Yagi, M.; Shirakashi, J.; Yoshida, T.; Miyaguchi, H.; Muroyama, M.; Nishino, H.; Yoshida, S.; Sugata, M.; Totsu, K.; Esashi, M.

    2015-03-01

    Making the best use of the characteristic features in nanocrystalline Si (nc-Si) ballistic hot electron source, the alternative lithographic technology is presented based on the two approaches: physical excitation in vacuum and chemical reduction in solutions. The nc-Si cold cathode is a kind of metal-insulator-semiconductor (MIS) diode, composed of a thin metal film, an nc-Si layer, an n+-Si substrate, and an ohmic back contact. Under a biased condition, energetic electrons are uniformly and directionally emitted through the thin surface electrodes. In vacuum, this emitter is available for active-matrix drive massive parallel lithography. Arrayed 100×100 emitters (each size: 10×10 μm2, pitch: 100 μm) are fabricated on silicon substrate by conventional planar process, and then every emitter is bonded with integrated complementary metal-oxide-semiconductor (CMOS) driver using through-silicon-via (TSV) interconnect technology. Electron multi-beams emitted from selected devices are focused by a micro-electro-mechanical system (MEMS) condenser lens array and introduced into an accelerating system with a demagnification factor of 100. The electron accelerating voltage is 5 kV. The designed size of each beam landing on the target is 10×10 nm2 in square. Here we discuss the fabrication process of the emitter array with TSV holes, implementation of integrated ctive-matrix driver circuit, the bonding of these components, the construction of electron optics, and the overall operation in the exposure system including the correction of possible aberrations. The experimental results of this mask-less parallel pattern transfer are shown in terms of simple 1:1 projection and parallel lithography under an active-matrix drive scheme. Another application is the use of this emitter as an active electrode supplying highly reducing electrons into solutions. A very small amount of metal-salt solutions is dripped onto the nc-Si emitter surface, and the emitter is driven without

  14. Metal-mesh lithography.

    Science.gov (United States)

    Tang, Zhao; Wei, Qingshan; Wei, Alexander

    2011-12-01

    Metal-mesh lithography (MML) is a practical hybrid of microcontact printing and capillary force lithography that can be applied over millimeter-sized areas with a high level of uniformity. MML can be achieved by blotting various inks onto substrates through thin copper grids, relying on preferential wetting and capillary interactions between template and substrate for pattern replication. The resulting mesh patterns, which are inverted relative to those produced by stenciling or serigraphy, can be reproduced with low micrometer resolution. MML can be combined with other surface chemistry and lift-off methods to create functional microarrays for diverse applications, such as periodic islands of gold nanorods and patterned corrals for fibroblast cell cultures.

  15. Msh2-Msh3 Interferes with Okazaki Fragment Processing to Promote Trinucleotide Repeat Expansions

    Directory of Open Access Journals (Sweden)

    Athena Kantartzis

    2012-08-01

    Full Text Available Trinucleotide repeat (TNR expansions are the underlying cause of more than 40 neurodegenerative and neuromuscular diseases, including myotonic dystrophy and Huntington’s disease. Although genetic evidence points to errors in DNA replication and/or repair as the cause of these diseases, clear molecular mechanisms have not been described. Here, we focused on the role of the mismatch repair complex Msh2-Msh3 in promoting TNR expansions. We demonstrate that Msh2-Msh3 promotes CTG and CAG repeat expansions in vivo in Saccharomyces cerevisiae. Furthermore, we provide biochemical evidence that Msh2-Msh3 directly interferes with normal Okazaki fragment processing by flap endonuclease1 (Rad27 and DNA ligase I (Cdc9 in the presence of TNR sequences, thereby producing small, incremental expansion events. We believe that this is the first mechanistic evidence showing the interplay of replication and repair proteins in the expansion of sequences during lagging-strand DNA replication.

  16. Extreme ultraviolet Talbot interference lithography.

    Science.gov (United States)

    Li, Wei; Marconi, Mario C

    2015-10-05

    Periodic nanopatterns can be generated using lithography based on the Talbot effect or optical interference. However, these techniques have restrictions that limit their performance. High resolution Talbot lithography is limited by the very small depth of focus and the demanding requirements in the fabrication of the master mask. Interference lithography, with large DOF and high resolution, is limited to simple periodic patterns. This paper describes a hybrid extreme ultraviolet lithography approach that combines Talbot lithography and interference lithography to render an interference pattern with a lattice determined by a Talbot image. As a result, the method enables filling the arbitrary shaped cells produced by the Talbot image with interference patterns. Detailed modeling, system design and experimental results using a tabletop EUV laser are presented.

  17. Geomorphic process from topographic form: automating the interpretation of repeat survey data in river valleys

    Science.gov (United States)

    Kasprak, Alan; Caster, Joshua J.; Bangen, Sara G.; Sankey, Joel B.

    2017-01-01

    The ability to quantify the processes driving geomorphic change in river valley margins is vital to geomorphologists seeking to understand the relative role of transport mechanisms (e.g. fluvial, aeolian, and hillslope processes) in landscape dynamics. High-resolution, repeat topographic data are becoming readily available to geomorphologists. By contrasting digital elevation models derived from repeat surveys, the transport processes driving topographic changes can be inferred, a method termed ‘mechanistic segregation.’ Unfortunately, mechanistic segregation largely relies on subjective and time consuming manual classification, which has implications both for its reproducibility and the practical scale of its application. Here we present a novel computational workflow for the mechanistic segregation of geomorphic transport processes in geospatial datasets. We apply the workflow to seven sites along the Colorado River in the Grand Canyon, where geomorphic transport is driven by a diverse suite of mechanisms. The workflow performs well when compared to field observations, with an overall predictive accuracy of 84% across 113 validation points. The approach most accurately predicts changes due to fluvial processes (100% accuracy) and aeolian processes (96%), with reduced accuracy in predictions of alluvial and colluvial processes (64% and 73%, respectively). Our workflow is designed to be applicable to a diversity of river systems and will likely provide a rapid and objective understanding of the processes driving geomorphic change at the reach and network scales. We anticipate that such an understanding will allow insight into the response of geomorphic transport processes to external forcings, such as shifts in climate, land use, or river regulation, with implications for process-based river management and restoration.

  18. Tuning the phase transition of ZnO thin films through lithography: an integrated bottom-up and top-down processing.

    Science.gov (United States)

    Malfatti, Luca; Pinna, Alessandra; Enzo, Stefano; Falcaro, Paolo; Marmiroli, Benedetta; Innocenzi, Plinio

    2015-01-01

    An innovative approach towards the physico-chemical tailoring of zinc oxide thin films is reported. The films have been deposited by liquid phase using the sol-gel method and then exposed to hard X-rays, provided by a synchrotron storage ring, for lithography. The use of surfactant and chelating agents in the sol allows easy-to-pattern films made by an organic-inorganic matrix to be deposited. The exposure to hard X-rays strongly affects the nucleation and growth of crystalline ZnO, triggering the formation of two intermediate phases before obtaining a wurtzite-like structure. At the same time, X-ray lithography allows for a fast patterning of the coatings enabling microfabrication for sensing and arrays technology.

  19. Soft lithography contacts to organics

    Directory of Open Access Journals (Sweden)

    Julia W.P. Hsu

    2005-07-01

    Full Text Available Organic materials play an increasingly important role in (optoelectronics, particularly in low-cost or flexible devices. A major challenge is the contact between the electrodes and the organic material. Processes developed for inorganic semiconductors are inapplicable because of the sensitivity of organic materials to heat, radiation, and chemicals. Deposition of metal(s through shadow masks onto organic materials is commonly used, despite problems with ill-controlled interfaces and material damage. In addition, conventional approaches restrict device size to >1 μm. Clearly, a better technique is needed. In this article, two soft lithography methods for making contacts to organic materials are reviewed: nanotransfer printing (nTP and soft-contact lamination (ScL. These new approaches produce devices that outperform those made by conventional methods. The link between better device performance and better interfacial control is explained, and nanoscale devices are described.

  20. Mapper: high troughput maskless lithography

    NARCIS (Netherlands)

    Slot, E.; Wieland, M.J.; de Boer, G.; Kruit, P.; Ten Berge, G.F.; Houkes, A.M.C.; Jager, R.; Van de Peut, T.; Peijster, J.J.M.; Steenbrink, S.W.H.K.

    2008-01-01

    MAPPER Lithography is developing a maskless lithography technology. The technology combines massively-parallel electron-beam writing with high speed optical data transport used in the telecommunication industry. The electron optics generates 13,000 electron beams that are focused on the wafer by

  1. Colloidal pen lithography.

    Science.gov (United States)

    Xue, Mianqi; Cai, Xiaojing; Chen, Ghenfu

    2015-02-04

    Colloidal pen lithography, a low-cost, high-throughput scanning probe contact printing method, has been developed, which is based on self-assembled colloidal arrays embedded in a soft elastomeric stamp. Patterned protein arrays are demonstrated using this method, with a feature size ranging from 100 nm to several micrometers. A brief study into the specificity reorganization of protein gives evidence for the feasibility of this method for writing protein chips. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Direct-write scanning probe lithography: towards a desktop fab

    Science.gov (United States)

    Giam, Louise R.; Senesi, Andrew J.; Liao, Xing; Wong, Lu Shin; Chai, Jinan; Eichelsdoerfer, Daniel J.; Shim, Wooyoung; Rasin, Boris; He, Shu; Mirkin, Chad A.

    2011-06-01

    Massively parallel scanning-probe based methods have been used to address the challenges of nanometer to millimeter scale printing for a variety of materials and mark a step towards the realization of a "desktop fab." Such tools enable simple, flexible, high-throughput, and low-cost nano- and microscale patterning, which allow researchers to rapidly synthesize and study systems ranging from nanoparticle synthesis to biological processes. We have developed a novel scanning probe-based cantilever-free printing method termed polymer pen lithography (PPL), which uses an array of elastomeric tips to transfer materials (e.g. alkanethiols, proteins, polymers) in a direct-write manner onto a variety of surfaces. This technique takes the best attributes of dip-pen nanolithography (DPN) and eliminates many of the disadvantages of contact printing. Various related techniques such as beam pen lithography (BPL), scanning probe block copolymer lithography (SPBCL), and hard-tip, soft spring lithography (HSL) are also discussed.

  3. Development of motorized plasma lithography for cell patterning.

    Science.gov (United States)

    Deguchi, Shinji; Nagasawa, Yohei; Saito, Akira C; Matsui, Tsubasa S; Yokoyama, Sho; Sato, Masaaki

    2014-03-01

    The micropatterning of cells, which restricts the adhesive regions on the substrate and thus controls cell geometry, is used to study mechanobiology-related cell functions. Plasma lithography is a means of providing such patterns and uses a spatially-selective plasma treatment. Conventional plasma lithography employs a positionally-fixed mask with which the geometry of the patterns is determined and thus is not suited for producing on-demand geometries of patterns. To overcome this, we have manufactured a new device with a motorized mask mounted in a vacuum chamber of a plasma generator, which we designate motorized plasma lithography. Our pilot tests indicate that various pattern geometries can be obtained with the control of a shielding mask during plasma treatment. Our approach can thus omit the laborious process of preparing photolithographically microfabricated masks required for the conventional plasma lithography.

  4. Hyper-lithography

    CERN Document Server

    Sun, Jingbo; Litchinitser, Natalia M

    2016-01-01

    The future success of integrated circuits (IC) technology relies on the continuing miniaturization of the feature size, allowing more components per chip and higher speed. Extreme anisotropy opens new opportunities for spatial pattern compression from the micro- to nano-scale. Such compression, enabling visible light-based lithographic patterning not restricted by the fundamental diffraction limit,if realized,may address the ever-increasing demand of IC industry for inexpensive, all-optical nanoscale lithography. By exploiting strongly anisotropic optical properties of engineered nanostructures, we realize the first experimental demonstration of hyperlens-based photolithography, facilitating optical patterning below the diffraction limit using a diffraction-limited mask. We demonstrate that the diffraction-limited features on a mask can be de-magnified to form the subwavelength patterns on the photoresist using visible light. This unique functionality,enabled by the hyperbolic dispersive properties of the med...

  5. Method for maskless lithography

    Science.gov (United States)

    Sweatt, William C.; Stulen, Richard H.

    2000-01-01

    The present invention provides a method for maskless lithography. A plurality of individually addressable and rotatable micromirrors together comprise a two-dimensional array of micromirrors. Each micromirror in the two-dimensional array can be envisioned as an individually addressable element in the picture that comprises the circuit pattern desired. As each micromirror is addressed it rotates so as to reflect light from a light source onto a portion of the photoresist coated wafer thereby forming a pixel within the circuit pattern. By electronically addressing a two-dimensional array of these micromirrors in the proper sequence a circuit pattern that is comprised of these individual pixels can be constructed on a microchip. The reflecting surface of the micromirror is configured in such a way as to overcome coherence and diffraction effects in order to produce circuit elements having straight sides.

  6. Surface enhanced thermo lithography

    KAUST Repository

    Coluccio, Maria Laura

    2017-01-13

    We used electroless deposition to fabricate clusters of silver nanoparticles (NPs) on a silicon substrate. These clusters are plasmonics devices that induce giant electromagnetic (EM) field increments. When those EM field are absorbed by the metal NPs clusters generate, in turn, severe temperature increases. Here, we used the laser radiation of a conventional Raman set-up to transfer geometrical patterns from a template of metal NPs clusters into a layer of thermo sensitive Polyphthalaldehyde (PPA) polymer. Temperature profile on the devices depends on specific arrangements of silver nanoparticles. In plane temperature variations may be controlled with (i) high nano-meter spatial precision and (ii) single Kelvin temperature resolution on varying the shape, size and spacing of metal nanostructures. This scheme can be used to generate strongly localized heat amplifications for applications in nanotechnology, surface enhanced thermo-lithography (SETL), biology and medicine (for space resolved cell ablation and treatment), nano-chemistry.

  7. Photoresists in extreme ultraviolet lithography (EUVL)

    Science.gov (United States)

    De Simone, Danilo; Vesters, Yannick; Vandenberghe, Geert

    2017-06-01

    The evolutionary advances in photosensitive material technology, together with the shortening of the exposure wavelength in the photolithography process, have enabled and driven the transistor scaling dictated by Moore's law for the last 50 years. Today, the shortening wavelength trend continues to improve the chips' performance over time by feature size miniaturization. The next-generation lithography technology for high-volume manufacturing (HVM) is extreme ultraviolet lithography (EUVL), using a light source with a wavelength of 13.5 nm. Here, we provide a brief introduction to EUVL and patterning requirements for sub-0-nm feature sizes from a photomaterial standpoint, discussing traditional and novel photoresists. Emphasis will be put on the novel class of metal-containing resists (MCRs) as well as their challenges from a manufacturing prospective.

  8. Stochastic simulation studies of line-edge roughness in block copolymer lithography.

    Science.gov (United States)

    Kim, Sang-Kon

    2014-08-01

    Because photoresist has the uncertain triangle relation among the higher resolution, the lower line-edge-roughness (LER) (or line-with-roughness (LWR)), and the improved sensitivity, for below 20-nm pattern formation, this relation makes hard to use the optical lithography. Directed self-assembly (DSA) has been considered as a potential candidate to extend the resolution limit of the optical lithography. The effects of DSA processing and DSA molecular geometry on LER should be well understood in order to meet the ITRS lithographic specifications. In this paper, for the optical lithography and the block copolymer (BCP) lithography such as graphoepitaxy, LER behavior is modeled by the stochastic methods such as the Monte Carlo method and the dissipative particle dynamics (DPD) method. Simulation results explain that the LER of the BCP lithography is smaller than that of the optical lithography because of a self-healing capability of block copolymers.

  9. High-contrast process using a positive-tone resist with antistatic coating and high-energy (100-keV) e-beam lithography for fabricating diffractive optical elements (DOE) on quartz

    Science.gov (United States)

    Poli, Louis C.; Kondek, Christine A.; Shoop, Barry L.; McLane, George F.

    1995-06-01

    Diffractive optical elements (DOE) are becoming important as optical signal processing elements in increasingly diverse applications. These elements, fabricated on quartz, may be used as phase shift type masks or as embedded components that implement a transfer function within a processing network. A process is under development for the fabrication of a DOE implementing a Jervis error diffusion kernel for research in half tone image processing. Dry etching is performed after lithography and pattern transfer through a nickel mask. This results in etched areal features on the substrate. An optical diffraction medium is thus created. Lithographic patterning is done by e-beam lithography (EBL) to realize small features, but also offers the important advantage of a large depth of field which relaxes the problem of complex surface topology. The recent availability of high energy (100 KeV) lithography tools provides a capability for precision overlay, small feature resolution, and enhanced image contrast through a lower induced proximity effect. Patterning by EBL on insulating substrates is complicated by the necessity of providing a vehicle for the avoidance of charge buildup on the surface. In a previously presented paper a methodology was shown for the use of TQV-501 (Nitto Chemical) antistatic compound as a final spin on film for use with PMMA and SAL-601 (Shipley). In this current work, a process is described using EBL and a high performance positive resist working with a final film layer of antistatic TQV-501 on a nickel coated wafer. The process may then be reapplied to realize additional lithographic levels in registration, for multilevel DOE components. High energy (100 KeV) EBL is used to provide high quality pattern definition. The e-beam sensitive resist, ZEP-320-37 (Nagase Chemical) in dilution, together with a top film layer of TQV-501 serves as a bilevel resist system and is used for patterning the desired image before definition of the nickel mask through

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

    Science.gov (United States)

    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

  11. Repeat-pass InSAR processing for Vegetation Height Calculation: Theory and a validated example

    Science.gov (United States)

    Siqueira, P.; Lei, Y.

    2014-12-01

    Knowledge of the vegetation height for a forested region is often used as a proxy for stem volume, biomass, and for characterizing habitats of a variety of plant and animal species. For this reason, remote sensing measures available from stereography, lidar, and InSAR have been important tools for airborne and spaceborne platforms. Among these and other candidates for measuring vegetation heights, InSAR has the advantage of achieving wide coverage areas (on the order of 100 km in cross-track swath) over short time periods, thus making it practical for large-scale assessments of the global environment. The determination of forest stand height (FSH), which is an assessment made on the order of one to ten hectares of resolution, InSAR can provide measures that are proportional to FSH. These are: 1.) interferometric phase compared to a known DEM, preferably of the bald earth, 2.) interferometric correlation (polarimetric or otherwise), which is related to the volume scattering nature of the target, and 3.) interferometric correlation which is related to the temporal decorrelation of the target. Of these, while the volumetric aspect of interferometric correlation is of keen interest, because of the dominant error source of temporal decorrelation, it comes at the cost of the need to perform single-pass interferometry. While such satellite systems do exist (notably the TanDEM-X mission), for vegetation applications, lower frequency systems such as ALOS-1 and -2, and the future NASA radar mission at L-band, provides better signal returns from throughout the vegetation canopy. Hence, rather than relying on volumetric correlation to provide the desired FSH signature, repeat-pass observations of temporal decorrelation are coupled with a vegetation model for this decorrelation to determine the vegetation height. In order to demonstrate this technique, the University of Massachusetts has used 46-day repeat-pass ALOS data to estimate FSH over the US State of Maine, nearly a 10

  12. Nanoimprint lithography with a focused laser beam for the fabrication of nanopatterned microchannel molds.

    Science.gov (United States)

    Lim, Hyungjun; Ryu, Jihyeong; Kim, Geehong; Choi, Kee-Bong; Lee, Sunghwi; Lee, Jaejong

    2013-08-21

    We present a process based on nanoimprint lithography for the fabrication of a microchannel mold having nanopatterns formed at the bottoms of its microchannels. A focused laser beam selectively cures the resist in the micrometer scale during nanoimprint lithography. Nanopatterns within the microchannels may be used to control microfluidic behavior.

  13. A graphical simulation model of the entire DNA process associated with the analysis of short tandem repeat loci

    OpenAIRE

    Gill, Peter; Curran, James; Elliot, Keith

    2005-01-01

    The use of expert systems to interpret short tandem repeat DNA profiles in forensic, medical and ancient DNA applications is becoming increasingly prevalent as high-throughput analytical systems generate large amounts of data that are time-consuming to process. With special reference to low copy number (LCN) applications, we use a graphical model to simulate stochastic variation associated with the entire DNA process starting with extraction of sample, followed by the processing associated wi...

  14. Non-polydimethylsiloxane devices for oxygen-free flow lithography.

    Science.gov (United States)

    Bong, Ki Wan; Xu, Jingjing; Kim, Jong-Ho; Chapin, Stephen C; Strano, Michael S; Gleason, Karen K; Doyle, Patrick S

    2012-05-01

    Flow lithography has become a powerful particle synthesis technique. Currently, flow lithography relies on the use of polydimethylsiloxane microchannels, because the process requires local inhibition of polymerization, near channel interfaces, via oxygen permeation. The dependence on polydimethylsiloxane devices greatly limits the range of precursor materials that can be processed in flow lithography. Here we present oxygen-free flow lithography via inert fluid-lubrication layers for the synthesis of new classes of complex microparticles. We use an initiated chemical vapour deposition nano-adhesive bonding technique to create non-polydimethylsiloxane-based devices. We successfully synthesize microparticles with a sub-second residence time and demonstrate on-the-fly alteration of particle height. This technique greatly expands the synthesis capabilities of flow lithography, enabling particle synthesis, using water-insoluble monomers, organic solvents, and hydrophobic functional entities such as quantum dots and single-walled carbon nanotubes. As one demonstrative application, we created near-infrared barcoded particles for real-time, label-free detection of target analytes.

  15. Non-polydimethylsiloxane devices for oxygen-free flow lithography

    Science.gov (United States)

    Bong, Ki Wan; Xu, Jingjing; Kim, Jong-Ho; Chapin, Stephen C.; Strano, Michael S.; Gleason, Karen K.; Doyle, Patrick S.

    2012-05-01

    Flow lithography has become a powerful particle synthesis technique. Currently, flow lithography relies on the use of polydimethylsiloxane microchannels, because the process requires local inhibition of polymerization, near channel interfaces, via oxygen permeation. The dependence on polydimethylsiloxane devices greatly limits the range of precursor materials that can be processed in flow lithography. Here we present oxygen-free flow lithography via inert fluid-lubrication layers for the synthesis of new classes of complex microparticles. We use an initiated chemical vapour deposition nano-adhesive bonding technique to create non-polydimethylsiloxane-based devices. We successfully synthesize microparticles with a sub-second residence time and demonstrate on-the-fly alteration of particle height. This technique greatly expands the synthesis capabilities of flow lithography, enabling particle synthesis, using water-insoluble monomers, organic solvents, and hydrophobic functional entities such as quantum dots and single-walled carbon nanotubes. As one demonstrative application, we created near-infrared barcoded particles for real-time, label-free detection of target analytes.

  16. Injection Compression Molding of Replica Molds for Nanoimprint Lithography

    Directory of Open Access Journals (Sweden)

    Keisuke Nagato

    2014-03-01

    Full Text Available As a breakthrough in the cost and durability of molds for nanoimprint lithography (NIL, replica molds are fabricated by injection compression molding (ICM. ICM is commonly used for optical disks such as DVDs or Blu-ray disks and is also a practical fabrication method for nanostructures. In this paper, I successfully demonstrated the fabrication of cycloolefin polymer replica molds with structures smaller than 60 nm by ICM. Furthermore, ultraviolet (UV-NIL using these replica molds was demonstrated. UV-cured resist was replicated over an area of 60 mm diameter. The degree of replication by UV-NIL in the first usage of each replica mold had good repeatability. Because ICM is a high-throughput, low-cost process, the replica mold can be disposed of after a certain time for UV-NIL. This method leads to a high-integrity UV-NIL process of patterned media because multiple large-area replica molds can be fabricated simultaneously.

  17. Physical Limitations in Lithography for Microelectronics.

    Science.gov (United States)

    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)

  18. Improvements in Anatomy Knowledge When Utilizing a Novel Cyclical "Observe-Reflect-Draw-Edit-Repeat" Learning Process

    Science.gov (United States)

    Backhouse, Mark; Fitzpatrick, Michael; Hutchinson, Joseph; Thandi, Charankumal S.; Keenan, Iain D.

    2017-01-01

    Innovative educational strategies can provide variety and enhance student learning while addressing complex logistical and financial issues facing modern anatomy education. "Observe-Reflect-Draw-Edit-Repeat" (ORDER), a novel cyclical artistic process, has been designed based on cognitivist and constructivist learning theories, and on…

  19. Improvements in Anatomy Knowledge When Utilizing a Novel Cyclical "Observe-Reflect-Draw-Edit-Repeat" Learning Process

    Science.gov (United States)

    Backhouse, Mark; Fitzpatrick, Michael; Hutchinson, Joseph; Thandi, Charankumal S.; Keenan, Iain D.

    2017-01-01

    Innovative educational strategies can provide variety and enhance student learning while addressing complex logistical and financial issues facing modern anatomy education. "Observe-Reflect-Draw-Edit-Repeat" (ORDER), a novel cyclical artistic process, has been designed based on cognitivist and constructivist learning theories, and on…

  20. Topology optimization for optical projection lithography with manufacturing uncertainties

    DEFF Research Database (Denmark)

    Zhou, Mingdong; Lazarov, Boyan Stefanov; Sigmund, Ole

    2014-01-01

    This article presents a topology optimization approach for micro-and nano-devices fabricated by optical projection lithography. Incorporating the photolithography process and the manufacturing uncertainties into the topology optimization process results in a binary mask that can be sent directly...

  1. Porphyrin-Based Photocatalytic Lithography

    Energy Technology Data Exchange (ETDEWEB)

    Bearinger, J; Stone, G; Christian, A; Dugan, L; Hiddessen, A; Wu, K J; Wu, L; Hamilton, J; Stockton, C; Hubbell, J

    2007-10-15

    Photocatalytic lithography is an emerging technique that couples light with coated mask materials in order to pattern surface chemistry. We excite porphyrins to create radical species that photocatalytically oxidize, and thereby pattern, chemistries in the local vicinity. The technique advantageously does not necessitate mass transport or specified substrates, it is fast and robust and the wavelength of light does not limit the resolution of patterned features. We have patterned proteins and cells in order to demonstrate the utility of photocatalytic lithography in life science applications.

  2. Procedure for the Analysis of Repeatability and Reproducibility in Manufacturing Process

    Directory of Open Access Journals (Sweden)

    Gonzalo González Rey

    2015-12-01

    Full Text Available A procedure for the analysis of repeatability and reproducibility conditions (R&R in a manufacturing system is presented. The analysis of repeatability and reproducibility is based in measurement of dimensions from a piece or manufactured part. The procedure is fi xed by means of method of average and range with great acceptance and exclusivity in the study of measurement system analysis. This procedure and results derived of R&R analysis prove that method of average and range could be used in the stability study of manufacturing systems.

  3. Intra-rater repeatability of the Oxford foot model in healthy children in different stages of the foot roll over process during gait

    DEFF Research Database (Denmark)

    Curtis, D J; Bencke, J; Stebbins, J A

    2009-01-01

    BACKGROUND: The repeatability of the Oxford foot model has been reported, but possible variations in the repeatability during the foot roll over process have not been examined. The aim of this study was to determine the relative and absolute repeatability of the model for each stage of the foot r...

  4. Defect reduction for semiconductor memory applications using jet and flash imprint lithography

    Science.gov (United States)

    Ye, Zhengmao; Luo, Kang; Irving, J. W.; Lu, Xiaoming; Zhang, Wei; Fletcher, Brian; Liu, Weijun; Xu, Frank; LaBrake, Dwayne; Resnick, Douglas; Sreenivasan, S. V.

    2013-03-01

    Imprint lithography has been shown to be an effective technique for replication of nano-scale features. Jet and Flash Imprint Lithography (J-FIL) involves the field-by-field deposition and exposure of a low viscosity resist deposited by jetting technology onto the substrate. The patterned mask is lowered into the 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. Acceptance of imprint lithography for manufacturing will require demonstration that it can attain defect levels commensurate with the defect specifications of high end memory devices. Typical defectivity targets are on the order of 0.10/cm2. In previous studies, we have focused on defects such as random non-fill defects occurring during the resist filling process and repeater defects caused by interactions with particles on the substrate. In this work, we attempted to identify the critical imprint defect types using a mask with NAND Flash-like patterns at dimensions as small as 26nm. The two key defect types identified were line break defects induced by small particulates and airborne contaminants which result in local adhesion failure. After identification, the root cause of the defect was determined, and corrective measures were taken to either eliminate or reduce the defect source. As a result, we have been able to reduce defectivity levels by more than three orders of magnitude in only 12 months and are now achieving defectivity adders as small as 2 adders per lot of wafers.

  5. Graphene nanoribbon superlattices fabricated via He ion lithography

    Energy Technology Data Exchange (ETDEWEB)

    Archanjo, Braulio S., E-mail: bsarchanjo@inmetro.gov.br [Divisão de Metrologia de Materiais, Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO), Duque de Caxias, RJ 25250-020 (Brazil); Fragneaud, Benjamin [Divisão de Metrologia de Materiais, Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO), Duque de Caxias, RJ 25250-020 (Brazil); Departamento de Física, Universidade Federal de Juiz de Fora, Juiz de Fora, MG 36036-330 (Brazil); Gustavo Cançado, Luiz [Divisão de Metrologia de Materiais, Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO), Duque de Caxias, RJ 25250-020 (Brazil); Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, MG 30123-970 (Brazil); Winston, Donald [Hewlett-Packard Laboratories, 1501 Page Mill Road, Palo Alto, California 94304 (United States); Miao, Feng [Hewlett-Packard Laboratories, 1501 Page Mill Road, Palo Alto, California 94304 (United States); National Laboratory of Solid State Microstructures, School of Physics, National Center of Microstructures and Quantum Manipulation, Nanjing University, Nanjing 210093 (China); Alberto Achete, Carlos [Divisão de Metrologia de Materiais, Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO), Duque de Caxias, RJ 25250-020 (Brazil); Departamento de Engenharia Metalúrgica e de Materiais, Universidade Federal do Rio de janeiro, Rio de Janeiro RJ 21941-972 (Brazil); Medeiros-Ribeiro, Gilberto [Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, MG 30123-970 (Brazil); Hewlett-Packard Laboratories, 1501 Page Mill Road, Palo Alto, California 94304 (United States)

    2014-05-12

    Single-step nano-lithography was performed on graphene sheets using a helium ion microscope. Parallel “defect” lines of ∼1 μm length and ≈5 nm width were written to form nanoribbon gratings down to 20 nm pitch. Polarized Raman spectroscopy shows that crystallographic orientation of the nanoribbons was partially maintained at their lateral edges, indicating a high-fidelity lithography process. Furthermore, Raman analysis of large exposure areas with different ion doses reveals that He ions produce point defects with radii ∼ 2× smaller than do Ga ions, demonstrating that scanning-He{sup +}-beam lithography can texture graphene with less damage.

  6. Reducing DfM to practice: the lithography manufacturability assessor

    Science.gov (United States)

    Liebmann, Lars; Mansfield, Scott; Han, Geng; Culp, James; Hibbeler, Jason; Tsai, Roger

    2006-03-01

    The need for accurate quantification of all aspects of design for manufacturability using a mutually compatible set of quality-metrics and units-of-measure, is reiterated and experimentally verified. A methodology to quantify the lithography component of manufacturability is proposed and its feasibility demonstrated. Three stages of lithography manufacturability assessment are described: process window analysis on realistic integrated circuits following layout manipulations for resolution enhancement and the application of optical proximity correction, failure sensitivity analysis on simulated achievable dimensional bounds (a.k.a. variability bands), and yield risk analysis on iso-probability bands. The importance and feasibility of this technique is demonstrated by quantifying the lithography manufacturability impact of redundant contact insertion and Critical Area optimization in units that can be used to drive an overall layout optimization. The need for extensive experimental calibration and improved simulation accuracy is also highlighted.

  7. UV LED lithography with digitally tunable exposure dose

    Science.gov (United States)

    Yapici, Murat Kaya; Farhat, Ilyas

    2014-10-01

    This paper reports the development of a low-cost, portable, light-emitting diode (LED)-based ultraviolet (UV) exposure system. The major system components include UV-LEDs, a microcontroller, a digital-to-analog converter, and LED control circuitry. Through its front panel with a liquid crystal display and keypad, the UV-LED lithography system is able to receive user-defined values for exposure time and power, which allows the exposure dose to be tunable on demand. Compared to standard mask aligners, the UV-LED lithography system is a fraction of the cost, is simpler to construct using off-the shelf components, and does not require a complex infrastructure to operate. Such a reduction in system cost and complexity renders UV-LED lithography a perfect candidate for microlithography with large process windows typically suitable for MEMS, microfluidics applications.

  8. Advanced oxidation scanning probe lithography

    Science.gov (United States)

    Ryu, Yu K.; Garcia, Ricardo

    2017-04-01

    Force microscopy enables a variety of approaches to manipulate and/or modify surfaces. Few of those methods have evolved into advanced probe-based lithographies. Oxidation scanning probe lithography (o-SPL) is the only lithography that enables the direct and resist-less nanoscale patterning of a large variety of materials, from metals to semiconductors; from self-assembled monolayers to biomolecules. Oxidation SPL has also been applied to develop sophisticated electronic and nanomechanical devices such as quantum dots, quantum point contacts, nanowire transistors or mechanical resonators. Here, we review the principles, instrumentation aspects and some device applications of o-SPL. Our focus is to provide a balanced view of the method that introduces the key steps in its evolution, provides some detailed explanations on its fundamentals and presents current trends and applications. To illustrate the capabilities and potential of o-SPL as an alternative lithography we have favored the most recent and updated contributions in nanopatterning and device fabrication.

  9. Advanced oxidation scanning probe lithography.

    Science.gov (United States)

    Ryu, Yu K; Garcia, Ricardo

    2017-04-07

    Force microscopy enables a variety of approaches to manipulate and/or modify surfaces. Few of those methods have evolved into advanced probe-based lithographies. Oxidation scanning probe lithography (o-SPL) is the only lithography that enables the direct and resist-less nanoscale patterning of a large variety of materials, from metals to semiconductors; from self-assembled monolayers to biomolecules. Oxidation SPL has also been applied to develop sophisticated electronic and nanomechanical devices such as quantum dots, quantum point contacts, nanowire transistors or mechanical resonators. Here, we review the principles, instrumentation aspects and some device applications of o-SPL. Our focus is to provide a balanced view of the method that introduces the key steps in its evolution, provides some detailed explanations on its fundamentals and presents current trends and applications. To illustrate the capabilities and potential of o-SPL as an alternative lithography we have favored the most recent and updated contributions in nanopatterning and device fabrication.

  10. Graphic Arts/Offset Lithography.

    Science.gov (United States)

    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…

  11. Maskless, reticle-free, lithography

    Science.gov (United States)

    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.

  12. Lithography for enabling advances in integrated circuits and devices.

    Science.gov (United States)

    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.

  13. EUV lithography imaging using novel pellicle membranes

    Science.gov (United States)

    Pollentier, Ivan; Vanpaemel, Johannes; Lee, Jae Uk; Adelmann, Christoph; Zahedmanesh, Houman; Huyghebaert, Cedric; Gallagher, Emily E.

    2016-03-01

    EUV mask protection against defects during use remains a challenge for EUV lithography. A stand-off protective membrane - a pellicle - is targeted to prevent yield losses in high volume manufacturing during handling and exposure, just as it is for 193nm lithography. The pellicle is thin enough to transmit EUV exposure light, yet strong enough to remain intact and hold any particles out of focus during exposure. The development of pellicles for EUV is much more challenging than for 193nm lithography for multiple reasons including: high absorption of most materials at EUV wavelength, pump-down sequences in the EUV vacuum system, and exposure to high intensity EUV light. To solve the problems of transmission and film durability, various options have been explored. In most cases a thin core film is considered, since the deposition process for this is well established and because it is the simplest option. The transmission specification typically dictates that membranes are very thin (~50nm or less), which makes both fabrication and film mechanical integrity difficult. As an alternative, low density films (e.g. including porosity) will allow thicker membranes for a given transmission specification, which is likely to improve film durability. The risk is that the porosity could influence the imaging. At imec, two cases of pellicle concepts based on reducing density have been assessed : (1) 3D-patterned SiN by directed self-assembly (DSA), and (2) carbon nanomaterials such as carbon nanotubes (CNT) and carbon nanosheets (CNS). The first case is based on SiN membranes that are 3D-patterned by Directed Self Assembly (DSA). The materials are tested relative to the primary specifications: EUV transmission and film durability. A risk assessment of printing performance is provided based on simulations of scattered energy. General conclusions on the efficacy of various approaches will provided.

  14. New approaches to atomic force microscope lithography on silicon

    DEFF Research Database (Denmark)

    Birkelund, Karen; Thomsen, Erik Vilain; Rasmussen, Jan Pihl

    1997-01-01

    We have investigated new approaches to the formation of conducting nanowires on crystalline silicon surfaces using atomic force microscope (AFM) lithography. To increase processing speed and reduce wear of the AFM tip, large-scale structures are formed with a direct laser write setup, while the AFM...

  15. Fast thermal nanoimprint lithography by a stamp with integrated heater

    DEFF Research Database (Denmark)

    Tormen, Massimo; Malureanu, Radu; Pedersen, Rasmus Haugstrup

    2008-01-01

    We propose fast nanoimprinting lithography (NIL) process based on the use of stamps with integrated heater. The latter consists of heavily ion implantation n-type doped silicon layer buried below the microstructured surface of the stamp. The stamp is heated by Joule effect, by 50 μs 25 Hz...

  16. Inverse lithography source optimization via compressive sensing.

    Science.gov (United States)

    Song, Zhiyang; Ma, Xu; Gao, Jie; Wang, Jie; Li, Yanqiu; Arce, Gonzalo R

    2014-06-16

    Source optimization (SO) has emerged as a key technique for improving lithographic imaging over a range of process variations. Current SO approaches are pixel-based, where the source pattern is designed by solving a quadratic optimization problem using gradient-based algorithms or solving a linear programming problem. Most of these methods, however, are either computational intensive or result in a process window (PW) that may be further extended. This paper applies the rich theory of compressive sensing (CS) to develop an efficient and robust SO method. In order to accelerate the SO design, the source optimization is formulated as an underdetermined linear problem, where the number of equations can be much less than the source variables. Assuming the source pattern is a sparse pattern on a certain basis, the SO problem is transformed into a l1-norm image reconstruction problem based on CS theory. The linearized Bregman algorithm is applied to synthesize the sparse optimal source pattern on a representation basis, which effectively improves the source manufacturability. It is shown that the proposed linear SO formulation is more effective for improving the contrast of the aerial image than the traditional quadratic formulation. The proposed SO method shows that sparse-regularization in inverse lithography can indeed extend the PW of lithography systems. A set of simulations and analysis demonstrate the superiority of the proposed SO method over the traditional approaches.

  17. Computational study on UV curing characteristics in nanoimprint lithography: Stochastic simulation

    Science.gov (United States)

    Koyama, Masanori; Shirai, Masamitsu; Kawata, Hiroaki; Hirai, Yoshihiko; Yasuda, Masaaki

    2017-06-01

    A computational simulation model of UV curing in nanoimprint lithography based on a simplified stochastic approach is proposed. The activated unit reacts with a randomly selected monomer within a critical reaction radius. Cluster units are chained to each other. Then, another monomer is activated and the next chain reaction occurs. This process is repeated until a virgin monomer disappears within the reaction radius or until the activated monomers react with each other. The simulation model well describes the basic UV curing characteristics, such as the molecular weight distributions of the reacted monomers and the effect of the initiator concentration on the conversion ratio. The effects of film thickness on UV curing characteristics are also studied by the simulation.

  18. A physical resist shrinkage model for full-chip lithography simulations

    Science.gov (United States)

    Liu, Peng; Zheng, Leiwu; Ma, Maggie; Zhao, Qian; Fan, Yongfa; Zhang, Qiang; Feng, Mu; Guo, Xin; Wallow, Tom; Gronlund, Keith; Goossens, Ronald; Zhang, Gary; Lu, Yenwen

    2016-03-01

    Strong resist shrinkage effects have been widely observed in resist profiles after negative tone development (NTD) and therefore must be taken into account in computational lithography applications. However, existing lithography simulation tools, especially those designed for full-chip applications, lack resist shrinkage modeling capabilities because they are not needed until only recently when NTD processes begin to replace the conventional positive tone development (PTD) processes where resist shrinkage effects are negligible. In this work we describe the development of a physical resist shrinkage (PRS) model for full-chip lithography simulations and present its accuracy evaluation against experimental data.

  19. Femtolitre chemistry assisted by microfluidic pen lithography.

    Science.gov (United States)

    Carbonell, Carlos; Stylianou, Kyriakos C; Hernando, Jordi; Evangelio, Emi; Barnett, Sarah A; Nettikadan, Saju; Imaz, Inhar; Maspoch, Daniel

    2013-01-01

    Chemical reactions at ultrasmall volumes are becoming increasingly necessary to study biological processes, to synthesize homogenous nanostructures and to perform high-throughput assays and combinatorial screening. Here we show that a femtolitre reaction can be realized on a surface by handling and mixing femtolitre volumes of reagents using a microfluidic stylus. This method, named microfluidic pen lithography, allows mixing reagents in isolated femtolitre droplets that can be used as reactors to conduct independent reactions and crystallization processes. This strategy overcomes the high-throughput limitations of vesicles and micelles and obviates the usually costly step of fabricating microdevices and wells. We anticipate that this process enables performing distinct reactions (acid-base, enzymatic recognition and metal-organic framework synthesis), creating multiplexed nanoscale metal-organic framework arrays, and screening combinatorial reactions to evaluate the crystallization of novel peptide-based materials.

  20. Femtolitre chemistry assisted by microfluidic pen lithography

    Science.gov (United States)

    Carbonell, Carlos; Stylianou, Kyriakos C.; Hernando, Jordi; Evangelio, Emi; Barnett, Sarah A.; Nettikadan, Saju; Imaz, Inhar; Maspoch, Daniel

    2013-01-01

    Chemical reactions at ultrasmall volumes are becoming increasingly necessary to study biological processes, to synthesize homogenous nanostructures and to perform high-throughput assays and combinatorial screening. Here we show that a femtolitre reaction can be realized on a surface by handling and mixing femtolitre volumes of reagents using a microfluidic stylus. This method, named microfluidic pen lithography, allows mixing reagents in isolated femtolitre droplets that can be used as reactors to conduct independent reactions and crystallization processes. This strategy overcomes the high-throughput limitations of vesicles and micelles and obviates the usually costly step of fabricating microdevices and wells. We anticipate that this process enables performing distinct reactions (acid-base, enzymatic recognition and metal-organic framework synthesis), creating multiplexed nanoscale metal-organic framework arrays, and screening combinatorial reactions to evaluate the crystallization of novel peptide-based materials. PMID:23863998

  1. Sequential infiltration synthesis for advanced lithography

    Science.gov (United States)

    Darling, Seth B.; Elam, Jeffrey W.; Tseng, Yu-Chih; Peng, Qing

    2015-03-17

    A plasma etch resist material modified by an inorganic protective component via sequential infiltration synthesis (SIS) and methods of preparing the modified resist material. The modified resist material is characterized by an improved resistance to a plasma etching or related process relative to the unmodified resist material, thereby allowing formation of patterned features into a substrate material, which may be high-aspect ratio features. The SIS process forms the protective component within the bulk resist material through a plurality of alternating exposures to gas phase precursors which infiltrate the resist material. The plasma etch resist material may be initially patterned using photolithography, electron-beam lithography or a block copolymer self-assembly process.

  2. ''MBE-Litho'': 3 nm-thick amorphous GaAs oxidized thin film functioning as highly sensitive inorganic resist for EB lithography and oxide mask for selective processes

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, Kazuhiro; Hirokawa, Yuki; Ushio, Shoji; Kaneko, Tadaaki [Department of Physics, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 (Japan)

    2011-02-15

    Molecular beam epitaxy (MBE) is one of the growth methods, which has been widely used for single crystalline semiconductor materials. In this study, we report a novel function of a 3 nm-thick amorphous GaAs thin layer deposited using MBE at room temperature. Its oxidized region exposed to H{sub 2}O-vapor ambient works as a highly sensitive inorganic resist film for low-energy electron-beam (LE-EB) lithography of 1-5 keV. In this method, the surface area modified by LE-EB direct writing provides a thermally stable oxide pattern, which can be directly applied to successive selective processes such as etching and growth under MBE environment. All the condition required for its selective etching/growth is to remove the background residual GaAs oxide of EB non-irradiated area in the same UHV chamber. Thus, MBE gives the simplest and most efficient solution to all the processes including the resist film pre-depositing, the background oxide removing and the successive etching/growth functions. We call this solution ''MBE-Litho ''. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  3. Fabrication of an array-like freeform molding tool for UV-replication using a step and repeat process

    Science.gov (United States)

    Dunkel, J.; Wippermann, F.; Brückner, A.; Reimann, A.; Bräuer, A.

    2013-05-01

    Artificial compound eye cameras are a prominent approach of next generation wafer level cameras for consumer electronics due to their lower z-height compared to conventional single aperture objectives. In order to address low cost and high volume markets, their fabrication is based on a wafer level UV-replication process. The image quality of compound eye cameras can be increased significantly by the use of refractive freeform arrays (RFFA) instead of conventional microlens arrays. Therefore, we present the fabrication of a RFFA wafer level molding tool by a step and repeat process for the first time. The surface qualities of the fabricated structures were characterized with a white light interferometer.

  4. Predicting lithography costs: guidance for <= 32 nm patterning solutions

    Science.gov (United States)

    Hazelton, Andrew J.; Wüest, Andrea; Hughes, Greg; Lercel, Michael

    2008-05-01

    Extending lithography to 32 nm and 22 nm half pitch requires the introduction of new lithography technologies, such as EUVL or high-index immersion, or new techniques, such as double patterning. All of these techniques introduce large changes into the single exposure immersion lithography process as used for the 45 nm half pitch node. Therefore, cost per wafer is a concern. In this paper, total patterning costs are estimated for the 32 nm and 22 nm half pitch nodes through the application of cost-of-ownership models based on the tool, mask, and process costs. For all cases, the cost of patterning at 32 nm half pitch for critical layers will be more expensive than in prior generations. Mask costs are observed to be a significant component of lithography costs even up to a mask usage of 10,000 wafers/mask in most cases. The more simple structure of EUVL masks reduces the mask cost component and results in EUVL being the most cost-effective patterning solution under the assumptions of high throughput and good mask blank defect density.

  5. 步进扫描光刻机加速时间段的S曲线规化%S-curve Planning for Acceleration Process of Step-and-scan Lithography

    Institute of Scientific and Technical Information of China (English)

    武志鹏; 陈兴林; 郝中洋

    2012-01-01

    To improve the productivity of step-and-scan lithography, a fifth-order S-curve with minimum time and jerk characteristics is proposed. On condition that the scanning speed is a constant, a fifth-order S-curve of the acceleration process is designed based on the minimum time and jerk optimization index. A variable parameter is added to the jerk item of the optimization index and can be adjusted based on acceleration time and actuator motors, and the acceleration time can be induced within the limits of the lithography equipment. Simulation results show that the optimal S-cure can significantly reduce the acceleration time compared with the normal S-curve, and the acceleration curve is smooth. The jerk parameter has a great effect on the acceleration time and smoothness of the S-curve.%为提高步进扫描式光刻机的生产效率,提出了一种具有时间最优和冲击最小的5阶S曲线.在最大扫描速度恒定的前提下,以最小时间和冲击为优化指标,设计了加速时间段内的5阶S曲线.在优化指标冲击力项中引入了可变参数,可以根据加速时间和执行电机进行调整,在光刻机设备允许的范围内缩短加速时间.仿真结果表明,相对于数值方法设计的S曲线,优化S曲线加速时间明显缩短并且加速度曲线平滑.冲击力项系数对加速时间和S曲线的平滑性有很大影响.

  6. Direct optical lithography of functional inorganic nanomaterials

    Science.gov (United States)

    Wang, Yuanyuan; Fedin, Igor; Zhang, Hao; Talapin, Dmitri V.

    2017-07-01

    Photolithography is an important manufacturing process that relies on using photoresists, typically polymer formulations, that change solubility when illuminated with ultraviolet light. Here, we introduce a general chemical approach for photoresist-free, direct optical lithography of functional inorganic nanomaterials. The patterned materials can be metals, semiconductors, oxides, magnetic, or rare earth compositions. No organic impurities are present in the patterned layers, which helps achieve good electronic and optical properties. The conductivity, carrier mobility, dielectric, and luminescence properties of optically patterned layers are on par with the properties of state-of-the-art solution-processed materials. The ability to directly pattern all-inorganic layers by using a light exposure dose comparable with that of organic photoresists provides an alternate route for thin-film device manufacturing.

  7. Photomask displacement technology for continuous profile generation by mask aligner lithography

    Science.gov (United States)

    Weichelt, Tina; Kinder, Robert; Zeitner, Uwe D.

    2016-12-01

    Mask aligner lithography is one of the most widely used technologies for micro-optical elements fabrication. It offers a high throughput with high-yield processing. With different resolution enhancement technologies shadow printing is a mature alternative to the more expensive projection or electron-beam lithography. We are presenting a novel mask aligner tool that allows shifting the photomask with high accuracy between sequential exposure shots. It offers possibilities such as double patterning or gray tone lithography by applying different light doses at different locations. Within this publication, we show the first results for high resolution blazed grating structures generated in photoresist by multiple exposures using a conventional binary photomask.

  8. Hybrid UV Lithography for 3D High-Aspect-Ratio Microstructures

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sungmin; Nam, Gyungmok; Kim, Jonghun; Yoon, Sang-Hee [Inha Univ, Incheon (Korea, Republic of)

    2016-08-15

    Three-dimensional (3D) high-aspect-ratio (HAR) microstructures for biomedical applications (e.g., microneedle, microadhesive, etc.) are microfabricated using the hybrid ultraviolet (UV) lithography in which inclined, rotational, and reverse-side UV exposure processes are combined together. The inclined and rotational UV exposure processes are intended to fabricate tapered axisymmetric HAR microstructures; the reverse-side UV exposure process is designed to sharpen the end tip of the microstructures by suppressing the UV reflection on a bottom substrate which is inevitable in conventional UV lithography. Hybrid UV lithography involves fabricating 3D HAR microstructures with an epoxy-based negative photoresist, SU-8, using our customized UV exposure system. The effects of hybrid UV lithography parameters on the geometry of the 3D HAR microstructures (aspect ratio, radius of curvature of the end tip, etc.) are measured. The dependence of the end-tip shape on SU-8 soft-baking condition is also discussed.

  9. Co-Referential Processing of Pronouns and Repeated Names in Italian

    Science.gov (United States)

    de Carvalho Maia, Jefferson; Vernice, Mirta; Gelormini-Lezama, Carlos; Lima, Maria Luiza Cunha; Almor, Amit

    2017-01-01

    In this study, we investigate whether co-referential processing across sentence boundaries is driven by universal properties of the general architecture of memory systems and whether cross-linguistic differences concerning the number of anaphoric forms available in a language's referential inventory can impact the process of inter-sentential…

  10. High aspect ratio tungsten grating on ultrathin Si membranes for extreme UV lithography

    Science.gov (United States)

    Peng, Xinsheng; Ying, Yulong

    2016-09-01

    Extreme ultraviolet lithography is one of the modern lithography tools for high-volume manufacturing with 22 nm resolution and beyond. But critical challenges exist to the design and fabrication of large-scale and highly efficient diffraction transmission gratings, significantly reducing the feature sizes down to 22 nm and beyond. To achieve such a grating, the surface flatness, the line edge roughness, the transmission efficiency and aspect ratio should be improved significantly. Delachat et al (2015 Nanotechnology 26 108262) develop a full process to fabricate a tungsten diffraction grating on an ultrathin silicon membrane with higher aspect ratio up to 8.75 that met all the aforementioned requirements for extreme ultraviolet lithography. This process is fully compatible with standard industrial extreme ultraviolet lithography.

  11. High aspect ratio tungsten grating on ultrathin Si membranes for extreme UV lithography.

    Science.gov (United States)

    Peng, Xinsheng; Ying, Yulong

    2016-09-02

    Extreme ultraviolet lithography is one of the modern lithography tools for high-volume manufacturing with 22 nm resolution and beyond. But critical challenges exist to the design and fabrication of large-scale and highly efficient diffraction transmission gratings, significantly reducing the feature sizes down to 22 nm and beyond. To achieve such a grating, the surface flatness, the line edge roughness, the transmission efficiency and aspect ratio should be improved significantly. Delachat et al (2015 Nanotechnology 26 108262) develop a full process to fabricate a tungsten diffraction grating on an ultrathin silicon membrane with higher aspect ratio up to 8.75 that met all the aforementioned requirements for extreme ultraviolet lithography. This process is fully compatible with standard industrial extreme ultraviolet lithography.

  12. Microfluidic Lithography of Bioinspired Helical Micromotors.

    Science.gov (United States)

    Yu, Yunru; Shang, Luoran; Gao, Wei; Zhao, Ze; Wang, Huan; Zhao, Yuanjin

    2017-07-29

    Considerable efforts have been devoted to developing artificial micro/nanomotors that can convert energy into movement. A flow lithography integrated microfluidic spinning and spiraling system is developed for the continuous generation of bioinspired helical micromotors. Because the generation processes could be precisely tuned by adjusting the flow rates and the illuminating frequency, the length, diameter, and pitch of the helical micromotors were highly controllable. Benefiting from the fast online gelation and polymerization, the resultant helical micromotors could be imparted with Janus, triplex, and core-shell cross-sectional structures that have never been achieved by other methods. Owing to the spatially controlled encapsulation of functional nanoparticles in the microstructures, the helical micromotors can perform locomotion not only by magnetically actuated rotation or corkscrew motion but also through chemically powered catalytic reaction. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. DNA Nanostructures-Mediated Molecular Imprinting Lithography.

    Science.gov (United States)

    Tian, Cheng; Kim, Hyojeong; Sun, Wei; Kim, Yunah; Yin, Peng; Liu, Haitao

    2017-01-24

    This paper describes the fabrication of polymer stamps using DNA nanostructure templates. This process creates stamps having diverse nanoscale features with dimensions ranging from several tens of nanometers to micrometers. DNA nanostructures including DNA nanotubes, stretched λ-DNA, two-dimensional (2D) DNA brick crystals with three-dimensional (3D) features, hexagonal DNA 2D arrays, and triangular DNA origami were used as master templates to transfer patterns to poly(methyl methacrylate) and poly(l-lactic acid) with high fidelity. The resulting polymer stamps were used as molds to transfer the pattern to acryloxy perfluoropolyether polymer. This work establishes an approach to using self-assembled DNA templates for applications in soft lithography.

  14. Overlay considerations for 300-mm lithography

    Science.gov (United States)

    Mono, Tobias; Schroeder, Uwe P.; Nees, Dieter; Palitzsch, Katrin; Koestler, Wolfram; Bruch, Jens; Kramp, Sirko; Veldkamp, Markus; Schuster, Ralf

    2003-05-01

    Generally, the potential impact of systematical overlay errors on 300mm wafers is much larger than on 200mm wafers. Process problems which are merely identified as minor edge yield detractors on 200mm wafers, can evolve as major roadblocks for 300mm lithography. Therefore, it is commonly believed that achieving product overlay specifications on 300mm wafers is much more difficult than on 200mm wafers. Based on recent results on high volume 300mm DRAM manufacturing, it is shown that in reality this assumption does not hold. By optimizing the process, overlay results can be achieved which are comparable to the 200mm reference process. However, the influence of non-lithographic processes on the overlay performance becomes much more critical. Based on examples for specific overlay signatures, the influence of several processes on the overlay characteristics of 300mm wafers is demonstrated. Thus, process setup and process changes need to be analyzed monitored much more carefully. Any process variations affecting wafer related overlay have to be observed carefully. Fast reaction times are critical to avoid major yield loss. As the semiconductor industry converts to 300mm technology, lithographers have to focus more than ever on process integration aspects.

  15. Manycore processing of repeated range queries over massive moving objects observations

    DEFF Research Database (Denmark)

    Lettich, Francesco; Orlando, Salvatore; Silvestri, Claudio;

    2014-01-01

    The ability to timely process significant amounts of continuously updated spatial data is mandatory for an increasing number of applications. Parallelism enables such applications to face this data-intensive challenge and allows the devised systems to feature low latency and high scalability. In ...

  16. Sucrose purification and repeated ethanol production from sugars remaining in sweet sorghum juice subjected to a membrane separation process.

    Science.gov (United States)

    Sasaki, Kengo; Tsuge, Yota; Kawaguchi, Hideo; Yasukawa, Masahiro; Sasaki, Daisuke; Sazuka, Takashi; Kamio, Eiji; Ogino, Chiaki; Matsuyama, Hideto; Kondo, Akihiko

    2017-08-01

    The juice from sweet sorghum cultivar SIL-05 (harvested at physiological maturity) was extracted, and the component sucrose and reducing sugars (such as glucose and fructose) were subjected to a membrane separation process to purify the sucrose for subsequent sugar refining and to obtain a feedstock for repeated bioethanol production. Nanofiltration (NF) of an ultrafiltration (UF) permeate using an NTR-7450 membrane (Nitto Denko Corporation, Osaka, Japan) concentrated the juice and produced a sucrose-rich fraction (143.2 g L(-1) sucrose, 8.5 g L(-1) glucose, and 4.5 g L(-1) fructose). In addition, the above NF permeate was concentrated using an ESNA3 NF membrane to provide concentrated permeated sugars (227.9 g L(-1)) and capture various amino acids in the juice, enabling subsequent ethanol fermentation without the addition of an exogenous nitrogen source. Sequential batch fermentation using the ESNA3 membrane concentrate provided an ethanol titer and theoretical ethanol yield of 102.5-109.5 g L(-1) and 84.4-89.6%, respectively, throughout the five-cycle batch fermentation by Saccharomyces cerevisiae BY4741. Our results demonstrate that a membrane process using UF and two types of NF membranes has the potential to allow sucrose purification and repeated bioethanol production.

  17. Multicusp sources for ion beam lithography applications

    Energy Technology Data Exchange (ETDEWEB)

    Leung, K.N.; Herz, P.; Kunkel, W.B.; Lee, Y.; Perkins, L.; Pickard, D.; Sarstedt, M.; Weber, M.; Williams, M.D.

    1995-05-01

    Application of the multicusp source for Ion Projection Lithography is described. It is shown that the longitudinal energy spread of the positive ions at the extraction aperture can be reduced by employing a magnetic filter. The advantages of using volume-produced H{sup {minus}} ions for ion beam lithography is also discussed.

  18. Multicusp sources for ion beam lithography applications

    Energy Technology Data Exchange (ETDEWEB)

    Leung, K.N.; Herz, P.; Kunkel, W.B.; Lee, Y.; Perkins, L.; Pickard, D.; Sarstedt, M.; Weber, M.; Williams, M.D. [Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720 (United States)

    1995-11-01

    Application of the multicusp source for ion projection lithography is described. It is shown that the longitudinal energy spread of the positive ions at the extraction aperture can be reduced by employing a magnetic filter. The advantages of using volume-produced H{sup {minus}} ions for ion beam lithography are also discussed. {copyright} {ital 1995} {ital American} {ital Vacuum} {ital Society}

  19. 3D-Nanomachining using corner lithography

    NARCIS (Netherlands)

    Berenschot, Johan W.; Tas, Niels Roelof; Jansen, Henricus V.; Elwenspoek, Michael Curt

    2008-01-01

    We present a fabrication method to create 3D nano structures without the need for nano lithography. The method, named "corner lithography" is based on conformal deposition and subsequent isotropic thinning of a thin film. The material that remains in sharp concave corners is either used as a mask or

  20. Alternative lithography strategies for flexible electronics

    NARCIS (Netherlands)

    Moonen, P.

    2012-01-01

    Main aim of the research has been the development of alternative lithography strategies for the fabrication of complex, flexible electronic devices. Flexible bottom-contact, bottom-gate thin-film transistors were solely patterned with UV nanoimprint lithography on poly(ethylene naphthalate) foil. Pa

  1. High-Throughput Contact Flow Lithography.

    Science.gov (United States)

    Le Goff, Gaelle C; Lee, Jiseok; Gupta, Ankur; Hill, William Adam; Doyle, Patrick S

    2015-10-01

    High-throughput fabrication of graphically encoded hydrogel microparticles is achieved by combining flow contact lithography in a multichannel microfluidic device and a high capacity 25 mm LED UV source. Production rates of chemically homogeneous particles are improved by two orders of magnitude. Additionally, the custom-built contact lithography instrument provides an affordable solution for patterning complex microstructures on surfaces.

  2. Benchtop micromolding of polystyrene by soft lithography.

    Science.gov (United States)

    Wang, Yuli; Balowski, Joseph; Phillips, Colleen; Phillips, Ryan; Sims, Christopher E; Allbritton, Nancy L

    2011-09-21

    Polystyrene (PS), a standard material for cell culture consumable labware, was molded into microstructures with high fidelity of replication by an elastomeric polydimethylsiloxane (PDMS) mold. The process was a simple, benchtop method based on soft lithography using readily available materials. The key to successful replica molding by this simple procedure relies on the use of a solvent, for example, gamma-butyrolactone, which dissolves PS without swelling the PDMS mold. PS solution was added to the PDMS mold, and evaporation of the solvent was accomplished by baking the mold on a hotplate. Microstructures with feature sizes as small as 3 μm and aspect ratios as large as 7 were readily molded. Prototypes of microfluidic chips made from PS were prepared by thermal bonding of a microchannel molded in PS with a flat PS substrate. The PS microfluidic chip displayed much lower adsorption and absorption of hydrophobic molecules (e.g. rhodamine B) compared to a comparable chip created from PDMS. The molded PS surface exhibited stable surface properties after plasma oxidation as assessed by contact angle measurement. The molded, oxidized PS surface remained an excellent surface for cell culture based on cell adhesion and proliferation. To demonstrate the application of this process for cell biology research, PS was micromolded into two different microarray formats, microwells and microposts, for segregation and tracking of non-adherent and adherent cells, respectively. The micromolded PS possessed properties that were ideal for biological and bioanalytical needs, thus making it an alternative material to PDMS and suitable for building lab-on-a-chip devices by soft lithography methods. This journal is © The Royal Society of Chemistry 2011

  3. Integrated Data Processing Methodology for Airborne Repeat-pass Differential SAR Interferometry

    Science.gov (United States)

    Dou, C.; Guo, H.; Han, C.; Yue, X.; Zhao, Y.

    2014-11-01

    Short temporal baseline and multiple ground deformation information can be derived from the airborne differential synthetic aperture radar Interforemetry (D-InSAR). However, affected by the turbulence of the air, the aircraft would deviate from the designed flight path with high frequent vibrations and changes both in the flight trajectory and attitude. Restricted by the accuracy of the position and orientation system (POS), these high frequent deviations can not be accurately reported, which would pose great challenges in motion compensation and interferometric process. Thus, these challenges constrain its wider applications. The objective of this paper is to investigate the accurate estimation and compensation of the residual motion errors in the airborne SAR imagery and time-varying baseline errors between the diffirent data acquirations, furthermore, to explore the integration data processing theory for the airborne D-InSAR system, and thus help to accomplish the correct derivation of the ground deformation by using the airborne D-InSAR measurements.

  4. A Software Process Framework for the SEI Capability Maturity Model: Repeatable Level

    Science.gov (United States)

    1993-06-01

    Vilfredo Pareto , that most effects I come from relatively few causes, i.e., 80% of the effects come from 20% of the possible causes. peer review - A review...to the next maturity level. Using the Pareto principle [Juran88b], the CMM prescribes the "vital few" key process areas to focus on depending on an...or interfacing with the individuals responsible for performing in the topic area. (See train for contrast.) Pareto analysis - The analysis of defects

  5. Design for manufacturability with advanced lithography

    CERN Document Server

    Yu, Bei

    2016-01-01

    This book introduces readers to the most advanced research results on Design for Manufacturability (DFM) with multiple patterning lithography (MPL) and electron beam lithography (EBL).  The authors describe in detail a set of algorithms/methodologies to resolve issues in modern design for manufacturability problems with advanced lithography.  Unlike books that discuss DFM from the product level, or physical manufacturing level, this book describes DFM solutions from a circuit design level, such that most of the critical problems can be formulated and solved through combinatorial algorithms. Enables readers to tackle the challenge of layout decompositions for different patterning techniques; Presents a coherent framework, including standard cell compliance and detailed placement, to enable Triple Patterning Lithography (TPL) friendly design; Includes coverage of the design for manufacturability with E-Beam lithography.

  6. Three dimensional polymer waveguide using hybrid lithography.

    Science.gov (United States)

    Wang, Huanran; Liu, Yu; Jiang, Minghui; Chen, Changming; Wang, Xibin; Wang, Fei; Zhang, Daming; Yi, Yunji

    2015-10-01

    A three dimensional polymer waveguide with taper structure was demonstrated and fabricated by a reliable and effective hybrid lithography. The hybrid lithography consists of lithography to fabricate a polymer waveguide and gray scale lithography to fabricate a polymer taper structure. Laser ablation and shadow aluminum evaporation were designed for gray scale lithography. The length of the gray scale region ranging from 20 to 400 μm could be controlled by the laser power, the ablation speed, and the aluminum thickness. The slope angle was determined by the length of the gray scale region and the thickness of the photoresist. The waveguide taper structure could be transferred to the lower layer by the etching method. The taper structure can be used for integration of the waveguide with different dimensions.

  7. 450mm wafer patterning with jet and flash imprint lithography

    Science.gov (United States)

    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.

  8. Large area mold fabrication for the nanoimprint lithography using electron beam lithography

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The mold fabrication is a critical issue for the development of nanoimprint lithography as an effective low-cost and mass production process.This paper describes the fabrication process developed to fabricate the large area nanoimprint molds on the silicon wafers.The optimization of e-beam exposure dose and pattern design is presented.The overlayer process is developed to improve the field stitching accuracy of e-beam exposure,and around 10 nm field stitching accuracy is obtained.By means of the optimization of the e-beam exposure dose,pattern design and overlayer process,large area nanoimprint molds having dense line structures with around 10 nm field stitching accuracy have been fabricated.The fabricated mold was used to imprint commercial imprinting resist.

  9. Scanning Probe Photonic Nanojet Lithography.

    Science.gov (United States)

    Jacassi, Andrea; Tantussi, Francesco; Dipalo, Michele; Biagini, Claudio; Maccaferri, Nicolò; Bozzola, Angelo; De Angelis, Francesco

    2017-09-08

    The use of nano/microspheres or beads for optical nanolithography is a consolidated technique for achieving subwavelength structures using a cost-effective approach; this method exploits the capability of the beads to focus electromagnetic waves into subwavelength beams called photonic nanojets, which are used to expose the photoresist on which the beads are placed. However, this technique has only been used to produce regular patterns based on the spatial arrangement of the beads on the substrate, thus considerably limiting the pool of applications. Here, we present a novel microsphere-based optical lithography technique that offers high subwavelength resolution and the possibility of generating any arbitrary pattern. The presented method consists of a single microsphere embedded in an AFM cantilever, which can be controlled using the AFM motors to write arbitrary patterns with subwavelength resolution (down to 290 nm with a 405 nm laser). The performance of the proposed technique can compete with those of commercial high-resolution standard instruments, with the advantage of a one-order-of-magnitude reduction in costs. This approach paves the way for direct integration of cost-effective, high-resolution optical lithography capabilities into several existing AFM systems.

  10. Moiré Nanosphere Lithography.

    Science.gov (United States)

    Chen, Kai; Rajeeva, Bharath Bangalore; Wu, Zilong; Rukavina, Michael; Dao, Thang Duy; Ishii, Satoshi; Aono, Masakazu; Nagao, Tadaaki; Zheng, Yuebing

    2015-06-23

    We have developed moiré nanosphere lithography (M-NSL), which incorporates in-plane rotation between neighboring monolayers, to extend the patterning capability of conventional nanosphere lithography (NSL). NSL, which uses self-assembled layers of monodisperse micro/nanospheres as masks, is a low-cost, scalable nanofabrication technique and has been widely employed to fabricate various nanoparticle arrays. Combination with dry etching and/or angled deposition has greatly enriched the family of nanoparticles NSL can yield. In this work, we introduce a variant of this technique, which uses sequential stacking of polystyrene nanosphere monolayers to form a bilayer crystal instead of conventional spontaneous self-assembly. Sequential stacking leads to the formation of moiré patterns other than the usually observed thermodynamically stable configurations. Subsequent O2 plasma etching results in a variety of complex nanostructures. Using the etched moiré patterns as masks, we have fabricated complementary gold nanostructures and studied their optical properties. We believe this facile technique provides a strategy to fabricate complex nanostructures or metasurfaces.

  11. DNA Origami Mask for Sub-Ten-Nanometer Lithography.

    Science.gov (United States)

    Diagne, Cheikh Tidiane; Brun, Christophe; Gasparutto, Didier; Baillin, Xavier; Tiron, Raluca

    2016-07-26

    DNA nanotechnology is currently widely explored and especially shows promises for advanced lithography due to its ability to define nanometer scale features. We demonstrate a 9 × 14 nm(2) hole pattern transfer from DNA origami into an SiO2 layer with a sub-10-nm resolution using anhydrous HF vapor in a semiconductor etching machine. We show that the resulting SiO2 pattern inherits its shape from the DNA structure within a process time ranging from 30 to 60 s at an etching rate of 0.2 nm/s. At 600 s of etching, the SiO2 pattern meets corrosion and the overall etching reaction is blocked. These results, in addition to the entire surface coverage by magnesium occurring on the substrate at a density of 1.1 × 10(15) atom/cm(2), define a process window, fabrication rules, and limits for DNA-based lithography.

  12. Plastic masters-rigid templates for soft lithography.

    Science.gov (United States)

    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.

  13. A graphical simulation model of the entire DNA process associated with the analysis of short tandem repeat loci.

    Science.gov (United States)

    Gill, Peter; Curran, James; Elliot, Keith

    2005-01-01

    The use of expert systems to interpret short tandem repeat DNA profiles in forensic, medical and ancient DNA applications is becoming increasingly prevalent as high-throughput analytical systems generate large amounts of data that are time-consuming to process. With special reference to low copy number (LCN) applications, we use a graphical model to simulate stochastic variation associated with the entire DNA process starting with extraction of sample, followed by the processing associated with the preparation of a PCR reaction mixture and PCR itself. Each part of the process is modelled with input efficiency parameters. Then, the key output parameters that define the characteristics of a DNA profile are derived, namely heterozygote balance (Hb) and the probability of allelic drop-out p(D). The model can be used to estimate the unknown efficiency parameters, such as pi(extraction). 'What-if' scenarios can be used to improve and optimize the entire process, e.g. by increasing the aliquot forwarded to PCR, the improvement expected to a given DNA profile can be reliably predicted. We demonstrate that Hb and drop-out are mainly a function of stochastic effect of pre-PCR molecular selection. Whole genome amplification is unlikely to give any benefit over conventional PCR for LCN.

  14. Cysteine Metabolism and Oxidative Processes in the Rat Liver and Kidney after Acute and Repeated Cocaine Treatment.

    Directory of Open Access Journals (Sweden)

    Danuta Kowalczyk-Pachel

    Full Text Available The role of cocaine in modulating the metabolism of sulfur-containing compounds in the peripheral tissues is poorly understood. In the present study we addressed the question about the effects of acute and repeated (5 days cocaine (10 mg/kg i.p. administration on the total cysteine (Cys metabolism and on the oxidative processes in the rat liver and kidney. The whole pool of sulfane sulfur, its bound fraction and hydrogen sulfide (H2S were considered as markers of anaerobic Cys metabolism while the sulfate as a measure of its aerobic metabolism. The total-, non-protein- and protein- SH group levels were assayed as indicators of the redox status of thiols. Additionally, the activities of enzymes involved in H2S formation (cystathionine γ-lyase, CSE; 3-mercaptopyruvate sulfurtransferase, 3-MST and GSH metabolism (γ-glutamyl transpeptidase, γ-GT; glutathione S-transferase, GST were determined. Finally, we assayed the concentrations of reactive oxygen species (ROS and malondialdehyde (MDA as markers of oxidative stress and lipid peroxidation, respectively. In the liver, acute cocaine treatment, did not change concentrations of the whole pool of sulfane sulfur, its bound fraction, H2S or sulfate but markedly decreased levels of non-protein SH groups (NPSH, ROS and GST activity while γ-GT was unaffected. In the kidney, acute cocaine significantly increased concentration of the whole pool of sulfane sulfur, reduced the content of its bound fraction but H2S, sulfate and NPSH levels were unchanged while ROS and activities of GST and γ-GT were reduced. Acute cocaine enhanced activity of the CSE and 3-MST in the liver and kidney, respectively. Repeatedly administered cocaine enhanced the whole pool of sulfane sulfur and reduced H2S level simultaneously increasing sulfate content both in the liver and kidney. After repeated cocaine, a significant decrease in ROS was still observed in the liver while in the kidney, despite unchanged ROS content, a marked

  15. Cysteine Metabolism and Oxidative Processes in the Rat Liver and Kidney after Acute and Repeated Cocaine Treatment.

    Science.gov (United States)

    Kowalczyk-Pachel, Danuta; Iciek, Małgorzata; Wydra, Karolina; Nowak, Ewa; Górny, Magdalena; Filip, Małgorzata; Włodek, Lidia; Lorenc-Koci, Elżbieta

    2016-01-01

    The role of cocaine in modulating the metabolism of sulfur-containing compounds in the peripheral tissues is poorly understood. In the present study we addressed the question about the effects of acute and repeated (5 days) cocaine (10 mg/kg i.p.) administration on the total cysteine (Cys) metabolism and on the oxidative processes in the rat liver and kidney. The whole pool of sulfane sulfur, its bound fraction and hydrogen sulfide (H2S) were considered as markers of anaerobic Cys metabolism while the sulfate as a measure of its aerobic metabolism. The total-, non-protein- and protein- SH group levels were assayed as indicators of the redox status of thiols. Additionally, the activities of enzymes involved in H2S formation (cystathionine γ-lyase, CSE; 3-mercaptopyruvate sulfurtransferase, 3-MST) and GSH metabolism (γ-glutamyl transpeptidase, γ-GT; glutathione S-transferase, GST) were determined. Finally, we assayed the concentrations of reactive oxygen species (ROS) and malondialdehyde (MDA) as markers of oxidative stress and lipid peroxidation, respectively. In the liver, acute cocaine treatment, did not change concentrations of the whole pool of sulfane sulfur, its bound fraction, H2S or sulfate but markedly decreased levels of non-protein SH groups (NPSH), ROS and GST activity while γ-GT was unaffected. In the kidney, acute cocaine significantly increased concentration of the whole pool of sulfane sulfur, reduced the content of its bound fraction but H2S, sulfate and NPSH levels were unchanged while ROS and activities of GST and γ-GT were reduced. Acute cocaine enhanced activity of the CSE and 3-MST in the liver and kidney, respectively. Repeatedly administered cocaine enhanced the whole pool of sulfane sulfur and reduced H2S level simultaneously increasing sulfate content both in the liver and kidney. After repeated cocaine, a significant decrease in ROS was still observed in the liver while in the kidney, despite unchanged ROS content, a marked increase

  16. Achieving Low Contact Resistance by Engineering a Metal-Graphene Interface Simply with Optical Lithography.

    Science.gov (United States)

    Kong, Qinghua; Wang, Xuanyun; Xia, Lishuang; Wu, Chenbo; Feng, Zhixin; Wang, Min; Zhao, Jing

    2017-06-28

    High-performance graphene-based transistors crucially depend on the creation of the high-quality graphene-metal contacts. Here we report an approach for achieving ultralow contact resistance simply with optical lithography by engineering a metal-graphene interface. Note that a significant improvement with optical lithography for the contact-treated graphene device leads to a contact resistance as low as 150 Ω·μm. The residue-free sacrificial film impedes the photoresist from further doping graphene, and all of the source and drain contact regions defined by optical lithography remain intact. This approach, being compatible with complementary metal-oxide-semiconductor (CMOS) fabrication processes regardless of the source of graphene, would hold promise for the large-scale production of graphene-based transistors with optical lithography.

  17. Improvement in Lithography Alignment with Thick Aluminum Manufacture Process%厚铝芯片制造工艺的光刻对准效果改善

    Institute of Scientific and Technical Information of China (English)

    马万里

    2011-01-01

    对于厚铝芯片的制造工艺,由于光刻对准标记上覆盖了厚的铝层,对准标记形貌轮廓会变得模糊,这会导致光刻对准出现困难,对偏的问题将变得常见.为了解决此问题,提出了多种改善方法,首先采用叠加标记法,通过将不同层次的对准标记进行叠加,增大了标记的台阶,对准标记的轮廓变得比原来清晰.其次是局部溅射法,通过夹具保护对准标记,确保标记不被厚铝覆盖,因此厚铝将不会对对准标记产生任何影响.最后是剥离工艺法,通过光刻胶保护对准标记,使之不被厚铝覆盖,因此,对准标记形貌将会保持清晰.这些方法在工艺和原理上是不同的,它们适用于不同的环境.通过这些方法,基本可以解决厚铝工艺中光刻对准困难的问题.%For manufacture process with thick aluminum, the profile of alignment mark will become blur because of being covered by thick aluminum. It will lead to have difficulty in photo alignment, and misalignment will be common. For the sake of resolving this problem, several methods are put forward. Firstly, with the alignment mark for overlapping, the step of alignment mark is enlarged by overlapping the marks of different layers. The profile of alignment mark become clear than ever. Secondly, through metal sputtering locally, alignment mark is protected by the clamp from being covered by thick aluminum. So thick aluminum will have no effect on the alignment mark. Finally, by lift off process, photo resistor protects alignment mark from being covered by thick aluminum. So the profile of alignment mark will be clear. These methods are different in process and principle and adapt to different conditions. All of misalignment problem for thick aluminum can be resolved by these methods.

  18. Multi-shaped beam proof of lithography

    Science.gov (United States)

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

    2010-03-01

    In this paper a full package high throughput multi electron-beam approach, called Multi Shaped Beam (MSB), for applications in mask making as well as direct write will be presented including complex proof-of-lithography results. The basic concept enables a significant exposure shot count reduction for advanced patterns compared to standard Variable Shaped Beam (VSB) systems and allows full pattern flexibility by concurrently using MSB, VSB and Cell Projection (CP). Proof of lithography results will be presented, which have been performed using a fully operational electron-beam lithography system including data path and substrate scanning by x/y-stage movement.

  19. Particle Lithography Enables Fabrication of Multicomponent Nanostructures

    Science.gov (United States)

    Lin, Wei-feng; Swartz, Logan A.; Li, Jie-Ren; Liu, Yang; Liu, Gang-yu

    2014-01-01

    Multicomponent nanostructures with individual geometries have attracted much attention because of their potential to carry out multiple functions synergistically. The current work reports a simple method using particle lithography to fabricate multicomponent nanostructures of metals, proteins, and organosiloxane molecules, each with its own geometry. Particle lithography is well-known for its capability to produce arrays of triangular-shaped nanostructures with novel optical properties. This paper extends the capability of particle lithography by combining a particle template in conjunction with surface chemistry to produce multicomponent nanostructures. The advantages and limitations of this approach will also be addressed. PMID:24707328

  20. FEL Applications in EUV Lithography

    CERN Document Server

    Goldstein, M; Shroff, Y A; Silverman, P J; Williams, D

    2005-01-01

    Semiconductor industry growth has largely been made possible by regular improvements in lithography. State of the art lithographic tools cost upwards of twenty five million dollars and use 0.93 numerical aperture projection optics with 193nm wavelengths to pattern features for 45 nm node development. Scaling beyond the 32 nm feature size node is expected to require extreme ultraviolet (EUV) wavelength light. EUV source requirements and equipment industry plasma source development efforts are reviewed. Exploratory research on a novel hybrid klystron and high gain harmonic generation FEL with oblique laser seeding will be disclosed. The opportunity and challenges for FELs to serve as a second generation (year 2011-2013) source technology in the semiconductor industry are presented.

  1. A distance for probability spaces, and long-term values in Markov Decision Processes and Repeated Games

    CERN Document Server

    Renault, Jérôme

    2012-01-01

    Given a finite set $K$, we denote by $X=\\Delta(K)$ the set of probabilities on $K$ and by $Z=\\Delta_f(X)$ the set of Borel probabilities on $X$ with finite support. Studying a Markov Decision Process with partial information on $K$ naturally leads to a Markov Decision Process with full information on $X$. We introduce a new metric $d_*$ on $Z$ such that the transitions become 1-Lipschitz from $(X, \\|.\\|_1)$ to $(Z,d_*)$. In the first part of the article, we define and prove several properties of the metric $d_*$. Especially, $d_*$ satisfies a Kantorovich-Rubinstein type duality formula and can be characterized by using disintegrations. In the second part, we characterize the limit values in several classes of "compact non expansive" Markov Decision Processes. In particular we use the metric $d_*$ to characterize the limit value in Partial Observation MDP with finitely many states and in Repeated Games with an informed controller with finite sets of states and actions. Moreover in each case we can prove the ex...

  2. 4-Nitrobenzene Grafted in Porous Silicon: Application to Optical Lithography.

    Science.gov (United States)

    Tiddia, Mariavitalia; Mula, Guido; Sechi, Elisa; Vacca, Annalisa; Cara, Eleonora; De Leo, Natascia; Fretto, Matteo; Boarino, Luca

    2016-12-01

    In this work, we report a method to process porous silicon to improve its chemical resistance to alkaline solution attacks based on the functionalization of the pore surface by the electrochemical reduction of 4-nitrobenzendiazonium salt. This method provides porous silicon with strong resistance to the etching solutions used in optical lithography and allows the fabrication of tailored metallic contacts on its surface. The samples were studied by chemical, electrochemical, and morphological methods. We demonstrate that the grafted samples show a resistance to harsh alkaline solution more than three orders of magnitude larger than that of pristine porous silicon, being mostly unmodified after about 40 min. The samples maintained open pores after the grafting, making them suitable for further treatments like filling by polymers. Optical lithography was performed on the functionalized samples, and electrochemical characterization results are shown.

  3. Challenges of anamorphic high-NA lithography and mask making

    Science.gov (United States)

    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

  4. Resistless Fabrication of Nanoimprint Lithography (NIL Stamps Using Nano-Stencil Lithography

    Directory of Open Access Journals (Sweden)

    Juergen Brugger

    2013-10-01

    Full Text Available In order to keep up with the advances in nano-fabrication, alternative, cost-efficient lithography techniques need to be implemented. Two of the most promising are nanoimprint lithography (NIL and stencil lithography. We explore here the possibility of fabricating the stamp using stencil lithography, which has the potential for a cost reduction in some fabrication facilities. We show that the stamps reproduce the membrane aperture patterns within ±10 nm and we validate such stamps by using them to fabricate metallic nanowires down to 100 nm in size.

  5. Mask optimization approaches in optical lithography based on a vector imaging model.

    Science.gov (United States)

    Ma, Xu; Li, Yanqiu; Dong, Lisong

    2012-07-01

    Recently, a set of gradient-based optical proximity correction (OPC) and phase-shifting mask (PSM) optimization methods has been developed to solve for the inverse lithography problem under scalar imaging models, which are only accurate for numerical apertures (NAs) of less than approximately 0.4. However, as lithography technology enters the 45 nm realm, immersion lithography systems with hyper-NA (NA>1) are now extensively used in the semiconductor industry. For the hyper-NA lithography systems, the vector nature of the electromagnetic field must be taken into account, leading to the vector imaging models. Thus, the OPC and PSM optimization approaches developed under the scalar imaging models are inadequate to enhance the resolution in immersion lithography systems. This paper focuses on developing pixelated gradient-based OPC and PSM optimization algorithms under a vector imaging model. We first formulate the mask optimization framework, in which the imaging process of the optical lithography system is represented by an integrative and analytic vector imaging model. A gradient-based algorithm is then used to optimize the mask iteratively. Subsequently, a generalized wavelet penalty is proposed to keep a balance between the mask complexity and convergence errors. Finally, a set of methods is exploited to speed up the proposed algorithms.

  6. A novel AX+/BX- paradigm to assess fear learning and safety-signal processing with repeated-measure designs.

    Science.gov (United States)

    Kazama, Andy M; Schauder, Kimberly B; McKinnon, Michael; Bachevalier, Jocelyne; Davis, Michael

    2013-04-15

    One of the core symptoms of anxiety disorders, such as post-traumatic stress disorder, is the failure to overcome feelings of danger despite being in a safe environment. This deficit likely stems from an inability to fully process safety signals, which are cues in the environment that enable healthy individuals to over-ride fear in aversive situations. Studies examining safety signal learning in rodents, humans, and non-human primates currently rely on between-groups designs. Because repeated-measure designs reduce the number of subjects required, and facilitate a broader range of safety signal studies, the current project sought to develop a repeated-measures safety-signal learning paradigm in non-human primates. Twelve healthy rhesus macaques of both sexes received three rounds of auditory fear-potentiated startle training and testing using an AX+/BX- design with all visual cues. Cue AX was paired with an aversive blast of air, whereas the same X cue in compound with another B cue (BX) signaled the absence of an air blast. Hence, cue B served as a safety signal. Once animals consistently discriminated between the aversive (AX+) and safe (BX-) cues, measured by greater startle amplitude in the presence of AX vs. BX, they were tested for conditioned inhibition by eliciting startle in the presence of a novel ambiguous combined cue (AB). Similar to previous AX+/BX- studies, healthy animals rapidly learned to discriminate between the AX+ and BX- cues as well as demonstrate conditioned inhibition in the presence of the combined AB cue (i.e. lower startle amplitude in the presence of AB vs. AX). Additionally, animals performed consistently across three rounds of testing using three new cues each time. The results validate this novel method that will serve as a useful tool for better understanding the mechanisms for the regulation of fear and anxiety. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Imprint lithography advances in LED manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Hershey, Robert; Doyle, Gary; Jones, Chris; LaBrake, Dwayne; Miller, Mike [Molecular Imprints Inc., 1807 West Braker Lane, Building C-11, Austin, TX 78758 (United States)

    2007-07-01

    Imprint lithography is a promising cost effect alternative to e-beam and optical lithography for producing photonic crystals and other nano-scale light extraction and beam directing elements for LEDs; however, there are several challenges that must be overcome before imprint lithography can be applied to typical LED substrates. This paper reviews progress made at Molecular Imprints Inc. (MII) in imprinting representative 3{sup ''} GaN on Sapphire substrates including methods for dealing with substrate non-flatness, multi-die imprint, and imprinting on warped and bowed substrates. The results of imprinting over typical GaN on Sapphire topography and common defects such as fall-on particles and EPI defects is presented along with results on GaN wafers optimized for imprint lithography. Whole wafer thin template replication techniques are also discussed. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  8. Gradient-based inverse extreme ultraviolet lithography.

    Science.gov (United States)

    Ma, Xu; Wang, Jie; Chen, Xuanbo; Li, Yanqiu; Arce, Gonzalo R

    2015-08-20

    Extreme ultraviolet (EUV) lithography is the most promising successor of current deep ultraviolet (DUV) lithography. The very short wavelength, reflective optics, and nontelecentric structure of EUV lithography systems bring in different imaging phenomena into the lithographic image synthesis problem. This paper develops a gradient-based inverse algorithm for EUV lithography systems to effectively improve the image fidelity by comprehensively compensating the optical proximity effect, flare, photoresist, and mask shadowing effects. A block-based method is applied to iteratively optimize the main features and subresolution assist features (SRAFs) of mask patterns, while simultaneously preserving the mask manufacturability. The mask shadowing effect may be compensated by a retargeting method based on a calibrated shadowing model. Illustrative simulations at 22 and 16 nm technology nodes are presented to validate the effectiveness of the proposed methods.

  9. STRUCTURING OF DIAMOND FILMS USING MICROSPHERE LITHOGRAPHY

    Directory of Open Access Journals (Sweden)

    Mária Domonkos

    2014-10-01

    Full Text Available In this study, the structuring of micro- and nanocrystalline diamond thin films is demonstrated. The structuring of the diamond films is performed using the technique of microsphere lithography followed by reactive ion etching. Specifically, this paper presents a four-step fabrication process: diamond deposition (microwave plasma assisted chemical vapor deposition, mask preparation (by the standard Langmuir-Blodgett method, mask modification and diamond etching. A self-assembled monolayer of monodisperse polystyrene (PS microspheres with close-packed ordering is used as the primary template. Then the PS microspheres and the diamond films are processed in capacitively coupled radiofrequency plasma  using different plasma chemistries. This fabrication method illustrates the preparation of large arrays of periodic and homogeneous hillock-like structures. The surface morphology of processed diamond films is characterized by scanning electron microscopy and atomic force microscope. The potential applications of such diamond structures in various fields of nanotechnology are also briefly discussed.

  10. Improvements in anatomy knowledge when utilizing a novel cyclical "Observe-Reflect-Draw-Edit-Repeat" learning process.

    Science.gov (United States)

    Backhouse, Mark; Fitzpatrick, Michael; Hutchinson, Joseph; Thandi, Charankumal S; Keenan, Iain D

    2017-01-01

    Innovative educational strategies can provide variety and enhance student learning while addressing complex logistical and financial issues facing modern anatomy education. Observe-Reflect-Draw-Edit-Repeat (ORDER), a novel cyclical artistic process, has been designed based on cognitivist and constructivist learning theories, and on processes of critical observation, reflection and drawing in anatomy learning. ORDER was initially investigated in the context of a compulsory first year surface anatomy practical (ORDER-SAP) at a United Kingdom medical school in which a cross-over trial with pre-post anatomy knowledge testing was utilized and student perceptions were identified. Despite positive perceptions of ORDER-SAP, medical student (n = 154) pre-post knowledge test scores were significantly greater (P learning methods (3.26, SD = ±2.25) than with ORDER-SAP (2.17, ±2.30). Based on these findings, ORDER was modified and evaluated in the context of an optional self-directed gross anatomy online interactive tutorial (ORDER-IT) for participating first year medical students (n = 55). Student performance was significantly greater (P  0.05) to those students without these characteristics. These findings will be of value to anatomy instructors seeking to engage students from diverse learning backgrounds in a research-led, innovative, time and cost-effective learning method, in the context of contrasting learning environments. Anat Sci Educ 10: 7-22. © 2016 American Association of Anatomists.

  11. Laser microfabrication thin film processes and lithography

    CERN Document Server

    Ehrlich, Daniel J

    1989-01-01

    This book reviews the solid core of fundamental scientific knowledge on laser-stimulated surface chemistry that has accumulated over the past few years. It provides a useful overview for the student and interested non-expert as well as essential reference data (photodissociation cross sections, thermochemical constants, etc.) for the active researcher.

  12. Homogeneity of Residual Layer thickness in UV Nanoimprint Lithography

    Science.gov (United States)

    Hiroshima, Hiroshi; Atobe, Hidemasa

    2009-06-01

    In nanoimprint lithography, control of residual layer thickness is a very important issue. Pattern density variation is inconvenient for nanoimprint lithography but UV nanoimprint is considered more adaptive to pattern density variation thanks to the higher fluidity of UV-curable resin. Despite this consideration, methods to overcome pattern density problems have been developed and adopted in UV nanoimprint lithography. These methods work well; however, it is still remains there a question of whether residual layer thickness uniformity is improved without such methods. In this study, UV nanoimprint is carried out using a conformable contact mechanism, and the impact of pattern density variation and pressing time of nanoimprint on the residual layer profile is investigated for an initially thin UV-curable resin. After recess filling, UV-curable resin moves very locally so as to make the residual layer smoothly change, but does not move sufficiently for the residual layer to be modified across the entire imprint field. For a longer pressing time, the residual layer thickness is decreased only at the edges. A small amount of the UV-curable resin was expelled from the mold, but most was retained between the mold and wafer, and the UV-curable resin moved inward. For realization of a thin and uniform residual layer, the residual layer must be thin throughout the imprint field from the beginning of the pressing process; otherwise the resulting residual layer that is thick only at peripheral regions must be thinned by a long pressing time.

  13. PSM design for inverse lithography with partially coherent illumination.

    Science.gov (United States)

    Ma, Xu; Arce, Gonzalo R

    2008-11-24

    Phase-shifting masks (PSM) are resolution enhancement techniques (RET) used extensively in the semiconductor industry to improve the resolution and pattern fidelity of optical lithography. Recently, a set of gradient-based PSM optimization methods have been developed to solve for the inverse lithography problem under coherent illumination. Most practical lithography systems, however, use partially coherent illumination due to non-zero width and off-axis light sources, which introduce partial coherence factors that must be accounted for in the optimization of PSMs. This paper thus focuses on developing a framework for gradient-based PSM optimization methods which account for the inherent nonlinearities of partially coherent illumination. In particular, the singular value decomposition (SVD) is used to expand the partially coherent imaging equation by eigenfunctions into a sum of coherent systems (SOCS). The first order coherent approximation corresponding to the largest eigenvalue is used in the PSM optimization. In order to influence the solution patterns to have more desirable manufacturability properties and higher fidelity, a post-processing of the mask pattern based on the 2D discrete cosine transformation (DCT) is introduced. Furthermore, a photoresist tone reversing technique is exploited in the design of PSMs to project extremely sparse patterns.

  14. Low Cost Lithography Tool for High Brightness LED Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Andrew Hawryluk; Emily True

    2012-06-30

    The objective of this activity was to address the need for improved manufacturing tools for LEDs. Improvements include lower cost (both capital equipment cost reductions and cost-ofownership reductions), better automation and better yields. To meet the DOE objective of $1- 2/kilolumen, it will be necessary to develop these highly automated manufacturing tools. Lithography is used extensively in the fabrication of high-brightness LEDs, but the tools used to date are not scalable to high-volume manufacturing. This activity addressed the LED lithography process. During R&D and low volume manufacturing, most LED companies use contact-printers. However, several industries have shown that these printers are incompatible with high volume manufacturing and the LED industry needs to evolve to projection steppers. The need for projection lithography tools for LED manufacturing is identified in the Solid State Lighting Manufacturing Roadmap Draft, June 2009. The Roadmap states that Projection tools are needed by 2011. This work will modify a stepper, originally designed for semiconductor manufacturing, for use in LED manufacturing. This work addresses improvements to yield, material handling, automation and throughput for LED manufacturing while reducing the capital equipment cost.

  15. Detection of quasi-periodic processes in repeated measurements: New approach for the fitting and clusterization of different data

    Science.gov (United States)

    Nigmatullin, R.; Rakhmatullin, R.

    2014-12-01

    Many experimentalists were accustomed to think that any independent measurement forms a non-correlated measurement that depends weakly from others. We are trying to reconsider this conventional point of view and prove that similar measurements form a strongly-correlated sequence of random functions with memory. In other words, successive measurements "remember" each other at least their nearest neighbors. This observation and justification on real data help to fit the wide set of data based on the Prony's function. The Prony's decomposition follows from the quasi-periodic (QP) properties of the measured functions and includes the Fourier transform as a partial case. New type of decomposition helps to obtain a specific amplitude-frequency response (AFR) of the measured (random) functions analyzed and each random function contains less number of the fitting parameters in comparison with its number of initial data points. Actually, the calculated AFR can be considered as the generalized Prony's spectrum (GPS), which will be extremely useful in cases where the simple model pretending on description of the measured data is absent but vital necessity of their quantitative description is remained. These possibilities open a new way for clusterization of the initial data and new information that is contained in these data gives a chance for their detailed analysis. The electron paramagnetic resonance (EPR) measurements realized for empty resonator (pure noise data) and resonator containing a sample (CeO2 in our case) confirmed the existence of the QP processes in reality. But we think that the detection of the QP processes is a common feature of many repeated measurements and this new property of successive measurements can attract an attention of many experimentalists. To formulate some general conditions that help to identify and then detect the presence of some QP process in the repeated experimental measurements. To find a functional equation and its solution that

  16. SVM based layout retargeting for fast and regularized inverse lithography

    Institute of Scientific and Technical Information of China (English)

    Kai-sheng LUO; Zheng SHI; Xiao-lang YAN; Zhen GENG

    2014-01-01

    Inverse lithography technology (ILT), also known as pixel-based optical proximity correction (PB-OPC), has shown promising capability in pushing the current 193 nm lithography to its limit. By treating the mask optimization process as an inverse problem in lithography, ILT provides a more complete exploration of the solution space and better pattern fidelity than the tradi-tional edge-based OPC. However, the existing methods of ILT are extremely time-consuming due to the slow convergence of the optimization process. To address this issue, in this paper we propose a support vector machine (SVM) based layout retargeting method for ILT, which is designed to generate a good initial input mask for the optimization process and promote the convergence speed. Supervised by optimized masks of training layouts generated by conventional ILT, SVM models are learned and used to predict the initial pixel values in the‘undefined areas’ of the new layout. By this process, an initial input mask close to the final optimized mask of the new layout is generated, which reduces iterations needed in the following optimization process. Manu-facturability is another critical issue in ILT;however, the mask generated by our layout retargeting method is quite irregular due to the prediction inaccuracy of the SVM models. To compensate for this drawback, a spatial filter is employed to regularize the retargeted mask for complexity reduction. We implemented our layout retargeting method with a regularized level-set based ILT (LSB-ILT) algorithm under partially coherent illumination conditions. Experimental results show that with an initial input mask generated by our layout retargeting method, the number of iterations needed in the optimization process and runtime of the whole process in ILT are reduced by 70.8%and 69.0%, respectively.

  17. Dynamics of hydrogen-producing bacteria in a repeated batch fermentation process using lake sediment as inoculum.

    Science.gov (United States)

    Romano, Stefano; Paganin, Patrizia; Varrone, Cristiano; Tabacchioni, Silvia; Chiarini, Luigi

    2014-02-01

    In this study, we evaluated the effectiveness of lake sediment as inoculum for hydrogen production through dark fermentation in a repeated batch process. In addition, we investigated the effect of heat treatment, applied to enrich hydrogen-producing bacteria, on the bacterial composition and metabolism. Denaturing gradient gel electrophoresis and molecular cloning, both performed using the 16S rDNA gene as target gene, were used to monitor the structure of the bacterial community. Hydrogen production and bacterial metabolism were analysed via gas chromatography and high-performance liquid chromatography. Both treated and non-treated inocula were able to produce high amounts of hydrogen. However, statistical analysis showed a clear difference in their bacterial composition and metabolism. The heat treatment favoured the growth of different Clostridia sp., in particular of Clostridium bifermentans, allowing the production of a constant amount of hydrogen over prolonged time. These cultures showed both butyrate and ethanol fermentation types. Absence of heat treatment allowed species belonging to the genera Bacillus, Sporolactobacillus and Massilia to outgrow Clostridia sp. with a reduction in hydrogen production and a significant metabolic change. Our data indicate that lake sediment harbours bacteria that can efficiently produce hydrogen over prolonged fermentation time. Moreover, we could show that the heat treatment stabilizes the bacterial community composition and the hydrogen production.

  18. Large area nanoimprint by substrate conformal imprint lithography (SCIL)

    Science.gov (United States)

    Verschuuren, Marc A.; Megens, Mischa; Ni, Yongfeng; van Sprang, Hans; Polman, Albert

    2017-06-01

    Releasing the potential of advanced material properties by controlled structuring materials on sub-100-nm length scales for applications such as integrated circuits, nano-photonics, (bio-)sensors, lasers, optical security, etc. requires new technology to fabricate nano-patterns on large areas (from cm2 to 200 mm up to display sizes) in a cost-effective manner. Conventional high-end optical lithography such as stepper/scanners is highly capital intensive and not flexible towards substrate types. Nanoimprint has had the potential for over 20 years to bring a cost-effective, flexible method for large area nano-patterning. Over the last 3-4 years, nanoimprint has made great progress towards volume production. The main accelerator has been the switch from rigid- to wafer-scale soft stamps and tool improvements for step and repeat patterning. In this paper, we discuss substrate conformal imprint lithography (SCIL), which combines nanometer resolution, low patterns distortion, and overlay alignment, traditionally reserved for rigid stamps, with the flexibility and robustness of soft stamps. This was made possible by a combination of a new soft stamp material, an inorganic resist, combined with an innovative imprint method. Finally, a volume production solution will be presented, which can pattern up to 60 wafers per hour.

  19. Semiconductor foundry, lithography, and partners

    Science.gov (United States)

    Lin, Burn J.

    2002-07-01

    The semiconductor foundry took off in 1990 with an annual capacity of less than 0.1M 8-inch-equivalent wafers at the 2-mm node. In 2000, the annual capacity rose to more than 10M. Initially, the technology practiced at foundries was 1 to 2 generations behind that at integrated device manufacturers (IDMs). Presently, the progress in 0.13-mm manufacturing goes hand-in-hand with any of the IDMs. There is a two-order of magnitude rise in output and the progress of technology development outpaces IDMs. What are the reasons of the success? Is it possible to sustain the pace? This paper shows the quick rise of foundries in capacity, sales, and market share. It discusses the their uniqueness which gives rise to advantages in conjunction with challenges. It also shows the role foundries take with their customer partners and supplier partners, their mutual dependencies, as well as expectations. What role then does lithography play in the foundries? What are the lithographic challenges to sustain the pace of technology? The experience of technology development and transfer, at one of the major foundries, is used to illustrate the difficulties and progresses made. Looking into the future, as semiconductor manufacturing will become even more expensive and capital investment more prohibitive, we will make an attempt to suggest possible solutions.

  20. Negative printing by soft lithography.

    Science.gov (United States)

    Ong, Jason Kee Yang; Moore, David; Kane, Jennifer; Saraf, Ravi F

    2014-08-27

    In inkless microcontact printing (IμCP) by soft lithography, the poly(dimethylsiloxane) (PDMS) stamp transfers uncured polymer to a substrate corresponding to its pattern. The spontaneous diffusion of PDMS oligomers to the surface of the stamp that gives rise to this deleterious side effect has been leveraged to fabricate a variety of devices, such as organic thin film transistors, single-electron devices, and biomolecular chips. Here we report an anomalous observation on a partially cured PDMS stamp where the transfer of oligomers onto Au occurred on regions that were not in contact with the stamp, while the surface in contact with the stamp was pristine with no polymer. On the SiO2 surface of the same chip, as expected, the transfer of PDMS occurred exclusively on regions in contact with the stamp. The printing on Au was quantified by a novel method where the submonolayer of PDMS transfer was measured by probing the local electrochemical passivation of the Au. The local transfer of polymer on SiO2 (and also Au) was measured by selective deposition of Au nanoparticle necklaces that exclusively deposited on PDMS at submonolayer sensitivity. It was discovered that the selectivity and sharpness of PDMS deposition on Au for inkless printing (i.e., negative) is significantly better than the traditional (positive) microcontact printing where the stamp is "inked" with low molecular weight PDMS.

  1. Multi-focal multiphoton lithography.

    Science.gov (United States)

    Ritschdorff, Eric T; Nielson, Rex; Shear, Jason B

    2012-03-01

    Multiphoton lithography (MPL) provides unparalleled capabilities for creating high-resolution, three-dimensional (3D) materials from a broad spectrum of building blocks and with few limitations on geometry, qualities that have been key to the design of chemically, mechanically, and biologically functional microforms. Unfortunately, the reliance of MPL on laser scanning limits the speed at which fabrication can be performed, making it impractical in many instances to produce large-scale, high-resolution objects such as complex micromachines, 3D microfluidics, etc. Previously, others have demonstrated the possibility of using multiple laser foci to simultaneously perform MPL at numerous sites in parallel, but use of a stage-scanning system to specify fabrication coordinates resulted in the production of identical features at each focal position. As a more general solution to the bottleneck problem, we demonstrate here the feasibility for performing multi-focal MPL using a dynamic mask to differentially modulate foci, an approach that enables each fabrication site to create independent (uncorrelated) features within a larger, integrated microform. In this proof-of-concept study, two simultaneously scanned foci produced the expected two-fold decrease in fabrication time, and this approach could be readily extended to many scanning foci by using a more powerful laser. Finally, we show that use of multiple foci in MPL can be exploited to assign heterogeneous properties (such as differential swelling) to micromaterials at distinct positions within a fabrication zone.

  2. Array imaging system for lithography

    Science.gov (United States)

    Kirner, Raoul; Mueller, Kevin; Malaurie, Pauline; Vogler, Uwe; Noell, Wilfried; Scharf, Toralf; Voelkel, Reinhard

    2016-09-01

    We present an integrated array imaging system based on a stack of microlens arrays. The microlens arrays are manufactured by melting resist and reactive ion etching (RIE) technology on 8'' wafers (fused silica) and mounted by wafer-level packaging (WLP)1. The array imaging system is configured for 1X projection (magnification m = +1) of a mask pattern onto a planar wafer. The optical system is based on two symmetric telescopes, thus anti-symmetric wavefront aberrations like coma, distortion, lateral color are minimal. Spherical aberrations are reduced by using microlenses with aspherical lens profiles. In our system design approach, sub-images of individual imaging channels do not overlap to avoid interference. Image superposition is achieved by moving the array imaging system during the exposure time. A tandem Koehler integrator illumination system (MO Exposure Optics) is used for illumination. The angular spectrum of the illumination light underfills the pupils of the imaging channels to avoid crosstalk. We present and discuss results from simulation, mounting and testing of a first prototype of the investigated array imaging system for lithography.

  3. Planar self-aligned imprint lithography for coplanar plasmonic nanostructures fabrication

    KAUST Repository

    Wan, Weiwei

    2014-03-01

    Nanoimprint lithography (NIL) is a cost-efficient nanopatterning technology because of its promising advantages of high throughput and high resolution. However, accurate multilevel overlay capability of NIL required for integrated circuit manufacturing remains a challenge due to the high cost of achieving mechanical alignment precision. Although self-aligned imprint lithography was developed to avoid the need of alignment for the vertical layered structures, it has limited usage in the manufacture of the coplanar structures, such as integrated plasmonic devices. In this paper, we develop a new process of planar self-alignment imprint lithography (P-SAIL) to fabricate the metallic and dielectric structures on the same plane. P-SAIL transfers the multilevel imprint processes to a single-imprint process which offers higher efficiency and less cost than existing manufacturing methods. Such concept is demonstrated in an example of fabricating planar plasmonic structures consisting of different materials. © 2014 Springer-Verlag Berlin Heidelberg.

  4. Metal hierarchical patterning by direct nanoimprint lithography.

    Science.gov (United States)

    Radha, Boya; Lim, Su Hui; Saifullah, Mohammad S M; Kulkarni, Giridhar U

    2013-01-01

    Three-dimensional hierarchical patterning of metals is of paramount importance in diverse fields involving photonics, controlling surface wettability and wearable electronics. Conventionally, this type of structuring is tedious and usually involves layer-by-layer lithographic patterning. Here, we describe a simple process of direct nanoimprint lithography using palladium benzylthiolate, a versatile metal-organic ink, which not only leads to the formation of hierarchical patterns but also is amenable to layer-by-layer stacking of the metal over large areas. The key to achieving such multi-faceted patterning is hysteretic melting of ink, enabling its shaping. It undergoes transformation to metallic palladium under gentle thermal conditions without affecting the integrity of the hierarchical patterns on micro- as well as nanoscale. A metallic rice leaf structure showing anisotropic wetting behavior and woodpile-like structures were thus fabricated. Furthermore, this method is extendable for transferring imprinted structures to a flexible substrate to make them robust enough to sustain numerous bending cycles.

  5. Sequestration of DROSHA and DGCR8 by Expanded CGG RNA Repeats Alters MicroRNA Processing in Fragile X-Associated Tremor/Ataxia Syndrome

    Directory of Open Access Journals (Sweden)

    Chantal Sellier

    2013-03-01

    Full Text Available Fragile X-associated tremor/ataxia syndrome (FXTAS is an inherited neurodegenerative disorder caused by the expansion of 55–200 CGG repeats in the 5′ UTR of FMR1. These expanded CGG repeats are transcribed and accumulate in nuclear RNA aggregates that sequester one or more RNA-binding proteins, thus impairing their functions. Here, we have identified that the double-stranded RNA-binding protein DGCR8 binds to expanded CGG repeats, resulting in the partial sequestration of DGCR8 and its partner, DROSHA, within CGG RNA aggregates. Consequently, the processing of microRNAs (miRNAs is reduced, resulting in decreased levels of mature miRNAs in neuronal cells expressing expanded CGG repeats and in brain tissue from patients with FXTAS. Finally, overexpression of DGCR8 rescues the neuronal cell death induced by expression of expanded CGG repeats. These results support a model in which a human neurodegenerative disease originates from the alteration, in trans, of the miRNA-processing machinery.

  6. Sequestration of DROSHA and DGCR8 by expanded CGG RNA repeats alters microRNA processing in fragile X-associated tremor/ataxia syndrome.

    Science.gov (United States)

    Sellier, Chantal; Freyermuth, Fernande; Tabet, Ricardos; Tran, Tuan; He, Fang; Ruffenach, Frank; Alunni, Violaine; Moine, Herve; Thibault, Christelle; Page, Adeline; Tassone, Flora; Willemsen, Rob; Disney, Matthew D; Hagerman, Paul J; Todd, Peter K; Charlet-Berguerand, Nicolas

    2013-03-28

    Fragile X-associated tremor/ataxia syndrome (FXTAS) is an inherited neurodegenerative disorder caused by the expansion of 55-200 CGG repeats in the 5' UTR of FMR1. These expanded CGG repeats are transcribed and accumulate in nuclear RNA aggregates that sequester one or more RNA-binding proteins, thus impairing their functions. Here, we have identified that the double-stranded RNA-binding protein DGCR8 binds to expanded CGG repeats, resulting in the partial sequestration of DGCR8 and its partner, DROSHA, within CGG RNA aggregates. Consequently, the processing of microRNAs (miRNAs) is reduced, resulting in decreased levels of mature miRNAs in neuronal cells expressing expanded CGG repeats and in brain tissue from patients with FXTAS. Finally, overexpression of DGCR8 rescues the neuronal cell death induced by expression of expanded CGG repeats. These results support a model in which a human neurodegenerative disease originates from the alteration, in trans, of the miRNA-processing machinery.

  7. Nanoimprint lithography for green water-repellent film derived from biomass with high-light transparency

    Science.gov (United States)

    Takei, Satoshi; Hanabata, Makoto

    2015-03-01

    Newly eco-friendly high light transparency film with plant-based materials was investigated to future development of liquid crystal displays and optical devices with water repellency as a chemical design concept of nanoimprint lithography. This procedure is proven to be suitable for material design and the process conditions of ultraviolet curing nanoimprint lithography for green water-repellent film derived from biomass with high-light transparency. The developed formulation of advanced nanoimprinted materials design derived from lactulose and psicose, and the development of suitable UV nanoimprint conditions produced high resolutions of the conical shaped moth-eye regularly-nanostructure less than approximately 200 nm diameter, and acceptable patterning dimensional accuracy by the replication of 100 times of UV nanoimprint lithography cycles. The newly plant-based materials and the process conditions are expected as one of the defect less nanoimprint lithographic technologies in next generation electronic devices.

  8. Conserved leucines in N-terminal heptad repeat HR1 of envelope fusion protein F of group II nucleopolyhedroviruses are important for correct processing and essential for fusogenicity

    NARCIS (Netherlands)

    Long, G.; Pan, X.; Vlak, J.M.

    2008-01-01

    The heptad repeat (HR), a conserved structural motif of class I viral fusion proteins, is responsible for the formation of a six-helix bundle structure during the envelope fusion process. The insect baculovirus F protein is a newly found budded virus envelope fusion protein which possesses common fe

  9. Scanning near-field lithography with high precision flexure orientation stage control

    Science.gov (United States)

    Qin, Jin; Zhang, Liang; Tan, Haosen; Wang, Liang

    2017-09-01

    A new design of an orientation stage for scanning near-field lithography is presented based on flexure hinges. Employing flexure mechanisms in place of rigid-body mechanisms is one of the most promising techniques to efficiently implement high precision motion and avoid problems caused by friction. For near-field scanning lithography with evanescent wave, best resolution can be achieved in contact mode. However, if the mask is fixed on a rigid stage, contact friction will deteriorate the lithography surface. To reduce friction while maintaining good contact between the mask and the substrate, the mask should be held with high lateral stiffness and low torsion stiffness. This design can hold the mask in place during the scanning process and achieve passive alignment. Circular flexure hinges, whose parameters are determined by motion requirements based on Schotborgh's equation, are used as the basic unit of the stage to achieve passive alignment by compensating motions from elastic deformation. A finite-element analysis is performed to verify this property of the stage. With the aid of this stage, 21 nm resolution is achieved in static near-field lithography and 18 nm line-width in scanning near-field lithography.

  10. Surface force measurement of ultraviolet nanoimprint lithography materials

    Science.gov (United States)

    Taniguchi, Jun; Hasegawa, Masayuki; Amemiya, Hironao; Kobayashi, Hayato

    2016-02-01

    Ultraviolet nanoimprint lithography (UV-NIL) has advantages such as room-temperature operation, high through-put, and high resolution. In the UV-NIL process, the mold needs a release coating material to prevent adhesion of the transfer resin. Usually, fluorinated silane coupling agents are used as release coating materials. To evaluate the release property, surface force analyzer equipment was used. This equipment can measure the surface forces between release-coated or noncoated mold material surfaces and UV-cured resin surfaces in the solid state. Lower surface forces were measured when a release coating was used on the mold material surface.

  11. Antireflective surface patterned by rolling mask lithography

    Science.gov (United States)

    Seitz, Oliver; Geddes, Joseph B.; Aryal, Mukti; Perez, Joseph; Wassei, Jonathan; McMackin, Ian; Kobrin, Boris

    2014-03-01

    A growing number of commercial products such as displays, solar panels, light emitting diodes (LEDs and OLEDs), automotive and architectural glass are driving demand for glass with high performance surfaces that offer anti-reflective, self-cleaning, and other advanced functions. State-of-the-art coatings do not meet the desired performance characteristics or cannot be applied over large areas in a cost-effective manner. "Rolling Mask Lithography" (RML™) enables highresolution lithographic nano-patterning over large-areas at low-cost and high-throughput. RML is a photolithographic process performed using ultraviolet (UV) illumination transmitted through a soft cylindrical mask as it rolls across a substrate. Subsequent transfer of photoresist patterns into the substrate is achieved using an etching process, which creates a nanostructured surface. The current generation exposure tool is capable of patterning one-meter long substrates with a width of 300 mm. High-throughput and low-cost are achieved using continuous exposure of the resist by the cylindrical photomask. Here, we report on significant improvements in the application of RML™ to fabricate anti-reflective surfaces. Briefly, an optical surface can be made antireflective by "texturing" it with a nano-scale pattern to reduce the discontinuity in the index of refraction between the air and the bulk optical material. An array of cones, similar to the structure of a moth's eye, performs this way. Substrates are patterned using RML™ and etched to produce an array of cones with an aspect ratio of 3:1, which decreases the reflectivity below 0.1%.

  12. Metamaterial fishnet structure formed from nanoimprint lithography

    Science.gov (United States)

    Sharp, Graham J.; Yuce, Murat; Hu, Xiaolon; Sinworapun, Mantana; Khokhar, Ali Z.; Johnson, Nigel P.

    2013-05-01

    We report on the fabrication and characterisation of fishnet structures of various dimensions on a polymer layer. The fabrication process causes metal-dielectric-metal rectangular pillars to be compressed to the bottom of fishnet structures. The metamaterial structures are fabricated using nanoimprint lithography, allowing large areas to be patterned quickly and good reproducibility through multiple use of the nanoimprint stamp. A tri-layer comprising of silver (Ag) and magnesium fluoride (MgF2) was deposited on a thick polymer layer, in this instance PMMA, before being directly imprinted by a stamp. When the metal-dielectric layered pillars are imprinted to a sufficient depth in the PMMA below the fishnet, distinct resonance peaks can be measured at both visible and near-infrared frequencies. The precise wavelength of the resonant peak at near-infrared and its Q-factor can be changed by altering the physical dimensions and number of metal and dielectric layers of the fishnet respectively. The response viewed at visible frequencies is due to the pillars that sit in the PMMA, below the fishnet. Silver and magnesium fluoride layers that comprise the suppressed pillars are crushed during the imprinting process but still allow for light to be transmitted. Despite imprinting directly into multiple metal and dielectric layers, high quality structures are observed with a minimum feature size as low as 200 nm. Resonance peaks are measured experimentally in reflectance using an FTIR spectrometer with a calcium fluoride (CaF2) beam-splitter and a visible wavelength range spectrometer with a silicon (Si) detector.

  13. Double-Sided Opportunities Using Chemical Lift-Off Lithography.

    Science.gov (United States)

    Andrews, Anne M; Liao, Wei-Ssu; Weiss, Paul S

    2016-08-16

    We discuss the origins, motivation, invention, development, applications, and future of chemical lift-off lithography, in which a specified pattern of a self-assembled monolayer is removed, i.e., lifted off, using a reactive, patterned stamp that is brought into contact with the monolayer. For Au substrates, this process produces a supported, patterned monolayer of Au on the stamp in addition to the negative pattern in the original molecular monolayer. Both the patterned molecular monolayer on the original substrate and the patterned supported metal monolayer on the stamp are useful as materials and for further applications in sensing and other areas. Chemical lift-off lithography effectively lowers the barriers to and costs of high-resolution, large-area nanopatterning. On the patterned monolayer side, features in the single-nanometer range can be produced across large (square millimeter or larger) areas. Patterns smaller than the original stamp feature sizes can be produced by controlling the degree of contact between the stamp and the lifted-off monolayer. We note that this process is different than conventional lift-off processes in lithography in that chemical lift-off lithography removes material, whereas conventional lift-off is a positive-tone patterning method. Chemical lift-off lithography is in some ways similar to microtransfer printing. Chemical lift-off lithography has critical advantages in the preparation of biocapture surfaces because the molecules left behind are exploited to space and to orient functional(ized) molecules. On the supported metal monolayer side, a new two-dimensional material has been produced. The useful important chemical properties of Au (vis-à-vis functionalization with thiols) are retained, but the electronic and optical properties of bulk Au or even Au nanoparticles are not. These metal monolayers do not quench excitation and may be useful in optical measurements, particularly in combination with selective binding due to

  14. Enhancement of superconductivity in NbN nanowires by negative electron-beam lithography with positive resist

    Science.gov (United States)

    Charaev, I.; Silbernagel, T.; Bachowsky, B.; Kuzmin, A.; Doerner, S.; Ilin, K.; Semenov, A.; Roditchev, D.; Vodolazov, D. Yu.; Siegel, M.

    2017-08-01

    We performed comparative experimental investigation of superconducting NbN nanowires which were prepared by means of positive- and negative electron-beam lithography with the same positive tone Poly-methyl-methacrylate (PMMA) resist. We show that nanowires with a thickness 4.9 nm and widths less than 100 nm demonstrate at 4.2 K higher critical temperature and higher density of critical and retrapping currents when they are prepared by negative lithography. Also the ratio of the experimental critical current to the depairing critical current is larger for nanowires prepared by negative lithography. We associate the observed enhancement of superconducting properties with the difference in the degree of damage that nanowire edges sustain in the lithographic process. A whole range of advantages which is offered by the negative lithography with positive PMMA resist ensures high potential of this technology for improving the performance metrics of superconducting nanowire singe-photon detectors.

  15. Automatic layout feature extraction for lithography hotspot detection based on deep neural network

    Science.gov (United States)

    Matsunawa, Tetsuaki; Nojima, Shigeki; Kotani, Toshiya

    2016-03-01

    Lithography hotspot detection in the physical verification phase is one of the most important techniques in today's optical lithography based manufacturing process. Although lithography simulation based hotspot detection is widely used, it is also known to be time-consuming. To detect hotspots in a short runtime, several machine learning based methods have been proposed. However, it is difficult to realize highly accurate detection without an increase in false alarms because an appropriate layout feature is undefined. This paper proposes a new method to automatically extract a proper layout feature from a given layout for improvement in detection performance of machine learning based methods. Experimental results show that using a deep neural network can achieve better performance than other frameworks using manually selected layout features and detection algorithms, such as conventional logistic regression or artificial neural network.

  16. Multiple processing of Ig-Hepta/GPR116, a G protein-coupled receptor with immunoglobulin (Ig)-like repeats, and generation of EGF2-like fragment.

    Science.gov (United States)

    Fukuzawa, Taku; Hirose, Shigehisa

    2006-09-01

    Ig-Hepta/GPR116 is a member of the LNB-TM7 subfamily of G protein-coupled receptors (GPCRs), also termed the adhesion GPCRs, whose members have EGF, cadherin, lectin, thrombospondin, or Ig repeats in their long N-terminus. In this study, we established that Ig-Hepta is processed at multiple sites yielding the following four fragments: (i) presequence (amino acid residues 1-24), (ii) proEGF2 (25-223, alpha-fragment), (iii) Ig repeats (224-993, beta-chain), and (iv) TM7 (994-1349, gamma-chain). The proEGF2 region is converted to EGF2 (52-223) by the processing enzyme furin and remains attached to the beta- and gamma-chains. Expression of some mRNA species was affected by the presence of alpha-fragment. These results suggest that the furin-processed alpha-fragment is involved in cellular signaling.

  17. Simultaneous fabrication of line defects-embedded periodic lattice by topographically assisted holographic lithography

    Science.gov (United States)

    2011-01-01

    We have demonstrated simultaneous fabrication of designed defects within a periodic structure. For rapid fabrication of periodic structures incorporating nanoscale line-defects at large area, topographically assisted holographic lithography (TAHL) technique, combining the strength of hologram lithography and phase-shift interference, was proposed. Hot-embossing method generated the photoresist patterns with vertical side walls which enabled phase-shift mask effect at the edge of patterns. Embossing temperature and relief height were crucial parameters for the successful TAHL process. Periodic holes with a diameter of 600 nm at a 1 μm-pitch incorporating 250 nm wide line-defects were obtained simultaneously. PMID:21749704

  18. Simultaneous fabrication of line defects-embedded periodic lattice by topographically assisted holographic lithography

    Directory of Open Access Journals (Sweden)

    Kim Ki Seok

    2011-01-01

    Full Text Available Abstract We have demonstrated simultaneous fabrication of designed defects within a periodic structure. For rapid fabrication of periodic structures incorporating nanoscale line-defects at large area, topographically assisted holographic lithography (TAHL technique, combining the strength of hologram lithography and phase-shift interference, was proposed. Hot-embossing method generated the photoresist patterns with vertical side walls which enabled phase-shift mask effect at the edge of patterns. Embossing temperature and relief height were crucial parameters for the successful TAHL process. Periodic holes with a diameter of 600 nm at a 1 μm-pitch incorporating 250 nm wide line-defects were obtained simultaneously.

  19. NANOIMPRINT LITHOGRAPHY TECHNOLOGY WITH AUTOMATIC ALIGNMENT

    Institute of Scientific and Technical Information of China (English)

    FAN Xiqiu; ZHANG Honghai; WANG Xuefang; HU Xiaofeng; JIA Ke; LIU Sheng

    2007-01-01

    Nanoimprint lithography (NIL) is recognized as one of the most promising candidates for the next generation lithography (NGL) to obtain sub-100 nm patterns because of its simplicity,high-throughput and low-cost. While substantial effort has been expending on NIL for producing smaller and smaller feature sizes, considerably less effort has been devoted to the equally important issue-alignment between template and substrate. A homemade prototype nanoimprint lithography enable the substrate to move towards the desired position automatically. Linear motors with 300 mm travel range and 1 μm step resolution are used as macro actuators, and piezoelectric translators with 50 μm travel range and 1 nm step resolution are used as micro actuators. In addition, the prototype provides one translation (z displacement) and two tilting motion(α and β) to automatically bring uniform intact contact between the template and substrate surfaces by using a flexure stage. As a result, 10 μm coarse alignment accuracy and 20 nm fine alignment accuracy can be achieved. Finally,some results of nanostructures and micro devices such as nanoscale trenches and holes, gratings and microlens array fabricated using the prototype tool are presented, and hot embossing lithography, one typical NIL technology, are depicted by taking nanoscale gratings fabrication as an example.

  20. Solvent-vapor-assisted imprint lithography

    NARCIS (Netherlands)

    Voicu, Nicoleta E.; Ludwigs, Sabine; Crossland, Edward J. W.; Andrew, Piers; Steiner, Ullrich

    2007-01-01

    Sub-micrometer features are replicated into high-molecular-weight polymer resists by using solvent-assisted nanoimprint lithography (see figure). By swelling the polymer in a controlled solvent-vapor atmosphere, millibar pressures and ambient temperatures are sufficient to achieve high-fidelity

  1. Thermoplastic microcantilevers fabricated by nanoimprint lithography

    DEFF Research Database (Denmark)

    Greve, Anders; Keller, Stephan Urs; Vig, Asger Laurberg

    2010-01-01

    Nanoimprint lithography has been exploited to fabricate micrometre-sized cantilevers in thermoplastic. This technique allows for very well defined microcantilevers and gives the possibility of embedding structures into the cantilever surface. The microcantilevers are fabricated in TOPAS and are up...

  2. Fabrication of biopolymer cantilevers using nanoimprint lithography

    DEFF Research Database (Denmark)

    Keller, Stephan Sylvest; Feidenhans'l, Nikolaj Agentoft; Fisker-Bødker, Nis

    2011-01-01

    The biodegradable polymer poly(l-lactide) (PLLA) was introduced for the fabrication of micromechanical devices. For this purpose, thin biopolymer films with thickness around 10 μm were spin-coated on silicon substrates. Patterning of microcantilevers is achieved by nanoimprint lithography. A major...

  3. Extreme ultraviolet lithography: reflective mask technology

    Science.gov (United States)

    Walton, Christopher C.; Kearney, Patrick A.; Mirkarimi, Paul B.; Bowers, Joel M.; Cerjan, Charles J.; Warrick, Abbie L.; Wilhelmsen, Karl C.; Fought, Eric R.; Moore, Craig E.; Larson, Cindy C.; Baker, Sherry L.; Burkhart, Scott C.; Hector, Scott D.

    2000-07-01

    EUVL mask blanks consist of a distributed Bragg reflector made of 6.7 nm-pitch bi-layers of Mo and Si deposited upon a precision Si or glass substrate. The layer deposition process has been optimized for low defects, by application of a vendor-supplied but highly modified ion-beam sputter deposition system. This system is fully automated using SMIF technology to obtain the lowest possible environmental- and handling-added defect levels. Originally designed to coat 150 mm substrates, it was upgraded in July 1999 to 200 mm and has coated runs of over 50 substrates at a time with median added defects > 100 nm below 0.05/cm2. These improvements have resulted from a number of ion-beam sputter deposition system modifications, upgrades, and operational changes, which will be discussed. Success in defect reduction is highly dependent upon defect detection, characterization, and cross- platform positional registration. We have made significant progress in adapting and extending commercial tools to this purpose, and have identified the surface scanner detection limits for different defect classes, and the signatures of false counts and non-printable scattering anomalies on the mask blank. We will present key results and how they have helped reduce added defects. The physics of defect reduction and mitigation is being investigated by a program on multilayer growth over deliberately placed perturbations (defects) of varying size. This program includes modeling of multilayer growth and modeling of defect printability. We developed a technique for depositing uniformly sized gold spheres on EUVL substrates, and have studied the suppression of the perturbations during multilayer growth under varying conditions. This work is key to determining the lower limit of critical defect size for EUV Lithography. We present key aspects of this work. We will summarize progress in all aspects of EUVL mask blank development, and present detailed results on defect reduction and mask blank

  4. Extreme Ultraviolet Lithography - Reflective Mask Technology

    Energy Technology Data Exchange (ETDEWEB)

    Walton, C.C.; Kearney, P.A.; Mirkarimi, P.B.; Bowers, J.M.; Cerjan, C.; Warrick, A.L.; Wilhelmsen, K.; Fought, E.; Moore, C.; Larson, C.; Baker, S.; Burkhart, S.C.; Hector, S.D.

    2000-05-09

    EUVL mask blanks consist of a distributed Bragg reflector made of 6.7nm-pitch bi-layers of MO and Si deposited upon a precision Si or glass substrate. The layer deposition process has been optimized for low defects, by application of a vendor-supplied but highly modified ion-beam sputter deposition system. This system is fully automated using SMIF technology to obtain the lowest possible environmental- and handling-added defect levels. Originally designed to coat 150mm substrates, it was upgraded in July, 1999 to 200 mm and has coated runs of over 50 substrates at a time with median added defects >100nm below 0.05/cm{sup 2}. These improvements have resulted from a number of ion-beam sputter deposition system modifications, upgrades, and operational changes, which will be discussed. Success in defect reduction is highly dependent upon defect detection, characterization, and cross-platform positional registration. We have made significant progress in adapting and extending commercial tools to this purpose, and have identified the surface scanner detection limits for different defect classes, and the signatures of false counts and non-printable scattering anomalies on the mask blank. We will present key results and how they have helped reduce added defects. The physics of defect reduction and mitigation is being investigated by a program on multilayer growth over deliberately placed perturbations (defects) of varying size. This program includes modeling of multilayer growth and modeling of defect printability. We developed a technique for depositing uniformly sized gold spheres on EUVL substrates, and have studied the suppression of the perturbations during multilayer growth under varying conditions. This work is key to determining the lower limit of critical defect size for EUV Lithography. We present key aspects of this work. We will summarize progress in all aspects of EUVL mask blank development, and present detailed results on defect reduction and mask blank

  5. Integration of plant viruses in electron beam lithography nanostructures

    Science.gov (United States)

    Alonso, Jose M.; Ondarçuhu, Thierry; Bittner, Alexander M.

    2013-03-01

    Tobacco mosaic virus (TMV) is the textbook example of a virus, and also of a self-assembling nanoscale structure. This tubular RNA/protein architecture has also found applications as biotemplate for the synthesis of nanomaterials such as wires, as tubes, or as nanoparticle assemblies. Although TMV is, being a biological structure, quite resilient to environmental conditions (temperature, chemicals), it cannot be processed in electron beam lithography (eBL) fabrication, which is the most important and most versatile method of nanoscale structuring. Here we present adjusted eBL-compatible processes that allow the incorporation of TMV in nanostructures made of positive and negative tone eBL resists. The key steps are covering TMV by polymer resists, which are only heated to 50 °C, and development (selective dissolution) in carefully selected organic solvents. We demonstrate the post-lithography biochemical functionality of TMV by selective immunocoating of the viral particles, and the use of immobilized TMV as direct immunosensor. Our modified eBL process should be applicable to incorporate a wide range of sensitive materials in nanofabrication schemes.

  6. Computer numerical control (CNC) lithography: light-motion synchronized UV-LED lithography for 3D microfabrication

    Science.gov (United States)

    Kim, Jungkwun; Yoon, Yong-Kyu; Allen, Mark G.

    2016-03-01

    This paper presents a computer-numerical-controlled ultraviolet light-emitting diode (CNC UV-LED) lithography scheme for three-dimensional (3D) microfabrication. The CNC lithography scheme utilizes sequential multi-angled UV light exposures along with a synchronized switchable UV light source to create arbitrary 3D light traces, which are transferred into the photosensitive resist. The system comprises a switchable, movable UV-LED array as a light source, a motorized tilt-rotational sample holder, and a computer-control unit. System operation is such that the tilt-rotational sample holder moves in a pre-programmed routine, and the UV-LED is illuminated only at desired positions of the sample holder during the desired time period, enabling the formation of complex 3D microstructures. This facilitates easy fabrication of complex 3D structures, which otherwise would have required multiple manual exposure steps as in the previous multidirectional 3D UV lithography approach. Since it is batch processed, processing time is far less than that of the 3D printing approach at the expense of some reduction in the degree of achievable 3D structure complexity. In order to produce uniform light intensity from the arrayed LED light source, the UV-LED array stage has been kept rotating during exposure. UV-LED 3D fabrication capability was demonstrated through a plurality of complex structures such as V-shaped micropillars, micropanels, a micro-‘hi’ structure, a micro-‘cat’s claw,’ a micro-‘horn,’ a micro-‘calla lily,’ a micro-‘cowboy’s hat,’ and a micro-‘table napkin’ array.

  7. Influence of domestication process on immune response to repeated emersion stressors in Eurasian perch (Perca fluviatilis, L.).

    Science.gov (United States)

    Douxfils, J; Lambert, S; Mathieu, C; Milla, S; Mandiki, S N M; Henrotte, E; Wang, N; Dieu, M; Raes, M; Rougeot, C; Kestemont, P

    2014-03-25

    Domestication might be a possible way to reduce the physiological response to long-term stressors and deleterious effects on immunity. The present study aimed to evaluate the chronic immune response induced by repeated emersions and the possible impact of domestication by comparing farmed Eurasian perch with short (F1) and long (F4) captive-life history. In the first experiment, fish were exposed to a single emersion and physiological stress response was measured in the short term to characterize fish sensitivity to the tested stressor. Serum cortisol and glucose elevated within 6h post-stress and splenosomatic index (SSI) decreased within 48h, indicating that the species was affected by emersion stressor. In the second experiment, F1 and F4 generations were submitted to repeated water emersions (3 times/week during 44days). On day 9, 18 and 44, samplings were performed 48h post-stressor to highlight any sustained disruption of immune system. Serum cortisol, glucose, SSI and lysozyme activity were evaluated and serum proteome was analyzed using 2D-DIGE. Any of the tested variables were affected by repeated emersions and proteomic analysis only revealed that alpha-2 macroglobulins (a2Ms) were up-regulated in the serum of stressed individuals. Domestication also resulted in the up-regulation of five a2M isoforms and down-regulation of complement C3 and Ig light chain proteins, independently of any stressor exposure. In conclusion, the results suggested that repeated emersions are not severe stressors for Eurasian perch, probably explaining why domestication had no influence on fish responses. Changes associated with domestication are highly complex and certainly need further investigations.

  8. Evaluation of nanoimprint lithography as a fabrication method of distributed feedback laser diodes

    Energy Technology Data Exchange (ETDEWEB)

    Yanagisawa, M; Tsuji, Y; Yoshinaga, H; Hiratsuka, K [Transmission Devices R and D Laboratories, Sumitomo Electric Industries, LTD., 1, Taya-cho, Sakae-ku, Yokohama, 244-8588 Kanagawa (Japan); Taniguchi, J, E-mail: myanagsw@sei.co.j [Faculty of Industrial Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, 278-8510 Chiba (Japan)

    2009-11-15

    We have succeeded in employing nanoimprint lithography (NIL) to form the diffraction gratings of distributed feedback laser diodes (DFB LDs) used in optical communication. Uniform gratings and phase-shifted gratings with periods of 232 nm have been formed by using a reverse NIL with a step-and-repeat imprint tool. Line edge roughness has been sufficiently low with the fabricated gratings. DFB LDs fabricated by NIL have indicated comparable characteristics with LDs fabricated by electron beam lithography. We have also demonstrated that phase-shifted DFB LDs show better uniformity in characteristics than uniform-grating DFB LDs. The results of this study indicate that NIL has high potential for the fabrication of DFB LDs.

  9. High resolution 100 kV electron beam lithography in SU-8

    DEFF Research Database (Denmark)

    Olsen, Brian Bilenberg; Jakobsen, S.; Schmidt, M.S.

    2006-01-01

    High resolution 100 kV electron beam lithography in thin layers of the negative resist SU-8 is demonstrated. Sub-30 nm lines with a pitch down to 300 nm are written in 100 nm thick SU-8. Two reactive ion etch processes are developed in order to transfer the SU-8 structures into a silicon substrat...

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

    Science.gov (United States)

    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…

  11. Microfluidic structures for LOC devices designed by laser lithography

    Science.gov (United States)

    Figurova, M.; Pudis, D.; Gaso, P.

    2016-12-01

    Nowadays, lab on a chip (LOC) applications are very popular in the field of biomedicine. LOC device works with biological materials and enables to arrange conventional laboratory operations on a small chip. Philosophy of LOC applications stands on quick and precise diagnostics process and technology, which uses cheap materials with possibility of rapid prototyping. LOC, as a time saving application, works with small volume of samples and reagents and enables better control over the sample. We present fabrication method of functional LOC chip for different biomedical microfluidic applications based on direct laser writing (DLW) lithography. We present fabrication of few types of microfluidic and micro-optic structures with different capabilities created by DLW system. The combination of DLW lithography in photoresist layer deposited on glass substrate and polydimethylsiloxane (PDMS) replica molding process were used for patterning of designed microstructures. Prepared microfluidic and micro-optic structures were observed by confocal microscope and microfluidic flow observations were investigated by conventional optical microscope and CCD camera.

  12. Stop flow lithography in perfluoropolyether (PFPE) microfluidic channels.

    Science.gov (United States)

    Bong, Ki Wan; Lee, Jiseok; Doyle, Patrick S

    2014-12-21

    Stop Flow Lithography (SFL) is a microfluidic-based particle synthesis method for creating anisotropic multifunctional particles with applications that range from MEMS to biomedical engineering. Polydimethylsiloxane (PDMS) has been typically used to construct SFL devices as the material enables rapid prototyping of channels with complex geometries, optical transparency, and oxygen permeability. However, PDMS is not compatible with most organic solvents which limit the current range of materials that can be synthesized with SFL. Here, we demonstrate that a fluorinated elastomer, called perfluoropolyether (PFPE), can be an alternative oxygen permeable elastomer for SFL microfluidic flow channels. We fabricate PFPE microfluidic devices with soft lithography and synthesize anisotropic multifunctional particles in the devices via the SFL process--this is the first demonstration of SFL with oxygen lubrication layers in a non-PDMS channel. We benchmark the SFL performance of the PFPE devices by comparing them to PDMS devices. We synthesized particles in both PFPE and PDMS devices under the same SFL conditions and found the difference of particle dimensions was less than a micron. PFPE devices can greatly expand the range of precursor materials that can be processed in SFL because the fluorinated devices are chemically resistant to most organic solvents, an inaccessible class of reagents in PDMS-based devices due to swelling.

  13. Lithography focus/exposure control and corrections to improve CDU

    Science.gov (United States)

    Kim, Young Ki; Yelverton, Mark; Lee, Joungchel; Cheng, Jerry; Wei, Hong; Kim, Jeong Soo; Gutjahr, Karsten; Gao, Jie; Karur-Shanmugam, Ram; Herrera, Pedro; Huang, Kevin; Volkovich, Roie; Pierson, Bill

    2013-04-01

    As leading edge lithography moves to advanced nodes which requires better critical dimension (CD) control ability within wafer. Current methods generally make exposure corrections by field via factory automation or by sub-recipe to improve CD uniformity. KLA-Tencor has developed a method to provide CD uniformity (CDU) control using a generated Focus/Exposure (F/E) model from a representative process. Exposure corrections by each field can be applied back to the scanner so as to improve CD uniformity through the factory automation. CDU improvement can be observed either at after lithography or after etch metrology steps. In addition to corrections, the graphic K-T Analyzer interface also facilitates the focus/exposure monitoring at the extreme wafer edge. This paper will explain the KT CDFE method and the application in production environment. Run to run focus/exposure monitoring will be carried out both on monitoring and production wafers to control the wafer process and/or scanner fleet. CDU improvement opportunities will be considered as well.

  14. Deployment Repeatability

    Science.gov (United States)

    2016-04-01

    controlled to great precision, but in a Cubesat , there may be no attitude determination at all. Such a Cubesat might treat sun angle and tumbling rates as...could be sensitive to small differences in motor controller timing. In these cases, the analyst might choose to model the entire deployment path, with...knowledge of the material damage model or motor controller timing precision. On the other hand, if many repeated and environmentally representative

  15. Mature clustered, regularly interspaced, short palindromic repeats RNA (crRNA) length is measured by a ruler mechanism anchored at the precursor processing site.

    Science.gov (United States)

    Hatoum-Aslan, Asma; Maniv, Inbal; Marraffini, Luciano A

    2011-12-27

    Precise RNA processing is fundamental to all small RNA-mediated interference pathways. In prokaryotes, clustered, regularly interspaced, short palindromic repeats (CRISPR) loci encode small CRISPR RNAs (crRNAs) that protect against invasive genetic elements by antisense targeting. CRISPR loci are transcribed as a long precursor that is cleaved within repeat sequences by CRISPR-associated (Cas) proteins. In many organisms, this primary processing generates crRNA intermediates that are subject to additional nucleolytic trimming to render mature crRNAs of specific lengths. The molecular mechanisms underlying this maturation event remain poorly understood. Here, we defined the genetic requirements for crRNA primary processing and maturation in Staphylococcus epidermidis. We show that changes in the position of the primary processing site result in extended or diminished maturation to generate mature crRNAs of constant length. These results indicate that crRNA maturation occurs by a ruler mechanism anchored at the primary processing site. We also show that maturation is mediated by specific cas genes distinct from those genes involved in primary processing, showing that this event is directed by CRISPR/Cas loci.

  16. Mold deformation in soft UV-nanoimprint lithography

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    UV-nanoimprint lithography (UV-NIL) using a soft mold is a promising technique with low cost and high throughput for producing the submicron scale large-area patterns. However, the deformations of the soft mold during imprinting process which can cause serious consequences have to be understood for the practical application of the process. This paper investigated the deformation of the soft mold by theoretical analyses, numerical simulations, and experimental studies. We simulated the mold deformation using a simplified model and finite element method. The simulation and the related experimental results agree well with each other. Through the investigation, the mechanism and affected factors of the mold deformation are revealed, and some useful conclusions have been achieved. These results will be valuable in optimizing the imprinting process conditions and mold design for improving the quality of transferred patterns.

  17. Thermal management of masks for deep x-ray lithography.

    Energy Technology Data Exchange (ETDEWEB)

    Khounsary, A.; Chojnowski, D.; Mancini, D.C.; Lai, B.; Dejus, R.

    1997-11-18

    This paper addresses some options and techniques in the thermal management of masks used in deep x-ray lithography. The x-ray masks are thin plates made of low-atomic-number materials on which a patterned thin film of a high-atomic-number metal has been deposited. When they are exposed to an x-ray beam, part of the radiation is transmitted to replicate the pattern on a downstream photoresist, and the remainder is absorbed in the mask in the form of heat. This heat load can cause deformation of the mask and thus image distortion in the lithography process. The mask geometry considered in the present study is 100 mm x 100 mm in area, and about 0.1 to 2 mm thick. The incident radiation is a bending magnet x-ray beam having a footprint of 60 mm x 4 mm at the mask. The mask is scanned vertically about {+-} 30 mm so that a 60 mm x 60 mm area is exposed. the maximum absorbed heat load in the mask is 80 W, which is significantly greater than a few watts encountered in previous systems. In this paper, cooling techniques, substrate material selection, transient and steady state thermal and structural behavior, and other thermo-mechanical aspects of mask design are discussed. It is shown that, while diamond and graphite remain attractive candidates, at present beryllium is a more suitable material for this purpose and, when properly cooled, can provide the necessary dimensional tolerance.

  18. Soft lithography for micro- and nanoscale patterning.

    Science.gov (United States)

    Qin, Dong; Xia, Younan; Whitesides, George M

    2010-03-01

    This protocol provides an introduction to soft lithography--a collection of techniques based on printing, molding and embossing with an elastomeric stamp. Soft lithography provides access to three-dimensional and curved structures, tolerates a wide variety of materials, generates well-defined and controllable surface chemistries, and is generally compatible with biological applications. It is also low in cost, experimentally convenient and has emerged as a technology useful for a number of applications that include cell biology, microfluidics, lab-on-a-chip, microelectromechanical systems and flexible electronics/photonics. As examples, here we focus on three of the commonly used soft lithographic techniques: (i) microcontact printing of alkanethiols and proteins on gold-coated and glass substrates; (ii) replica molding for fabrication of microfluidic devices in poly(dimethyl siloxane), and of nanostructures in polyurethane or epoxy; and (iii) solvent-assisted micromolding of nanostructures in poly(methyl methacrylate).

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

    Science.gov (United States)

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

    2017-09-12

    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 (PMMA), 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 (UV) 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. © 2017 IOP Publishing Ltd.

  20. Effect of variable number of tandem repeats polymorphism in the human dopamine transporter gene on conflict information processing according to event-related potential

    Institute of Scientific and Technical Information of China (English)

    Chunyu Han; Yuping Wang; Xin Wang; Ying Liu

    2010-01-01

    The dopamine transporter(DAT)is responsible for dopamine reuptake from the synaptic cleft.A variable number of tandem repeats polymorphism in the DAT gene is related to DAT availability and has been associated with cognition.With the advantage of high-time resolution,event-related potential is an important method to study the time course of human information processing.Previous results have suggested that dopamine exhibits a close relationship with conflicting information processing.Therefore,the present study assumed that conflicting information processing could be influenced by DAT variable number of tandem repeats polymorphism.To confirm this,the present study analyzed the influence of DAT genotypes on N270,which is presumed to reflect neural activity of conflict information processing in young healthy adults.A S1-S2 matching task was performed in healthy adults with 10/10 genotype(n = 14)and 10/9genotypes(n = 14),respectively,when event-related potentials were recorded.Results demonstrated that subjects with the 10/10 genotype exhibited shorter N270 latency and quicker reaction times compared with subjects with the 10/9 genotype.There were no differences in N270amplitude between the two genotypes.These results suggested that 10/10 genotype subjects more efficiently processed conflict information.

  1. Resolution enhancement techniques in optical lithography

    CERN Document Server

    Wong, Alfred K

    2001-01-01

    Ever-smaller IC devices are pushing the optical lithography envelope, increasing the importance of resolution enhancement techniques. This tutorial encompasses two decades of research. It discusses theoretical and practical aspects of commonly used techniques, including optical imaging and resolution, modified illumination, optical proximity correction, alternating and attenuating phase-shifting masks, selecting RETs, and second-generation RETs. Useful for students and practicing lithographers.

  2. Liquid-Phase Beam Pen Lithography.

    Science.gov (United States)

    He, Shu; Xie, Zhuang; Park, Daniel J; Liao, Xing; Brown, Keith A; Chen, Peng-Cheng; Zhou, Yu; Schatz, George C; Mirkin, Chad A

    2016-02-24

    Beam pen lithography (BPL) in the liquid phase is evaluated. The effect of tip-substrate gap and aperture size on patterning performance is systematically investigated. As a proof-of-concept experiment, nanoarrays of nucleotides are synthesized using BPL in an organic medium, pointing toward the potential of using liquid phase BPL to perform localized photochemical reactions that require a liquid medium. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Formation of Magnetic Anisotropy by Lithography.

    Science.gov (United States)

    Kim, Si Nyeon; Nam, Yoon Jae; Kim, Yang Doo; Choi, Jun Woo; Lee, Heon; Lim, Sang Ho

    2016-05-24

    Artificial interface anisotropy is demonstrated in alternating Co/Pt and Co/Pd stripe patterns, providing a means of forming magnetic anisotropy using lithography. In-plane hysteresis loops measured along two principal directions are explained in depth by two competing shape and interface anisotropies, thus confirming the formation of interface anisotropy at the Co/Pt and Co/Pd interfaces of the stripe patterns. The measured interface anisotropy energies, which are in the range of 0.2-0.3 erg/cm(2) for both stripes, are smaller than those observed in conventional multilayers, indicating a decrease in smoothness of the interfaces when formed by lithography. The demonstration of interface anisotropy in the Co/Pt and Co/Pd stripe patterns is of significant practical importance, because this setup makes it possible to form anisotropy using lithography and to modulate its strength by controlling the pattern width. Furthermore, this makes it possible to form more complex interface anisotropy by fabricating two-dimensional patterns. These artificial anisotropies are expected to open up new device applications such as multilevel bits using in-plane magnetoresistive thin-film structures.

  4. Electron Beam Lithography for nano-patterning

    DEFF Research Database (Denmark)

    Greibe, Tine; Anhøj, Thomas Aarøe; Khomtchenko, Elena;

    2014-01-01

    Electron beam lithography is a versatile tool for fabrication of nano-sized patterns. The patterns are generated by scanning a focused beam of high-energy electrons onto a substrate coated with a thin layer of electron-sensitive polymer (resist), i.e. by directly writing custom-made patterns...... in a polymer. Electron beam lithography is a suitable method for nano-sized production, research, or development of semiconductor components on a low-volume level. Here, we present electron beam lithography available at DTU Danchip. We expertize a JEOL 9500FZ with electrons accelerated to an energy of 100ke......V and focused to a beam spot size down to ~5nm. The electron beam can scan across the substrate with a speed of 100MHz and can write areas of 1mm x 1mm without stitching. In order to ensure high-precision patterning, the beam position on the substrate is controlled by a two-stage deflector system and substrates...

  5. Metallic resist for phase-change lithography

    Science.gov (United States)

    Zeng, Bi Jian; Huang, Jun Zhu; Ni, Ri Wen; Yu, Nian Nian; Wei, Wei; Hu, Yang Zhi; Li, Zhen; Miao, Xiang Shui

    2014-06-01

    Currently, the most widely used photoresists in optical lithography are organic-based resists. The major limitations of such resists include the photon accumulation severely affects the quality of photolithography patterns and the size of the pattern is constrained by the diffraction limit. Phase-change lithography, which uses semiconductor-based resists such as chalcogenide Ge2Sb2Te5 films, was developed to overcome these limitations. Here, instead of chalcogenide, we propose a metallic resist composed of Mg58Cu29Y13 alloy films, which exhibits a considerable difference in etching rate between amorphous and crystalline states. Furthermore, the heat distribution in Mg58Cu29Y13 thin film is better and can be more easily controlled than that in Ge2Sb2Te5 during exposure. We succeeded in fabricating both continuous and discrete patterns on Mg58Cu29Y13 thin films via laser irradiation and wet etching. Our results demonstrate that a metallic resist of Mg58Cu29Y13 is suitable for phase change lithography, and this type of resist has potential due to its outstanding characteristics.

  6. Stereomask lithography for multi-protein patterning.

    Science.gov (United States)

    Zhao, Siwei; Chen, Arnold; Revzin, Alexander; Pan, Tingrui

    2014-01-01

    The advances of biologically-friendly micropatterning technologies have benefited many areas of biological and medical research, including quantitative biochemical assay, point-of-care devices, biosensing and regenerative medicine. Conventional micropatterning techniques, for example, photolithography and soft lithography, have seen encouraging adaptation to creating biological micropatterns in the last decades. However, they still have not completely addressed the major needs of constructing multi-object biological microarrays with single-cell resolution without requiring cleanroom access. In this chapter, we present a novel versatile biological lithography technique to achieve integrated multi-object patterning with high feature resolution and high adaptability to various biomaterials, referred to as stereomask lithography (SML). A novel three-dimensional stereomask has been developed for successive patterning of multiple objects. The stereomask consists of both patterned through holes, which layout new micropatterns and non-through recesses, which protect pre-existing features on the substrate. Furthermore, high-precision reversible alignment among multiple bio-objects is achieved by adopting a peg-in-hole design between the substrate and stereomasks. As demonstration, we have successfully used the SML technique to construct complex biological microenvironment with various bio-functional components at single-cell resolution. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Metallic resist for phase-change lithography

    Science.gov (United States)

    Zeng, Bi Jian; Huang, Jun Zhu; Ni, Ri Wen; Yu, Nian Nian; Wei, Wei; Hu, Yang Zhi; Li, Zhen; Miao, Xiang Shui

    2014-01-01

    Currently, the most widely used photoresists in optical lithography are organic-based resists. The major limitations of such resists include the photon accumulation severely affects the quality of photolithography patterns and the size of the pattern is constrained by the diffraction limit. Phase-change lithography, which uses semiconductor-based resists such as chalcogenide Ge2Sb2Te5 films, was developed to overcome these limitations. Here, instead of chalcogenide, we propose a metallic resist composed of Mg58Cu29Y13 alloy films, which exhibits a considerable difference in etching rate between amorphous and crystalline states. Furthermore, the heat distribution in Mg58Cu29Y13 thin film is better and can be more easily controlled than that in Ge2Sb2Te5 during exposure. We succeeded in fabricating both continuous and discrete patterns on Mg58Cu29Y13 thin films via laser irradiation and wet etching. Our results demonstrate that a metallic resist of Mg58Cu29Y13 is suitable for phase change lithography, and this type of resist has potential due to its outstanding characteristics. PMID:24931505

  8. Design and simulation of large field plate lithography lens

    Science.gov (United States)

    Deng, Chao; Xing, Tingwen; Lin, Wumei; Zhu, Xianchang

    2016-10-01

    Because industry demand for LED,LCD panel continues to increase, the high yield of micron-scale resolution lithography is increasingly prominent for manufacturers, which requires the field of lithography objective lens becomes larger. This paper designed a lithography lens with large field, whose effective image side field will reach to 132 × 132mm.Subsequently, the tolerance was analysed by simulation for the optical system. Finally, it is proved that the design meets the requirements of micron-scale resolution.

  9. Synchrotron Radiation Lithography and MEMS Technique at NSRL

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Two beamlines and stations for soft X-ray lithography and hard X-ray lithography at NSRL are presented. Synchrotron radiation lithography (SRL) and mask techniques are developed, and the micro-electro-mechanical systems (MEMS) techniques are also investigated at NSRL. In this paper, some results based on SRL and MEMS techniques are reported, and sub-micron and high aspect ratio microstructures are given. Some micro-devices, such as microreactors are fabricated at NSRL.

  10. 75 FR 44015 - Certain Semiconductor Products Made by Advanced Lithography Techniques and Products Containing...

    Science.gov (United States)

    2010-07-27

    ... COMMISSION Certain Semiconductor Products Made by Advanced Lithography Techniques and Products Containing... importation of certain semiconductor products made by advanced lithography techniques and products containing... certain semiconductor products made by advanced lithography techniques or products containing same...

  11. Submicron three-dimensional structures fabricated by reverse contact UV nanoimprint lithography

    DEFF Research Database (Denmark)

    Kehagias, N.; Reboud, Vincent; Chansin, G.

    2006-01-01

    The fabrication of a three-dimensional multilayered nanostructure is demonstrated with a newly developed nanofabrication technique, namely, reverse contact ultraviolet nanoimprint lithography. This technique is a combination of reverse nanoimprint lithography and contact ultraviolet lithography...

  12. High-resolution imprint and soft lithography for patterning self-assembling systems

    NARCIS (Netherlands)

    Duan, X.

    2010-01-01

    This thesis contributes to the continuous development of patterning strategies in several different areas of unconventional nanofabrication. A series of soft lithography approaches (microcontact printing, nanomolding in capillaries), nanoimprint lithography (NIL), and capillary force lithography

  13. Expected innovations of optical lithography in the next 10 years

    Science.gov (United States)

    Owa, Soichi; Hirayanagi, Noriyuki

    2016-03-01

    In the past 10 years, immersion lithography has been the most effective high volume manufacturing method for the critical layers of semiconductor devices. Thinking of the next 10 years, we can expect continuous improvement on existing 300 mm wafer scanners with better accuracy and throughput to enhance the total output value per input cost. This value productivity, however, can be upgraded also by larger innovations which might happen in optical lithography. In this paper, we will discuss the possibilities and the impossibilities of potential innovation ideas of optical lithography, which are 450 mm wafer, optical maskless, multicolor lithography, and metamaterial.

  14. Modelling of L-valine Repeated Fed-batch Fermentation Process Taking into Account the Dissolved Oxygen Tension

    Directory of Open Access Journals (Sweden)

    Tzanko Georgiev

    2009-03-01

    Full Text Available This article deals with synthesis of dynamic unstructured model of variable volume fed-batch fermentation process with intensive droppings for L-valine production. The presented approach of the investigation includes the following main procedures: description of the process by generalized stoichiometric equations; preliminary data processing and calculation of specific rates for main kinetic variables; identification of the specific rates takes into account the dissolved oxygen tension; establishment and optimisation of dynamic model of the process; simulation researches. MATLAB is used as a research environment.

  15. A Study for the Characteristic Changes Under the Repeated Thermal Exposure in the Process of Repairing Aircraft Sandwich Structures

    Science.gov (United States)

    Kim, Yun Hae; Han, Joong Won; Kim, Don Won; Choi, Byung Keun; Murakami, R.

    Delamination can be observed in the sound areas during and/or after a couple times exposure to the elevated curing temperature due to the repeated repair condition. This study was conducted for checking the degree of degradation of properties of the cured parts and delamination between skin prepreg and honeycomb core. Specimens with glass honeycomb sandwich construction and glass/epoxy prepreg were prepared. The specimens were cured 1 to 5 times at 260°F in an autoclave and each additionally exposed 50, 100 and 150 hours in the 260°F oven. Each specimen was tested for tensile strength, compressive strength, flatwise tensile strength and interlaminar shear strength. To monitor the characteristics of the resin itself, the cured resin was tested using DMA and DSC. As a results, the decrease of Tg value were observed in the specific specimen which is exposed over 50 hrs at 260°F. This means the change or degradative of resin properties is also related to the decrease of flatwise tensile properties. Accordingly, minimal exposure on the curing temperature is recommended for parts in order to prevent the delation and maintain the better condition.

  16. Maintenance of phenotypic variation: repeatibility, heritability, and size-dependent processes in a wild brook trout population

    Science.gov (United States)

    Benjamin H. Letcher; Jason A Coombs; Keith H. Nislow

    2011-01-01

    Phenotypic variation in body size can result from within-cohort variation in birth dates, among-individual growth variation and size-selective processes. We explore the relative effects of these processes on the maintenance of wide observed body size variation in stream-dwelling brook trout (Salvelinus fontinalis). Based on the analyses of multiple...

  17. High-resolution laser lithography based on vortex laser and composite layer

    Science.gov (United States)

    Zhan, Shichao; Liang, Yiyong; Li, Xiongfeng

    2016-11-01

    Traditional laser lithography systems cannot write sub-wavelength patterns due to the diffraction limit. In this paper, a novel super-resolution laser direct writing method is proposed to break through the diffraction limit. Compared with conventional lithography systems, the photoresist layer in this method is overlaid by an extra photochromic layer which is a mixture of metanil yellow and aqueous PVA solution. Then a vortex beam with a hollow energy distribution is used to expose the photochromic layer and make an annular region of the photochromic layer opaque to the writing beam. Thus, a virtual aperture is formed in the photochromic layer which can confine the diameter of the writing beam and reduce the linewidth exposed in the photoresist layer. Lithography process of this new method was modeled and a corresponding simulation was made. In this simulation, the intensity ratio of the two beams, relative absorption coefficients and other parameters were changed to study their influence to linewidth in the photoresist. An experimental setup was designed to validate the simulation, where the wavelengths of the writing beam and the vortex beam are 405 nm and 532 nm, respectively. These two beams are strictly coaxial when they are incident to the photochromic layer. The experimental results agree quite well with the model simulation, showing that the linewidth could be reduced by increasing the intensity ratio of the vortex beam to the writing beam. They also indicate that the vortex beam could effectively reduce the lithography linewidth to 300nm or even smaller.

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

    Science.gov (United States)

    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.

  19. Fabrication of anisotropically arrayed nano-slots metasurfaces using reflective plasmonic lithography.

    Science.gov (United States)

    Luo, Jun; Zeng, Bo; Wang, Changtao; Gao, Ping; Liu, Kaipeng; Pu, Mingbo; Jin, Jinjin; Zhao, Zeyu; Li, Xiong; Yu, Honglin; Luo, Xiangang

    2015-11-28

    Nanofabrication technology with high-resolution, high-throughput and low-cost is essential for the development of nanoplasmonic and nanophotonic devices. At present, most metasurfaces are fabricated in a point by point writing manner with electron beam lithography or a focused ion beam, which imposes a serious cost barrier with respect to practical applications. Near field optical lithography, seemingly providing a high-resolution and low-cost way, however, suffers from the ultra shallow depth and poor fidelity of obtained photoresist patterns due to the exponential decay feature of evanescent waves. Here, we propose a method of surface plasmonic imaging lithography by introducing a reflective plasmonic lens to amplify and compensate evanescent waves, resulting in the production of nano resist patterns with high fidelity, contrast and enhanced depth beyond that usually obtained by near field optical lithography. As examples, a discrete and anisotropically arrayed nano-slots mask pattern with different orientations and a size of 40 nm × 120 nm could be imaged in photoresist and transferred successfully onto a metal layer through an etching process. Evidence for the pattern quality is given by virtue of the fabricated metasurface lens devices showing good focusing performance in experiments. It is believed that this method provides a parallel, low-cost, high-throughput and large-area nanofabrication route for fabricating nanostructures of holograms, vortex phase plates, bio-sensors and solar cells etc.

  20. High resolution defect inspection of step and flash imprint lithography for 32 nm half-pitch patterning

    Science.gov (United States)

    McMackin, I.; Perez, J.; Selinidis, K.; Maltabes, J.; Resnick, D.; Sreenivassan, S. V.

    2008-03-01

    Imprint lithography has been shown to be an effective method for the replication of nanometer-scale structures from an imprint mask (template) or mold. Step and Flash Imprint Lithography (S-FIL®) is unique in its ability to address both resolution and alignment. Recently overlay across a 200 mm wafer of less than 20nm, 3σ has been demonstrated. Current S-FIL resolution and alignment performance motivates the consideration of nano-imprint lithography as a Next Generation Lithography (NGL) solution for IC production. During the S-FIL process, a transferable image, an imprint, is produced by mechanically molding a liquid UV-curable resist on a wafer. Acceptance of imprint lithography for CMOS manufacturing will require demonstration that it can attain defect levels commensurate with the requirements of cost-effective device production. This report summarizes the result of defect inspections of wafers patterned using S-FIL. Wafer inspections were performed with KLA Tencor- 2132 (KT-2132) and KLA Tencor eS23 (KT-eS32) automated patterned wafer inspection tools. Imprint specific defectivity was shown to be <=3 cm -2 with some wafers having defectivity of less than 1 cm -2 and many fields having 0 imprint specific defects, as measured with the KT-2132. KT eS32 inspection of 32 nm half pitch features indicated that the random defectivity resulting from the imprint process was low.

  1. Translation of lithography variability into after-etch performance: monitoring of golden hotspot

    Science.gov (United States)

    Finders, Jo; Kiers, Ton; Le Gratiet, Bertrand; Lakcher, Amine

    2016-10-01

    In the early phases of technology development, designers and process engineers have to converge toward efficient design rules. Their calculations are based on process assumptions and result in a design rule based on known process variability capabilities while taking into account enough margin to be safe not only for yield but especially for reliability. Unfortunately, even if designs tend to be regular, efficient design densities are still requiring aggressive configurations from which it is difficult to estimate dimension variabilities. Indeed, for a process engineer it is rather straightforward to estimate or even measure simple one-dimensional features (arrays of Lines & Spaces at various CD and pitches), but it starts to be less obvious for complex multidimensional features. After a context description related to the process assumptions, we will outline the work flow which is under evaluation to enable robust metrology of 2 dimensional complex features. Enabling new metrology possibilities reveals that process hotspots are showing complex behavior from lithography to etch pattern transfer. In this work we studied the interaction of lithography variability and etching for a mature 28 nm CMOS process. To study this interaction we used a test feature that has been found very sensitive to lithography process variations. This so-called "golden" hotspot shows edge-to-edge geometries from 88nm to 150nm, thus comprising all the through pitch physics in the lithography pattern transfer [1, 2]. It consists of three trenches. From previous work it was known that through trench there is a systematic variation in best focus due to the Mask 3D effects. At a given chosen focus, there is a distinct difference in profiles for the three trenches that will lead to pattern displacement effects during the etch transfer.

  2. Ordered Silicon Microwire Arrays Grown from Substrates Patterned Using Imprint Lithography and Electrodeposition

    OpenAIRE

    Audesirk, Heather A.; Warren, Emily L.; Ku, Jessie; Lewis, Nathan S.

    2015-01-01

    Silicon microwires grown by the vapor–liquid–solid process have attracted a great deal of interest as potential light absorbers for solar energy conversion. However, the research-scale techniques that have been demonstrated to produce ordered arrays of micro and nanowires may not be optimal for use as high-throughput processes needed for large-scale manufacturing. Herein we demonstrate the use of microimprint lithography to fabricate patterned templates for the confinement of an electrodeposi...

  3. Lithography - Green and Getting Greener

    Science.gov (United States)

    Levinson, Harry J.

    2011-06-01

    Today, many energy-saving technologies and practices are enabled or made more effective through the use of nano-electronics. Such technologies include hybrid and all-electric cars, as well as controllers to increase the efficiency of photovoltaic panels. Telecommuting, which enables people to work without traveling from their homes, has been made possible by personal computers and the internet. Reducing the costs of nano-electronics will make possible increased opportunities for the use of products that reduce energy consumption. The most effective way to reduce costs is to improve efficiency. Increased efficiency also provides the benefit of reducing energy and material consumption in the manufacturing of nano-electronics. For example, reducing photochemical usage decreases costs but also reduces material consumption and the need for disposal. Reduction of scrap and rework are direct improvements in efficiency. Cycle time reduction enables greater responsiveness to demand, reducing the amount of material started in processing but never completed. Good process control reduces scrap and rework during manufacturing and results in circuits that have high performance, yet lower power consumption, when used. There are ready opportunities for making the most of the natural tendencies of businesses to innovate and improve efficiency. The semiconductor industry has historically adopted process improvements that have increased worker safety and reduced the consumption of hazardous materials. An early example was the transition from solvent to aqueous photoresist developers. Today, all types of development can be conducted in safer equipment that minimizes the release of hazardous chemicals to the air and water. Non-toxic solvents, such as ethyl lactate, have been widely adopted. There are many opportunities for further improvement. For example, over 90% of resist goes down the drain using conventional spin-coating process, so there is an opportunity for greatly improved

  4. Modular Polymer Biosensors by Solvent Immersion Imprint Lithography

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Jayven S.; Xantheas, Sotiris S.; Grate, Jay W.; Wietsma, Thomas W.; Gratton, Enrico; Vasdekis, Andreas

    2016-01-01

    We recently demonstrated Solvent Immersion Imprint Lithography (SIIL), a rapid benchtop microsystem prototyping technique, including polymer functionalization, imprinting and bonding. Here, we focus on the realization of planar polymer sensors using SIIL through simple solvent immersion without imprinting. We describe SIIL’s impregnation characteristics, including an inherent mechanism that not only achieves practical doping concentrations, but their unexpected 4-fold enhancement compared to the immersion solution. Subsequently, we developed and characterized optical sensors for detecting molecular O2. To this end, a high dynamic range is reported, including its control through the immersion duration, a manifestation of SIIL’s modularity. Overall, SIIL exhibits the potential of improving the operating characteristics of polymer sensors, while significantly accelerating their prototyping, as it requires a few seconds of processing and no need for substrates or dedicated instrumentation. These are critical for O2 sensing as probed by way of example here, as well as any polymer permeable reactant.

  5. Polystyrene negative resist for high-resolution electron beam lithography

    Directory of Open Access Journals (Sweden)

    Ma Siqi

    2011-01-01

    Full Text Available Abstract We studied the exposure behavior of low molecular weight polystyrene as a negative tone electron beam lithography (EBL resist, with the goal of finding the ultimate achievable resolution. It demonstrated fairly well-defined patterning of a 20-nm period line array and a 15-nm period dot array, which are the densest patterns ever achieved using organic EBL resists. Such dense patterns can be achieved both at 20 and 5 keV beam energies using different developers. In addition to its ultra-high resolution capability, polystyrene is a simple and low-cost resist with easy process control and practically unlimited shelf life. It is also considerably more resistant to dry etching than PMMA. With a low sensitivity, it would find applications where negative resist is desired and throughput is not a major concern.

  6. Solvent immersion nanoimprint lithography of fluorescent conjugated polymers

    Energy Technology Data Exchange (ETDEWEB)

    Whitworth, G. L.; Zhang, S.; Stevenson, J. R. Y.; Ebenhoch, B.; Samuel, I. D. W.; Turnbull, G. A. [Organic Semiconductor Centre, SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS (United Kingdom)

    2015-10-19

    Solvent immersion imprint lithography (SIIL) was used to directly nanostructure conjugated polymer films. The technique was used to create light-emitting diffractive optical elements and organic semiconductor lasers. Gratings with lateral features as small as 70 nm and depths of ∼25 nm were achieved in poly(9,9-dioctylfluorenyl-2,7-diyl). The angular emission from the patterned films was studied, comparing measurement to theoretical predictions. Organic distributed feedback lasers fabricated with SIIL exhibited thresholds for lasing of ∼40 kW/cm{sup 2}, similar to those made with established nanoimprint processes. The results show that SIIL is a quick, convenient and practical technique for nanopatterning of polymer photonic devices.

  7. Using low-contrast negative-tone PMMA at cryogenic temperatures for 3D electron beam lithography.

    Science.gov (United States)

    Schnauber, Peter; Schmidt, Ronny; Kaganskiy, Arsenty; Heuser, Tobias; Gschrey, Manuel; Rodt, Sven; Reitzenstein, Stephan

    2016-05-13

    We report on a 3D electron beam lithography (EBL) technique using polymethyl methacrylate (PMMA) in the negative-tone regime as a resist. First, we briefly demonstrate 3D EBL at room temperature. Then we concentrate on cryogenic temperatures where PMMA exhibits a low contrast, which allows for straightforward patterning of 3D nano- and microstructures. However, conventional EBL patterning at cryogenic temperatures is found to cause severe damage to the microstructures. Through an extensive study of lithography parameters, exposure techniques, and processing steps we deduce a hypothesis for the cryogenic PMMA's structural evolution under electron beam irradiation that explains the damage. In accordance with this hypothesis, a two step lithography technique involving a wide-area pre-exposure dose slightly smaller than the onset dose is applied. It enables us to demonstrate a >95% process yield for the low-temperature fabrication of 3D microstructures.

  8. Development of procedures for programmable proximity aperture lithography

    Energy Technology Data Exchange (ETDEWEB)

    Whitlow, H.J., E-mail: harry.whitlow@he-arc.ch [Institut des Microtechnologies Appliquées Arc, Haute Ecole Arc Ingénierie, Eplatures-Grise 17, CH-2300 La Chaux-de-Fonds (Switzerland); Department of Physics, University of Jyväskylä, P.O. Box 35 (YFL), FI-40014 Jyväskylä (Finland); Gorelick, S. [VTT Technical Research Centre of Finland, P.O. Box 1000, Tietotie 3, Espoo, FI-02044 VTT (Finland); Puttaraksa, N. [Department of Physics, University of Jyväskylä, P.O. Box 35 (YFL), FI-40014 Jyväskylä (Finland); Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Napari, M.; Hokkanen, M.J.; Norarat, R. [Department of Physics, University of Jyväskylä, P.O. Box 35 (YFL), FI-40014 Jyväskylä (Finland)

    2013-07-01

    Programmable proximity aperture lithography (PPAL) with MeV ions has been used in Jyväskylä and Chiang Mai universities for a number of years. Here we describe a number of innovations and procedures that have been incorporated into the LabView-based software. The basic operation involves the coordination of the beam blanker and five motor-actuated translators with high accuracy, close to the minimum step size with proper anti-collision algorithms. By using special approaches, such writing calibration patterns, linearisation of position and careful backlash correction the absolute accuracy of the aperture size and position, can be improved beyond the standard afforded by the repeatability of the translator end-point switches. Another area of consideration has been the fluence control procedures. These involve control of the uniformity of the beam where different approaches for fluence measurement such as simultaneous aperture current and the ion current passing through the aperture using a Faraday cup are used. Microfluidic patterns may contain many elements that make-up mixing sections, reaction chambers, separation columns and fluid reservoirs. To facilitate conception and planning we have implemented a .svg file interpreter, that allows the use of scalable vector graphics files produced by standard drawing software for generation of patterns made up of rectangular elements.

  9. Pilot scale repeated fed-batch fermentation processes of the wine yeast Dekkera bruxellensis for mass production of resveratrol from Polygonum cuspidatum.

    Science.gov (United States)

    Kuo, Hsiao-Ping; Wang, Reuben; Lin, Yi-Sheng; Lai, Jinn-Tsyy; Lo, Yi-Chen; Huang, Shyue-Tsong

    2017-11-01

    Resveratrol has long been used as an ingredient in functional foods. Currently, Polygonum cuspidatum extract is the greatest natural source for resveratrol because of high concentrations of glycosidic-linked resveratrol. Thus, developing a cost-effective procedure to hydrolyze glucoside could substantially enhance resveratrol production from P. cuspidatum. This study selected Dekkera bruxellensis from several microorganisms based on its bioconversion and enzyme-specific activities. We demonstrated that the cells could be reused at least nine times while maintaining an average of 180.67U/L β-glucosidase activity. The average resveratrol bioconversion efficiency within five rounds of repeated usage was 108.77±0.88%. This process worked effectively when the volume was increased to 1200L, a volume at which approximately 35mgL(-1)h(-1) resveratrol per round was produced. This repeated fed-batch bioconversion process for resveratrol production is comparable to enzyme or cell immobilization strategies in terms of reusing cycles, but without incurring additional costs for immobilization. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Architecture for next-generation massively parallel maskless lithography system (MPML2)

    Science.gov (United States)

    Su, Ming-Shing; Tsai, Kuen-Yu; Lu, Yi-Chang; Kuo, Yu-Hsuan; Pei, Ting-Hang; Yen, Jia-Yush

    2010-03-01

    Electron-beam lithography is promising for future manufacturing technology because it does not suffer from wavelength limits set by light sources. Since single electron-beam lithography systems have a common problem in throughput, a multi-electron-beam lithography (MEBL) system should be a feasible alternative using the concept of massive parallelism. In this paper, we evaluate the advantages and the disadvantages of different MEBL system architectures, and propose our novel Massively Parallel MaskLess Lithography System, MPML2. MPML2 system is targeting for cost-effective manufacturing at the 32nm node and beyond. The key structure of the proposed system is its beamlet array cells (BACs). Hundreds of BACs are uniformly arranged over the whole wafer area in the proposed system. Each BAC has a data processor and an array of beamlets, and each beamlet consists of an electron-beam source, a source controller, a set of electron lenses, a blanker, a deflector, and an electron detector. These essential parts of beamlets are integrated using MEMS technology, which increases the density of beamlets and reduces the system cost. The data processor in the BAC processes layout information coming off-chamber and dispatches them to the corresponding beamlet to control its ON/OFF status. High manufacturing cost of masks is saved in maskless lithography systems, however, immense mask data are needed to be handled and transmitted. Therefore, data compression technique is applied to reduce required transmission bandwidth. The compression algorithm is fast and efficient so that the real-time decoder can be implemented on-chip. Consequently, the proposed MPML2 can achieve 10 wafers per hour (WPH) throughput for 300mm-wafer systems.

  11. A system to optimize mix-and-match overlay in lithography

    Science.gov (United States)

    Wakamoto, Shinji; Ishii, Yuuki; Yasukawa, Koji; Maejima, Shinroku; Kato, Atsuhiko; Robinson, John C.; Choi, Dong-Sub

    2008-03-01

    Critical processing factors in the lithography process include overlaying the pattern properly to previous layers and properly exposing the pattern to achieve the desired line width. Proper overlay can only be attained in the lithography process while the desired line width accuracy is achieved by both lithography and etch processes. Since CD is substantially influenced by etch processing, therefore, it is possible to say that overlay is one of the most important processing elements in the lithography process. To achieve the desired overlay accuracy, it is desirable to expose critical layers with the same exposure tool that exposed the previous or target layer. This need to dedicate a particular exposure tool, however, complicates the lot dispatching schedule and, even worse, decreases exposure tool utilization. In order to allow any exposure tool available to print the arriving lot, M&M (Mix and Match) overlay control becomes necessary. By reducing overlay errors in M&M control, lot dispatching scheduling will become more flexible and exposure tool utilization will improve. Since each exposure tool has a unique registration signature, high order errors appear when overlaying multiple layers exposed with different tools. Even with the same exposure tool, if a different illumination is used, a similar error will be seen. A correction scheme to make the signature differences has to be implemented, however manually characterizing each tool's signature per illumination condition is extremely tedious, and is subject human errors. The challenge is to design a system to perform the corrections automatically. In the previous paper(1), we have outlined concepts of the system scheme. The system has subsequently been developed and tested using exposure tools. In this paper test results are shown using automated distortion correction. By analyzing the results, suggestions for further improvements and further developments are shown.

  12. Manipulation of heat-diffusion channel in laser thermal lithography.

    Science.gov (United States)

    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.

  13. Roll-to-roll UV imprint lithography for flexible electronics

    NARCIS (Netherlands)

    Maury, P.; Turkenburg, D.H.; Stroeks, N.; Giesen, P.; Barbu, I.; Meinders, E.R.; Bremen, A. van; Iosad, N.; Werf, R. van der; Onvlee, H.

    2011-01-01

    We propose a roll-to-roll UV imprint lithography tool as a way to pattern flexible PET foil with µm-resolution. As a way to overcome dimensional instability of the foil and its effect on overlay, a self-align approach was investigated, that permits to make several layers in a single lithography step

  14. Thermoplastic microcantilevers fabricated by nanoimprint lithography

    DEFF Research Database (Denmark)

    Greve, Anders; Keller, Stephan Urs; Vig, Asger Laurberg;

    2010-01-01

    Nanoimprint lithography has been exploited to fabricate micrometre-sized cantilevers in thermoplastic. This technique allows for very well defined microcantilevers and gives the possibility of embedding structures into the cantilever surface. The microcantilevers are fabricated in TOPAS and are up...... to 500 μm long, 100 μm wide, and 4.5 μm thick. Some of the cantilevers have built-in ripple surface structures with heights of 800 nm and pitches of 4 μm. The yield for the cantilever fabrication is 95% and the initial out-of-plane bending is below 10 μm. The stiffness of the cantilevers is measured...

  15. Wave and particle in molecular interference lithography.

    Science.gov (United States)

    Juffmann, Thomas; Truppe, Stefan; Geyer, Philipp; Major, András G; Deachapunya, Sarayut; Ulbricht, Hendrik; Arndt, Markus

    2009-12-31

    The wave-particle duality of massive objects is a cornerstone of quantum physics and a key property of many modern tools such as electron microscopy, neutron diffraction or atom interferometry. Here we report on the first experimental demonstration of quantum interference lithography with complex molecules. Molecular matter-wave interference patterns are deposited onto a reconstructed Si(111) 7x7 surface and imaged using scanning tunneling microscopy. Thereby both the particle and the quantum wave character of the molecules can be visualized in one and the same image. This new approach to nanolithography therefore also represents a sensitive new detection scheme for quantum interference experiments.

  16. Wave and Particle in Molecular Interference Lithography

    CERN Document Server

    Juffmann, Thomas; Geyer, Philipp; Major, Andras G; Deachapunya, Sarayut; Ulbricht, Hendrik; Arndt, Markus; 10.1103/PhysRevLett.103.263601

    2010-01-01

    The wave-particle duality of massive objects is a cornerstone of quantum physics and a key property of many modern tools such as electron microscopy, neutron diffraction or atom interferometry. Here we report on the first experimental demonstration of quantum interference lithography with complex molecules. Molecular matter-wave interference patterns are deposited onto a reconstructed Si(111) 7x7 surface and imaged using scanning tunneling microscopy. Thereby both the particle and the quantum wave character of the molecules can be visualized in one and the same image. This new approach to nanolithography therefore also represents a sensitive new detection scheme for quantum interference experiments.

  17. Atom Lithography with a Chromium Atomic Beam

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wen-Tao; LI Tong-Bao

    2006-01-01

    @@ Direct write atom lithography is a new technique in which resonant light is used to pattern an atomic beam and the nanostructures are formed when the atoms deposit on the substrate. We design an experiment setup to fabricate chromium nanolines by depositing an atomic beam of 52 Cr through an off-resonant laser standing wave with the wavelength of 425.55 nm onto a silicon substrate. The resulting nanolines exhibit a period of 215 ± 3 nm with height of 1 nm.

  18. EUV lithography: progress, challenges, and outlook

    Science.gov (United States)

    Wurm, S.

    2014-10-01

    Extreme Ultraviolet Lithography (EUVL) has been in the making for more than a quarter century. The first EUVL production tools have been delivered over the past year and chip manufacturers and suppliers are maturing the technology in pilot line mode to prepare for high volume manufacturing (HVM). While excellent progress has been made in many technical and business areas to prepare EUVL for HVM introduction, there are still critical technical and business challenges to be addressed before the industry will be able to use EUVL in HVM.

  19. A simple electron-beam lithography system

    DEFF Research Database (Denmark)

    Mølhave, Kristian; Madsen, Dorte Nørgaard; Bøggild, Peter

    2005-01-01

    A large number of applications of electron-beam lithography (EBL) systems in nanotechnology have been demonstrated in recent years. In this paper we present a simple and general-purpose EBL system constructed by insertion of an electrostatic deflector plate system at the electron-beam exit...... of the column of a scanning electron microscope (SEM). The system can easily be mounted on most standard SEM systems. The tested setup allows an area of up to about 50 x 50 pm to be scanned, if the upper limit for acceptable reduction of the SEM resolution is set to 10 run. We demonstrate how the EBL system can...

  20. A multiple-locus variable-number tandem repeat analysis (MLVA) of Listeria monocytogenes isolated from Norwegian salmon-processing factories and from listeriosis patients.

    Science.gov (United States)

    Lunestad, B T; Truong, T T T; Lindstedt, B-A

    2013-10-01

    The objective of this study was to characterize Listeria monocytogenes isolated from farmed Atlantic salmon (Salmo salar) and the processing environment in three different Norwegian factories, and compare these to clinical isolates by multiple-locus variable-number tandem repeat analysis (MLVA). The 65 L. monocytogenes isolates obtained gave 15 distinct MLVA profiles. There was great heterogeneity in the distribution of MLVA profiles in factories and within each factory. Nine of the 15 MLVA profiles found in the fish-associated isolates were found to match human profiles. The MLVA profile 07-07-09-10-06 was the most common strain in Norwegian listeriosis patients. L. monocytogenes with this profile has previously been associated with at least two known listeriosis outbreaks in Norway, neither determined to be due to fish consumption. However, since this profile was also found in fish and in the processing environment, fish should be considered as a possible food vehicle during sporadic cases and outbreaks of listeriosis.

  1. Step and flash imprint lithography: A low-pressure, room-temperature nanoimprint lithography

    Science.gov (United States)

    Colburn, Matthew Earl

    Lithography process has been proven to be a high-resolution technique capable of patterning a wide variety of substrate at room temperature under low applied pressure in a fashion consistent with high volume manufacturing requirements.

  2. Development of new multilocus variable number of tandem repeat analysis (MLVA) for Listeria innocua and its application in a food processing plant.

    Science.gov (United States)

    Takahashi, Hajime; Ohshima, Chihiro; Nakagawa, Miku; Thanatsang, Krittaporn; Phraephaisarn, Chirapiphat; Chaturongkasumrit, Yuphakhun; Keeratipibul, Suwimon; Kuda, Takashi; Kimura, Bon

    2014-01-01

    Listeria innocua is an important hygiene indicator bacterium in food industries because it behaves similar to Listeria monocytogenes, which is pathogenic to humans. PFGE is often used to characterize bacterial strains and to track contamination source. However, because PFGE is an expensive, complicated, time-consuming protocol, and poses difficulty in data sharing, development of a new typing method is necessary. MLVA is a technique that identifies bacterial strains on the basis of the number of tandem repeats present in the genome varies depending on the strains. MLVA has gained attention due to its high reproducibility and ease of data sharing. In this study, we developed a MLVA protocol to assess L. innocua and evaluated it by tracking the contamination source of L. innocua in an actual food manufacturing factory by typing the bacterial strains isolated from the factory. Three VNTR regions of the L. innocua genome were chosen for use in the MLVA. The number of repeat units in each VNTR region was calculated based on the results of PCR product analysis using capillary electrophoresis (CE). The calculated number of repetitions was compared with the results of the gene sequence analysis to demonstrate the accuracy of the CE repeat number analysis. The developed technique was evaluated using 60 L. innocua strains isolated from a food factory. These 60 strains were classified into 11 patterns using MLVA. Many of the strains were classified into ST-6, revealing that this MLVA strain type can contaminate each manufacturing process in the factory. The MLVA protocol developed in this study for L. innocua allowed rapid and easy analysis through the use of CE. This technique was found to be very useful in hygiene control in factories because it allowed us to track contamination sources and provided information regarding whether the bacteria were present in the factories.

  3. Repeated head trauma is associated with smaller thalamic volumes and slower processing speed: the Professional Fighters' Brain Health Study.

    Science.gov (United States)

    Bernick, Charles; Banks, Sarah J; Shin, Wanyong; Obuchowski, Nancy; Butler, Sam; Noback, Michael; Phillips, Michael; Lowe, Mark; Jones, Stephen; Modic, Michael

    2015-08-01

    Cumulative head trauma may alter brain structure and function. We explored the relationship between exposure variables, cognition and MRI brain structural measures in a cohort of professional combatants. 224 fighters (131 mixed martial arts fighters and 93 boxers) participating in the Professional Fighters Brain Health Study, a longitudinal cohort study of licensed professional combatants, were recruited, as were 22 controls. Each participant underwent computerised cognitive testing and volumetric brain MRI. Fighting history including years of fighting and fights per year was obtained from self-report and published records. Statistical analyses of the baseline evaluations were applied cross-sectionally to determine the relationship between fight exposure variables and volumes of the hippocampus, amygdala, thalamus, caudate, putamen. Moreover, the relationship between exposure and brain volumes with cognitive function was assessed. Increasing exposure to repetitive head trauma measured by number of professional fights, years of fighting, or a Fight Exposure Score (FES) was associated with lower brain volumes, particularly the thalamus and caudate. In addition, speed of processing decreased with decreased thalamic volumes and with increasing fight exposure. Higher scores on a FES used to reflect exposure to repetitive head trauma were associated with greater likelihood of having cognitive impairment. Greater exposure to repetitive head trauma is associated with lower brain volumes and lower processing speed in active professional fighters. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  4. Hard Transparent Arrays for Polymer Pen Lithography.

    Science.gov (United States)

    Hedrick, James L; Brown, Keith A; Kluender, Edward J; Cabezas, Maria D; Chen, Peng-Cheng; Mirkin, Chad A

    2016-03-22

    Patterning nanoscale features across macroscopic areas is challenging due to the vast range of length scales that must be addressed. With polymer pen lithography, arrays of thousands of elastomeric pyramidal pens can be used to write features across centimeter-scales, but deformation of the soft pens limits resolution and minimum feature pitch, especially with polymeric inks. Here, we show that by coating polymer pen arrays with a ∼175 nm silica layer, the resulting hard transparent arrays exhibit a force-independent contact area that improves their patterning capability by reducing the minimum feature size (∼40 nm), minimum feature pitch (<200 nm for polymers), and pen to pen variation. With these new arrays, patterns with as many as 5.9 billion features in a 14.5 cm(2) area were written using a four hundred thousand pyramid pen array. Furthermore, a new method is demonstrated for patterning macroscopic feature size gradients that vary in feature diameter by a factor of 4. Ultimately, this form of polymer pen lithography allows for patterning with the resolution of dip-pen nanolithography across centimeter scales using simple and inexpensive pen arrays. The high resolution and density afforded by this technique position it as a broad-based discovery tool for the field of nanocombinatorics.

  5. Photochromic silver nanoparticles fabricated by nanosphere lithography

    Energy Technology Data Exchange (ETDEWEB)

    Meixner, Melanie; Sprafke, Alexander; Hallermann, Florian; Reismann, Maximilian; Wuttig, Matthias; Plessen, Gero von [Institute of Physics, RWTH Aachen University, 52056 Aachen (Germany)

    2009-07-01

    Photochromic materials change their color under irradiation with light. In previous work, we have studied the photochromic transformation of silver nanoparticles embedded in transition-metal oxides prepared by dc-sputter deposition, such as TiO{sub x}, ZrO{sub x} and HfO{sub x}. The silver nanoparticles are highly inhomogeneous in shape, size and spatial distribution. The photochromic effect is based on spectral hole burning in the inhomogeneously broadened particle-plasmon band. This hole burning is probably caused by photoemission of electrons from the resonantly excited particles. In the present work, we show that TiO{sub x}-embedded silver nanoparticles with improved photochromic properties can be fabricated through a combination of electron-beam evaporation and nanosphere lithography. Nanosphere lithography is a method to produce hexagonal arranged and equally shaped particles. The good reproducibility of this approach allows us to analyze the photochromic transformation in a more quantitative way than was possible with samples prepared by sputter deposition.

  6. Optical design for EUV lithography source collector

    Institute of Scientific and Technical Information of China (English)

    Shuqing Zhang; Qi Wang; Dongyuan Zhu; Runshun Li; Chang Liu

    2011-01-01

    @@ Wolter I collector is the best collector for extreme ultraviolet (EUV) lithography, which has a series of nested mirrors.It has high collection efficiency and can obtain more uniform intensity distribution at the intermediate focus (IF).A new design with the calculation sequence from the outer mirror to the inner one on the premise of satisfying the requirements of the collector is introduced.Based on this concept, a computer program is established and the optical parameters of the collector using the program is calculated.The design results indicate that the collector satisfies all the requirements.%Wolter I collector is the best collector for extreme ultraviolet (EUV) lithography, which has a series of nested mirrors. It has high collection efficiency and can obtain more uniform intensity distribution at the intermediate focus (IF). A new design with the calculation sequence from the outer mirror to the inner one on the premise of satisfying the requirements of the collector is introduced. Based on this concept, acomputer program is established and the optical parameters of the collector using the program is calculated.The design results indicate that the collector satisfies all the requirements.

  7. Isomaltulose production using free cells: optimisation of a culture medium containing agricultural wastes and conversion in repeated-batch processes.

    Science.gov (United States)

    Kawaguti, Haroldo Y; Buzzato, Michele F; Sato, Hélia H

    2007-04-01

    The enzyme glucosyltransferase is an industrially important enzyme since it produces non-cariogenic isomaltulose (6-O-alpha-D-glucopyronosyl-1-6-D-fructofuranose) from sucrose by intramolecular transglucosylation. The experimental designs and response surface methodology (RSM) were applied for the optimisation of the nutrient concentrations in the culture medium for the production of glucosyltransferase by Erwinia sp. D12 in shaken flasks at 200 rpm and 30 degrees C. A statistical analysis of the results showed that, in the range studied, the factors had a significant effect (P free Erwinia sp. D12 cells in a batch process using an orbital shaker. The influence of the parameters sucrose concentration, temperature, pH, and cell concentration on the conversion of sucrose into isomaltulose was studied. The free cells showed a high conversion rate of sucrose into isomaltulose using batch fermentation, obtaining an isomaltulose yield of 72.11% from sucrose solution 35% at 35 degrees C.

  8. Polymeric lithography editor: Editing lithographic errors with nanoporous polymeric probes.

    Science.gov (United States)

    Rajasekaran, Pradeep Ramiah; Zhou, Chuanhong; Dasari, Mallika; Voss, Kay-Obbe; Trautmann, Christina; Kohli, Punit

    2017-06-01

    A new lithographic editing system with an ability to erase and rectify errors in microscale with real-time optical feedback is demonstrated. The erasing probe is a conically shaped hydrogel (tip size, ca. 500 nm) template-synthesized from track-etched conical glass wafers. The "nanosponge" hydrogel probe "erases" patterns by hydrating and absorbing molecules into a porous hydrogel matrix via diffusion analogous to a wet sponge. The presence of an interfacial liquid water layer between the hydrogel tip and the substrate during erasing enables frictionless, uninterrupted translation of the eraser on the substrate. The erasing capacity of the hydrogel is extremely high because of the large free volume of the hydrogel matrix. The fast frictionless translocation and interfacial hydration resulted in an extremely high erasing rate (~785 μm(2)/s), which is two to three orders of magnitude higher in comparison with the atomic force microscopy-based erasing (~0.1 μm(2)/s) experiments. The high precision and accuracy of the polymeric lithography editor (PLE) system stemmed from coupling piezoelectric actuators to an inverted optical microscope. Subsequently after erasing the patterns using agarose erasers, a polydimethylsiloxane probe fabricated from the same conical track-etched template was used to precisely redeposit molecules of interest at the erased spots. PLE also provides a continuous optical feedback throughout the entire molecular editing process-writing, erasing, and rewriting. To demonstrate its potential in device fabrication, we used PLE to electrochemically erase metallic copper thin film, forming an interdigitated array of microelectrodes for the fabrication of a functional microphotodetector device. High-throughput dot and line erasing, writing with the conical "wet nanosponge," and continuous optical feedback make PLE complementary to the existing catalog of nanolithographic/microlithographic and three-dimensional printing techniques. This new PLE

  9. Lithography-induced limits to scaling of design quality

    Science.gov (United States)

    Kahng, Andrew B.

    2014-03-01

    Quality and value of an IC product are functions of power, performance, area, cost and reliability. The forthcoming 2013 ITRS roadmap observes that while manufacturers continue to enable potential Moore's Law scaling of layout densities, the "realizable" scaling in competitive products has for some years been significantly less. In this paper, we consider aspects of the question, "To what extent should this scaling gap be blamed on lithography?" Non-ideal scaling of layout densities has been attributed to (i) layout restrictions associated with multi-patterning technologies (SADP, LELE, LELELE), as well as (ii) various ground rule and layout style choices that stem from misalignment, reliability, variability, device architecture, and electrical performance vs. power constraints. Certain impacts seem obvious, e.g., loss of 2D flexibility and new line-end placement constraints with SADP, or algorithmically intractable layout stitching and mask coloring formulations with LELELE. However, these impacts may well be outweighed by weaknesses in design methodology and tooling. Arguably, the industry has entered a new era in which many new factors - (i) standard-cell library architecture, and layout guardbanding for automated place-and-route: (ii) performance model guardbanding and signoff analyses: (iii) physical design and manufacturing handoff algorithms spanning detailed placement and routing, stitching and RET; and (iv) reliability guardbanding - all contribute, hand in hand with lithography, to a newly-identified "design capability gap". How specific aspects of process and design enablements limit the scaling of design quality is a fundamental question whose answer must guide future RandD investment at the design-manufacturing interface. terface.

  10. Deep-etch x-ray lithography at the ALS: First results

    Energy Technology Data Exchange (ETDEWEB)

    Malek, C.K.; Jackson, K.H. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States); Brennen, R.A. [Jet Propulsion Lab., Pasadena, CA (United States)] [and others

    1997-04-01

    The fabrication of high-aspect-ratio and three-dimensional (3D) microstructures is of increasing interest in a multitude of applications in fields such as micromechanics, optics, and interconnect technology. Techniques and processes that enable lithography in thick materials differ from the planar technologies used in standard integrated circuit processing. Deep x-ray lithography permits extremely precise and deep proximity printing of a given pattern from a mask into a very thick resist. It requires a source of hard, intense, and well collimated x-ray radiation, as is provided by a synchrotron radiation source. The thick resist microstructures, so produced can be used as templates from which ultrahigh precision parts with high aspect ratios can be mass-produced out of a large variety of materials (metals, plastics, ceramics). This whole series of techniques and processes has been historically referred to as {open_quotes}LIGA,{close_quotes} from the German acronym for lithography, electroforming (Galvanoformung), and plastic molding (Abformung), the first development of the basic LIGA process having been performed at the Nuclear Research Center at Karlsruhe in Germany.

  11. High resolution hole patterning with EB lithography for NIL template production

    Science.gov (United States)

    Tanabe, Mana; Yagawa, Keisuke; Motokawa, Takeharu; Hagihara, Kazuki; Suenaga, Machiko; Saito, Masato; Kanamitsu, Shingo; Itoh, Masamitsu

    2016-05-01

    Nano imprint lithography (NIL) is one to one lithography and contact transfer technique using template. Therefore, the lithography performance depends greatly on the quality of the template pattern. In this study, we investigated the resolution and the defect level for hole patterning using chemical amplified resists (CAR) and VSB type EB writer, EBM9000. To form smaller pattern with high quality, high resolution resist process and high sensitivity etching process are needed. After these elements were optimized, we succeeded to form 24 nm dense hole pattern on template. In general, it is difficult to suppress the defect density in a large area because of fogging effect and process loading and so forth. However, from the view point of defect quality, 26 nm hole pattern is achieved to form with practical level in a large area. Therefore, we indicate the capability of forming 26 nm hole master template which will be required in 2019 from ITRS2013. These results show that this process is possible to obtain less than 30 nm hole pattern without enormous writing time. As future work, we will imprint master to replica template and check the printability.

  12. Design strategies for future lithography technologies (or: OPC will never die)

    Science.gov (United States)

    Schellenberg, Franklin M.

    2003-06-01

    Resolution Enhancement Technologies (RETs) have extended the life of optical lithography well into the regimes of k1=0.3. Although there are a number of RTEs widely in use now, all involve some degree of optical and process correction (OPC). This puts additional strain on the data handling and management capabilities for process calibration and mask preparation. Alternative lithogrpahic technologies, such as Extreme UV (EUV), electron projection lithography (EPL), direct-write maskless lithography (MLL), and even nanoimprint techniques have been proposed and are under rapid development. All these alternatives create patterns usinga wavelength (or the dimension of the writing tool itself) smaller than the desired feature. Since these should confortably increase k1 back to the values enjoyed many years ago, it is generally assumed that the issues associated with OPC and the data management for RETs will go away. This is not true. Although these will no longer have "optical proximity" effects to compensate, each of these processes introduces its own signature of distortions, which in turn will require compensation and the associated data management. In this paper, we will inventory the state of development for each of these technologies, and outline the expected compensations and requirements palced on data management that are associated with the adoption of the technology. These effects include electron proximity effects and pattern stitching for EPL, Flare induced proximity effects for EUV, gray scale mapping for various maskless techniques, and even local process biasing for various nanoimprint approaches.

  13. Approach of UV nanoimprint lithography using template with gas-permeable and gaseous adsorption for reduction of air-trapping issue

    Science.gov (United States)

    Takei, Satoshi; Sugino, Naoto; Kameda, Takao; Nakajima, Shinya; Hanabata, Makoto

    2016-10-01

    In this paper, we studied a novel approach, UV nanoimprint lithography using glucose-based template with gaspermeable and gaseous adsorption for reduction of air-trapping issue. The air-trapping issue in UV nanoimprint lithography resist is a cause of pattern failure in resist or UV curable materials. The results of 180 nm dense line patterning of UV curable patterning materials containing acetone in UV nanoimprint lithography using glucose-based template with gas-permeable and gaseous adsorption were effected to reduce the pattern failure as compared with that of the poly(dimethylsiloxane) without gas-permeable and gaseous adsorption as the reference. The proposed UV nanoimprint lithography using glucose-based template with gas-permeable and gaseous adsorption is one of the most promising processes ready to be investigated for mass-production of photomask applications.

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

    Science.gov (United States)

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

    2015-11-03

    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.

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

    Science.gov (United States)

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

    2015-11-01

    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.

  16. Direct Release of Sombrero-Shaped Magnetite Nanoparticles via Nanoimprint Lithography

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Byung Seok [Department of Materials Science and Engineering, University of Washington, Seattle WA 98195 USA; Zhang, Wei [Argonne National Laboratory, Lemont IL 60439 USA; Li, Zheng [Department of Materials Science and Engineering, University of Washington, Seattle WA 98195 USA; Krishnan, Kannan M. [Department of Materials Science and Engineering, University of Washington, Seattle WA 98195 USA

    2015-01-10

    Magnetic nanoparticles produced via nanoimprint lithography can change the current paradigm of fabrication processes from chemical “bottom-up” synthesis to “top-down” fabrication. The combination of controlled nondirectional magnetron sputtering, ETFE mold, bilayer lift-off, and dry etching release can control the shape, size, and structure of the fabricated nanoparticles. The resulting magnetic nanoparticles have a novel “sombrero” shape with complex and unique physical/magnetic properties.

  17. Optofluidic in situ maskless lithography of charge selective nanoporous hydrogel for DNA preconcentration

    OpenAIRE

    2010-01-01

    An optofluidic maskless photopolymerization process was developed for in situ negatively charged nanoporous hydrogel [poly-AMPS (2-acrylamido-2-methyl-1-propanesulfonic acid)] fabrication. The optofluidic maskless lithography system, which combines a high power UV source and digital mirror device, enables fast polymerization of arbitrary shaped hydrogels in a microfluidic device. The poly-AMPS hydrogel structures were positioned near the intersections of two microchannels, and were used as a ...

  18. Innovative SU-8 Lithography Techniques and Their Applications

    Directory of Open Access Journals (Sweden)

    Jeong Bong Lee

    2014-12-01

    Full Text Available SU-8 has been widely used in a variety of applications for creating structures in micro-scale as well as sub-micron scales for more than 15 years. One of the most common structures made of SU-8 is tall (up to millimeters high-aspect-ratio (up to 100:1 3D microstructure, which is far better than that made of any other photoresists. There has been a great deal of efforts in developing innovative unconventional lithography techniques to fully utilize the thick high aspect ratio nature of the SU-8 photoresist. Those unconventional lithography techniques include inclined ultraviolet (UV exposure, back-side UV exposure, drawing lithography, and moving-mask UV lithography. In addition, since SU-8 is a negative-tone photoresist, it has been a popular choice of material for multiple-photon interference lithography for the periodic structure in scales down to deep sub-microns such as photonic crystals. These innovative lithography techniques for SU-8 have led to a lot of unprecedented capabilities for creating unique micro- and nano-structures. This paper reviews such innovative lithography techniques developed in the past 15 years or so.

  19. Amine control for DUV lithography: identifying hidden sources

    Science.gov (United States)

    Kishkovich, Oleg P.; Larson, Carl E.

    2000-06-01

    The impact of airborne basic molecular contamination (MB) on the performance of chemically amplified (CA) resist systems has been a long standing problem. Low ppb levels of MB may be sufficient for robust 0.25 micrometer lithography with today's advanced CA resist systems combined with adequate chemical air filtration. However, with minimum CD targets heading below 150 nm, the introduction of new resist chemistries for Next Generation Lithography, and the trend towards thinner resists, the impact of MB at low and sub-ppb levels again becomes a critical manufacturing issue. Maximizing process control at aggressive feature sizes requires that the level of MB be maintained below a certain limit, which depends on such parameters as the sensitivity of the CA resist, the type of production tools, product mix, and process characteristics. Three approaches have been identified to reduce the susceptibility of CA resists to MB: effective chemical air filtration, modifications to resist chemistry/processing and cleanroom protocols involving MB monitoring and removal of MB sources from the fab. The final MB concentration depends on the effectiveness of filtration resources and on the total pollution originating from different sources in and out of the cleanroom. There are many well-documented sources of MB. Among these are: ambient air; polluted exhaust from other manufacturing areas re-entering the cleanroom through make-up air handlers; manufacturing process chemicals containing volatile molecular bases; certain cleanroom construction materials, such as paint and ceiling tiles; and volatile, humidifier system boiler additives (corrosion inhibitors), such as morpholine, cyclohexylamine, and dimethylaminoethanol. However, there is also an indeterminate number of other 'hidden' pollution sources, which are neither obvious nor well-documented. None of these sources are new, but they had little impact on earlier semiconductor manufacturing processes because the contamination

  20. Resolution considerations in MeV ion microscopy and lithography

    Energy Technology Data Exchange (ETDEWEB)

    Norarat, Rattanaporn, E-mail: rattanaporn@rmutl.ac.th [University of Applied Sciences (HES-SO), Haute Ecole Arc Ingénierie, Eplatures-Gris 17, CH-2300 La Chaux-de-Fonds (Switzerland); Faculty of Sciences and Agricultural Technology, Rajamangala University of Technology Lanna, Chiang Rai, 57120 Chiang Rai (Thailand); Whitlow, Harry J. [University of Applied Sciences (HES-SO), Haute Ecole Arc Ingénierie, Eplatures-Gris 17, CH-2300 La Chaux-de-Fonds (Switzerland)

    2015-04-01

    There a disparity between the way the resolution is specified in microscopy and lithography using light compared to MeV ion microscopy and lithography. In this work we explore the implications of the way the resolution is defined with a view to answering the questions; how are the resolving powers in MeV ion microscopy and lithography relate to their optical counterparts? and how do different forms of point spread function affect the modulation transfer function and the sharpness of the edge profile?.

  1. Workshop on compact storage ring technology: applications to lithography

    Energy Technology Data Exchange (ETDEWEB)

    1986-05-30

    Project planning in the area of x-ray lithography is discussed. Three technologies that are emphasized are the light source, the lithographic technology, and masking technology. The needs of the semiconductor industry in the lithography area during the next decade are discussed, particularly as regards large scale production of high density dynamic random access memory devices. Storage ring parameters and an overall exposure tool for x-ray lithography are addressed. Competition in this area of technology from Germany and Japan is discussed briefly. The design of a storage ring is considered, including lattice design, magnets, and beam injection systems. (LEW)

  2. Photonic integrated circuits: new challenges for lithography

    Science.gov (United States)

    Bolten, Jens; Wahlbrink, Thorsten; Prinzen, Andreas; Porschatis, Caroline; Lerch, Holger; Giesecke, Anna Lena

    2016-10-01

    In this work routes towards the fabrication of photonic integrated circuits (PICs) and the challenges their fabrication poses on lithography, such as large differences in feature dimension of adjacent device features, non-Manhattan-type features, high aspect ratios and significant topographic steps as well as tight lithographic requirements with respect to critical dimension control, line edge roughness and other key figures of merit not only for very small but also for relatively large features, are highlighted. Several ways those challenges are faced in today's low-volume fabrication of PICs, including the concept multi project wafer runs and mix and match approaches, are presented and possible paths towards a real market uptake of PICs are discussed.

  3. Nanoscale plasmonic stamp lithography on silicon.

    Science.gov (United States)

    Liu, Fenglin; Luber, Erik J; Huck, Lawrence A; Olsen, Brian C; Buriak, Jillian M

    2015-02-24

    Nanoscale lithography on silicon is of interest for applications ranging from computer chip design to tissue interfacing. Block copolymer-based self-assembly, also called directed self-assembly (DSA) within the semiconductor industry, can produce a variety of complex nanopatterns on silicon, but these polymeric films typically require transformation into functional materials. Here we demonstrate how gold nanopatterns, produced via block copolymer self-assembly, can be incorporated into an optically transparent flexible PDMS stamp, termed a plasmonic stamp, and used to directly functionalize silicon surfaces on a sub-100 nm scale. We propose that the high intensity electric fields that result from the localized surface plasmons of the gold nanoparticles in the plasmonic stamps upon illumination with low intensity green light, lead to generation of electron-hole pairs in the silicon that drive spatially localized hydrosilylation. This approach demonstrates how localized surface plasmons can be used to enable functionalization of technologically relevant surfaces with nanoscale control.

  4. Current status of HESYRL lithography beam line

    Science.gov (United States)

    Qian, Shinan; Li, Guihe; Liu, Zewen; Chen, Qianhong; Jiang, Dikui; kan, Ya; Liu, Wanpo

    1990-06-01

    A lithography beam line, as the first of possibly six or more, has been installed in the Hefei Synchrotron Radiation Laboratory (HESYRL). A scanning mirror is used to cut off shorter wavelengths and to expand exposure dimensions vertically. The scanning mirror is oscillated by a stepping motor while an in-situ Moirè fringe grating system measures motor speed uniformity. Some testing results are given. In the first part of the beam line, there is a beryllium window to block longer wavelength light, a laser alignment unit to align the beam line and a special exposure shutter, which is controlled by another stepping motor. An exposure chamber with vacuum of 5 × 10-7 torr is located 7 meters downstream from the source point. Because there is no window at the entrance of the chamber, a differential pumping system is needed. The chamber is equipped with a mask-wafer system, driven by a third stepping motor.

  5. ATOMIC FORCE LITHOGRAPHY OF NANO MICROFLUIDIC CHANNELS FOR VERIFICATION AND MONITORING IN AQUEOUS SOLUTIONS

    Energy Technology Data Exchange (ETDEWEB)

    Torres, R.; Mendez-Torres, A.; Lam, P.

    2011-06-09

    The growing interest in the physics of fluidic flow in nanoscale channels, as well as the possibility for high sensitive detection of ions and single molecules is driving the development of nanofluidic channels. The enrichment of charged analytes due to electric field-controlled flow and surface charge/dipole interactions along the channel can lead to enhancement of sensitivity and limits-of-detection in sensor instruments. Nuclear material processing, waste remediation, and nuclear non-proliferation applications can greatly benefit from this capability. Atomic force microscopy (AFM) provides a low-cost alternative for the machining of disposable nanochannels. The small AFM tip diameter (< 10 nm) can provide for features at scales restricted in conventional optical and electron-beam lithography. This work presents preliminary results on the fabrication of nano/microfluidic channels on polymer films deposited on quartz substrates by AFM lithography.

  6. ATOMIC FORCE LITHOGRAPHY OF NANO/MICROFLUIDIC CHANNELS FOR VERIFICATION AND MONITORING OF AQUEOUS SOLUTIONS

    Energy Technology Data Exchange (ETDEWEB)

    Mendez-Torres, A.; Torres, R.; Lam, P.

    2011-07-15

    The growing interest in the physics of fluidic flow in nanoscale channels, as well as the possibility for high sensitive detection of ions and single molecules is driving the development of nanofluidic channels. The enrichment of charged analytes due to electric field-controlled flow and surface charge/dipole interactions along the channel can lead to enhancement of sensitivity and limits-of-detection in sensor instruments. Nuclear material processing, waste remediation, and nuclear non-proliferation applications can greatly benefit from this capability. Atomic force microscopy (AFM) provides a low-cost alternative for the machining of disposable nanochannels. The small AFM tip diameter (< 10 nm) can provide for features at scales restricted in conventional optical and electron-beam lithography. This work presents preliminary results on the fabrication of nano/microfluidic channels on polymer films deposited on quartz substrates by AFM lithography.

  7. Reaching the theoretical resonance quality factor limit in coaxial plasmonic nanoresonators fabricated by helium ion lithography.

    Science.gov (United States)

    Melli, M; Polyakov, A; Gargas, D; Huynh, C; Scipioni, L; Bao, W; Ogletree, D F; Schuck, P J; Cabrini, S; Weber-Bargioni, A

    2013-06-12

    Optical antenna structures have revolutionized the field of nano-optics by confining light to deep subwavelength dimensions for spectroscopy and sensing. In this work, we fabricated coaxial optical antennae with sub-10-nanometer critical dimensions using helium ion lithography (HIL). Wavelength dependent transmission measurements were used to determine the wavelength-dependent optical response. The quality factor of 11 achieved with our HIL fabricated structures matched the theoretically predicted quality factor for the idealized flawless gold resonators calculated by finite-difference time-domain (FDTD). For comparison, coaxial antennae with 30 nm critical dimensions were fabricated using both HIL and the more common Ga focus ion beam lithography (Ga-FIB). The quality factor of the Ga-FIB resonators was 60% of the ideal HIL results for the same design geometry due to limitations in the Ga-FIB fabrication process.

  8. Polymer microfluidic bioreactor fabrication by means of gray scale lithography technique

    Science.gov (United States)

    Sierakowski, Andrzej; Prokaryn, Piotr; Dobrowolski, Rafał; Malinowska, Anna; Szmigiel, Dariusz; Grabiec, Piotr; Trojanowski, Damian; Jakimowicz, Dagmara; Zakrzewska-Czerwinska, Jolanta

    2016-11-01

    In this paper we present a new method of polymer microfluidic bioreactor fabrication by means of a gray scale lithography technique. As a result of the gray scale lithography process the 3D model of the bioreactor is defined in photoresist. The obtained model serves as a sacrificial layer for the subsequent transfer of the 3D shape into the polymer material. The proposed method allows simultaneous definition of both the overall bioreactor geometry and the multi steps cell traps in a single photolithography step. Such microfluidic structure can be used for sorting cells based on their size. The developed solution significantly simplifies the production technology and reduces its costs in comparison to standard photolithography techniques.

  9. Recent Advances in Unconventional Lithography for Challenging 3D Hierarchical Structures and Their Applications

    Directory of Open Access Journals (Sweden)

    Jong Uk Kim

    2016-01-01

    Full Text Available In nanoscience and nanotechnology, nanofabrication is critical. Among the required processes for nanofabrication, lithography is one of core issues. Although conventional photolithography with recent remarkable improvement has contributed to the industry during the past few decades, fabrication of 3-dimensional (3D nanostructure is still challenging. In this review, we summarize recent advances for the construction of 3D nanostructures by unconventional lithography and the combination of two top-down approaches or top-down and bottom-up approaches. We believe that the 3D hierarchical nanostructures described here will have a broad range of applications having adaptable levels of functional integration of precisely controlled nanoarchitectures that are required by not only academia, but also industry.

  10. Fast fabrication of curved microlens array using DMD-based lithography

    Directory of Open Access Journals (Sweden)

    Zhimin Zhang

    2016-01-01

    Full Text Available Curved microlens array is the core element of the biologically inspired artificial compound eye. Many existing fabrication processes remain expensive and complicated, which limits a broad range of application of the artificial compound eye. In this paper, we report a fast fabrication method for curved microlens array by using DMD-based maskless lithography. When a three-dimensional (3D target curved profile is projected into a two-dimensional (2D mask, arbitrary curved microlens array can be flexibly and efficiently obtained by utilizing DMD-based lithography. In order to verify the feasibility of this method, a curved PDMS microlens array with 90 micro lenslets has been fabricated. The physical and optical characteristics of the fabricated microlens array suggest that this method is potentially suitable for applications in artificial compound eye.

  11. Light-sheet based lithography technique for patterning an array of microfluidic channels.

    Science.gov (United States)

    Mohan, Kavya; Mondal, Partha Pratim

    2017-02-08

    We propose a Light-sheet laser interference lithography technique for fabricating periodic microfluidic channels. This technique uses multiple light-sheet illumination pattern that is generated using a spatial filter at the back-aperture of the cylindrical lens. Specially designed spatial filter is used that give rise to a periodic pattern at the focal plane which is essentially a 1D Fourier transform of the spatial filter transfer function. One-dimensional focusing property of the cylindrical lens result in the generation of line shaped channel geometry. To design microfluidic channels, the illumination pattern is exposed to the glass substrate coated with a photopolymer sensitized to 532 nm and subsequently developed using standard chemical protocols. Experimentally, the 1D periodic channel structure has an approximate width and periodicity of approximately 11.25 microns. Light-sheets based lithography technique offer a fast and single-shot process to generate microfluidic channels. © 2016 Wiley Periodicals, Inc.

  12. Fabrication of Nanopillar Micropatterns by Hybrid Mask Lithography for Surface-Directed Liquid Flow

    Directory of Open Access Journals (Sweden)

    Fumihito Arai

    2013-06-01

    Full Text Available This paper presents a novel method for fabricating nanopillar micropatterns for surface-directed liquid flows. It employs hybrid mask lithography, which uses a mask consisting of a combination of a photoresist and nanoparticles in the photolithography process. The nanopillar density is controlled by varying the weight ratio of nanoparticles in the composite mask. Hybrid mask lithography was used to fabricate a surface-directed liquid flow. The effect of the surface-directed liquid flow, which was formed by the air-liquid interface due to nanopillar micropatterns, was evaluated, and the results show that the oscillation of microparticles, when the micro-tool was actuated, was dramatically reduced by using a surface-directed liquid flow. Moreover, the target particle was manipulated individually without non-oscillating ambient particles.

  13. Nano-imprint lithography using poly (methyl methacrylate) (PMMA) and polystyrene (PS) polymers

    Science.gov (United States)

    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.

  14. Silicon-Containing Spin-on Underlayer Material for Step and Flash Nanoimprint Lithography

    Science.gov (United States)

    Takei, Satoshi; Ogawa, Tsuyoshi; Deschner, Ryan; Jen, Kane; Nihira, Takayasu; Hanabata, Makoto; Willson, C. Grant

    2010-07-01

    Nanoimprint lithography is a newly developed patterning method that employs a hard template for the patterning of structures at micro- and nanometer scales. This technique has many advantages such as cost reduction, high resolution, low line edge roughness (LER), and easy operation. However, resist peeling, defects, low degree of planarization, and low throughput issues present challenges that must be resolved in order to mass produce advanced nanometer-scale devices. In this study, the new approach of using a silicon-containing spin-on hard mask underlayer material with high adhesion by reacting methacrylate groups of the underlayer to the acrylate groups of resist material during ultraviolet irradiation was demonstrated to obtain the excellent patterning dimensional accuracy and increase the process latitudes. The performance of this process is evaluated by using step and flash imprint lithography. The obtained high adhesion between the underlayer and resist material was found to lead a silicon-containing underlayer material to excellent patterning dimensional accuracy and 80 nm straight profiles. We expect that the silicon-containing a spin-on hard mask material under organic resist will be one of the most promising materials in the next generation of nanoimprint lithography.

  15. Surface phenomena related to mirror degradation in extreme ultraviolet (EUV) lithography

    Energy Technology Data Exchange (ETDEWEB)

    Madey, Theodore E. [Department of Physics and Astronomy, Laboratory for Surface Modification, Rutgers, State University of New Jersey, Piscataway, NJ 08854-8019 (United States)]. E-mail: madey@physics.rutgers.edu; Faradzhev, Nadir S. [Department of Physics and Astronomy, Laboratory for Surface Modification, Rutgers, State University of New Jersey, Piscataway, NJ 08854-8019 (United States); Yakshinskiy, Boris V. [Department of Physics and Astronomy, Laboratory for Surface Modification, Rutgers, State University of New Jersey, Piscataway, NJ 08854-8019 (United States); Edwards, N.V. [EUV Lithography Strategy Group, SEMATECH, 2706 Montopolis Dr., Austin, TX 78741-6499 (United States)

    2006-12-15

    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 {approx}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 H{sub 2}O 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.

  16. CDC Vital Signs: Preventing Repeat Teen Births

    Science.gov (United States)

    ... file Error processing SSI file Preventing Repeat Teen Births Recommend on Facebook Tweet Share Compartir On this ... Too many teens, ages 15–19, have repeat births. Nearly 1 in 5 births to teens, ages ...

  17. ANALYSIS OF LITHOGRAPHY BASED APPROACHES IN DEVELOPMENT OF SEMICONDUCTORS

    Directory of Open Access Journals (Sweden)

    Jatin Chopra

    2014-12-01

    Full Text Available The end of the 19th century brought about a change in the dynamics of computing by the development of the microprocessor. Huge bedroom size computers began being replaced by portable, smaller sized desktops. Today the world is dominated by silicon, which has circumscribed chip development for computers through microprocessors. Majority of the integrated circuits that are manufactured at present are developed using the concept of Lithography. This paper presents a detailed analysis of multiple Lithography methodologies as a means for advanced integrated circuit development. The study paper primarily restricts to examples in the context of Lithography, surveying the various existing techniques of Lithography in literature, examining feasible and efficient methods, highlighting the various pros and cons of each of them.

  18. Nanoscale 2.5-dimensional surface patterning with plasmonic lithography.

    Science.gov (United States)

    Jung, Howon; Park, Changhoon; Oh, Seonghyeon; Hahn, Jae W

    2017-08-29

    We report an extension of plasmonic lithography to nanoscale 2.5-dimensional (2.5D) surface patterning. To obtain the impulse response of a plasmonic lithography system, we described the field distribution of a point dipole source generated by a metallic ridge aperture with a theoretical model using the concepts of quasi-spherical waves and surface plasmon-polaritons. We performed deconvolution to construct an exposure map of a target shape for patterning. For practical applications, we fabricated several nanoscale and microscale structures, such as a cone, microlens array, nanoneedle, and a multiscale structure using the plasmonic lithography system. We verified the possibility of applying plasmonic lithography to multiscale structuring from a few tens of nanometres to a few micrometres in the lateral dimension. We obtained a root-mean-square error of 4.7 nm between the target shape and the patterned shape, and a surface roughness of 11.5 nm.

  19. Intel takes a stake in ultraviolet-lithography firm

    Science.gov (United States)

    Stafford, Ned

    2012-08-01

    The world's biggest computer-chip maker, Intel Corporation, has signed a major agreement with Dutch lithography firm ASML Holding to collaborate on developing the next generation of technology for manufacturing semiconductor chips.

  20. Image-Reversal Soft Lithography: Fabrication of Ultrasensitive Biomolecular Detectors.

    Science.gov (United States)

    Safaei, Tina Saberi; Das, Jagotamoy; Mahshid, Sahar Sadat; Aldridge, Peter M; Sargent, Edward H; Kelley, Shana O

    2016-04-20

    Image-reversal soft lithography enables the straightforward fabrication of high-performance biosensors without requiringhigh-resolution photolitography. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Fluid management in roll-to-roll nanoimprint lithography

    Science.gov (United States)

    Jain, A.; Bonnecaze, R. T.

    2013-06-01

    The key process parameters of UV roll-to-roll nanoimprint lithography are identified from an analysis of the fluid, curing, and peeling dynamics. The process includes merging of droplets of imprint material, curing of the imprint material from a viscous liquid to elastic solid resist, and pattern replication and detachment of the resist from template. The time and distances on the web or rigid substrate over which these processes occur are determined as function of the physical properties of the uncured liquid, the cured solid, and the roller configuration. The upper convected Maxwell equation is used to model the viscoelastic liquid and to calculate the force on the substrate and the torque on the roller. The available exposure time is found to be the rate limiting parameter and it is O(√Rho /uo), where R is the radius of the roller, ho is minimum gap between the roller and web, and uo is the velocity of the web. The residual layer thickness of the resist should be larger than the gap between the roller and the substrate to ensure complete feature filling and optimal pattern replication. For lower residual layer thickness, the droplets may not merge to form a continuous film for pattern transfer.

  2. Mask characterization for CDU budget breakdown in advanced EUV lithography

    Science.gov (United States)

    Nikolsky, Peter; Strolenberg, Chris; Nielsen, Rasmus; Nooitgedacht, Tjitte; Davydova, Natalia; Yang, Greg; Lee, Shawn; Park, Chang-Min; Kim, Insung; Yeo, Jeong-Ho

    2012-11-01

    As the ITRS Critical Dimension Uniformity (CDU) specification shrinks, semiconductor companies need to maintain a high yield of good wafers per day and a high performance (and hence market value) of finished products. This cannot be achieved without continuous analysis and improvement of on-product CDU as one of the main drivers for process control and optimization with better understanding of main contributors from the litho cluster: mask, process, metrology and scanner. In this paper we will demonstrate a study of mask CDU characterization and its impact on CDU Budget Breakdown (CDU BB) performed for an advanced EUV lithography with 1D and 2D feature cases. We will show that this CDU contributor is one of the main differentiators between well-known ArFi and new EUV CDU budgeting principles. We found that reticle contribution to intrafield CDU should be characterized in a specific way: mask absorber thickness fingerprints play a role comparable with reticle CDU in the total reticle part of the CDU budget. Wafer CD fingerprints, introduced by this contributor, may or may not compensate variations of mask CD's and hence influence on total mask impact on intrafield CDU at the wafer level. This will be shown on 1D and 2D feature examples in this paper. Also mask stack reflectivity variations should be taken into account: these fingerprints have visible impact on intrafield CDs at the wafer level and should be considered as another contributor to the reticle part of EUV CDU budget. We observed also MEEF-through-field fingerprints in the studied EUV cases. Variations of MEEF may also play a role for the total intrafield CDU and may be taken into account for EUV Lithography. We characterized MEEF-through-field for the reviewed features, the results to be discussed in our paper, but further analysis of this phenomenon is required. This comprehensive approach to characterization of the mask part of EUV CDU characterization delivers an accurate and integral CDU Budget

  3. Origin and fate of repeats in bacteria.

    Science.gov (United States)

    Achaz, G; Rocha, E P C; Netter, P; Coissac, E

    2002-07-01

    We investigated 53 complete bacterial chromosomes for intrachromosomal repeats. In previous studies on eukaryote chromosomes, we proposed a model for the dynamics of repeats based on the continuous genesis of tandem repeats, followed by an active process of high deletion rate, counteracted by rearrangement events that may prevent the repeats from being deleted. The present study of long repeats in the genomes of Bacteria and Archaea suggests that our model of interspersed repeats dynamics may apply to them. Thus the duplication process might be a consequence of very ancient mechanisms shared by all three domains. Moreover, we show that there is a strong negative correlation between nucleotide composition bias and the repeat density of genomes. We hypothesise that in highly biased genomes, non-duplicated small repeats arise more frequently by random effects and are used as primers for duplication mechanisms, leading to a higher density of large repeats.

  4. In-situ resist colloidal lithography for affordable plasmonics

    Science.gov (United States)

    Bochenkov, Vladimir E.

    2017-09-01

    A recently developed extension of Sparse Colloidal Lithography, an In-situ Resist Colloidal Lithography method is presented. The technique is based on in-situ deposition of structured resist layer having low adhesion to target material to form nanoparticles of desired shape. A high potential of the method is demonstrated by the examples of fabricated plasmonic nanostructures with different shapes, including concentric and non-concentric rings, disks and chiral comma-like particles.

  5. Maskless Electron-Beam Lithography for Trusted Microchip Production

    Science.gov (United States)

    2016-03-31

    no resolution improvement in optical lithography equipment. To enable manufacture of advanced designs, Intel was first to adopt unidirectional (1D...designed for high-volume manufacturing and unsuited for production of small quantities of a wide mix of special devices for DoD. The Defense...below: Reduce mask/equipment costs for production: In high volume manufacturing , lithography now accounts for more than 50% of wafer cost. In low

  6. Displacement Talbot lithography: an alternative technique to fabricate nanostructured metamaterials

    Science.gov (United States)

    Le Boulbar, E. D.; Chausse, P. J. P.; Lis, S.; Shields, P. A.

    2017-06-01

    Nanostructured materials are essential for many recent electronic, magnetic and optical devices. Lithography is the most common step used to fabricate organized and well calibrated nanostructures. However, feature sizes less than 200 nm usually require access to deep ultraviolet photolithography, e-beam lithography or soft lithography (nanoimprinting), which are either expensive, have low-throughput or are sensitive to defects. Low-cost, high-throughput and low-defect-density techniques are therefore of interest for the fabrication of nanostructures. In this study, we investigate the potential of displacement Talbot lithography for the fabrication of specific structures of interest within plasmonic and metamaterial research fields. We demonstrate that nanodash arrays and `fishnet'-like structures can be fabricated by using a double exposure of two different linear grating phase masks. Feature sizes can be tuned by varying the exposure doses. Such lithography has been used to fabricate metallic `fishnet'-like structures using a lift-off technique. This proof of principle paves the way to a low-cost, high-throughput, defect-free and large-scale technique for the fabrication of structures that could be useful for metamaterial and plasmonic metasurfaces. With the development of deep ultraviolet displacement Talbot lithography, the feature dimensions could be pushed lower and used for the fabrication of optical metamaterials in the visible range.

  7. Laser direct write system for fabricating seamless roll-to-roll lithography tools

    Science.gov (United States)

    Petrzelka, Joseph E.; Hardt, David E.

    2013-03-01

    Implementations of roll to roll contact lithography require new approaches towards manufacturing tooling, including stamps for roll to roll nanoimprint lithography (NIL) and soft lithography. Suitable roll based tools must have seamless micro- or nano-scale patterns and must be scalable to roll widths of one meter. The authors have developed a new centrifugal stamp casting process that can produce uniform cylindrical polymer stamps in a scalable manner. The pattern on the resulting polymer tool is replicated against a corresponding master pattern on the inner diameter of a centrifuge drum. This master pattern is created in photoresist using a UV laser direct write system. This paper discusses the design and implementation of a laser direct write system targeting the internal diameter of a rotating drum. The design uses flying optics to focus a laser beam along the axis of the centrifuge drum and to redirect the beam towards the drum surface. Experimental patterning results show uniform coatings of negative photoresist in the centrifuge drum that are effectively patterned with a 405 nm laser diode. Seamless patterns are shown to be replicated in a 50 mm diameter, 60 mm long cylindrical stamp made from polydimethylsiloxane (PDMS). Direct write results show gratings with line widths of 10 microns in negative photoresist. Using an FPGA, the laser can be accurately timed against the centrifuge encoder to create complex patterns.

  8. REBL: design progress toward 16 nm half-pitch maskless projection electron beam lithography

    Science.gov (United States)

    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.

  9. Effects of synchrotron radiation spectrum energy on polymethyl methacrylate photosensitivity to deep x-ray lithography

    CERN Document Server

    Mekaru, H; Hattori, T

    2003-01-01

    Since X-ray lithography requires a high photon flux to achieve deep resist exposure, a synchrotron radiation beam, which is not monochromatized, is generally used as a light source. If the synchrotron radiation beam is monochromatized, photon flux will decrease rapidly. Because of this reason, the wavelength dependence of the resist sensitivity has not been investigated for deep X-ray lithography. Measuring the spectrum of a white beam with a Si solid-state detector (SSD) is difficult because a white beam has a high intensity and an SSD has a high sensitivity. We were able to measure the spectrum and the photocurrent of a white beam from a beam line used for deep X-ray lithography by keeping the ring current below 0.05 mA. We evaluated the characteristics of the output beam based on the measured spectrum and photocurrent, and used them to investigate the relationship between the total exposure energy and the dose-processing depth with polymethyl methacrylate (PMMA). We found that it is possible to guess the p...

  10. Fully Scaled 0.5 Micron CMOS Technology Using Variable Shaped Electron Beam Lithography

    Science.gov (United States)

    Coane, Philip; Rudeck, Paul; Wang, Li-Kong; Wilson, Alan; Hohn, Fritz

    1988-06-01

    Over the past several years, CMOS technology has been continuously driven to achieve enhanced performance and higher density. The resulting reduction in semiconductor dimensions has surpasssed the limits attainable by the most advanced optical lithography tools. As a result, the utilization of electron beam lithography direct writing techniques to satisfy VLSI patterning requirements has increased significantly. In principle, variable shaped electron beam systems are capable of writing linewidths down to at least 0.1 micron. However, the successful application of sub-micron scaling principles to device fabrication involves an integration of tool capability and resist process control. In order to achieve the realization of improved CMOS device performance and circuit density, sub-micron ground rules (line width control and overlay) must be satisfied over the full chip. This paper reports on a high performance, fully scaled 0.5 micron CMOS technology developed for VLSI appli-cations. Significant gains in both density and performance at reduced power supply levels are realized over previously reported 1.0 micron technology. The details of the integrated lithography strategy used to achieve these results are presented.

  11. Low-Cost Fabrication of Hollow Microneedle Arrays Using CNC Machining and UV Lithography

    DEFF Research Database (Denmark)

    Lê Thanh, Hoà; Ta, B.Q.; Le The, H.

    2015-01-01

    In order to produce disposable microneedles for blood-collection devices in smart homecare monitoring systems, we have developed a simple low-cost scalable process for mass fabrication of sharp-tipped microneedle arrays. The key feature in this process is a design of computer numerical control......-machined aluminum sample (CAS). The inclined sidewalls on the CAS enable microfabricated traditional-shaped microneedles (TMNs) to be produced in the desired shape. This process provides significant advantages over other methods that use inclined lithography or anisotropic wet etching. TMNs with a length of 1510 mu...

  12. Thermochemical scanning probe lithography of protein gradients at the nanoscale

    Science.gov (United States)

    Albisetti, E.; Carroll, K. M.; Lu, X.; Curtis, J. E.; Petti, D.; Bertacco, R.; Riedo, E.

    2016-08-01

    Patterning nanoscale protein gradients is crucial for studying a variety of cellular processes in vitro. Despite the recent development in nano-fabrication technology, combining nanometric resolution and fine control of protein concentrations is still an open challenge. Here, we demonstrate the use of thermochemical scanning probe lithography (tc-SPL) for defining micro- and nano-sized patterns with precisely controlled protein concentration. First, tc-SPL is performed by scanning a heatable atomic force microscopy tip on a polymeric substrate, for locally exposing reactive amino groups on the surface, then the substrate is functionalized with streptavidin and laminin proteins. We show, by fluorescence microscopy on the patterned gradients, that it is possible to precisely tune the concentration of the immobilized proteins by varying the patterning parameters during tc-SPL. This paves the way to the use of tc-SPL for defining protein gradients at the nanoscale, to be used as chemical cues e.g. for studying and regulating cellular processes in vitro.

  13. Print-to-pattern dry film photoresist lithography

    Science.gov (United States)

    Garland, Shaun P.; Murphy, Terrence M., Jr.; Pan, Tingrui

    2014-05-01

    Here we present facile microfabrication processes, referred to as print-to-pattern dry film photoresist (DFP) lithography, that utilize the combined advantages of wax printing and DFP to produce micropatterned substrates with high resolution over a large surface area in a non-cleanroom setting. The print-to-pattern methods can be performed in an out-of-cleanroom environment making microfabrication much more accessible to minimally equipped laboratories. Two different approaches employing either wax photomasks or wax etchmasks from a solid ink desktop printer have been demonstrated that allow the DFP to be processed in a negative tone or positive tone fashion, respectively, with resolutions of 100 µm. The effect of wax melting on resolution and as a bonding material was also characterized. In addition, solid ink printers have the capacity to pattern large areas with high resolution, which was demonstrated by stacking DFP layers in a 50 mm × 50 mm woven pattern with 1 mm features. By using an office printer to generate the masking patterns, the mask designs can be easily altered in a graphic user interface to enable rapid prototyping.

  14. Print-to-Pattern Dry Film Photoresist Lithography.

    Science.gov (United States)

    Garland, Shaun P; Murphy, Terrence M; Pan, Tingrui

    2014-05-01

    Here we present facile microfabrication processes, referred to as Print-to-Pattern dry film photoresist (DFP) lithography, that utilize the combined advantages of wax printing and DFP to produce micropatterned substrates with high resolution over a large surface area in a non-cleanroom setting. The Print-to-Pattern methods can be performed in an out-of-cleanroom environment making microfabrication much more accessible to minimally equipped laboratories. Two different approaches employing either wax photomasks or wax etchmasks from a solid ink desktop printer have been demonstrated that allow the DFP to be processed in a negative tone or positive tone fashion, respectively, with resolutions of 100 μm. The effect of wax melting on resolution and as a bonding material was also characterized. In addition, solid ink printers have the capacity to pattern large areas with high resolution which was demonstrated by stacking DFP layers in a 50 mm × 50 mm woven pattern with 1 mm features. By using an office printer to generate the masking patterns, the mask designs can be easily altered in a graphic user interface to enable rapid prototyping.

  15. Silicon Quantum Dots for Quantum Information Processing

    Science.gov (United States)

    2013-11-01

    NeillConcelman CNOT Controlled-not gate CPU Central processing unit DC Direct current DCE dichloroethylene EBL Electron beam lithography ESR Electron spin...Electron Beam Lithography of Gates and Alignment Markers The main electron beam lithography ( EBL ) machine used for fabricating the devices in this thesis...vided additional support for patterning parameters such as drawing sequences, drawing directions and area dose, and controlling the EBL writing

  16. Nucleation process of magnitude 2 repeating earthquakes on the San Andreas Fault predicted by rate-and-state fault models with SAFOD drill core data

    Science.gov (United States)

    Kaneko, Yoshihiro; Carpenter, Brett M.; Nielsen, Stefan B.

    2017-01-01

    Recent laboratory shear-slip experiments conducted on a nominally flat frictional interface reported the intriguing details of a two-phase nucleation of stick-slip motion that precedes the dynamic rupture propagation. This behavior was subsequently reproduced by a physics-based model incorporating laboratory-derived rate-and-state friction laws. However, applying the laboratory and theoretical results to the nucleation of crustal earthquakes remains challenging due to poorly constrained physical and friction properties of fault zone rocks at seismogenic depths. Here we apply the same physics-based model to simulate the nucleation process of crustal earthquakes using unique data acquired during the San Andreas Fault Observatory at Depth (SAFOD) experiment and new and existing measurements of friction properties of SAFOD drill core samples. Using this well-constrained model, we predict what the nucleation phase will look like for magnitude ˜2 repeating earthquakes on segments of the San Andreas Fault at a 2.8 km depth. We find that despite up to 3 orders of magnitude difference in the physical and friction parameters and stress conditions, the behavior of the modeled nucleation is qualitatively similar to that of laboratory earthquakes, with the nucleation consisting of two distinct phases. Our results further suggest that precursory slow slip associated with the earthquake nucleation phase may be observable in the hours before the occurrence of the magnitude ˜2 earthquakes by strain measurements close (a few hundred meters) to the hypocenter, in a position reached by the existing borehole.

  17. Repeat-until-success quantum repeaters

    Science.gov (United States)

    Bruschi, David Edward; Barlow, Thomas M.; Razavi, Mohsen; Beige, Almut

    2014-09-01

    We propose a repeat-until-success protocol to improve the performance of probabilistic quantum repeaters. Conventionally, these rely on passive static linear-optics elements and photodetectors to perform Bell-state measurements (BSMs) with a maximum success rate of 50%. This is a strong impediment for entanglement swapping between distant quantum memories. Every time a BSM fails, entanglement needs to be redistributed between the corresponding memories in the repeater link. The key ingredients of our scheme are repeatable BSMs. Under ideal conditions, these turn probabilistic quantum repeaters into deterministic ones. Under realistic conditions, our protocol too might fail. However, using additional threshold detectors now allows us to improve the entanglement generation rate by almost orders of magnitude, at a nominal distance of 1000 km, compared to schemes that rely on conventional BSMs. This improvement is sufficient to make the performance of our scheme comparable to the expected performance of some deterministic quantum repeaters.

  18. Wafer and reticle positioning system for the Extreme Ultraviolet Lithography Engineering Test Stand

    Energy Technology Data Exchange (ETDEWEB)

    WRONOSKY,JOHN B.; SMITH,TONY G.; CRAIG,MARCUS J.; STURGIS,BEVERLY R.; DARNOLD,JOEL R.; WERLING,DAVID K.; KINCY,MARK A.; TICHENOR,DANIEL A.; WILLIAMS,MARK E.; BISCHOFF,PAUL

    2000-01-27

    This paper is an overview of the wafer and reticle positioning system of the Extreme Ultraviolet Lithography (EUVL) Engineering Test Stand (ETS). EUVL represents one of the most promising technologies for supporting the integrated circuit (IC) industry's lithography needs for critical features below 100nm. EUVL research and development includes development of capabilities for demonstrating key EUV technologies. The ETS is under development at the EUV Virtual National Laboratory, to demonstrate EUV full-field imaging and provide data that supports production-tool development. The stages and their associated metrology operated in a vacuum environment and must meet stringent outgassing specifications. A tight tolerance is placed on the stage tracking performance to minimize image distortion and provide high position repeatability. The wafer must track the reticle with less than {+-}3nm of position error and jitter must not exceed 10nm rms. To meet these performance requirements, magnetically levitated positioning stages utilizing a system of sophisticated control electronics will be used. System modeling and experimentation have contributed to the development of the positioning system and results indicate that desired ETS performance is achievable.

  19. Molecular self-assembly for biological investigations and nanoscale lithography

    Science.gov (United States)

    Cheunkar, Sarawut

    selective biorecognition. By carefully tuning the polar surface energy of polymeric stamps, problems associated with patterning hydrophilic tether molecules inserted into hydrophilic preformed SAMs are surmounted. The patterned substrates presenting neurotransmitter precursors selectively capture membrane-associated receptors. These advances provide new avenues for fabricating small-molecule arrays. Furthermore, a novel strategy based on a conventional microcontact printing, called chemical lift-off lithography, was invented to overcome the micrometer-scale resolution limits of molecular ink diffusion in soft lithography. Self-assembled monolayers of hydroxyl-terminated alkanethiols, preformed on gold substrates, were selectively removed by oxygen-plasma-treated polymeric stamps in a subtractive stamping process with high pattern fidelity. The covalent interactions formed at the stamp-substrate interface are believed to be responsible for removing not only alkanethiol molecules but also a monolayer of gold atoms from the substrates. A variety of high-resolution patterned features were fabricated, and stamps were cleaned and reused many times without feature deterioration. The remaining SAMs acted as resists for etching exposed gold features. Monolayer backfilling into lifted-off areas enabled patterned protein capture, and 40-nanometer chemical patterns were achieved.

  20. Joint modeling of repeated multivariate cognitive measures and competing risks of dementia and death: a latent process and latent class approach.

    Science.gov (United States)

    Proust-Lima, Cécile; Dartigues, Jean-François; Jacqmin-Gadda, Hélène

    2016-02-10

    Joint models initially dedicated to a single longitudinal marker and a single time-to-event need to be extended to account for the rich longitudinal data of cohort studies. Multiple causes of clinical progression are indeed usually observed, and multiple longitudinal markers are collected when the true latent trait of interest is hard to capture (e.g., quality of life, functional dependency, and cognitive level). These multivariate and longitudinal data also usually have nonstandard distributions (discrete, asymmetric, bounded, etc.). We propose a joint model based on a latent process and latent classes to analyze simultaneously such multiple longitudinal markers of different natures, and multiple causes of progression. A latent process model describes the latent trait of interest and links it to the observed longitudinal outcomes using flexible measurement models adapted to different types of data, and a latent class structure links the longitudinal and cause-specific survival models. The joint model is estimated in the maximum likelihood framework. A score test is developed to evaluate the assumption of conditional independence of the longitudinal markers and each cause of progression given the latent classes. In addition, individual dynamic cumulative incidences of each cause of progression based on the repeated marker data are derived. The methodology is validated in a simulation study and applied on real data about cognitive aging obtained from a large population-based study. The aim is to predict the risk of dementia by accounting for the competing death according to the profiles of semantic memory measured by two asymmetric psychometric tests.

  1. Tuning MEEF for CD control at 65nm node based on Chromeless Phase Lithography (CPL)

    Science.gov (United States)

    Van Den Broeke, Douglas J.; Laidig, Thomas L.; Wampler, Kurt E.; Hsu, Stephen; Shi, Xuelong; Hsu, Michael; Burchard, Paul; Chen, J. Fung

    2002-12-01

    The application of Chromeless Phase Lithography, or 100% transmission attenuated PSM, has been used to demonstrate the potential for achieving quarter-wavelength optical lithography (0.2k1). As the demand to image sub-100nm features reaches to the semiconductor fabrication lines, the need for a robust lithography process capable of meeting high volume requirements is becoming more and more critical. The requirements for high-volume, low-k1 semiconductor manufacturing go beyond wafer imaging technology capable of the process latitude needed for lithography, but also includes data prep software that is capable of applying the details of the imaging technology to the design data, correcting for optical proximity effects, and outputting the necessary mask pattern data. It is also necessary to have a reticle manufacturing infrastructure capable of supporting large volume production with reliability and reasonable turn around time. CPL technology has, by its nature, many elements that make it a strong candidate to meet mass production requirements for 65nm semiconductor technology products. Most important, CPL achieves the resolution enhancement by using a single reticle and does not require a second exposure with a trim mask. The CPL reticle is a variation of the attenuated phase shifting mask, and data preparation for the reticle manufacturing is very similar to what is needed for high-transmission attenuated PSM. It will be shown that as a result of the 100% transmission, the MEEF for CPL masks is very small and in some cases approaches zero. This allows for much larger CD tolerances for the reticle but results in significant limitations on correcting optical proximity effects by using CD bias alone. Methods for correcting through-pitch CD variations with the use of novel CPL pattern designs, bias, and scattering bars will be presented and correlated to wafer imaging results. These results will demonstrate the ability to control through-pitch CD's while maintaining

  2. UV-nanoimprint lithography: structure, materials and fabrication of flexible molds.

    Science.gov (United States)

    Lan, Hongbo; Liu, Hongzhong

    2013-05-01

    Large-area nanopatterning technology has demonstrated high potential which can significantly enhance the performance of a variety of devices and products such as LEDs, solar cells, hard disk drives, laser diodes, wafer-level optics, etc. But various existing patterning technologies cannot well meet industrial-level application requirements in term of high resolution, high throughput, low cost, large patterned areas, and the ability to pattern on non-ideal surfaces or waters. Soft UV-nanoimprint lithography (UV-NIL) by using a flexible mold has been proven to be a cost-effective mass production method for patterning large-area structures up to wafer-level (300 mm) in the micrometer and nanometer scale, fabricating complex 3-D micro/nano structures, especially making large-area patterns on the non-planar surfaces even curved substrates at low-cost and with high throughput. In particular, it provides an ideal solution and a powerful tool for mass producing micro/nanostructures over large areas at low cost for the applications in compound semiconductor optoelectronics and nanophotonic devices, especially for LED patterning. That opens the way for many applications not previously conceptualized or economically feasible. The flexible mold is the most critical elements for soft UV-NIL. The performance of the flexible mold has a decisive effect on the soft UV-NIL in term of resolution, patterning area, throughput, uniformity of the imprinted patterns, and repeatability of multi-imprinting. The key enabler that can fulfill mass production of micro-and nanostructures over large areas by NIL is the continual advancement of mold techniques (structures, materials and fabrication processes) towards higher resolution over a larger area at a lower cost. This paper provides a comprehensive review on the structural types, materials used and fabrication methods of various flexible molds in soft UV-NIL, surveys major progress in various flexible molds, particularly highlights some

  3. Evaporative Lithography in Open Microfluidic Channel Networks

    KAUST Repository

    Lone, Saifullah

    2017-02-24

    We demonstrate a direct capillary-driven method based on wetting and evaporation of various suspensions to fabricate regular two-dimensional wires in an open microfluidic channel through continuous deposition of micro- or nanoparticles under evaporative lithography, akin to the coffee-ring effect. The suspension is gently placed in a loading reservoir connected to the main open microchannel groove on a PDMS substrate. Hydrophilic conditions ensure rapid spreading of the suspension from the loading reservoir to fill the entire channel length. Evaporation during the spreading and after the channel is full increases the particle concentration toward the end of the channel. This evaporation-induced convective transport brings particles from the loading reservoir toward the channel end where this flow deposits a continuous multilayered particle structure. The particle deposition front propagates backward over the entire channel length. The final dry deposit of the particles is thereby much thicker than the initial volume fraction of the suspension. The deposition depth is characterized using a 3D imaging profiler, whereas the deposition topography is revealed using a scanning electron microscope. The patterning technology described here is robust and passive and hence operates without an external field. This work may well become a launching pad to construct low-cost and large-scale thin optoelectronic films with variable thicknesses and interspacing distances.

  4. Evaporative Lithography in Open Microfluidic Channel Networks.

    Science.gov (United States)

    Lone, Saifullah; Zhang, Jia Ming; Vakarelski, Ivan U; Li, Er Qiang; Thoroddsen, Sigurdur T

    2017-03-13

    We demonstrate a direct capillary-driven method based on wetting and evaporation of various suspensions to fabricate regular two-dimensional wires in an open microfluidic channel through continuous deposition of micro- or nanoparticles under evaporative lithography, akin to the coffee-ring effect. The suspension is gently placed in a loading reservoir connected to the main open microchannel groove on a PDMS substrate. Hydrophilic conditions ensure rapid spreading of the suspension from the loading reservoir to fill the entire channel length. Evaporation during the spreading and after the channel is full increases the particle concentration toward the end of the channel. This evaporation-induced convective transport brings particles from the loading reservoir toward the channel end where this flow deposits a continuous multilayered particle structure. The particle deposition front propagates backward over the entire channel length. The final dry deposit of the particles is thereby much thicker than the initial volume fraction of the suspension. The deposition depth is characterized using a 3D imaging profiler, whereas the deposition topography is revealed using a scanning electron microscope. The patterning technology described here is robust and passive and hence operates without an external field. This work may well become a launching pad to construct low-cost and large-scale thin optoelectronic films with variable thicknesses and interspacing distances.

  5. Smartphone Sensors for Stone Lithography Authentication

    Science.gov (United States)

    Schirripa Spagnolo, Giuseppe; Cozzella, Lorenzo; Papalillo, Donato

    2014-01-01

    Nowadays mobile phones include quality photo and video cameras, access to wireless networks and the internet, GPS assistance and other innovative systems. These facilities open them to innovative uses, other than the classical telephonic communication one. Smartphones are a more sophisticated version of classic mobile phones, which have advanced computing power, memory and connectivity. Because fake lithographs are flooding the art market, in this work, we propose a smartphone as simple, robust and efficient sensor for lithograph authentication. When we buy an artwork object, the seller issues a certificate of authenticity, which contains specific details about the artwork itself. Unscrupulous sellers can duplicate the classic certificates of authenticity, and then use them to “authenticate” non-genuine works of art. 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 the related specific artwork. To do this it is necessary, for a single artwork, to find unique, unrepeatable, and unchangeable characteristics. In this article we propose an innovative method for the authentication of stone lithographs. We use the color spots distribution captured by means of a smartphone camera as a non-cloneable texture of the specific artworks and an information management system for verifying it in mobility stone lithography. PMID:24811077

  6. Lithography strategy for 65-nm node

    Science.gov (United States)

    Borodovsky, Yan A.; Schenker, Richard E.; Allen, Gary A.; Tejnil, Edita; Hwang, David H.; Lo, Fu-Chang; Singh, Vivek K.; Gleason, Robert E.; Brandenburg, Joseph E.; Bigwood, Robert M.

    2002-07-01

    Intel will start high volume manufacturing (HVM) of the 65nm node in 2005. Microprocessor density and performance trends will continue to follow Moore's law and cost-effective patterning solutions capable of supporting it have to be found, demonstrated and developed during 2002-2004. Given the uncertainty regarding the readiness and respective capabilities of 157nm and 193nm lithography to support 65nm technology requirements, Intel is developing both lithographic options and corresponding infrastructure with the intent to use both options in manufacturing. Development and use of dual lithographic options for a given technology node in manufacturing is not a new paradigm for Intel: whenever introduction of a new exposure wavelength presented excessive risk to the manufacturing schedule, Intel developed parallel patterning approaches in time for the manufacturing ramp. Both I-line and 248nm patterning solutions were developed and successfully used in manufacturing of the 350nm node at Intel. Similarly, 248nm and 193nm patterning solutions were fully developed for 130nm node high volume manufacturing.

  7. Nanowell surface enhanced Raman scattering arrays fabricated by soft-lithography for label-free biomolecular detections in integrated microfluidics

    Science.gov (United States)

    Liu, Gang L.; Lee, Luke P.

    2005-08-01

    We describe a low-cost, ultrasensitive surface-enhanced Raman scattering (SERS) substrate in microfluidic biochips fabricated by soft lithography. A batch nanofabrication method is developed to create nanopillars structures on a silicon wafer as a master copy of molding, then the complementary nanowells structures on polydimethylsiloxane (PDMS) are created by soft lithography. The selective deposition of Ag thin film on the nanowells is applied to create SERS active sites before the integration with a glass-based microfluidic chip which functions as a sample delivery device and a transparent optical window for SERS spectroscopic imaging. Detections of Rhodamine 6G and adenosine SERS spectra are accomplished by using a 785nm laser with 300μW excitation power. The Raman scattering signal enhancement on the nanowell-based Ag SERS substrate is more than 107 times higher than the control sample (i.e. the smooth Ag layer on PDMS). Fabrication of ultrasensitive nanowell SERS substrate by economical and repeatable soft lithography method can contribute to the future microdevices for high throughput screening of functional genomics, proteomics, and cellular activities.

  8. Production of laccase by Coriolus versicolor and its application in decolorization of dyestuffs : (Ⅰ) Production of laccase by batch and repeated-batch processes

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The production of laccase by Coriolus versicolor wasstudied. The effect of cultivation conditions on laccase productionby Coriolus versicolor was examined to obtain optimal medium andcultivation conditions. Both batch and repeated-batch processeswere performed for laccase production. In repeated-batchfermentation with self-immobilized mycelia, total of 14 cycles wereperformed with laccase activity in the range between 3.4 and 14.8U/ml.

  9. Line Search-Based Inverse Lithography Technique for Mask Design

    Directory of Open Access Journals (Sweden)

    Xin Zhao

    2012-01-01

    Full Text Available As feature size is much smaller than the wavelength of illumination source of lithography equipments, resolution enhancement technology (RET has been increasingly relied upon to minimize image distortions. In advanced process nodes, pixelated mask becomes essential for RET to achieve an acceptable resolution. In this paper, we investigate the problem of pixelated binary mask design in a partially coherent imaging system. Similar to previous approaches, the mask design problem is formulated as a nonlinear program and is solved by gradient-based search. Our contributions are four novel techniques to achieve significantly better image quality. First, to transform the original bound-constrained formulation to an unconstrained optimization problem, we propose a new noncyclic transformation of mask variables to replace the wellknown cyclic one. As our transformation is monotonic, it enables a better control in flipping pixels. Second, based on this new transformation, we propose a highly efficient line search-based heuristic technique to solve the resulting unconstrained optimization. Third, to simplify the optimization, instead of using discretization regularization penalty technique, we directly round the optimized gray mask into binary mask for pattern error evaluation. Forth, we introduce a jump technique in order to jump out of local minimum and continue the search.

  10. Stat-LRC: statistical rules check for variational lithography

    Science.gov (United States)

    Sreedhar, Aswin; Kundu, Sandip

    2010-03-01

    As interconnect densities increase with each technology generation, the lithographic processes required to print all features with acceptable irregularities have become more complex. Restricted design rules (RDR) and modelbased Design for Manufacturability (DFM) guidelines have been added to the existing Design Rule Check (DRC) software to prevent unprintable patterns to be drawn on the mask by predicting their imprint on the wafer. It is evident from analyses of predicted patterns that edge placement errors have a continuous distribution, hence a pass/fail cut-off is somewhat arbitrary. In this paper, we describe a methodology to perform Statistical Lithography Rules Check (Stat-LRC) involving design yield based on interconnect linewidth distribution for variation in lithographic input error sources. In this scheme, a list of error locations indicating polygons that have yield below a user specified threshold are listed. The overall design yield is recovered by trading-off slightly poorer EPE distributions for lines with short runs with excellent ones. The simulation/analysis environment is fully automated and yield recovery improvement has been demonstrated.

  11. Electron beam inspection methods for imprint lithography at 32 nm

    Science.gov (United States)

    Selinidis, Kosta; Thompson, Ecron; Sreenivasan, S. V.; Resnick, Douglas J.

    2009-01-01

    Step and Flash Imprint Lithography redefines nanoimprinting. This novel technique involves the field-by-field deposition and exposure of a low viscosity resist deposited by jetting technology onto the substrate. The patterned mask is lowered into the 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 solid on the substrate. Compatibility with existing CMOS processes requires a mask infrastructure in which resolution, inspection and repair are all addressed. The purpose of this paper is to understand the limitations of inspection at half pitches of 32 nm and below. A 32 nm programmed defect mask was fabricated. Patterns included in the mask consisted of an SRAM Metal 1 cell, dense lines, and dense arrays of pillars. Programmed defect sizes started at 4 nm and increased to 48 nm in increments of 4 nm. Defects in both the mask and imprinted wafers were characterized scanning electron microscopy and the measured defect areas were calculated. These defects were then inspected using a KLA-T eS35 electron beam wafer inspection system. Defect sizes as small as 12 nm were detected, and detection limits were found to be a function of defect type.

  12. 3D Stretchable Arch Ribbon Array Fabricated via Grayscale Lithography

    Science.gov (United States)

    Pang, Yu; Shu, Yi; Shavezipur, Mohammad; Wang, Xuefeng; Mohammad, Mohammad Ali; Yang, Yi; Zhao, Haiming; Deng, Ningqin; Maboudian, Roya; Ren, Tian-Ling

    2016-01-01

    Microstructures with flexible and stretchable properties display tremendous potential applications including integrated systems, wearable devices and bio-sensor electronics. Hence, it is essential to develop an effective method for fabricating curvilinear and flexural microstructures. Despite significant advances in 2D stretchable inorganic structures, large scale fabrication of unique 3D microstructures at a low cost remains challenging. Here, we demonstrate that the 3D microstructures can be achieved by grayscale lithography to produce a curved photoresist (PR) template, where the PR acts as sacrificial layer to form wavelike arched structures. Using plasma-enhanced chemical vapor deposition (PECVD) process at low temperature, the curved PR topography can be transferred to the silicon dioxide layer. Subsequently, plasma etching can be used to fabricate the arched stripe arrays. The wavelike silicon dioxide arch microstructure exhibits Young modulus and fracture strength of 52 GPa and 300 MPa, respectively. The model of stress distribution inside the microstructure was also established, which compares well with the experimental results. This approach of fabricating a wavelike arch structure may become a promising route to produce a variety of stretchable sensors, actuators and circuits, thus providing unique opportunities for emerging classes of robust 3D integrated systems. PMID:27345766

  13. Electrical biomolecule detection using nanopatterned silicon via block copolymer lithography.

    Science.gov (United States)

    Jeong, Chang Kyu; Jin, Hyeong Min; Ahn, Jae-Hyuk; Park, Tae Jung; Yoo, Hyeon Gyun; Koo, Min; Choi, Yang-Kyu; Kim, Sang Ouk; Lee, Keon Jae

    2014-01-29

    An electrical biosensor exploiting a nanostructured semiconductor is a promising technology for the highly sensitive, label-free detection of biomolecules via a straightforward electronic signal. The facile and scalable production of a nanopatterned electrical silicon biosensor by block copolymer (BCP) nano-lithography is reported. A cost-effective and large-area nanofabrication, based on BCP self-assembly and single-step dry etching, is developed for the hexagonal nanohole patterning of thin silicon films. The resultant nanopatterned electrical channel modified with biotin molecules successfully detects the two proteins, streptavidin and avidin, down to nanoscale molarities (≈1 nm). The nanoscale pattern comparable to the Debye screening length and the large surface area of the three-dimensional silicon nanochannel enable excellent sensitivity and stability. A device simulation confirms that the nanopatterned structure used in this work is effective for biomolecule detection. This approach relying on the scalable self-assembly principle offers a high-throughput manufacturing process for clinical lab-on-a-chip diagnoses and relevant biomolecular studies. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Highly hydrophobic materials for ArF immersion lithography

    Science.gov (United States)

    Takebe, Yoko; Shirota, Naoko; Sasaki, Takashi; Murata, Koichi; Yokokoji, Osamu

    2008-03-01

    In immersion lithography, the impact of water on resist performance and the possibility of damage to the lens by the components eluted from the resist material are seriously concern. And much work has shown that controlling the water-resist interface is critical to enabling high scan rates. Many topcoat materials have been developed to control the aforementioned interfacial properties. Developable topcoats have been particularly investigated as suitable candidates for its applicability to the resist developing process. Achieving the balance between the low surface energy required for higher receding contact angle and the base solubility for topcoat removal is challenging. We have already reported FUGU polymer which have partially fluorinated monocyclic structure and hexafluoroalcohol(HFA) group and showed that its developer solubility was excellent but hydrophobicity was insufficient for high scan rate. We have also reported that co-polymers of FUGU and highly fluorinated monomers which have perfluorinated cyclic structure had sufficient hydrophobicity but lower developer solubility. We have found that it was difficult to use these copolymers in themselves as topcoat. But by blending of moderate amount of these copolymers into FUGU polymer, we have finally obtained highly hydrophobic developer-soluble topcoat. Hydrophobicity can be controlled by blending ratio. Furthermore we have newly successfully synthesized a series of fluoropolymers, FIT polymer partially fluorinated monocyclic structure and having carboxylic acid group as developer-soluble unit. When FIT polymer as well as FUGU polymer, was blended to highly hydrophobic copolymer, the blended polymer also showed higher hydrophobicity keeping sufficient developer solubility.

  15. Interdigitated multicolored bioink micropatterns by multiplexed polymer pen lithography.

    Science.gov (United States)

    Brinkmann, Falko; Hirtz, Michael; Greiner, Alexandra M; Weschenfelder, Markus; Waterkotte, Björn; Bastmeyer, Martin; Fuchs, Harald

    2013-10-11

    Multiplexing, i.e., the application and integration of more than one ink in an interdigitated microscale pattern, is still a challenge for microcontact printing (μCP) and similar techniques. On the other hand there is a strong demand for interdigitated patterns of more than one protein on subcellular to cellular length scales in the lower micrometer range in biological experiments. Here, a new integrative approach is presented for the fabrication of bioactive microarrays and complex multi-ink patterns by polymer pen lithography (PPL). By taking advantage of the strength of microcontact printing (μCP) combined with the spatial control and capability of precise repetition of PPL in an innovative way, a new inking and writing strategy is introduced for PPL that enables true multiplexing within each repetitive subpattern. Furthermore, a specific ink/substrate platform is demonstrated that can be used to immobilize functional proteins and other bioactive compounds over a biotin-streptavidin approach. This patterning strategy aims specifically at application by cell biologists and biochemists addressing a wide range of relevant pattern sizes, easy pattern generation and adjustment, the use of only biofriendly, nontoxic chemicals, and mild processing conditions during the patterning steps. The retained bioactivity of the fabricated cm(2) area filling multiprotein patterns is demonstrated by showing the interaction of fibroblasts and neurons with multiplexed structures of fibronectin and laminin or laminin and ephrin, respectively.

  16. Master masks for big patterns by electron-beam lithography

    Science.gov (United States)

    Zlobin, Vladimir A.; Mamonov, V. I.; Vasiljeva, Olga G.

    1995-05-01

    Modern technologies for power semiconductor devices, laser and micro optics, micromechanics requires microlithography of patterns having a large are up to 100 cm2 with complicate precise drawing. The electron beam lithography (EBL) tools with variable shape beam have good prospects for this purpose, but their application has a few problems in case of the tasks pointed above. The main problems are a great volume of information and a large exposure time of such patterns. We propose the system for preparation of the exposure data having more than 100 MB volume that consists from set of personal computers, network adapters, and software. The preparation of graphic information and exposure strategy are presented. The optimum exposure conditions are determined by program modeling the exposure process in dependence on the statistic distribution of sizes of EBL figures. Our method permits to decrease the exposure time in several times under certain conditions and brings that nearer to theoretical limit Tmin equals SD/IBmax, where Tmin is minimum exposure time, S is exposure area, D is dose density, IBmax is maximum beam current. This approach is valid if the basic factor limiting the writing speed is IBmax. The developed computer system and writing strategy was applied us for mask making on modified ZBA-21 tool. These masks were meant for production of power semiconductor and laser optics devices.

  17. W-CMOS blanking device for projection multibeam lithography

    Science.gov (United States)

    Jurisch, Michael; Irmscher, Mathias; Letzkus, Florian; Eder-Kapl, Stefan; Klein, Christof; Loeschner, Hans; Piller, Walter; Platzgummer, Elmar

    2010-05-01

    As the designs of future mask nodes become more and more complex the corresponding pattern writing times will rise significantly when using single beam writing tools. Projection multi-beam lithography [1] is one promising technology to enhance the throughput compared to state of the art VSB pattern generators. One key component of the projection multi-beam tool is an Aperture Plate System (APS) to form and switch thousands of individual beamlets. In our present setup a highly parallel beam is divided into 43,008 individual beamlets by a Siaperture- plate. These micrometer sized beams pass through larger openings in a blanking-plate and are individually switched on and off by applying a voltage to blanking-electrodes which are placed around the blanking-plate openings. A charged particle 200x reduction optics demagnifies the beamlet array to the substrate. The switched off beams are filtered out in the projection optics so that only the beams which are unaffected by the blanking-plate are projected to the substrate with 200x reduction. The blanking-plate is basically a CMOS device for handling the writing data. In our work the blanking-electrodes are fabricated using CMOS compatible add on processes like SiO2-etching or metal deposition and structuring. A new approach is the implementation of buried tungsten electrodes for beam blanking.

  18. Plasmonic nanostructures fabricated using nanosphere-lithography, soft-lithography and plasma etching

    Directory of Open Access Journals (Sweden)

    Manuel R. Gonçalves

    2011-08-01

    Full Text Available We present two routes for the fabrication of plasmonic structures based on nanosphere lithography templates. One route makes use of soft-lithography to obtain arrays of epoxy resin hemispheres, which, in a second step, can be coated by metal films. The second uses the hexagonal array of triangular structures, obtained by evaporation of a metal film on top of colloidal crystals, as a mask for reactive ion etching (RIE of the substrate. In this way, the triangular patterns of the mask are transferred to the substrate through etched triangular pillars. Making an epoxy resin cast of the pillars, coated with metal films, allows us to invert the structure and obtain arrays of triangular holes within the metal. Both fabrication methods illustrate the preparation of large arrays of nanocavities within metal films at low cost.Gold films of different thicknesses were evaporated on top of hemispherical structures of epoxy resin with different radii, and the reflectance and transmittance were measured for optical wavelengths. Experimental results show that the reflectivity of coated hemispheres is lower than that of coated polystyrene spheres of the same size, for certain wavelength bands. The spectral position of these bands correlates with the size of the hemispheres. In contrast, etched structures on quartz coated with gold films exhibit low reflectance and transmittance values for all wavelengths measured. Low transmittance and reflectance indicate high absorbance, which can be utilized in experiments requiring light confinement.

  19. Plasmonic nanostructures fabricated using nanosphere-lithography, soft-lithography and plasma etching.

    Science.gov (United States)

    Gonçalves, Manuel R; Makaryan, Taron; Enderle, Fabian; Wiedemann, Stefan; Plettl, Alfred; Marti, Othmar; Ziemann, Paul

    2011-01-01

    We present two routes for the fabrication of plasmonic structures based on nanosphere lithography templates. One route makes use of soft-lithography to obtain arrays of epoxy resin hemispheres, which, in a second step, can be coated by metal films. The second uses the hexagonal array of triangular structures, obtained by evaporation of a metal film on top of colloidal crystals, as a mask for reactive ion etching (RIE) of the substrate. In this way, the triangular patterns of the mask are transferred to the substrate through etched triangular pillars. Making an epoxy resin cast of the pillars, coated with metal films, allows us to invert the structure and obtain arrays of triangular holes within the metal. Both fabrication methods illustrate the preparation of large arrays of nanocavities within metal films at low cost.Gold films of different thicknesses were evaporated on top of hemispherical structures of epoxy resin with different radii, and the reflectance and transmittance were measured for optical wavelengths. Experimental results show that the reflectivity of coated hemispheres is lower than that of coated polystyrene spheres of the same size, for certain wavelength bands. The spectral position of these bands correlates with the size of the hemispheres. In contrast, etched structures on quartz coated with gold films exhibit low reflectance and transmittance values for all wavelengths measured. Low transmittance and reflectance indicate high absorbance, which can be utilized in experiments requiring light confinement.

  20. Wafer-Scale Nanopillars Derived from Block Copolymer Lithography for Surface-Enhanced Raman Spectroscopy

    DEFF Research Database (Denmark)

    Li, Tao; Wu, Kaiyu; Rindzevicius, Tomas

    2016-01-01

    We report a novel nanofabrication process via block copolymer lithography using solvent vapor annealing. The nanolithography process is facile and scalable, enabling fabrication of highly ordered periodic patterns over entire wafers as substrates for surface-enhanced Raman spectroscopy (SERS). Di...... deviation across 4 cm, and 6.5% relative standard deviation over 5 × 5 mm2 surface area, as well as a very low SERS background. The as-prepared SERS substrate, with a good enhancement and large-area uniformity, is promising for practical SERS sensing applications....

  1. Fabrication of Si/SiO2 Superlattice Microwire Array Solar Cells Using Microsphere Lithography

    Directory of Open Access Journals (Sweden)

    Shigeru Yamada

    2016-01-01

    Full Text Available A fabrication process for silicon/silicon dioxide (Si/SiO2 superlattice microwire array solar cells was developed. The Si/SiO2 superlattice microwire array was fabricated using a microsphere lithography process with polystyrene particles. The solar cell shows a photovoltaic effect and an open-circuit voltage of 128 mV was obtained. The limiting factors of the solar cell performance were investigated from the careful observations of the solar cell structures. We also investigated the influence of the microwire array structure on light trapping in the solar cells.

  2. Expanded complexity of unstable repeat diseases

    OpenAIRE

    Polak, Urszula; McIvor, Elizabeth; Dent, Sharon Y.R.; Wells, Robert D.; Napierala, Marek.

    2012-01-01

    Unstable Repeat Diseases (URDs) share a common mutational phenomenon of changes in the copy number of short, tandemly repeated DNA sequences. More than 20 human neurological diseases are caused by instability, predominantly expansion, of microsatellite sequences. Changes in the repeat size initiate a cascade of pathological processes, frequently characteristic of a unique disease or a small subgroup of the URDs. Understanding of both the mechanism of repeat instability and molecular consequen...

  3. Transcriptional responses to loss or gain of function of the leucine-rich repeat kinase 2 (LRRK2) gene uncover biological processes modulated by LRRK2 activity

    Science.gov (United States)

    Nikonova, Elena V.; Xiong, Yulan; Tanis, Keith Q.; Dawson, Valina L.; Vogel, Robert L.; Finney, Eva M.; Stone, David J.; Reynolds, Ian J.; Kern, Jonathan T.; Dawson, Ted M.

    2012-01-01

    Mutations in the leucine-rich repeat kinase 2 gene (LRRK2) are the most common genetic cause of Parkinson's disease (PD) and cause both autosomal dominant familial and sporadic PD. Currently, the physiological and pathogenic activities of LRRK2 are poorly understood. To decipher the biological functions of LRRK2, including the genes and pathways modulated by LRRK2 kinase activity in vivo, we assayed genome-wide mRNA expression in the brain and peripheral tissues from LRRK2 knockout (KO) and kinase hyperactive G2019S (G2019S) transgenic mice. Subtle but significant differences in mRNA expression were observed relative to wild-type (WT) controls in the cortex, striatum and kidney of KO animals, but only in the striatum in the G2019S model. In contrast, robust, consistent and highly significant differences were identified by the direct comparison of KO and G2019S profiles in the cortex, striatum, kidney and muscle, indicating opposite effects on mRNA expression by the two models relative to WT. Ribosomal and glycolytic biological functions were consistently and significantly up-regulated in LRRK2 G2019S compared with LRRK2 KO tissues. Genes involved in membrane-bound organelles, oxidative phosphorylation, mRNA processing and the endoplasmic reticulum were down-regulated in LRRK2 G2019S mice compared with KO. We confirmed the expression patterns of 35 LRRK2-regulated genes using quantitative reverse transcription polymerase chain reaction. These findings provide the first description of the transcriptional responses to genetically modified LRRK2 activity and provide preclinical target engagement and/or pharmacodynamic biomarker strategies for LRRK2 and may inform future therapeutic strategies for LRRK2-associated PD. PMID:21972245

  4. Key techniques of DMD in laser lithography%激光光刻中数字微镜器件关键技术研究

    Institute of Scientific and Technical Information of China (English)

    黄新栋; 尹涛

    2011-01-01

    在无掩模激光光刻系统中,TI(Texa instrument,德州仪器)公司基于DLP(digital light processing,数字光处理)架构的DMD(digital micromirror device,数字微镜器件)系统已经得到应用,但是存在光刻图像质量和光刻速度无法提高等瓶颈.提出采用单片FPGA控制DMD的架构,使得微镜锁定时间自由可控,在成像质量上高于DLP架构下的光刻成像质量,同时具备的同步功能和高帧频特性可大大提高光刻速度.%The maskless laser lithography system using digital micromirror device (DMD) based on digital light processing (DLP) structure was used widely, but the lithography image quality and lithography speed should be improved. A new method for solving these problems is proposed, which adopts FPGA to control DMD. The new structure enables the flexible control of micromirror lock and improves the system lithography image quality accordingly. The synchronization signal and high frame rate of the new structure improve system lithography speed.

  5. Optical characterisation of photonic wire and photonic crystal waveguides fabricated using nanoimprint lithography

    DEFF Research Database (Denmark)

    Borel, Peter Ingo; Frandsen, Lars Hagedorn; Lavrinenko, Andrei;

    2006-01-01

    We have characterised photonic-crystal and photonic-wire waveguides fabricated by thermal nanoimprint lithography. The structures, with feature sizes down below 20 nm, are benchmarked against similar structures defined by direct electron beam lithography....

  6. Pattern-integrated interference lithography: prospects for nano- and microelectronics.

    Science.gov (United States)

    Leibovici, Matthieu C R; Burrow, Guy M; Gaylord, Thomas K

    2012-10-08

    In recent years, limitations in optical lithography have challenged the cost-effective manufacture of nano- and microelectronic chips. Spatially regular designs have been introduced to improve manufacturability. However, regular designed layouts typically require an interference step followed by a trim step. These multiple steps increase cost and reduce yield. In the present work, Pattern-Integrated Interference Lithography (PIIL) is introduced to address this problem. PIIL is the integration of interference lithography and superposed pattern mask imaging, combining the interference and the trim into a single-exposure step. Example PIIL implementations and experimental demonstrations are presented. The degrees of freedom associated with the source, pattern mask, and Fourier filter designs are described.

  7. Designing large scale chiral metamaterials by nanosphere shadowing lithography

    Science.gov (United States)

    He, Yizhuo; Zhao, Yiping

    2016-09-01

    A scalable nanofabrication technique for chiral metamaterials is presented, which combines the dynamic shadowing growth and self-assembled nanosphere monolayers, and is also known as nanosphere shadowing lithography. We have developed two strategies based on nanosphere shadowing lithography to prepare chiral nanostructures. The first strategy is to create a quasi-three-dimensional single-layer fan-shaped chiral nanostructure on nanospheres with one plasmonic material. The second strategy is to create three-dimensional multi-layers helical nanostructures with one plasmonic material and one dielectric material. Both strategies can produce large-area chiral nanostructures with strong chiral optical response, which makes nanosphere shadowing lithography suitable for producing chiral metamaterial based devices such as an ultrathin narrow-band circular polarizer.

  8. Recent developments of x-ray lithography in Canada

    Science.gov (United States)

    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.

  9. Scalable Fourier transform system for instantly structured illumination in lithography.

    Science.gov (United States)

    Ye, Yan; Xu, Fengchuan; Wei, Guojun; Xu, Yishen; Pu, Donglin; Chen, Linsen; Huang, Zhiwei

    2017-05-15

    We report the development of a unique scalable Fourier transform 4-f system for instantly structured illumination in lithography. In the 4-f system, coupled with a 1-D grating and a phase retarder, the ±1st order of diffracted light from the grating serve as coherent incident sources for creating interference patterns on the image plane. By adjusting the grating and the phase retarder, the interference fringes with consecutive frequencies, as well as their orientations and phase shifts, can be generated instantly within a constant interference area. We demonstrate that by adapting this scalable Fourier transform system into lithography, the pixelated nano-fringe arrays with arbitrary frequencies and orientations can be dynamically produced in the photoresist with high variation resolution, suggesting its promising application for large-area functional materials based on space-variant nanostructures in lithography.

  10. Fabrication of blazed gratings for X-ray spectroscopy using substrate conformal imprint lithography

    Science.gov (United States)

    McCoy, Jake; Verschuuren, Marc; Lopez, Gerald; Zhang, Ningxiao; McEntaffer, Randall

    2017-08-01

    The majority of spectral lines relevant in high energy astrophysics exist at soft X-ray energies, where gratings dominate over microcalorimeters. Next-generation reflection gratings have been identified as a key technology to improve the spectroscopic capabilities of future X-ray observatories. Currently, the grating fabrication process centers on the production of a large-area (72 cm2) master template through techniques in electron-beam lithography, plasma etching and anisotropic wet etching in single-crystal Si. Then, many replicas are produced to populate a grating array, which intercepts and disperses the radiation coming to a focus in a Wolter-I telescope. Of importance is implenting a replication procedure that preserves the fidelity of the master grating template at a low cost. Traditionally, the Si master template has been used to stamp directly into a UV-curable resist coated on a fused silica substrate through the process of nanoimprint lithography (UV-NIL). Though the high stiffness of Si allows the desired inverse of the original pattern to be imprinted with high resolution, difficulties arise especially when imprinting over a large area. Substrate conformal imprint lithography (SCIL) is a relatively new commercial process intended to evade these problems. In contrast to UV-NIL, the SCIL process uses a flexible stamp formed from the master template for imprinting. The flexible stamp carries the inverse of the original pattern in a modified silicone rubber, which has increased stiffness compared to standard silicone used in soft lithography processes. This enables the positive of original pattern to be imprinted sequentially with high resolution while confroming to the bow of the substrate and reducing damage due to particulate contaminants. The desired inverse of the original pattern can be imprinted with SCIL by forming a second flexible stamp from the initial flexible stamp. Further, SCIL is compatible with an inorganic imprint resist that has been

  11. Advanced low-complexity compression for maskless lithography data

    Science.gov (United States)

    Dai, Vito; Zakhor, Avideh

    2004-05-01

    A direct-write maskless lithography system using 25nm for 50nm feature sizes requires data rates of about 10 Tb/s to maintain a throughput of one wafer per minute per layer achieved by today"s optical lithography systems. In a previous paper, we presented an architecture that achieves this data rate contingent on 25 to 1 compression of lithography data, and on implementation of a real-time decompressor fabricated on the same chip as a massively parallel array of lithography writers for 50 nm feature sizes. A number of compression techniques, including JBIG, ZIP, the novel 2D-LZ, and BZIP2 were demonstrated to achieve sufficiently high compression ratios on lithography data to make the architecture feasible, although no single technique could achieve this for all test layouts. In this paper we present a novel lossless compression algorithm called Context Copy Combinatorial Code (C4) specifically tailored for lithography data. It successfully combines the advantages of context-based modeling in JBIG and copying in ZIP to achieve higher compression ratios across all test layouts. As part of C4, we have developed a low-complexity binary entropy coding technique called combinatorial coding which is simultaneously as efficient as arithmetic coding and as fast as Huffman coding. Compression results show C4 outperforms JBIG, ZIP, BZIP2, and 2D-LZ, and achieves lossless compression ratios greater than 22 for binary layout image data, and greater than 14 for grey-pixel image data. The tradeoff between decoder buffer size, which directly affects implementation complexity and compression ratio is examined. For the same buffer size, C4 achieves higher compression than LZ77, ZIP, and BZIP2.

  12. Extending analog design scaling to sub-wavelength lithography: co-optimization of RET and photomasks

    Science.gov (United States)

    Parikh, Ashesh; Dorris, Siew; Smelko, Tom; Walbrick, Walter; Mahalingam, Pushpa; Arch, John; Green, Kent; Garg, Vishal; Buck, Peter; West, Craig

    2011-04-01

    The mask requirements for 110nm half-node BiCMOS process were analyzed with the goal to meet customer needs at lower cost and shorter cycle times. The key differentiating features for this technology were high density CMOS libraries along with high-power Bipolar, LDMOS and DECMOS components. The high voltage components were characterized by transistors that formed cylindrical junctions. The presence of curved features in the data is particularly detrimental to the write time on a 50KeV vector mask writer. The mask write times have a direct impact on both mask cost and cycle time. Design rules also permit rectangular or stretched contacts to allow conductance of high currents. To meet customer needs but still manage the computational lithography overhead as well as the patterning process performance, this process was evaluated in terms of computational lithography and photomask co-optimization for the base-line 50KeV vector and laser mask-writers. Due to the differences in imaging and processing of the different mask writing systems, comparative analysis of critical dimension (CD) performance both in terms of linearity and pitch was done. Differences in imaging on silicon due to mask fidelity were also expected and characterized. The required changes in OPC necessary to switch to the new mask process were analyzed.

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

    Science.gov (United States)

    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…

  14. V-groove plasmonic waveguides fabricated by nanoimprint lithography

    DEFF Research Database (Denmark)

    Fernandez-Cuesta, I.; Nielsen, R.B.; Boltasseva, Alexandra

    2007-01-01

    Propagation of channel plasmon-polariton modes in the bottom of a metal V groove has been recently demonstrated. It provides a unique way of manipulating light at nanometer length scale. In this work, we present a method based on nanoimprint lithography that allows parallel fabrication of integra......Propagation of channel plasmon-polariton modes in the bottom of a metal V groove has been recently demonstrated. It provides a unique way of manipulating light at nanometer length scale. In this work, we present a method based on nanoimprint lithography that allows parallel fabrication...

  15. Mask tuning for process window improvement

    Science.gov (United States)

    Buttgereit, Ute; Birkner, Robert; Graitzer, Erez; Cohen, Avi; Triulzi, Benedetta; Romeo, Carmelo

    2011-03-01

    For the next years optical lithography stays at 193nm with a numerical aperture of 1.35. Mask design becomes more complex, mask and lithography specifications tighten. The k1 factor comes close to 0.25 which leads to a tremendously increased Mask Error Enhancement Factor (MEEF). This means that CD errors on mask are getting highly amplified on wafer. Process control becomes more important than ever. Accurate process control is a key factor to success to maintain a high yield in chip production. One key parameter to ensure a high and reliable functionality for any integrated circuit is the critical dimension uniformity (CDU). There are different contributors which impact the intra-field CD performance at wafer such as mask CD uniformity, scanner fingerprint, resist process etc. In the present work we focus on improvement of mask CD signature which is one of the main contributors to intra-field CD uniformity. The mask CD uniformity has been measured by WLCD32 which measures the CD based on proven aerial image technology. Based on this CD input the CD uniformity was corrected by CDC200TM and afterwards verified by WLCD32 measurement. The CDC200TM tool utilizes an ultrafast femto-second laser to write intra-volume shading elements (Shade-In ElementsTM) inside the bulk material of the mask. By adjusting the density of the shading elements, the light transmission through the mask is locally changed in a manner that improves wafer CDU when the corrected mask is printed. Additionally, the impact of the improved CD uniformity on the lithography process window was investigated. Goal of the work is to establish a process flow for mask CD uniformity improvement based on mask CD metrology by WLCD32 and mask CD uniformity control by CDC200TM and to verify its impact on the lithography process window. The proposed process flow will be validated by wafer prints. It was shown that the WLCD32 has an excellent correlation to wafer data and an outstanding CD repeatability. It provides

  16. Electrochemical nanoimprint lithography: when nanoimprint lithography meets metal assisted chemical etching.

    Science.gov (United States)

    Zhang, Jie; Zhang, Lin; Han, Lianhuan; Tian, Zhao-Wu; Tian, Zhong-Qun; Zhan, Dongping

    2017-06-08

    The functional three dimensional micro-nanostructures (3D-MNS) play crucial roles in integrated and miniaturized systems because of the excellent physical, mechanical, electric and optical properties. Nanoimprint lithography (NIL) has been versatile in the fabrication of 3D-MNS by pressing thermoplastic and photocuring resists into the imprint mold. However, direct nanoimprint on the semiconductor wafer still remains a great challenge. On the other hand, considered as a competitive fabrication method for erect high-aspect 3D-MNS, metal assisted chemical etching (MacEtch) can remove the semiconductor by spontaneous corrosion reaction at the metal/semiconductor/electrolyte 3-phase interface. Moreover, it was difficult for MacEtch to fabricate multilevel or continuously curved 3D-MNS. The question of the consequences of NIL meeting the MacEtch is yet to be answered. By employing a platinum (Pt) metalized imprint mode, we demonstrated that using electrochemical nanoimprint lithography (ECNL) it was possible to fabricate not only erect 3D-MNS, but also complex 3D-MNS with multilevel stages with continuously curved surface profiles on a gallium arsenide (GaAs) wafer. A concave microlens array with an average diameter of 58.4 μm and height of 1.5 μm was obtained on a ∼1 cm(2)-area GaAs wafer. An 8-phase microlens array was fabricated with a minimum stage of 57 nm and machining accuracy of 2 nm, presenting an excellent optical diffraction property. Inheriting all the advantages of both NIL and MacEtch, ECNL has prospective applications in the micro/nano-fabrications of semiconductors.

  17. Fabrication of Two-Dimensional Photonic Crystals with Triangular Rods by Single-Exposure Holographic Lithography

    Institute of Scientific and Technical Information of China (English)

    PU Yi-Ying; LIANG Guan-Quan; MAO Wei-Dong; DONG Jian-Wen; WANG He-Zhou

    2007-01-01

    We demonstrate a single-exposure holographic fabrication of two-dimensional photonic crystal witn roundband gaps exist in this structure.Our experimental results show that holographic lithography can be used to fabricate photonic crystals not only with various lattice structures but also with various kinds of structures of the atoms,to obtain absolute band gaps or a particular band gap structure.Furthermore,the single-exposure holographic method not only makes the fabrication process simple and convenient but also makes the structures of the atoms more perfect.

  18. Single-stripe tunable laser with chirped sampled gratings fabricated by nanoimprint lithography

    Science.gov (United States)

    Yoshinaga, Hiroyuki; Yanagisawa, Masaki; Kaneko, Toshimitsu; Akiyama, Kan; Tajima, Mikio; Shoji, Daisei; Fujii, Takuya; Shoji, Hajime

    2014-08-01

    The fabrication of diffraction gratings of a chirped sampled gratings distributed reflector (CSG-DR) laser by nanoimprint lithography (NIL) has been demonstrated. The diffraction gratings with highly uniform linewidth and period have been successfully fabricated by the combination of the reverse-tone NIL and precise etching techniques. The CSG-DR laser fabricated by NIL shows a sufficiently wide tuning range of 40 nm as we designed. The results of this study indicate that our fabrication process for the sampled gratings utilizing the NIL technique has a high potential for the fabrication of a CSG-DR laser.

  19. Plasmonic V-groove waveguides with Bragg grating filters via nanoimprint lithography

    DEFF Research Database (Denmark)

    Smith, Cameron L. C.; Desiatov, Boris; Goykmann, Ilya

    2012-01-01

    We demonstrate spectral filtering with state-of-the-art Bragg gratings in plasmonic V-groove waveguides fabricated by wafer scale processing based on nanoimprint lithography. Transmission spectra of the devices having 16 grating periods exhibit spectral rejection of the channel plasmon polaritons...... with 8.2 dB extinction ratio and -3 dB bandwidth of Δλ = 39.9 nm near telecommunications wavelengths. Near-field scanning optical microscopy measurements verify spectral reflection from the grating structures, and the oscillations of propagating modes along grating-less V- grooves correspond well...

  20. On the mechanism of low-pressure imprint lithography: capillarity vs viscous flow.

    Science.gov (United States)

    Khang, Dahl-Young; Lee, Hong H

    2008-05-20

    Dominant mechanisms in low-pressure imprint lithography processes have been identified for the regimes that are definable in terms of applied pressure, temperature, and mold material characteristics. Capillarity is found to be the dominant mechanism at high temperature and low pressure when stiff, hard molds are used. In the case of flexible thin-film ( approximately 20 microm) molds, both the capillarity and the viscous flow are involved. Both mechanisms are operative in the initial stage of the imprinting, but the capillarity takes over as time progresses.

  1. 193nm immersion lithography for high-performance silicon photonic circuits

    Science.gov (United States)

    Selvaraja, Shankar K.; Winroth, Gustaf; Locorotondo, Sabrina; Murdoch, Gayle; Milenin, Alexey; Delvaux, Christie; Ong, Patrick; Pathak, Shibnath; Xie, Weiqiang; Sterckx, Gunther; Lepage, Guy; Van Thourhout, Dries; Bogaerts, Wim; Van Campenhout, Joris; Absil, Philippe

    2014-04-01

    Large-scale photonics integration has been proposed for many years to support the ever increasing requirements for long and short distance communications as well as package-to-package interconnects. Amongst the various technology options, silicon photonics has imposed itself as a promising candidate, relying on CMOS fabrication processes. While silicon photonics can share the technology platform developed for advanced CMOS devices it has specific dimension control requirements. Though the device dimensions are in the order of the wavelength of light used, the tolerance allowed can be less than 1% for certain devices. Achieving this is a challenging task which requires advanced patterning techniques along with process control. Another challenge is identifying an overlapping process window for diverse pattern densities and orientations on a single layer. In this paper, we present key technology challenges faced when using optical lithography for silicon photonics and advantages of using the 193nm immersion lithography system. We report successful demonstration of a modified 28nm- STI-like patterning platform for silicon photonics in 300mm Silicon-On-Insulator wafer technology. By careful process design, within-wafer CD variation (1sigma) of 20 % from the best propagation loss reported for this cross-section fabricated using e-beam lithography. By using a single-mode low-confinement waveguide geometry the loss is further reduced to ~0.12 dB/cm. Secondly, we present improvement in within-device phase error in wavelength selective devices, a critical parameter which is a direct measure of line-width uniformity improvement due to the 193nm immersion system. In addition to these superior device performances, the platform opens scenarios for designing new device concepts using sub-wavelength features. By taking advantage of this, we demonstrate a cost-effective robust single-etch sub-wavelength structure based fiber-chip coupler with a coupling efficiency of 40 % and high

  2. Dopamine-assisted rapid fabrication of nanoscale protein arrays by colloidal lithography.

    Science.gov (United States)

    Ogaki, Ryosuke; Bennetsen, Dines T; Bald, Ilko; Foss, Morten

    2012-06-12

    The development of cost-effective methodologies for the precise nanometer-scale positioning of biomolecules permits the low-cost production of various biofunctional devices for a range of biomedical and nanotechnological applications. By combining colloidal lithography and the mussel-inspired multifunctional polydopamine coating, we present a novel parallel benchtop method that allows rapid nanoscale patterning of proteins without the need for electrically powered equipment in the fabrication process. The PDA-immobilized binary nanopattern consisting of BSA surrounded by PLL-g-PEG is fabricated over a large area, and the integrity of the pattern is confirmed using AFM and FM.

  3. Wafer Surface Charge Reversal as a Method of Simplifying Nanosphere Lithography for Reactive Ion Etch Texturing of Solar Cells

    Directory of Open Access Journals (Sweden)

    Daniel Inns

    2007-01-01

    Full Text Available A simplified nanosphere lithography process has been developed which allows fast and low-waste maskings of Si surfaces for subsequent reactive ion etching (RIE texturing. Initially, a positive surface charge is applied to a wafer surface by dipping in a solution of aluminum nitrate. Dipping the positive-coated wafer into a solution of negatively charged silica beads (nanospheres results in the spheres becoming electrostatically attracted to the wafer surface. These nanospheres form an etch mask for RIE. After RIE texturing, the reflection of the surface is reduced as effectively as any other nanosphere lithography method, while this batch process used for masking is much faster, making it more industrially relevant.

  4. The 28S-18S rDNA intergenic spacer from Crithidia fasciculata: repeated sequences, length heterogeneity, putative processing sites and potential interactions between U3 small nucleolar RNA and the ribosomal RNA precursor.

    Science.gov (United States)

    Schnare, M N; Collings, J C; Spencer, D F; Gray, M W

    2000-09-15

    In Crithidia fasciculata, the ribosomal RNA (rRNA) gene repeats range in size from approximately 11 to 12 kb. This length heterogeneity is localized to a region of the intergenic spacer (IGS) that contains tandemly repeated copies of a 19mer sequence. The IGS also contains four copies of an approximately 55 nt repeat that has an internal inverted repeat and is also present in the IGS of Leishmania species. We have mapped the C.fasciculata transcription initiation site as well as two other reverse transcriptase stop sites that may be analogous to the A0 and A' pre-rRNA processing sites within the 5' external transcribed spacer (ETS) of other eukaryotes. Features that could influence processing at these sites include two stretches of conserved primary sequence and three secondary structure elements present in the 5' ETS. We also characterized the C.fasciculata U3 snoRNA, which has the potential for base-pairing with pre-rRNA sequences. Finally, we demonstrate that biosynthesis of large subunit rRNA in both C. fasciculata and Trypanosoma brucei involves 3'-terminal addition of three A residues that are not present in the corresponding DNA sequences.

  5. Adaptive Optics for EUV Lithography: Phase Retrieval for Wavefront Metrology

    NARCIS (Netherlands)

    Polo, A.

    2014-01-01

    In the semiconductor industry, optical lithography is presently the most widespread technology used to print a geometrical pattern on a semiconductor wafer. Because of the plans imposed by the International Technology Roadmap for Semiconductors (ITRS) for more powerful and smaller chips, new printin

  6. From 2D Lithography to 3D Patterning

    NARCIS (Netherlands)

    Van Zeijl, H.W.; Wei, J.; Shen, C.; Verhaar, T.M.; Sarro, P.M.

    2010-01-01

    Lithography as developed for IC device fabrication is a high volume high accuracy patterning technology with strong 2 dimensional (2D) characteristics. This 2D nature makes it a challenge to integrate this technology in a 3 dimensional (3D) manufacturing environment. This article addresses the perfo

  7. From 2D Lithography to 3D Patterning

    NARCIS (Netherlands)

    Van Zeijl, H.W.; Wei, J.; Shen, C.; Verhaar, T.M.; Sarro, P.M.

    2010-01-01

    Lithography as developed for IC device fabrication is a high volume high accuracy patterning technology with strong 2 dimensional (2D) characteristics. This 2D nature makes it a challenge to integrate this technology in a 3 dimensional (3D) manufacturing environment. This article addresses the

  8. Adaptive Optics for EUV Lithography: Phase Retrieval for Wavefront Metrology

    NARCIS (Netherlands)

    Polo, A.

    2014-01-01

    In the semiconductor industry, optical lithography is presently the most widespread technology used to print a geometrical pattern on a semiconductor wafer. Because of the plans imposed by the International Technology Roadmap for Semiconductors (ITRS) for more powerful and smaller chips, new printin

  9. Receding contact lines: From sliding drops to immersion lithography

    NARCIS (Netherlands)

    Winkels, K.G.; Peters, I.R.; Evangelista, F.; Riepen, M.; Daerr, A.; Limat, L.; Snoeijer, J.H.

    2011-01-01

    Instabilities of receding contact lines often occur through the formation of a corner with a very sharp tip. These dewetting structures also appear in the technology of Immersion Lithography, where water is put between the lens and the silicon wafer to increase the optical resolution. In this paper

  10. Beyond EUV lithography: a comparative study of efficient photoresists' performance.

    Science.gov (United States)

    Mojarad, Nassir; Gobrecht, Jens; Ekinci, Yasin

    2015-03-18

    Extreme ultraviolet (EUV) lithography at 13.5 nm is the main candidate for patterning integrated circuits and reaching sub-10-nm resolution within the next decade. Should photon-based lithography still be used for patterning smaller feature sizes, beyond EUV (BEUV) lithography at 6.x nm wavelength is an option that could potentially meet the rigid demands of the semiconductor industry. We demonstrate simultaneous characterization of the resolution, line-edge roughness, and sensitivity of distinct photoresists at BEUV and compare their properties when exposed to EUV under the same conditions. By using interference lithography at these wavelengths, we show the possibility for patterning beyond 22 nm resolution and characterize the impact of using higher energy photons on the line-edge roughness and exposure latitude. We observe high sensitivity of the photoresist performance on its chemical content and compare their overall performance using the Z-parameter criterion. Interestingly, inorganic photoresists have much better performance at BEUV, while organic chemically-amplified photoresists would need serious adaptations for being used at such wavelength. Our results have immediate implications for deeper understanding of the radiation chemistry of novel photoresists at the EUV and soft X-ray spectra.

  11. Wafer scale coating of polymer cantilever fabricated by nanoimprint lithography

    DEFF Research Database (Denmark)

    Greve, Anders; Dohn, Søren; Keller, Stephan Urs

    2010-01-01

    Microcantilevers can be fabricated in TOPAS by nanoimprint lithography, with the dimensions of 500 ¿m length 4.5 ¿m thickness and 100 ¿m width. By using a plasma polymerization technique it is possible to selectively functionalize individually cantilevers with a polymer coating, on wafer scale...

  12. Single etch grating couplers for mass fabrication with DUV lithography

    National Research Council Canada - National Science Library

    Halir, R; Zavargo-Peche, L; Xu, Dan-Xia; Cheben, Pavel; Ma, Rubin; Schmid, Jens Holger; Janz, Siegfried; Densmore, Adam; Ortega-Moñux, A; Molina-Fernández, Í; Fournier, M; Fédeli, J.-M

    2012-01-01

    ... efficiencies with a single etch step, thereby significantly reducing fabrication complexity. Here we demonstrate that such couplers can be fabricated on a large scale with ultra-violet lithography, achieving a 5 dB coupling efficiency at 1,550 nm...

  13. Pattern Definition with DUV-Lithography at DTU Danchip

    DEFF Research Database (Denmark)

    Keil, Matthias; Khomtchenko, Elena; Nyholt, Henrik

    2014-01-01

    or hole comprising patterns -, its symmetry and the separations between the different structures. The projection lithography tool FPA-3000EX4 from Canon (max. NA=0,6; 1:5 reduction) produces patterns on the wafer within a maximum chip area of 22x22mm2 that can be stitched together with an accuracy of 3σ......Deep ultra violet (DUV) illumination generated with the help of a KrF laser can be utilized to produce components having sizes of some hundreds of nanometers. This light source with its 248nm wavelength is exploited in the DUV-lithography equipment at DTU Danchip in order to fill the resolution gap...... between traditional UV-lithography and e-beam lithography. With the help of a DUV stepper, devices with pattern sizes of 250 nm (see in fig. 1) can be produced on a high volume scale, with a throughput of 30 to 90 wafers per hour on 6” or 8” wafers. For R&D purposes also smaller line widths can be printed...

  14. Mix-and-match lithography in a manufacturing environment

    Science.gov (United States)

    Flack, Warren W.; Dameron, David H.; Alameda, Valerie J.; Malek, Ghassan C.

    1992-07-01

    Fabrication of integrated circuits at subhalf micron geometries is currently feasible only using advanced lithography technologies such as direct write e-beam and x-ray systems. These systems are extremely expensive and have low effective throughputs for a production environment. A mix-and-match approach using optical steppers for noncritical levels can dramatically increase productivity and control total lithography costs. A major impact for mix- and-match lithography is the total root mean squared alignment errors between systems. Implementation of a larger overlay budget to accommodate mix-and-match errors adversely impacts design rules for submicron technologies. However, a maskless lithography tool such as direct write e-beam offers the potential to compensate for systematic errors during wafer patterning and dramatically reduce the overlay budget for those layers. At TRW, a mix-and- match scheme has been developed between a Hitachi HL-700D e-beam direct write system and a Ultratech 1500 wide field 1X stepper. A previous analysis using only the linear distortion terms between these systems was found to be inadequate to fully explain the observed overlay. In this study, both linear and higher order distortion components are extracted using a large number of distributed measurement sites in the stepper field. These distortion terms are then analyzed to determine their source. Compensation techniques including both system hardware adjustments and e-beam software are investigated to enhance registration capabilities.

  15. Applications of nanoimprint lithography/hot embossing: a review

    Science.gov (United States)

    Chen, Yifang

    2015-11-01

    This review concentrates on the applications of nanoimprint lithography (NIL) and hot embossing for the fabrications of nanolectronic devices, nanophotonic metamaterials and other nanostructures. Technical challenges and solutions in NIL such as nanofabrication of templates, removal of residual resist, pattern displacement in thermal NIL arising from thermal expansion are first discussed. In the nanofabrication of templates, dry etch in plasma for the formation of multi-step structures and ultra-sharp tip arrays in silicon, nanophotonic chiral structures with high aspect ratio in SiC are demonstrated. A bilayer technique for nondestructive removal of residual resist in thermal NIL is described. This process is successfully applied for the fabrication of T-shape gates and functional high electron mobility transistors. However, pattern displacement intrinsically existing in thermal NIL/hot embossing owing to different thermal expansions in the template and substrate, respectively, limits its further development and scale-up. Low temperature even room temperature NIL (RTNIL) was then proposed on HSQ, trying to eliminate the pattern distortion by avoiding a thermal loop in the imprint. But, considerable pressure needed in RTNIL turned the major attentions to the development of UV-curing NIL in UV-curable monomers at low temperature. A big variety of applications by low-temperature UV-curing NIL in SU-8 are described, including high-aspect-ratio phase gratings, tagging technology by nanobarcode for DNA sequencing, nanofluidic channels, nanophotonic metamaterials and biosensors. Hot embossing, as a parallel technique to NIL, was also developed, and its applications on ferroelectric polymers as well as metals are reviewed. Therefore, it is necessary to emphasize that this review is mainly attempted to review the applications of NIL/embossing instead of NIL technique advances.

  16. Zero expansion glass ceramic ZERODUR® roadmap for advanced lithography

    Science.gov (United States)

    Westerhoff, Thomas; Jedamzik, Ralf; Hartmann, Peter

    2013-04-01

    The zero expansion glass ceramic ZERODUR® is a well-established material in microlithography in critical components as wafer- and reticle-stages, mirrors and frames in the stepper positioning and alignment system. The very low coefficient of thermal expansion (CTE) and its extremely high CTE homogeneity are key properties to achieve the tight overlay requirements of advanced lithography processes. SCHOTT is continuously improving critical material properties of ZERODUR® essential for microlithography applications according to a roadmap driven by the ever tighter material specifications broken down from the customer roadmaps. This paper will present the SCHOTT Roadmap for ZERODUR® material property development. In the recent years SCHOTT established a physical model based on structural relaxation to describe the coefficient of thermal expansion's temperature dependence. The model is successfully applied for the new expansion grade ZERODUR® TAILORED introduced to the market in 2012. ZERODUR® TAILORED delivers the lowest thermal expansion of ZERODUR® products at microlithography tool application temperature allowing for higher thermal stability for tighter overlay control in IC production. Data will be reported demonstrating the unique CTE homogeneity of ZERODUR® and its very high reproducibility, a necessary precondition for serial production for microlithography equipment components. New data on the bending strength of ZERODUR® proves its capability to withstand much higher mechanical loads than previously reported. Utilizing a three parameter Weibull distribution it is possible to derive minimum strength values for a given ZERODUR® surface treatment. Consequently the statistical uncertainties of the earlier approach based on a two parameter Weibull distribution have been eliminated. Mechanical fatigue due to stress corrosion was included in a straightforward way. The derived formulae allows calculating life time of ZERODUR® components for a given stress

  17. Stop Flow Lithography Synthesis and Characterization of Structured Microparticles

    Directory of Open Access Journals (Sweden)

    David Baah

    2014-01-01

    Full Text Available In this study, the synthesis of nonspherical composite particles of poly(ethylene glycol diacrylate (PEG-DA/SiO2 and PEG-DA/Al2O3 with single or multiple vias and the corresponding inorganic particles of SiO2 and Al2O3 synthesized using the Stop Flow Lithography (SFL method is reported. Precursor suspensions of PEG-DA, 2-hydroxy-2-methylpropiophenone, and SiO2 or Al2O3 nanoparticles were prepared. The precursor suspension flows through a microfluidic device mounted on an upright microscope and is polymerized in an automated process. A patterned photomask with transparent geometric features masks UV light to synthesize the particles. Composite particles with vias were synthesized and corresponding inorganic SiO2 and Al2O3 particles were obtained through polymer burn-off and sintering of the composites. The synthesis of porous inorganic particles of SiO2 and Al2O3 with vias and overall dimensions in the range of ~35–90 µm was achieved. BET specific surface area measurements for single via inorganic particles were 56–69 m2/g for SiO2 particles and 73–81 m2/g for Al2O3 particles. Surface areas as high as 114 m2/g were measured for multivia cubic SiO2 particles. The findings suggest that, with optimization, the particles should have applications in areas where high surface area is important such as catalysis and sieving.

  18. Large-scale electrohydrodynamic organic nanowire printing, lithography, and electronics

    Science.gov (United States)

    Lee, Tae-Woo

    2014-03-01

    Although the many merits of organic nanowires (NWs), a reliable process for controllable and large-scale assembly of highly-aligned NW parallel arrays based on ``individual control (IC)'' of NWs must be developed since inorganic NWs are mainly grown vertically on substrates and thus have been transferred to the target substrates by any of several non-individually controlled (non-IC) methods such as contact-printing technologies with unidirectional massive alignment, and the random dispersion method with disordered alignment. Controlled alignment and patterning of individual semiconducting NWs at a desired position in a large area is a major requirement for practical electronic device applications. Large-area, high-speed printing of highly-aligned individual NWs that allows control of the exact numbers of wires, and dimensions and their orientations, and its use in high-speed large-area nanolithography is a significant challenge for practical applications. Here we use a high-speed electrohydrodynamic organic nanowire printer to print large-area organic semiconducting nanowire arrays directly on device substrates in an accurately individually-controlled manner; this method also enables sophisticated large-area nanowire lithography for nano-electronics. We achieve an unprecedented high maximum field-effect mobility up to 9.7 cm2 .V-1 .s-1 with extremely low contact resistance (<5.53 Ω . cm) even in nano-channel transistors based on single-stranded semiconducting NWs. We also demonstrate complementary inverter circuit arrays consist of well-aligned p-type and n-type organic semiconducting NWs. Extremely fast nanolithography using printed semiconducting nanowire arrays provide a very simple, reliable method of fabricating large-area and flexible nano-electronics.

  19. Plasma etch challenges with new EUV lithography material introduction for patterning for MOL and BEOL

    Science.gov (United States)

    Lee, Changwoo; Nagabhirava, Bhaskar; Goss, Michael; Wang, Peng; Friddle, Phil; Schmitz, Stafan; Wu, Jian; Yang, Richard; Mignot, Yann; Rassoul, Nouradine; Hamieh, Bassem; Beique, Genevieve; Labonte, Andre; Labelle, Catherine; Arnold, John; Mucci, John

    2015-03-01

    As feature critical dimension (CD) shrinks towards and beyond the 7nm node, patterning techniques for optical lithography with double and triple exposure will be replaced by EUV patterning. EUV enables process and overlay improvement, as well as a potential cost reduction due to fewer wafer passes and masks required for patterning. However, the EUV lithography technique introduces newer types of resists that are thinner and softer compared to conventional 193nm resists currently being used. The main challenge is to find the key etch process parameters to improve the EUV resist selectivity, reduce LER and LWR, minimize line end shrink, improve tip-to-tip degradation, and avoid line wiggling while still enabling previous schemes such as trench-first-metal-hard-mask (TFMHM), self-aligned via (SAV) and self-aligned contact (SAC). In this paper, we will discuss some of the approaches that we have investigated to define the best etch process adjustments to enable EUV patterning. RF pulsing is one of the key parameters utilized to overcome most of the previously described challenges, and has also been coupled with stack optimization. This study will focus on RF pulsing (high vs. low frequency results) and bias control (RF frequency dependence). In particular, pulsing effects on resist morphology, selectivity and profile management will be reported, as well as the role of aspect ratio and etch chemistry on organic mask wiggling and collapse. This work was performed by the Research Alliance Teams at various IBM Research and Development Facilities.

  20. Ion beam etching of multilevel masking layers written by two-photon lithography

    Science.gov (United States)

    Schmitt, Jana; Hengsbach, Stefan; Bade, Klaus; Wallrabe, Ulrike; Völklein, Friedemann

    2017-07-01

    Ion beam etching (IBE) provides high surface quality. Finding suitable masking layers is one of the key issues for process optimization. In case of high-intensity and long-term IBE conventional photoresists are not appropriate as masking layers. As an alternative in terms of thermal durability, photoresist masking layers polymerized with two-photon lithography were investigated here and their IBE etch rates were measured. A hard bake (200 °C) lowered them due to higher crosslinking without an alteration of the structure shapes. Two-photon lithography enables the fabrication of multilevel structures which can be etched in one process step. Two types of 3D masking layers were transferred into fused silica to demonstrate this approach. Diffractive structures were chosen because their diffraction efficiency benefits from the high surface quality provided by IBE and it is influenced by fabrication induced deviations of the geometry: 3D line gratings with overlapping photoresist areas are a new approach to avoid delamination problems without the necessity of the integration of unwanted gaps into the resist patterns. Measurements proved good agreement of the diffraction efficiency with simulated results, differ only by 1.14%. The transfer of blazed grating structures illustrated the effect of the angle dependence of the etch rate. The transferred structures showed good agreement with the step heights forecast on the basis of process selectivity.

  1. Via patterning in the 7-nm node using immersion lithography and graphoepitaxy directed self-assembly

    Science.gov (United States)

    Doise, Jan; Bekaert, Joost; Chan, Boon Teik; Hori, Masafumi; Gronheid, Roel

    2017-04-01

    Insertion of a graphoepitaxy directed self-assembly process as a via patterning technology into integrated circuit fabrication is seriously considered for the 7-nm node and beyond. At these dimensions, a graphoepitaxy process using a cylindrical block copolymer that enables hole multiplication can alleviate costs by extending 193-nm immersion-based lithography and significantly reducing the number of masks that would be required per layer. To be considered for implementation, it needs to be proved that this approach can achieve the required pattern quality in terms of defects and variability using a representative, aperiodic design. The patterning of a via layer from an actual 7-nm node logic layout is demonstrated using immersion lithography and graphoepitaxy directed self-assembly in a fab-like environment. The performance of the process is characterized in detail on a full 300-mm wafer scale. The local variability in an edge placement error of the obtained patterns (4.0 nm 3σ for singlets) is in line with the recent results in the field and significantly less than of the prepattern (4.9 nm 3σ for singlets). In addition, it is expected that pattern quality can be further improved through an improved mask design and optical proximity correction. No major complications for insertion of the graphoepitaxy directed self-assembly into device manufacturing were observed.

  2. Rapid prototyping of microstructures in polydimethylsiloxane (PDMS) by direct UV-lithography.

    Science.gov (United States)

    Scharnweber, Tim; Truckenmüller, Roman; Schneider, Andrea M; Welle, Alexander; Reinhardt, Martina; Giselbrecht, Stefan

    2011-04-07

    Microstructuring of polydimethylsiloxane (PDMS) is a key step for many lab-on-a-chip (LOC) applications. In general, the structure is generated by casting the liquid prepolymer against a master. The production of the master in turn calls for special equipment and know how. Furthermore, a given master only allows the reproduction of the defined structure. We report on a simple, cheap and practical method to produce microstructures in already cured PDMS by direct UV-lithography followed by chemical development. Due to the available options during the lithographic process like multiple exposures, the method offers a high design flexibility granting easy access to complex and stepped structures. Furthermore, no master is needed and the use of pre-cured PDMS allows processing at ambient (light) conditions. Features down to approximately 5 µm and a depth of 10 µm can be realised. As a proof of principle, we demonstrate the feasibility of the process by applying the structures to various established soft lithography techniques.

  3. Advanced lithography simulation for various 3-dimensional nano/microstructuring fabrications in positive- and negative-tone photoresists.

    Science.gov (United States)

    Kim, Sang-Kon; Oh, Hye-Keun; Jung, Young-Dae; An, Ilsin

    2011-01-01

    Photoresist lithography has been applied to the fabrication of micro/nano devices, such as microfluidic structures, quantum dots, and photonic devices, in MEMS (micro-electro mechanical systems) and NEMS (nano-electro-mechanical systems). In particular, nano devices can be expected to present different physical phenomena due to their three-dimensional (3D) structure. The flexible 3D micro/nano fabrication technique and its process simulation have become among the major topics needed to understand nano-mechanical phenomena. For this purpose, the moving-mask technology and the lithography processes for the positive- and negative-tone photoresists were modeled. The validity of the simulation of the proposed 3D nano/microstructuring was successfully confirmed by comparing the experiment results and the simulated results. Hence, the developed model and the simulation can present and optimize photoresist characteristics and lithography process conditions due to the various 3D nano/microstructures. They could be help in the understanding of nanomaterial and mechanical phenomena.

  4. Modulating two-dimensional non-close-packed colloidal crystal arrays by deformable soft lithography.

    Science.gov (United States)

    Li, Xiao; Wang, Tieqiang; Zhang, Junhu; Yan, Xin; Zhang, Xuemin; Zhu, Difu; Li, Wei; Zhang, Xun; Yang, Bai

    2010-02-16

    We report a simple method to fabricate two-dimensional (2D) periodic non-close-packed (ncp) arrays of colloidal microspheres with controllable lattice spacing, lattice structure, and pattern arrangement. This method combines soft lithography technique with controlled deformation of polydimethylsiloxane (PDMS) elastomer to convert 2D hexagonal close-packed (hcp) silica microsphere arrays into ncp ones. Self-assembled 2D hcp microsphere arrays were transferred onto the surface of PDMS stamps using the lift-up technique, and then their lattice spacing and lattice structure could be adjusted by solvent swelling or mechanical stretching of the PDMS stamps. Followed by a modified microcontact printing (microcp) technique, the as-prepared 2D ncp microsphere arrays were transferred onto a flat substrate coated with a thin film of poly(vinyl alcohol) (PVA). After removing the PVA film by calcination, the ncp arrays that fell on the substrate without being disturbed could be lifted up, deformed, and transferred again by another PDMS stamp; therefore, the lattice feature could be changed step by step. Combining isotropic solvent swelling and anisotropic mechanical stretching, it is possible to change hcp colloidal arrays into full dimensional ncp ones in all five 2D Bravais lattices. This deformable soft lithography-based lift-up process can also generate patterned ncp arrays of colloidal crystals, including one-dimensional (1D) microsphere arrays with designed structures. This method affords opportunities and spaces for fabrication of novel and complex structures of 1D and 2D ncp colloidal crystal arrays, and these as-prepared structures can be used as molds for colloidal lithography or prototype models for optical materials.

  5. Design and fabrication of Si-based photonic crystal stamps with electron beam lithography (EBL)

    Science.gov (United States)

    Jannesary, Reyhaneh; Bergmair, Iris; Zamiri, Saeid; Hingerl, Kurt; Hubbard, Graham; Abbott, Steven; Chen, Qin; Allsopp, Duncan

    2009-05-01

    The quest for mass replication has established technologies like nanoimprinting via hard stamps or PDMS stamps, where the stamps are usually produced via Electron Beam Lithography (EBL) for applications in the microelectronic industry. On the other hand, nanopatterning with self ordered structures1 or via holographic patterns provide the basis for large area imprints for applications for example, antireflection coatings based on biomimetic motheyes2. In this work we report on a technology for enabling the mass replication of custom-designed and e-beam lithographically prepared structures via establishing novel roll to roll nanoimprint processes for pattern transfer into UV curable pre-polymers. The new nano-fabrication technology is based on the concept of Disposal Master Technology (DMT) capable of patterning areas up to 1 x 1 m2 and is suitable for mass volume manufacturing of large area arrays of sub-wavelength photonic elements. As an example to show the potential of the application of the new nanoimprint technologies, we choose the fabrication of a photonic crystal (PhC) structure with integrated light coupling devices for low loss interconnection between PhC lightwave circuits and optical fibre systems. We present two methods for fabrication of nanoimprint lithography stamps in Si substrate. In the first method optimized electron beam lithography (EBL) and lift-off patterning of a 15-nm thick Cr mask, and then the pattern transfer into Si using reacting ion etching (RIE) with SF6 as etch gas. In the first method, we use 200nm of positive resist PMMA 950K for EBL exposure. In this method, resist thickness, exposure dose, development time and parameter for etching have been optimized and a photonic crystal of Si-rods in air was fabricated. In the second method lift-off has not been performed and metal mask has been used as master. The subsequent steps for fabricating the master will be presented in detail.

  6. Cell projection use in maskless lithography for 45nm and 32nm logic nodes

    Science.gov (United States)

    Manakli, S.; Komami, H.; Takizawa, M.; Mitsuhashi, T.; Pain, L.

    2009-03-01

    Due to the ever-increasing cost of equipment and mask complexity, the use of optical lithography for integrated circuit manufacturing is increasingly more complex and expensive. Recent workshops and conferences in semiconductor lithography underlined that one alternative to support sub-32nm technologies is mask-less lithography option using electron beam technology. However, this direct write approach based on variable shaped beam principle (VSB) is not sufficient in terms of throughput, i.e. of productivity. New direct write techniques like multibeam systems are under development, but these solutions will not be mature before 2012. The use of character/cell projection (CP) on industrial VSB tools is the first step to deal with the throughput concerns. This paper presents the status of the CP technology and evaluates its possible use for the 45nm and 32nm logic nodes. It will present standard cell and SRAM structures that are printed as single characters using the CP technique. All experiments are done using the Advantest tool (F3000) which can project up to 100 different cells per layer. Cell extractions and design have been performed with the design and software solution developed by D2S. In this paper, we first evaluate the performance gain that can be obtained with the CP approach compared to the standard VSB approach. This paper also details the patterning capability obtained by using the CP concept. An evaluation of the CD uniformity and process stability is also presented. Finally this paper discusses about the improvements of this technique to address high resolution and to improve the throughput concerns.

  7. Protein assay structured on paper by using lithography

    Science.gov (United States)

    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.

  8. Extreme ultraviolet lithography mask etch study and overview

    Science.gov (United States)

    Wu, Banqiu; Kumar, Ajay; Chandrachood, Madhavi; Sabharwal, Amitabh

    2013-04-01

    An overview of extreme ultraviolet lithography (EUVL) mask etch is presented and a EUVL mask etch study was carried out. Today, EUVL implementation has three critical challenges that hinder its adoption: extreme ultraviolet (EUV) source power, resist resolution-line width roughness-sensitivity, and a qualified EUVL mask. The EUVL mask defect challenges result from defects generated during blank preparation, absorber and multilayer deposition processes, as well as patterning, etching and wet clean processes. Stringent control on several performance criteria including critical dimension (CD) uniformity, etch bias, micro-loading, profile control, defect control, and high etch selectivity requirement to capping layer is required during the resist pattern duplication on the underlying absorber layer. EUVL mask absorbers comprise of mainly tantalum-based materials rather than chrome- or MoSi-based materials used in standard optical masks. Compared to the conventional chrome-based absorbers and phase shift materials, tantalum-based absorbers need high ion energy to obtain moderate etch rates. However, high ion energy may lower resist selectivity, and could introduce defects. Current EUVL mask consists of an anti-reflective layer on top of the bulk absorber. Recent studies indicate that a native oxide layer would suffice as an anti-reflective coating layer during the electron beam inspection. The absorber thickness and the material properties are optimized based on optical density targets for the mask as well as electromagnetic field effects and optics requirements of the patterning tools. EUVL mask etch processes are modified according to the structure of the absorber, its material, and thickness. However, etch product volatility is the fundamental requirement. Overlapping lithographic exposure near chip border may require etching through the multilayer, resulting in challenges in profile control and etch selectivity. Optical proximity correction is applied to further

  9. Hybrid inverse lithography techniques for advanced hierarchical memories

    Science.gov (United States)

    Xiao, Guangming; Hooker, Kevin; Irby, Dave; Zhang, Yunqiang; Ward, Brian; Cecil, Tom; Hall, Brett; Lee, Mindy; Kim, Dave; Lucas, Kevin

    2014-03-01

    Traditional segment-based model-based OPC methods have been the mainstream mask layout optimization techniques in volume production for memory and embedded memory devices for many device generations. These techniques have been continually optimized over time to meet the ever increasing difficulties of memory and memory periphery patterning. There are a range of difficult issues for patterning embedded memories successfully. These difficulties include the need for a very high level of symmetry and consistency (both within memory cells themselves and between cells) due to circuit effects such as noise margin requirements in SRAMs. Memory cells and access structures consume a large percentage of area in embedded devices so there is a very high return from shrinking the cell area as much as possible. This aggressive scaling leads to very difficult resolution, 2D CD control and process window requirements. Additionally, the range of interactions between mask synthesis corrections of neighboring areas can extend well beyond the size of the memory cell, making it difficult to fully take advantage of the inherent designed cell hierarchy in mask pattern optimization. This is especially true for non-traditional (i.e., less dependent on geometric rule) OPC/RET methods such as inverse lithography techniques (ILT) which inherently have more model-based decisions in their optimizations. New inverse methods such as model-based SRAF placement and ILT are, however, well known to have considerable benefits in finding flexible mask pattern solutions to improve process window, improve 2D CD control, and improve resolution in ultra-dense memory patterns. They also are known to reduce recipe complexity and provide native MRC compliant mask pattern solutions. Unfortunately, ILT is also known to be several times slower than traditional OPC methods due to the increased computational lithographic optimizations it performs. In this paper, we describe and present results for a methodology to

  10. Microfocussing of synchrotron X-rays using X-ray refractive lens developed at Indus-2 deep X-ray lithography beamline

    Indian Academy of Sciences (India)

    V P Dhamgaye; M K Tiwari; K J S Sawhney; G S Lodha

    2014-07-01

    X-ray lenses are fabricated in polymethyl methacrylate using deep X-ray lithography beamline of Indus-2. The focussing performance of these lenses is evaluated using Indus-2 and Diamond Light Source Ltd. The process steps for the fabrication of X-ray lenses and microfocussing at 10 keV at moderate and low emittance sources are compared.

  11. Reduction of nanowire diameter beyond lithography limits by controlled catalyst dewetting

    Science.gov (United States)

    Calahorra, Yonatan; Kerlich, Alexander; Amram, Dor; Gavrilov, Arkady; Cohen, Shimon; Ritter, Dan

    2016-04-01

    Catalyst assisted vapour-liquid-solid is the most common method to realize bottom-up nanowire growth; establishing a parallel process for obtaining nanoscale catalysts at pre-defined locations is paramount for further advancement towards commercial nanowire applications. Herein, the effect of a selective area mask on the dewetting of metallic nanowire catalysts, deposited within lithography-defined mask pinholes, is reported. It was found that thin disc-like catalysts, with diameters of 120-450 nm, were transformed through dewetting into hemisphere-like catalysts, having diameters 2-3 fold smaller; the process was optimized to about 95% yield in preventing catalyst splitting, as would otherwise be expected due to their thickness-to-diameter ratio, which was as low as 1/60. The catalysts subsequently facilitated InP and InAs nanowire growth. We suggest that the mask edges prevent surface migration mediated spreading of the dewetted metal, and therefore induce its agglomeration into a single particle. This result presents a general strategy to diminish lithography-set dimensions for NW growth, and may answer a fundamental challenge faced by bottom-up nanowire technology.

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

    Science.gov (United States)

    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.

  13. Self-assembly and nanosphere lithography for large-area plasmonic patterns on graphene.

    Science.gov (United States)

    Lotito, Valeria; Zambelli, Tomaso

    2015-06-01

    Plasmonic structures on graphene can tailor its optical properties, which is essential for sensing and optoelectronic applications, e.g. for the enhancement of photoresponsivity of graphene photodetectors. Control over their structural and, hence, spectral properties can be attained by using electron beam lithography, which is not a viable solution for the definition of patterns over large areas. For the fabrication of large-area plasmonic nanostructures, we propose to use self-assembled monolayers of nanospheres as a mask for metal evaporation and etching processes. An optimized approach based on self-assembly at air/water interface with a properly designed apparatus allows the attainment of monolayers of hexagonally closely packed patterns with high long-range order and large area coverage; special strategies are devised in order to protect graphene against damage resulting from surface treatment and further processing steps such as reactive ion etching, which could potentially impair graphene properties. Therefore we demonstrate that nanosphere lithography is a cost-effective solution to create plasmonic patterns on graphene. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Fabrication of Silicon Nanobelts and Nanopillars by Soft Lithography for Hydrophobic and Hydrophilic Photonic Surfaces.

    Science.gov (United States)

    Baquedano, Estela; Martinez, Ramses V; Llorens, José M; Postigo, Pablo A

    2017-05-11

    Soft lithography allows for the simple and low-cost fabrication of nanopatterns with different shapes and sizes over large areas. However, the resolution and the aspect ratio of the nanostructures fabricated by soft lithography are limited by the depth and the physical properties of the stamp. In this work, silicon nanobelts and nanostructures were achieved by combining soft nanolithography patterning with optimized reactive ion etching (RIE) in silicon. Using polymethylmethacrylate (PMMA) nanopatterned layers with thicknesses ranging between 14 and 50 nm, we obtained silicon nanobelts in areas of square centimeters with aspect ratios up to ~1.6 and linewidths of 225 nm. The soft lithographic process was assisted by a thin film of SiOx (less than 15 nm) used as a hard mask and RIE. This simple patterning method was also used to fabricate 2D nanostructures (nanopillars) with aspect ratios of ~2.7 and diameters of ~200 nm. We demonstrate that large areas patterned with silicon nanobelts exhibit a high reflectivity peak in the ultraviolet C (UVC) spectral region (280 nm) where some aminoacids and peptides have a strong absorption. We also demonstrated how to tailor the aspect ratio and the wettability of these photonic surfaces (contact angles ranging from 8.1 to 96.2°) by changing the RIE power applied during the fabrication process.

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

    Science.gov (United States)

    Iberi, Vighter; Vlassiouk, Ivan; Zhang, X.-G.; Matola, Brad; Linn, Allison; Joy, David C.; Rondinone, Adam J.

    2015-01-01

    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 ion 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. PMID:26150202

  16. Fabrication of superconducting NbN meander nanowires by nano-imprint lithography

    Science.gov (United States)

    Mei, Yang; Li-Hua, Liu; Lu-Hui, Ning; Yi-Rong, Jin; Hui, Deng; Jie, Li; Yang, Li; Dong-Ning, Zheng

    2016-01-01

    Superconducting nanowire single photon detector (SNSPD), as a new type of superconducting single photon detector (SPD), has a broad application prospect in quantum communication and other fields. In order to prepare SNSPD with high performance, it is necessary to fabricate a large area of uniform meander nanowires, which is the core of the SNSPD. In this paper, we demonstrate a process of patterning ultra-thin NbN films into meander-type nanowires by using the nano-imprint technology. In this process, a combination of hot embossing nano-imprint lithography (HE-NIL) and ultraviolet nano-imprint lithography (UV-NIL) is used to transfer the meander nanowire structure from the NIL Si hard mold to the NbN film. We have successfully obtained a NbN nanowire device with uniform line width. The critical temperature (Tc) of the superconducting NbN meander nanowires is about 5 K and the critical current (Ic) is about 3.5 μA at 2.5 K. Project supported by the National Basic Research Program of China (Grant Nos. 2011CBA00106 and 2009CB929102) and the National Natural Science Foundation of China (Grant Nos. 11104333 and 10974243).

  17. Fabrication of superconducting MgB2 nanostructures by an electron beam lithography-based technique

    Science.gov (United States)

    Portesi, C.; Borini, S.; Amato, G.; Monticone, E.

    2006-03-01

    In this work, we present the results obtained in fabrication and characterization of magnesium diboride nanowires realized by an electron beam lithography (EBL)-based method. For fabricating MgB2 thin films, an all in situ technique has been used, based on the coevaporation of B and Mg by means of an e-gun and a resistive heater, respectively. Since the high temperatures required for the fabrication of good quality MgB2 thin films do not allow the nanostructuring approach based on the lift-off technique, we structured the samples combining EBL, optical lithography, and Ar milling. In this way, reproducible nanowires 1 μm long have been obtained. To illustrate the impact of the MgB2 film processing on its superconducting properties, we measured the temperature dependence of the resistance on a nanowire and compared it to the original magnesium diboride film. The electrical properties of the films are not degraded as a consequence of the nanostructuring process, so that superconducting nanodevices may be obtained by this method.

  18. Simulation study of the NA/σ's dependence of DOF for 193-nm immersion lithography at 65-nm node

    Institute of Scientific and Technical Information of China (English)

    Guosheng Huang; Yanqiu Li

    2005-01-01

    @@ Recently, ArF immersion lithography has been considered as a promising method after ArF dry lithography by a factor of refractive index n of the liquid filled into the space between the bottom lens and wafer,in the case of 193-nm exposure tools, water (n = 1.44) has been found as the best liquid. We explore the NA/σ's dependence of depth of focus (DOF) under 3/4 annular and 3/4 quasar illumination by resist Finally, we explored the high NA's dependency of DOF and gave the explanation for the peak value of DOF through three-beam imaging process, MicroCruiser 2.0, Prolith version 8.0.2 and k2 factor based on the Rayleigh equation.

  19. Selective binding of oligonucleotide on TiO{sub 2} surfaces modified by swift heavy ion beam lithography

    Energy Technology Data Exchange (ETDEWEB)

    Vicente Pérez-Girón, J. [Nanoate, S.L. C/Poeta Rafael Morales 2, San Sebastian de los Reyes, 28702 Madrid (Spain); Emerging Viruses Department Heinrich Pette Institute, Hamburg 20251 (Germany); Hirtz, M. [Institute of Nanotechnology (INT) and Karlsruhe Nano Micro Facility (KNMF), Karlsruhe Institute of Technology - KIT, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); McAtamney, C.; Bell, A.P. [Advanced Microscopy Laboratory, CRANN, Trinity College Dublin, Dublin 2 (Ireland); Antonio Mas, J. [Laboratorio de Genómica del Centro de Apoyo Tecnológico, Universidad Rey Juan Carlos, Campus de Alcorcón 28922, Madrid (Spain); Jaafar, M. [Nanoate, S.L. C/Poeta Rafael Morales 2, San Sebastian de los Reyes, 28702 Madrid (Spain); Departamento de Física de la Materia Condensada, Facultad de Ciencias, Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049 Madrid (Spain); Luis, O. de [Nanoate, S.L. C/Poeta Rafael Morales 2, San Sebastian de los Reyes, 28702 Madrid (Spain); Departamento de Bioquímica, Fisiología y Genética Molecular, Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Campus de Alcorcón, 28922 Madrid (Spain); Fuchs, H. [Institute of Nanotechnology (INT) and Karlsruhe Nano Micro Facility (KNMF), Karlsruhe Institute of Technology - KIT, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Physical Institute and Center for Nanotechnology (CeNTech), Wilhelm-Klemm-Straße 10, University of Münster (Germany); and others

    2014-11-15

    We have used swift heavy-ion beam based lithography to create patterned bio-functional surfaces on rutile TiO{sub 2} single crystals. The applied lithography method generates a permanent and well defined periodic structure of micrometre sized square holes having nanostructured TiO{sub 2} surfaces, presenting different physical and chemical properties compared to the surrounding rutile single crystal surface. On the patterned substrates selective binding of oligonucleotides molecules is possible at the surfaces of the holes. This immobilisation process is only being controlled by UV light exposure. The patterned transparent substrates are compatible with fluorescence detection techniques, are mechanically robust, have a high tolerance to extreme chemical and temperature environments, and apparently do not degrade after ten cycles of use. These qualities make the patterned TiO{sub 2} substrates useful for potential biosensor applications.

  20. Quantum repeated games revisited

    CERN Document Server

    Frackiewicz, Piotr

    2011-01-01

    We present a scheme for playing quantum repeated 2x2 games based on the Marinatto and Weber's approach to quantum games. As a potential application, we study twice repeated Prisoner's Dilemma game. We show that results not available in classical game can be obtained when the game is played in the quantum way. Before we present our idea, we comment on the previous scheme of playing quantum repeated games.

  1. Programmable lithography engine (ProLE) grid-type supercomputer and its applications

    Science.gov (United States)

    Petersen, John S.; Maslow, Mark J.; Gerold, David J.; Greenway, Robert T.

    2003-06-01

    There are many variables that can affect lithographic dependent device yield. Because of this, it is not enough to make optical proximity corrections (OPC) based on the mask type, wavelength, lens, illumination-type and coherence. Resist chemistry and physics along with substrate, exposure, and all post-exposure processing must be considered too. Only a holistic approach to finding imaging solutions will accelerate yield and maximize performance. Since experiments are too costly in both time and money, accomplishing this takes massive amounts of accurate simulation capability. Our solution is to create a workbench that has a set of advanced user applications that utilize best-in-class simulator engines for solving litho-related DFM problems using distributive computing. Our product, ProLE (Programmable Lithography Engine), is an integrated system that combines Petersen Advanced Lithography Inc."s (PAL"s) proprietary applications and cluster management software wrapped around commercial software engines, along with optional commercial hardware and software. It uses the most rigorous lithography simulation engines to solve deep sub-wavelength imaging problems accurately and at speeds that are several orders of magnitude faster than current methods. Specifically, ProLE uses full vector thin-mask aerial image models or when needed, full across source 3D electromagnetic field simulation to make accurate aerial image predictions along with calibrated resist models;. The ProLE workstation from Petersen Advanced Lithography, Inc., is the first commercial product that makes it possible to do these intensive calculations at a fraction of a time previously available thus significantly reducing time to market for advance technology devices. In this work, ProLE is introduced, through model comparison to show why vector imaging and rigorous resist models work better than other less rigorous models, then some applications of that use our distributive computing solution are shown

  2. On the similarities between micro/nano lithography and topology optimization projection methods

    DEFF Research Database (Denmark)

    Jansen, Miche; Lazarov, Boyan Stefanov; Schevenels, Mattias;

    2013-01-01

    The aim of this paper is to incorporate a model for micro/nano lithography production processes in topology optimization. The production process turns out to provide a physical analogy for projection filters in topology optimization. Blueprints supplied by the designers cannot be directly used...... projection filter can be used to account for uncertainties due to lithographic production processes which results in manufacturable blueprint designs and eliminates the need for subsequent corrections....... as inputs to lithographic processes due to the proximity effect which causes rounding of sharp corners and geometric interaction of closely spaced design elements. Therefore, topology optimization is applied as a tool for proximity effect correction. Furthermore, it is demonstrated that the robust...

  3. Multilayer, Stacked Spiral Copper Inductors on Silicon with Micro-Henry Inductance Using Single-Level Lithography

    Directory of Open Access Journals (Sweden)

    Timothy Reissman

    2012-01-01

    Full Text Available We present copper structures composed of multilayer, stacked inductors (MLSIs with tens of micro-Henry inductance for use in low frequency (sub 100 MHz, power converter technology. Unique to this work is the introduction of single-level lithography over the traditional two-level approach to create each inductor layer. The result is a simplified fabrication process which results in a reduction in the number of lithography steps per inductor (metal layer and a reduction in the necessary alignment precision. Additionally, we show that this fabrication process yields strong adhesion amongst the layers, since even after a postprocess abrasion technique at the inner diameter of the inductors, no shearing occurs and connectivity is preserved. In total, three separate structures were fabricated using the single-level lithography approach, each with a three-layered, stacked inductor design but with varied geometries. Measured values for each of the structures were extracted, and the following results were obtained: inductance values of 24.74, 17.25, and 24.74 μH, self-resonances of 9.87, 5.72, and 10.58 MHz, and peak quality factors of 2.26, 2.05, and 4.6, respectively. These values are in good agreement with the lumped parameter model presented.

  4. Molecular Switch for Sub-Diffraction Laser Lithography by Photoenol Intermediate-State Cis-Trans Isomerization.

    Science.gov (United States)

    Mueller, Patrick; Zieger, Markus M; Richter, Benjamin; Quick, Alexander S; Fischer, Joachim; Mueller, Jonathan B; Zhou, Lu; Nienhaus, Gerd Ulrich; Bastmeyer, Martin; Barner-Kowollik, Christopher; Wegener, Martin

    2017-06-27

    Recent developments in stimulated-emission depletion (STED) microscopy have led to a step change in the achievable resolution and allowed breaking the diffraction limit by large factors. The core principle is based on a reversible molecular switch, allowing for light-triggered activation and deactivation in combination with a laser focus that incorporates a point or line of zero intensity. In the past years, the concept has been transferred from microscopy to maskless laser lithography, namely direct laser writing (DLW), in order to overcome the diffraction limit for optical lithography. Herein, we propose and experimentally introduce a system that realizes such a molecular switch for lithography. Specifically, the population of intermediate-state photoenol isomers of α-methyl benzaldehydes generated by two-photon absorption at 700 nm fundamental wavelength can be reversibly depleted by simultaneous irradiation at 440 nm, suppressing the subsequent Diels-Alder cycloaddition reaction which constitutes the chemical core of the writing process. We demonstrate the potential of the proposed mechanism for STED-inspired DLW by covalently functionalizing the surface of glass substrates via the photoenol-driven STED-inspired process exploiting reversible photoenol activation with a polymerization initiator. Subsequently, macromolecules are grown from the functionalized areas and the spatially coded glass slides are characterized by atomic-force microscopy. Our approach allows lines with a full-width-at-half-maximum of down to 60 nm and line gratings with a lateral resolution of 100 nm to be written, both surpassing the diffraction limit.

  5. Nanostructured organic solar cells defined by nanoimprint lithography

    Science.gov (United States)

    Aryal, Mukti Nath

    Energy harvesting from sunlight via organic solar cells (OSCs) based on polymers as an electron donors and fullerenes as electron acceptors has been subject of intensive research due to the potential for low cost and large area devices with attractive market perspectives. One of the biggest challenges for OSCs is their low efficiency of power conversion, which is limited by quality of active layer morphology of donor-acceptor materials and interfaces between the components. Key reasons for this low efficiency include severe electron-hole recombination, which prevents charge pair propagation toward the electrodes and poor light absorptions due to thin polymer layer (˜100 nm). These problems can be dramatically alleviated if the charge-transfer polymers can be arranged as periodic nanostructures for active layer of ˜300 nm so that enough light absorption takes place and no phase overlap exists in the charge propagation path. This work reports the formation of ordered bi-continuous interdigitized active layer morphology, well defined interfaces for charge pair formation and propagation without recombination toward the electrodes. Such nanostructure arrays of poly(3-hexylthiophene) (P3HT) with well defined interfaces have been fabricated using nanoimprint lithography (NIL). The molds required for NIL are fabricated using innovative low cost and non-lithographic technique which is scalable to commercial use. Simultaneous control of nanostructured and 3-D chain alignment in P3HT nanostructures (nanowires and nanopillars) defined by NIL is revealed using out-of-plane and in-plane grazing incident X-ray diffraction measurements and enhancement in anisotropic charge carrier mobility favorable to solar cells and field effect transistors (FETs) is measured making FETs. Separate acceptor deposition is required for nanostructured solar cells which is challenging due to the limitation of solvent compatibility and self shadowing effect for thermal deposition. For this purpose

  6. 7nm logic optical lithography with OPC-Lite

    Science.gov (United States)

    Smayling, Michael C.; Tsujita, Koichiro; Yaegashi, Hidetami; Axelrad, Valery; Nakayama, Ryo; Oyama, Kenichi; Yamauchi, Shohei; Ishii, Hiroyuki; Mikami, Koji

    2015-03-01

    The CMOS logic 22nm node was the last one done with single patterning. It used a highly regular layout style with Gridded Design Rules (GDR). Smaller nodes have required the same regular layout style but with multiple patterning for critical layers. A "line/cut" approach is being used to achieve good pattern fidelity and process margin.[1] As shown in Fig. 1, even with "line" patterns, pitch division will eventually be necessary. For the "cut" pattern, Design-Source-Mask Optimization (DSMO) has been demonstrated to be effective at the 20nm node and below.[2,3,4] Single patterning was found to be suitable down to 16nm, while double patterning extended optical lithography for cuts to the 10-12nm nodes. Design optimization avoided the need for triple patterning. Lines can be patterned with 193nm immersion with no complex OPC. The final line dimensions can be achieved by applying pitch division by two or four.[5] In this study, we extend the scaling using simplified OPC to the 7nm node for critical FEOL and BEOL layers. The test block is a reasonably complex logic function with ~100k gates of combinatorial logic and flip-flops, scaled from previous experiments. Simulation results show that for cuts at 7nm logic dimensions, the gate layer can be done with single patterning whose minimum pitch is 53nm, possibly some of the 1x metal layers can be done with double patterning whose minimum pitch is 53nm, and the contact layer will require triple patterning whose minimum pitch is 68nm. These pitches are less than the resolution limit of ArF NA=1.35 (72nm). However these patterns can be separated by a combination of innovative SMO for less than optical resolution limit and a process trick of hole-repair technique. An example of triple patterning coloring is shown in Fig 3. Fin and local interconnect are created by lines and trims. The number of trim patterns are 3 times (min. pitch=90nm) and twice (min. pitch=120nm), respectively. The small number of masks, large pitches, and

  7. High resolution 100 kV electron beam lithography in SU-8

    DEFF Research Database (Denmark)

    Olsen, Brian Bilenberg; Jakobsen, S.; Schmidt, M.S.

    2006-01-01

    High resolution 100 kV electron beam lithography in thin layers of the negative resist SU-8 is demonstrated. Sub-30 nm lines with a pitch down to 300 nm are written in 100 nm thick SU-8. Two reactive ion etch processes are developed in order to transfer the SU-8 structures into a silicon substrate......, a Soft O-2-Plasma process to remove SU-8 residues on the silicon surface after development and a highly anisotropic SF6/O-2/CHF3 based process to transfer the pattern into a silicon substrate, with selectivity between silicon and SU-8 of approximately 2. 30 nm lines patterned in SU-8 are successfully...

  8. Convolution-variation separation method for efficient modeling of optical lithography.

    Science.gov (United States)

    Liu, Shiyuan; Zhou, Xinjiang; Lv, Wen; Xu, Shuang; Wei, Haiqing

    2013-07-01

    We propose a general method called convolution-variation separation (CVS) to enable efficient optical imaging calculations without sacrificing accuracy when simulating images for a wide range of process variations. The CVS method is derived from first principles using a series expansion, which consists of a set of predetermined basis functions weighted by a set of predetermined expansion coefficients. The basis functions are independent of the process variations and thus may be computed and stored in advance, while the expansion coefficients depend only on the process variations. Optical image simulations for defocus and aberration variations with applications in robust inverse lithography technology and lens aberration metrology have demonstrated the main concept of the CVS method.

  9. Electron-beam lithography of gold nanostructures for surface-enhanced Raman scattering

    KAUST Repository

    Yue, Weisheng

    2012-10-26

    The fabrication of nanostructured substrates with precisely controlled geometries and arrangements plays an important role in studies of surface-enhanced Raman scattering (SERS). Here, we present two processes based on electron-beam lithography to fabricate gold nanostructures for SERS. One process involves making use of metal lift-off and the other involves the use of the plasma etching. These two processes allow the successful fabrication of gold nanostructures with various kinds of geometrical shapes and different periodic arrangements. 4-mercaptopyridine (4-MPy) and Rhodamine 6G (R6G) molecules are used to probe SERS signals on the nanostructures. The SERS investigations on the nanostructured substrates demonstrate that the gold nanostructured substrates have resulted in large SERS enhancement, which is highly dependent on the geometrical shapes and arrangements of the gold nanostructures. © 2012 IOP Publishing Ltd.

  10. Ordered silicon microwire arrays grown from substrates patterned using imprint lithography and electrodeposition.

    Science.gov (United States)

    Audesirk, Heather A; Warren, Emily L; Ku, Jessie; Lewis, Nathan S

    2015-01-28

    Silicon microwires grown by the vapor-liquid-solid process have attracted a great deal of interest as potential light absorbers for solar energy conversion. However, the research-scale techniques that have been demonstrated to produce ordered arrays of micro and nanowires may not be optimal for use as high-throughput processes needed for large-scale manufacturing. Herein we demonstrate the use of microimprint lithography to fabricate patterned templates for the confinement of an electrodeposited Cu catalyst for the vapor-liquid-solid (VLS) growth of Si microwires. A reusable polydimethylsiloxane stamp was used to pattern holes in silica sol-gels on silicon substrates, and the Cu catalyst was electrodeposited into the holes. Ordered arrays of crystalline p-type Si microwires were grown across the sol-gel-patterned substrates with materials quality and performance comparable to microwires fabricated with high-purity metal catalysts and cleanroom processing.

  11. Contacting ZnO Individual Crystal Facets by Direct Write Lithography.

    Science.gov (United States)

    Petkov, Nikolay; Volk, János; Erdélyi, Róbert; Lukács, István Endre; Nagata, Takahiro; Sturm, Chris; Grundmann, M

    2016-09-14

    Many advanced electronic devices take advantage of properties developed at the surface facets of grown crystals with submicrometer dimensions. Electrical contacts to individual crystal facets can make possible the investigations of facet-dependent properties such as piezoelectricity in ZnO or III-nitride crystals having noncentrosymmetric structure. However, a lithography-based method for developing contacts to individual crystal facets with submicrometer size has not yet been demonstrated. In this report we study the use of electron beam-induced deposition (EBID), a direct write lithography method, for contacting individual facets of ZnO pillars within an electron microscope. Correlating structural and in situ deposition and electrical data, we examine proximity effects during the EBID and evaluate the process against obtaining electrically insulated contact lines on neighboring and diametrically opposite ZnO facets. Parameters such as incident beam energy geometry and size of the facets were investigated with the view of minimizing unwanted proximity broadening effects. Additionally, we show that the EBID direct write method has the required flexibility, resolution, and minimized proximity deposition for creating prototype devices. The devices were used to observe facet-dependent effects induced by mechanical stress on single ZnO pillar structures.

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

    Science.gov (United States)

    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.

  13. The fabrication of highly ordered silver nanodot patterns by platinum assisted nanoimprint lithography

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Hae-Wook; Jung, Jin-Mi; Lee, Su-kyung; Jung, Hee-Tae, E-mail: heetae@kaist.ac.kr [Department of Chemical and Biomolecular Engineering (BK-21), Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of)

    2011-03-04

    Silver has been widely used for optical sensing and imaging applications which benefit from localized surface plasmon resonance (LSPR) in a nanoscale configuration. Many attempts have been made to fabricate and control silver nanostructures in order to improve the high performance in sensing and other applications. However, a fatal mechanical weakness of silver and a lack of durability in oxygen-rich conditions have disrupted the manufacturing of reproducible nanostructures by the top-down lithography approach. In this study, we suggest a steady fabrication strategy to obtain highly ordered silver nanopatterns that are able to provide tunable LSPR characteristics. By using a protecting layer of platinum on a silver surface in the lithography process, we successfully obtained large-area (2.7 x 2.7 mm{sup 2}) silver nanopatterns with high reproducibility. This large-area silver nanopattern was capable of enhancing the low concentration of a Cy3 fluorescence signal ({approx}10{sup -10} M) which was labeled with DNA oligomers.

  14. Nanoimprint lithography using TiO2-SiO2 ultraviolet curable materials

    Science.gov (United States)

    Takei, Satoshi

    2015-05-01

    Ultraviolet nanoimprint lithography has great potential for commercial device applications that are closest to production such as optical gratings, planar waveguides, photonic crystals, semiconductor, displays, solar cell panel, sensors, highbrightness LEDs, OLEDs, and optical data storage. I report and demonstrate the newly TiO2-SiO2 ultraviolet curable materials with 20-25 wt% ratio of high titanium for CF4/O2 etch selectivity using nanoimprint lithography process. The multiple structured three-dimensional micro- and nanolines patterns were observed to be successfully patterned over the large areas. The effect of titanium concentration on CF4/O2 etch selectivity with pattern transferring carbon layer imprinting time was investigated. CF4/O2 etching rate of the TiO2-SiO2 ultraviolet curable material was approximately 3.8 times lower than that of the referenced SiO2 sol-gel ultraviolet curable material. The TiO2-SiO2 ultraviolet curable material with high titanium concentration has been proved to be versatile in advanced nanofabrication.

  15. Kearns-Sayre syndrome case presenting a mitochondrial DNA deletion with unusual direct repeats and a rudimentary RNAse mitochondria ribonucleotide processing target sequence

    Energy Technology Data Exchange (ETDEWEB)

    Remes, A.M.; Hassinen, I.E. (Univ. of Oulu (Finland)); Peuhkurinen, K.J.; Herva, R.; Majamaa, K. (Oulu Univ. Central Hospital (Finland))

    1993-04-01

    A mitochondrial DNA deletion in a case of Kearns-Sayre syndrome is described. The deletion is bracketed by direct repeats that were unusual in that one of them was located 11--13 nucleotides from the deletion seam and both were conserved, which should not occur in slip replication or illegitimate elongation. The deleted region was demarcated on the deletion side by sequences that could be predicted to form hairpin structures. The 5[prime]-side of the deletion was flanked by a sequence homologous to a 9-nucleotide piece of the conserved sequence block II of the D-loop. This arrangement around the deletion in Kearns-Sayre syndrome bears some resemblance to the arrangement in the Pearson marrow- pancreas syndrome described by A. Rotig et al. (1991, Genomics 10: 502--504). 10 refs., 1 fig.

  16. One small step: world's first integrated EUVL process line

    Science.gov (United States)

    Roberts, Jeanette M.; Bacuita, Terence; Bristol, Robert L.; Cao, Heidi B.; Chandhok, Manish; Lee, Sang H.; Panning, Eric M.; Shell, Melissa; Zhang, Guojing; Rice, Bryan J.

    2005-05-01

    The Intel lithography roadmap calls for Extreme Ultraviolet Lithography (EUVL) to be used for the 32 nm node. With the installation of the EUV Micro-Exposure Tool (MET) complete, Intel now has the world's first integrated EUVL process line including the first commercial EUV exposure tool. This process line will be used to develop the EUV technology, including mask and resist, and to investigate issues such as defect printability. It also provides a test-bed to discover and resolve problems associated with using this novel technology in a fab (not lab) environment. Over 22,000 fields have been exposed, the discharge-produced plasma light source has operated for 50,000,000 pulses, 8 masks have been fabricated, and 8 resists have been characterized. The MET combines high resolution capability with Intel's advanced processing facilities to prepare EUVL for high-volume manufacturing (HVM). In this paper we review the MET installation and facilities, novel capabilities of the linked track, data on optics quality and modeled tool capability, and the MET mask fabrication process. We present data on tool performance including printing 45 nm 1/2 pitch lines with 160 nm depth of focus and 27 nm isolated lines. We show tool accuracy and repeatability data, and discuss issues uncovered during installation and use.

  17. Particulate templates and ordered liquid bridge networks in evaporative lithography.

    Science.gov (United States)

    Vakarelski, Ivan U; Kwek, Jin W; Tang, Xiaosong; O'Shea, Sean J; Chan, Derek Y C

    2009-12-01

    We investigate the properties of latex particle templates required to optimize the development of ordered liquid bridge networks in evaporative lithography. These networks are key precursors in the assembly of solutions of conducting nanoparticles into large, optically transparent, and conducting microwire networks on substrates (Vakarelski, I. U.; Chan, D. Y. C.; Nonoguchi, T.; Shinto, H.; Higashitani, K. Phys. Rev. Lett., 2009, 102, 058303). An appropriate combination of heat treatment and oxygen plasma etching of a close-packed latex particle monolayer is shown to create open-spaced particle templates which facilitates the formation of ordered fully connected liquid bridge networks that are critical to the formation of ordered microwire networks. Similar results can also be achieved if non-close-packed latex particle templates with square or honeycomb geometries are used. The present results have important implications for the development of the particulate templates to control the morphology of functional microwire networks by evaporative lithography.

  18. Functionalized SU-8 patterned with X-ray Lithography

    DEFF Research Database (Denmark)

    Balslev, Søren; Romanato, F.

    2005-01-01

    In this work we demonstrate the feasibility of x-ray lithography on SU-8 photoresist doped with the laser dye Rhodamine 6G, while retaining the photoactive properties of the embedded dye. Two kinds of structures are fabricated via soft x-ray lithography and characterized: a laser and in amplified...... spontaneous emission light source that couples out light normal to the chip plane. In addition we examine the influence of the x-ray irradiation on the fluorescence of thin films of dye doped SU-8. The dye embedded in the SU-8 is optically excited during, characterization by an external light source tuned...... to the absorption band of the dye. (c) 2005 American Iaviuon SocietY....

  19. Bioimprinting strategies: from soft lithography to biomimetic sensors and beyond.

    Science.gov (United States)

    Mujahid, Adnan; Iqbal, Naseer; Afzal, Adeel

    2013-12-01

    Imprinting is a straightforward, yet a reliable technique to develop dynamic artificial recognition materials-so called as synthetic antibodies. Surface imprinting strategies such as soft lithography allow biological stereotyping of polymers and sol-gel phases to prepare extremely selective receptor layers, which can be combined with suitable transducer systems to develop high performance biomimetic sensors. This article presents an overview of the remarkable technical advancements in the field of surface bioimprinting with particular emphasis on surface imprinted bioanalyte detection systems and their applications in rapid bioanalysis and biotechnology. Herein, we discuss a variety of surface imprinting strategies including soft lithography, template immobilization, grafting, emulsion polymerization, and others along with their biomimetic sensor applications, merits and demerits. The pioneering research works on surface patterned biosensors are described with selected examples of detecting biological agents ranging from small biomolecules and proteins to living cells and microorganisms. © 2013.

  20. Fabrication of Nonperiodic Metasurfaces by Microlens Projection Lithography.

    Science.gov (United States)

    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.

  1. XUV free-electron laser-based projection lithography systems

    Energy Technology Data Exchange (ETDEWEB)

    Newnam, B.E.

    1990-01-01

    Free-electron laser sources, driven by rf-linear accelerators, have the potential to operate in the extreme ultraviolet (XUV) spectral range with more than sufficient average power for high-volume projection lithography. For XUV wavelengths from 100 nm to 4 nm, such sources will enable the resolution limit of optical projection lithography to be extended from 0.25 {mu}m to 0.05{mu}m and with an adequate total depth of focus (1 to 2 {mu}m). Recent developments of a photoinjector of very bright electron beams, high-precision magnetic undulators, and ring-resonator cavities raise our confidence that FEL operation below 100 nm is ready for prototype demonstration. We address the motivation for an XUV FEL source for commercial microcircuit production and its integration into a lithographic system, include reflecting reduction masks, reflecting XUV projection optics and alignment systems, and surface-imaging photoresists. 52 refs., 7 figs.

  2. Influence of Immersion Lithography on Wafer Edge Defectivity

    OpenAIRE

    Jami, K.; Pollentier, I.; Vedula, S; Blumenstock, G

    2010-01-01

    In this paper, we investigated the impact of immersion lithography on wafer edge defectivity. In the past, such work has been limited to inspection of the flat top part of the wafer edge due to the inspection challenges at the curved wafer edge and lack of a comprehensive defect inspection solution. Our study used a new automated edge inspection system that provides full wafer edge imaging and automatic defect classification. The work revealed several key challenges to controlling wafer edge-...

  3. Tunable Nanopatterning of Conductive Polymers via Electrohydrodynamic Lithography

    OpenAIRE

    Rickard, Jonathan James Stanley; Farrer, Ian; Goldberg Oppenheimer, Pola

    2016-01-01

    An increasing number of technologies require the fabrication of conductive structures on a broad range of scales and over large areas. Here, we introduce advanced yet simple electrohydrodynamic lithography (EHL) for patterning conductive polymers directly on a substrate with high fidelity. We illustrate the generality of this robust, low-cost method by structuring thin polypyrrole films via electric-field-induced instabilities, yielding well-defined conductive structures with feature sizes ra...

  4. Mask-less lithography for fabrication of optical waveguides

    Science.gov (United States)

    Dubov, M.; Natarajan, S. R.; Williams, J. A. R.; Bennion, I.

    2008-02-01

    A flexible method for fabricating shallow optical waveguides by using femtosecond laser writing of patterns on a metal coated glass substrate followed by ion-exchange is described. This overcomes the drawbacks of low index contrast and high induced stress in waveguides directly written using low-repetition rate ultrafast laser systems. When compared to conventional lithography, the technique is simpler and has advantages in terms of flexibility in the types of structures which can be fabricated.

  5. RuMBa: a rule-model OPC for low MEEF 130-nm KrF lithography

    Science.gov (United States)

    Hsu, Stephen; Shi, Xuelong; Hsu, Chungwei Michael; Corcoran, Noel P.; Chen, J. Fung; Desai, Sunil; Sherrill, Micheal J.; Tseng, Y. C.; Chang, H. A.; Kao, J. F.; Tseng, Alex; Liu, WeiJyh; Chen, Anseime; Lin, Arthur; Kujten, Jan P.; Jacobs, Eric; Verhappen, Arjan

    2001-09-01

    For cost effective 130nm node manufacturing, it is prefer to use KrF binary chrome mask. To realize a production worth process for making random logic device, we need to effectively control mask error enhancement factor (MEEF) through pitch. In low k1 lithography, process parameters such as focus, lens aberration, linewidth, and line pitch, style of proximity correction (OPC), and resist process conditions, etc., all impact MEEF. We show a powerful RuMBa OPC method that can reduce MEEF to an acceptable level (close to 1(using KrF resist process. We believe that RuMBa OPC method can be further extended for sub 100nm ArF process. In wafer printing experiment, we have designed a new style of LineSweeper reticles for our lithography process optimization. Both simulated and printed wafer CD data were used to calculate the overlapped process window along with respective MEEF. These are the metric we used to assess the 130nm process performance. Using RuMBa OPC, we are able to achieve overlapped process window that is sufficient for 130nm gate mask process. The CD through pitch calibration is critical for an accurate model-based correct at location where OPC rule cannot cover. A high accuracy CD through pitch calibration methodology is developed for model calibration. In this paper, we have compared the 130nm performance using KrF binary mask, KrF 6% attenuated PSM, and ArF binary mask.

  6. Reconfigurable multiport EPON repeater

    Science.gov (United States)

    Oishi, Masayuki; Inohara, Ryo; Agata, Akira; Horiuchi, Yukio

    2009-11-01

    An extended reach EPON repeater is one of the solutions to effectively expand FTTH service areas. In this paper, we propose a reconfigurable multi-port EPON repeater for effective accommodation of multiple ODNs with a single OLT line card. The proposed repeater, which has multi-ports in both OLT and ODN sides, consists of TRs, BTRs with the CDR function and a reconfigurable electrical matrix switch, can accommodate multiple ODNs to a single OLT line card by controlling the connection of the matrix switch. Although conventional EPON repeaters require full OLT line cards to accommodate subscribers from the initial installation stage, the proposed repeater can dramatically reduce the number of required line cards especially when the number of subscribers is less than a half of the maximum registerable users per OLT. Numerical calculation results show that the extended reach EPON system with the proposed EPON repeater can save 17.5% of the initial installation cost compared with a conventional repeater, and can be less expensive than conventional systems up to the maximum subscribers especially when the percentage of ODNs in lightly-populated areas is higher.

  7. Revisiting the TALE repeat.

    Science.gov (United States)

    Deng, Dong; Yan, Chuangye; Wu, Jianping; Pan, Xiaojing; Yan, Nieng

    2014-04-01

    Transcription activator-like (TAL) effectors specifically bind to double stranded (ds) DNA through a central domain of tandem repeats. Each TAL effector (TALE) repeat comprises 33-35 amino acids and recognizes one specific DNA base through a highly variable residue at a fixed position in the repeat. Structural studies have revealed the molecular basis of DNA recognition by TALE repeats. Examination of the overall structure reveals that the basic building block of TALE protein, namely a helical hairpin, is one-helix shifted from the previously defined TALE motif. Here we wish to suggest a structure-based re-demarcation of the TALE repeat which starts with the residues that bind to the DNA backbone phosphate and concludes with the base-recognition hyper-variable residue. This new numbering system is consistent with the α-solenoid superfamily to which TALE belongs, and reflects the structural integrity of TAL effectors. In addition, it confers integral number of TALE repeats that matches the number of bound DNA bases. We then present fifteen crystal structures of engineered dHax3 variants in complex with target DNA molecules, which elucidate the structural basis for the recognition of bases adenine (A) and guanine (G) by reported or uncharacterized TALE codes. Finally, we analyzed the sequence-structure correlation of the amino acid residues within a TALE repeat. The structural analyses reported here may advance the mechanistic understanding of TALE proteins and facilitate the design of TALEN with improved affinity and specificity.

  8. Nanoimprint, DSA, and multi-beam lithography: patterning technologies with new integration challenges

    Science.gov (United States)

    Landis, S.; Teyssedre, H.; Claveau, G.; Servin, I.; Delachat, F.; Pourteau, M. L.; Gharbi, A.; Pimenta Barros, P.; Tiron, R.; Nouri, L.; Possemé, N.; May, M.; Brianceau, P.; Barnola, S.; Blancquaert, Y.; Pradelles, J.; Essomba, P.; Bernadac, A.; Dal'zotto, B.; Bos, S.; Argoud, M.; Chamiot-Maitral, G.; Sarrazin, A.; Tallaron, C.; Lapeyre, C.; Pain, L.

    2017-04-01

    In the lithography landscape, EUV technology recovered some credibility recently. However, its large adoption remains uncertain. Meanwhile, 193nm immersion lithography, with multiple-patterning strategies, supports the industry preference for advanced-node developments. In this landscape, lithography alternatives maintain promise for continued R&D. Massively parallel electron-beam and nano-imprint lithography techniques remain highly attractive, as they can provide noteworthy cost-of-ownership benefits. Directed self-assembly lithography shows promising resolution capabilities and appears to be an option to reduce multi-patterning strategies. Even if large amount of efforts are dedicated to overcome the lithography side issues, these solutions introduce also new challenges and opportunities for the integration schemes.

  9. Lithography development and research challenges for the pitch

    Science.gov (United States)

    Wurm, Stefan

    2009-01-01

    For the 32 and 22 nm half-pitch nodes of the International Technology Roadmap for Semiconductors, the industry will face the challenge of introducing new lithography technologies into manufacturing. Some can build on the extension of current optical lithography technologies. However, others require a tool, optics, mask, and resist infrastructure quite different from those supporting today's manufacturing. Developing new technology solutions for use in manufacturing takes a long time and the final stages of infrastructure development and commercialization are very costly. The readiness of lithography technologies needs to be assessed based on development progress, but it also needs to consider whether a technology receives the necessary support to intersect a given technology node. In addition to being technically challenging, enabling an infrastructure capable of supporting pilot line and then high volume manufacturing insertion on an aggressive timeline is also a significant business challenge. To share the risk and cost, the industry must consider new business models for efficient collaboration with tool and infrastructure suppliers on the one side and device manufacturers on the other.

  10. Pixelated source and mask optimization for immersion lithography.

    Science.gov (United States)

    Ma, Xu; Han, Chunying; Li, Yanqiu; Dong, Lisong; Arce, Gonzalo R

    2013-01-01

    Immersion lithography systems with hyper-numerical aperture (hyper-NA) (NA>1) have become indispensable in nanolithography for technology nodes of 45 nm and beyond. Source and mask optimization (SMO) has emerged as a key technique used to further improve the imaging performance of immersion lithography. Recently, a set of pixelated gradient-based SMO approaches were proposed under the scalar imaging models, which are inaccurate for hyper-NA settings. This paper focuses on developing pixelated gradient-based SMO algorithms based on a vector imaging model that is accurate for current immersion lithography. To achieve this goal, an integrative and analytic vector imaging model is first used to formulate the simultaneous SMO (SISMO) and sequential SMO (SESMO) frameworks. A gradient-based algorithm is then exploited to jointly optimize the source and mask. Subsequently, this paper studies and compares the performance of individual source optimization (SO), individual mask optimization (MO), SISMO, and SESMO. Finally, a hybrid SMO (HSMO) approach is proposed to take full advantage of SO, SISMO, and MO, consequently achieving superior performance.

  11. Fabrication of 70nm split ring resonators by nanoimprint lithography

    Science.gov (United States)

    Sharp, Graham J.; Khokhar, Ali Z.; Johnson, Nigel P.

    2012-05-01

    We report on the fabrication of 70 nm wide, high resolution rectangular U-shaped split ring resonators (SRRs) using nanoimprint lithography (NIL). The fabrication method for the nanoimprint stamp does not require dry etching. The stamp is used to pattern SRRs in a thin PMMA layer followed by metal deposition and lift-off. Nanoimprinting in this way allows high resolution patterns with a minimum feature size of 20 nm. This fabrication technique yields a much higher throughput than conventional e-beam lithography and each stamp can be used numerous times to imprint patterns. Reflectance measurements of fabricated aluminium SRRs on silicon substrates show a so-called an LC resonance peak in the visible spectrum under transverse electric polarisation. Fabricating the SRRs by NIL rather than electron beam lithography allows them to be scaled to smaller dimensions without any significant loss in resolution, partly because pattern expansion caused by backscattered electrons and the proximity effect are not present with NIL. This in turn helps to shift the magnetic response to short wavelengths while still retaining a distinct LC peak.

  12. Oblique Colloidal Lithography for the Fabrication of Nonconcentric Features.

    Science.gov (United States)

    Zhao, Zhi; Cao, Yang; Cai, Yangjun; Yang, Jian; He, Ximin; Nordlander, Peter; Cremer, Paul S

    2017-07-25

    Herein, we describe the development of oblique colloidal lithography (OCL) and establish a systematic patterning strategy for creating libraries of nanosized nonconcentric plasmonic structures. This strategy combines OCL, capillary force lithography, and several wet and ion etching steps. Hexagonal arrays of nonconcentric gold features were created on glass substrates with highly controllable geometric parameters. The size, geometry, and eccentricity of the gold features could be independently tuned by controlling the experimental conditions. Gaps within surface elements could be shrunk to as small as 30 nm, while the total patterned area was about l cm(2). The goal was to devise a method that offers a high degree of control over the resolution and morphology of asymmetric structures without the need to resort to electron beam lithography. This technique also enabled the development of numerous surface patterns through the stepwise fabrication of separate elements. Complex features, including dots-surrounded nonconcentric targets, nonconcentric hexagram-disks, and nonconcentric annular aperture arrays, were demonstrated, and their optical properties were characterized. Indeed, spectroscopic studies and FDTD simulations demonstrated that Fano resonances could readily be generated by the nonconcentric gold features. Consequently, our patterning strategy should enable the high-throughput investigation of plasmonic coupling and Fano resonances as a function of the physical parameters of the elements within the nanopattern array.

  13. High-throughput jet and flash imprint lithography for advanced semiconductor memory

    Science.gov (United States)

    Khusnatdinov, Niyaz; Ye, Zhengmao; Luo, Kang; Stachowiak, Tim; Lu, Xiaoming; Irving, J. W.; Shafran, Matt; Longsine, Whitney; Traub, Matthew; Truskett, Van; Fletcher, Brian; Liu, Weijun; Xu, Frank; LaBrake, Dwayne; Sreenivasan, S. V.

    2014-03-01

    Imprint lithography has been shown to be an effective technique for replication of nano-scale features. Jet and Flash Imprint Lithography (J-FIL) involves the field-by-field deposition and exposure of a low viscosity resist deposited by jetting technology onto the substrate. The patterned mask is lowered into the 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. Non-fill defectivity must always be considered within the context of process throughput. Processing steps such as resist exposure time and mask/wafer separation are well understood, and typical times for the steps are on the order of 0.10 to 0.20 seconds. To achieve a total process throughput of 20 wafers per hour (wph), it is necessary to complete the fluid fill step in 1.0 seconds, making it the key limiting step in an imprint process. Recently, defect densities of less than 1.0/cm2 have been achieved at a fill time of 1.2 seconds by reducing resist drop size and optimizing the drop pattern. 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. This paper addresses the improvements made with reduced drop volume and enhanced surface wetting to demonstrate that fast filling can be achieved for both full fields and edge fields. By incorporating the changes to the process noted above, we are now attaining fill times of 1 second with non-fill defectivity of ~ 0.1 defects/cm2.

  14. High throughput Jet and Flash Imprint Lithography for semiconductor memory applications

    Science.gov (United States)

    Zhang, Wei; Fletcher, Brian; Thompson, Ecron; Liu, Weijun; Stachowiak, Tim; Khusnatdinov, Niyaz; Irving, J. W.; Longsine, Whitney; Traub, Matthew; Truskett, Van; LaBrake, Dwayne; Ye, Zhengmao

    2016-03-01

    Imprint lithography has been shown to be an effective technique for replication of nano-scale features. Jet and Flash* Imprint Lithography (J-FIL*) involves the field-by-field deposition and exposure of a low viscosity resist deposited by jetting technology onto the substrate. The patterned mask is lowered into the 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 15 wafers per hour (wph) for a single station, it is necessary to complete the fluid fill step in 1.5 seconds. For a throughput of 20 wph, fill time must be reduced to only one second. 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 enable a 1.50 second filling process for a sub-20nm device like pattern and have demonstrated this capability

  15. Repeatability of Harris Corner Detector

    Institute of Scientific and Technical Information of China (English)

    HU Lili

    2003-01-01

    Interest point detectors are commonly employed to reduce the amount of data to be processed. The ideal interest point detector would robustly select those features which are most appropriate or salient for the application and data at hand. This paper shows that interest points are geometrically stable under different transformations.This property makes interest points very successful in the context of image matching. To measure this property quantatively, we introduce a evaluation criterion: repeatability rate.

  16. Fabrication of nanostructures on polyethylene terephthalate substrate by interference lithography and plasma etching.

    Science.gov (United States)

    Zhu, Mei; Li, Bihan; Choi, W K

    2013-08-01

    We report results of an attempt to create nanostructures on polyethylene terephthalate substrate using the interference lithography and plasma etching technique. Methods to create nanogrooves, nanopillars, nanofins and nanoholes have been presented. The effects of chemical and physical etching associated with plasma etching on the synthesis of nanostructures were examined in detail. Different etch rates and anisotropy as a function of plasma power and pressure were reported and explained, offering good understanding of the physics of the etching process. Ways to improve anisotropy have been suggested and experimentally verified. We show that this method can produce nanostructured substrate with wide surface coverage and good uniformity. The flexibility of this method was demonstrated in that the period and shapes of the nanopattern can be varied easily without resorting to complicated fabrication processes and machinery. Our method brings forth an easy and cost-effective way to create uniform nanostructures on a large area in a controllable fashion.

  17. Improvement of silicon nanowire solar cells made by metal catalyzed electroless etching and nano imprint lithography

    Science.gov (United States)

    Chen, Junyi; Subramani, Thiyagu; Jevasuwan, Wipakorn; Fukata, Naoki

    2017-04-01

    Silicon nanowires were fabricated by metal catalyzed electroless etching (MCEE) and nano imprint lithography (NIL), then a shell p-type layer was grown by thermal chemical vapor deposition (CVD) techniques. To reduce back surface recombination and also to activate the dopant, we used two techniques, back surface field (BSF) treatment and rapid thermal annealing (RTA), to improve device performance. In this study, we investigated BSF and RTA treatments in silicon nanowire solar cells, and improved the device performance and efficiency from 4.1 to 7.4% (MCEE device) and from 1.1 to 6.6% (NIL device) after introducing BSF and RTA treatments. Moreover, to achieve better metal contact without sacrificing the reflectance after the shell formation, the selective-area etching method was investigated. Finally, after combining all processes, silicon nanowire solar cells fabricated via the MCEE process exhibited 8.7% efficiency.

  18. Orthogonal Patterning of Multiple Biomolecules Using an Organic Fluorinated Resist and Imprint Lithography

    Science.gov (United States)

    Midthun, Kari M.; Taylor, Priscilla G.; Newby, Carol; Chatzichristidi, Margarita; Petrou, Panagiota S.; Lee, Jin-Kyun; Kakabakos, Sotiris E.; Baird, Barbara A.; Ober, Christopher K.

    2013-01-01

    The ability to spatially deposit multiple biomolecules onto a single surface with high-resolution while retaining biomolecule stability and integrity is critical to the development of micro- and nanoscale bio-devices. While conventional lithographic patterning methods are attractive for this application, they typically require the use of UV exposure and/or harsh solvents and imaging materials, which may be damaging to fragile biomolecules. Here, we report the development of a new patterning process based on a fluorinated patterning material that is soluble in hydrofluoroether solvents, which we show to be benign to biomolecules, including proteins and DNA. We demonstrate the implementation of these materials into an orthogonal processing system for patterning multi-biomolecule arrays by imprint lithography at room temperature. We further showcase this method’s capacity for fabricating patterns of receptor-specific ligands for fundamental cell studies. PMID:23439033

  19. Dynamics of wicking in silicon nanopillars fabricated with interference lithography and metal-assisted chemical etching.

    Science.gov (United States)

    Mai, Trong Thi; Lai, Chang Quan; Zheng, H; Balasubramanian, Karthik; Leong, K C; Lee, P S; Lee, Chengkuo; Choi, W K

    2012-08-07

    The capillary rise of liquid on a surface, or "wicking", has potential applications in biological and industrial processes such as drug delivery, oil recovery, and integrated circuit chip cooling. This paper presents a theoretical study on the dynamics of wicking on silicon nanopillars based on a balance between the driving capillary forces and viscous dissipation forces. Our model predicts that the invasion of the liquid front follows a diffusion process and strongly depends on the structural geometry. The model is validated against experimental observations of wicking in silicon nanopillars with different heights synthesized by interference lithography and metal-assisted chemical etching techniques. Excellent agreement between theoretical and experimental results, from both our samples and data published in the literature, was achieved.

  20. Silicon dioxide mask by plasma enhanced atomic layer deposition in focused ion beam lithography

    Science.gov (United States)

    Liu, Zhengjun; Shah, Ali; Alasaarela, Tapani; Chekurov, Nikolai; Savin, Hele; Tittonen, Ilkka

    2017-02-01

    In this work, focused ion beam (FIB) lithography was developed for plasma enhanced atomic layer deposited (PEALD) silicon dioxide SiO2 hard mask. The PEALD process greatly decreases the deposition temperature of the SiO2 hard mask. FIB Ga+ ion implantation on the deposited SiO2 layer increases the wet etch resistivity of the irradiated region. A programmed exposure in FIB followed by development in a wet etchant enables the precisely defined nanoscale patterning. The combination of FIB exposure parameters and the development time provides greater freedom for optimization. The developed process provides high pattern dimension accuracy over the tested range of 90–210 nm. Utilizing the SiO2 mask developed in this work, silicon nanopillars with 40 nm diameter were successfully fabricated with cryogenic deep reactive ion etching and the aspect ratio reached 16:1. The fabricated mask is suitable for sub-100 nm high aspect ratio silicon structure fabrication.

  1. Recursive quantum repeater networks

    CERN Document Server

    Van Meter, Rodney; Horsman, Clare

    2011-01-01

    Internet-scale quantum repeater networks will be heterogeneous in physical technology, repeater functionality, and management. The classical control necessary to use the network will therefore face similar issues as Internet data transmission. Many scalability and management problems that arose during the development of the Internet might have been solved in a more uniform fashion, improving flexibility and reducing redundant engineering effort. Quantum repeater network development is currently at the stage where we risk similar duplication when separate systems are combined. We propose a unifying framework that can be used with all existing repeater designs. We introduce the notion of a Quantum Recursive Network Architecture, developed from the emerging classical concept of 'recursive networks', extending recursive mechanisms from a focus on data forwarding to a more general distributed computing request framework. Recursion abstracts independent transit networks as single relay nodes, unifies software layer...

  2. UK 2009-2010 repeat station report

    Directory of Open Access Journals (Sweden)

    Thomas J.G. Shanahan

    2013-03-01

    Full Text Available The British Geological Survey is responsible for conducting the UK geomagnetic repeat station programme. Measurements made at the UK repeat station sites are used in conjunction with the three UK magnetic observatories: Hartland, Eskdalemuir and Lerwick, to produce a regional model of the local field each year. The UK network of repeat stations comprises 41 stations which are occupied at approximately 3-4 year intervals. Practices for conducting repeat station measurements continue to evolve as advances are made in survey instrumentation and as the usage of the data continues to change. Here, a summary of the 2009 and 2010 UK repeat station surveys is presented, highlighting the measurement process and techniques, density of network, reduction process and recent results.

  3. Polymer blend lithography: A versatile method to fabricate nanopatterned self-assembled monolayers

    Directory of Open Access Journals (Sweden)

    Cheng Huang

    2012-09-01

    Full Text Available A rapid and cost-effective lithographic method, polymer blend lithography (PBL, is reported to produce patterned self-assembled monolayers (SAM on solid substrates featuring two or three different chemical functionalities. For the pattern generation we use the phase separation of two immiscible polymers in a blend solution during a spin-coating process. By controlling the spin-coating parameters and conditions, including the ambient atmosphere (humidity, the molar mass of the polystyrene (PS and poly(methyl methacrylate (PMMA, and the mass ratio between the two polymers in the blend solution, the formation of a purely lateral morphology (PS islands standing on the substrate while isolated in the PMMA matrix can be reproducibly induced. Either of the formed phases (PS or PMMA can be selectively dissolved afterwards, and the remaining phase can be used as a lift-off mask for the formation of a nanopatterned functional silane monolayer. This “monolayer copy” of the polymer phase morphology has a topographic contrast of about 1.3 nm. A demonstration of tuning of the PS island diameter is given by changing the molar mass of PS. Moreover, polymer blend lithography can provide the possibility of fabricating a surface with three different chemical components: This is demonstrated by inducing breath figures (evaporated condensed entity at higher humidity during the spin-coating process. Here we demonstrate the formation of a lateral pattern consisting of regions covered with 1H,1H,2H,2H-perfluorodecyltrichlorosilane (FDTS and (3-aminopropyltriethoxysilane (APTES, and at the same time featuring regions of bare SiOx. The patterning process could be applied even on meter-sized substrates with various functional SAM molecules, making this process suitable for the rapid preparation of quasi two-dimensional nanopatterned functional substrates, e.g., for the template-controlled growth of ZnO nanostructures.

  4. Integrated one diode-one resistor architecture in nanopillar SiOx resistive switching memory by nanosphere lithography.

    Science.gov (United States)

    Ji, Li; Chang, Yao-Feng; Fowler, Burt; Chen, Ying-Chen; Tsai, Tsung-Ming; Chang, Kuan-Chang; Chen, Min-Chen; Chang, Ting-Chang; Sze, Simon M; Yu, Edward T; Lee, Jack C

    2014-02-12

    We report on a highly compact, one diode-one resistor (1D-1R) nanopillar device architecture for SiOx-based ReRAM fabricated using nanosphere lithography (NSL). The intrinsic SiOx-based resistive switching element and Si diode are self-aligned on an epitaxial silicon wafer using NSL and a deep-Si-etch process without conventional photolithography. AC-pulse response in 50 ns regime, multibit operation, and good reliability are demonstrated. The NSL process provides a fast and economical approach to large-scale patterning of high-density 1D-1R ReRAM with good potential for use in future applications.

  5. A lithography aware design optimization using foundry-certified models and hotspot detection

    Science.gov (United States)

    Karklin, L.; Arkhipov, A.; Blakely, D.; Dingenen, M.; Mehrotra, A.; Watson, B.; Zelnik, C.; Cote, M.; Hurat, P.

    2007-10-01

    An automated litho-aware design migration solution has been implemented to enable designers to port existing IP layouts (custom, library, and block) to nanometer technologies while optimizing layout printability and silicon yield. With rapidly shrinking technology nodes, the industry consolidation toward fabless or fab-lite manufacturing, demand for second-sourcing and dramatic increase in cost of IP development, the automation of "vertical" (between nodes) and 'horizontal" (between chip manufacturers) migration becomes a very important task. The challenge comes from the fact that even within the same technology node design and process-induced rules deviate substantially among different IDMs and foundries, which leads to costly, error-prone and time consuming design modifications. At the same time, fast and reliable adjustments to design and ability to switch between processes and chip manufacturers could represent significant improvement to TTM, and respectively improving ROI. Using conservative rules (or restricted design rules) is not always a viable option because of the area, performance and yield penalties. The difficulty of migration is augmented by the fact that design rules are not sufficient to guaranty good printability, maximum process window and high yield. Model-based detection of lithography-induced systematic yield-limiting defects (a.k.a. hotspots) is becoming a vital part of the design-for-manufacturing flow for advanced technology nodes at 65nm and below. Driven by customer demand, a collaborative effort between EDA vendors provides a complete design-for-manufacturing migration solution that allows sub-65 nanometer designers to comprehensively address the impact of manufacturing variations on design yield and performance during layout migration. First, the physical hard IP is migrated from its existing 90nm process to a more advanced 65 and 45 nm processes, resulting in an area-optimized DRC-clean 65nm design retaining the original hierarchy to

  6. Concave diffraction gratings fabricated with planar lithography

    NARCIS (Netherlands)

    Grabarnik, S.; Emadi, A.; Wu, H.; De Graaf, G.; Wolffenbuttel, R.F.

    2008-01-01

    This paper reports on the development and validation of a new technology for the fabrication of variable line-spacing non-planar diffraction gratings to be used in compact spectrometers. The technique is based on the standard lithographic process commonly used for pattern transfer onto a flat substr

  7. Improving repeatability by improving quality

    Energy Technology Data Exchange (ETDEWEB)

    Ronen, Shuki; Ackers, Mark; Schlumberger, Geco-Prakla; Brink, Mundy

    1998-12-31

    Time lapse (4-D) seismic is a promising tool for reservoir characterization and monitoring. The method is apparently simple: to acquire data repeatedly over the same reservoir, process and interpret the data sets, then changes between the data sets indicate changes in the reservoir. A problem with time lapse seismic data is that reservoirs are a relatively small part of the earth and important reservoir changes may cause very small differences to the time lapse data. The challenge is to acquire and process economical time lapse data such that reservoir changes can be detected above the noise of varying acquisition and environment. 7 refs., 9 figs.

  8. A comprehensive simulation model of the performance of photochromic films in absorbance-modulation-optical-lithography

    Science.gov (United States)

    Majumder, Apratim; Helms, Phillip L.; Andrew, Trisha L.; Menon, Rajesh

    2016-03-01

    Optical lithography is the most prevalent method of fabricating micro-and nano-scale structures in the semiconductor industry due to the fact that patterning using photons is fast, accurate and provides high throughput. However, the resolution of this technique is inherently limited by the physical phenomenon of diffraction. Absorbance-Modulation-Optical Lithography (AMOL), a recently developed technique has been successfully demonstrated to be able to circumvent this diffraction limit. AMOL employs a dual-wavelength exposure system in conjunction with spectrally selective reversible photo-transitions in thin films of photochromic molecules to achieve patterning of features with sizes beyond the far-field diffraction limit. We have developed a finite-element-method based full-electromagnetic-wave solution model that simulates the photo-chemical processes that occur within the thin film of the photochromic molecules under illumination by the exposure and confining wavelengths in AMOL. This model allows us to understand how the material characteristics influence the confinement to sub-diffraction dimensions, of the transmitted point spread function (PSF) of the exposure wavelength inside the recording medium. The model reported here provides the most comprehensive analysis of the AMOL process to-date, and the results show that the most important factors that govern the process, are the polarization of the two beams, the ratio of the intensities of the two wavelengths, the relative absorption coefficients and the concentration of the photochromic species, the thickness of the photochromic layer and the quantum yields of the photoreactions at the two wavelengths. The aim of this work is to elucidate the requirements of AMOL in successfully circumventing the far-field diffraction limit.

  9. A comprehensive simulation model of the performance of photochromic films in absorbance-modulation-optical-lithography

    Directory of Open Access Journals (Sweden)

    Apratim Majumder

    2016-03-01

    Full Text Available Optical lithography is the most prevalent method of fabricating micro-and nano-scale structures in the semiconductor industry due to the fact that patterning using photons is fast, accurate and provides high throughput. However, the resolution of this technique is inherently limited by the physical phenomenon of diffraction. Absorbance-Modulation-Optical Lithography (AMOL, a recently developed technique has been successfully demonstrated to be able to circumvent this diffraction limit. AMOL employs a dual-wavelength exposure system in conjunction with spectrally selective reversible photo-transitions in thin films of photochromic molecules to achieve patterning of features with sizes beyond the far-field diffraction limit. We have developed a finite-element-method based full-electromagnetic-wave solution model that simulates the photo-chemical processes that occur within the thin film of the photochromic molecules under illumination by the exposure and confining wavelengths in AMOL. This model allows us to understand how the material characteristics influence the confinement to sub-diffraction dimensions, of the transmitted point spread function (PSF of the exposure wavelength inside the recording medium. The model reported here provides the most comprehensive analysis of the AMOL process to-date, and the results show that the most important factors that govern the process, are the polarization of the two beams, the ratio of the intensities of the two wavelengths, the relative absorption coefficients and the concentration of the photochromic species, the thickness of the photochromic layer and the quantum yields of the photoreactions at the two wavelengths. The aim of this work is to elucidate the requirements of AMOL in successfully circumventing the far-field diffraction limit.

  10. Double dipole lithography for 65-nm node and beyond: defect sensitivity characterization and reticle inspection

    Science.gov (United States)

    Hsu, Stephen; Chu, Tsann-bin; Van Den Broeke, Douglas; Chen, J. Fung; Hsu, Michael; Corcoran, Noel P.; Volk, William; Ruch, Wayne E.; Sier, Jean-Paul E.; Hess, Carl E.; Lin, Benjamin S.; Yu, Chun-Chi; Huang, George

    2004-12-01

    Double Dipole Lithography (DDLä) has been demonstrated to be capable of patterning complex 2D devices patterns. [1,2,3] Due to inherently high aerial image contrast from dipole illumination, we have found that it can meet lithography manufacturing requirements, such as line edge roughness (LER), and critical dimension uniformity (CDU), for the upcoming 65nm node using ArF binary chrome masks. For patterning at k1 below 0.35, DDL is one of the promising resolution enhancement techniques (RET), which can offer process latitudes that are comparable to more costly alternatives such as two-exposure alternating PSM. To use DDL for printing actual IC devices, the original design data must be converted into a "vertical (V)" mask and a "horizontal (H)" mask for the respective X-dipole and Y-dipole exposures. We demonstrated that our model-based DDL mask data processing methodology is capable of converting complex 2D logic and memory designs into dipole-compatible mask layouts. [2,3] Due to the double exposure, stray light must be well controlled to ensure uniform printing across the entire chip. One intuitive solution to minimize stray light is to apply large patches of chrome in the open field areas in order to reduce the background (non-pattern area) exposure level. Unfortunately, this is not viable for a clear-field poly gate mask as it incorporates a positive photoresist process. We developed an innovative and practical background-shielding scheme called sub-resolution grating block (SGB), which is part of the DDL layout conversion method for full-chip application. This technique can effectively minimize the impact of long-range stray light on critical features during the two exposures. Reticles inspection is another important issue for the implementation of DDL technology. In this work, we reported a methodology on how to characterize defects and optimize inspection sensitivity for DDL RET reticles.

  11. Spun-wrapped aligned nanofiber (SWAN) lithography for fabrication of micro/nano-structures on 3D objects

    Science.gov (United States)

    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

  12. 法夫酵母产虾青素的反复分批及反复分批补料发酵%Repeated batch and fed-batch process for astaxanthin production by Phaffia rhodozyma

    Institute of Scientific and Technical Information of China (English)

    肖安风; 倪辉; 李利君; 蔡慧农

    2011-01-01

    A comparative study of batch and repeated batch process was carried out for astaxanthin fermentation of Phaffia rhodozyma to develop a more economical method for astaxanthin industrial production. In shaking flask fermentation, the change of biomass and astaxanthin production was studied to compare the five-day cycle with four-day cycle of repeated batch culture of P. thodozyma. Astaxanthin production increased at first and then decreased subsequently in seven cycles, yet the yield of astaxanthin in the next six cycles remains higher than that of the first cycle. Comparing the average production of astaxanthin in the seven cycles, four-day cycle performed even better than five-day cycle. Subsequently, a repeated fed-batch process was used in a 5-1 bioreactor. The experimental data showed that biomass and astaxanthin production of the second batch could reach the level of the first batch, no matter that the carbon source was glucose or hydrolysis sugar of starch. This result showed that this strain had good stability, and thus repeated batch and fed-batch process could be applied in astaxanthin fermentation for economical purpose.%以生物量和虾青素产量为指标,考察法夫酵母多批次半连续培养产虾青素的稳定性.实验结果显示,在摇瓶上分别以4 d和5 d为周期反复分批培养法夫酵母,虾青素产量呈现先增加再下降的趋势,但第2代至第7代虾青素产量仍高于第 1代,并且4 d为周期的虾青素平均产量略高于5 d的.在5 L罐法夫酵母进行反复分批补料发酵中,不管是补加30%的葡萄糖还是补加30%的淀粉水解糖,第2个批次发酵的生物量和虾青素产量均达到第1个批次的水平,表明菌种稳定性较好.

  13. Micro-macro hybrid soft-lithography master (MMHSM) fabrication for lab-on-a-chip applications.

    Science.gov (United States)

    Park, Jaewon; Li, Jianrong; Han, Arum

    2010-04-01

    We present a novel micro-macro hybrid soft-lithography master (MMHSM) fabrication technique where microdevices having both microscale and macroscale features can be replicated with a single soft-lithography step. A poly(methyl methacrylate) (PMMA) master having macroscale structures was first created by a bench-top milling machine. An imprinting master mold having microscale structures was then imprinted on the PMMA surface through a hot-embossing process to obtain a PMMA master mold. A poly(dimethylsiloxane) (PDMS) master was then replicated from this PMMA master through a standard soft-lithography process. This process allowed both microscale (height: 3-20 microm, width: 20-500 microm) and macroscale (height: 3.5 mm, width: 1.2-7 mm) structures to co-exist on the PDMS master mold, from which final PDMS devices could be easily stamped out in large quantities. Microfluidic structures requiring macroscale dimensions in height, such as reservoirs or fluidic tubing interconnects, could be directly built into PDMS microfluidic devices without the typically used manual punching process. This significantly reduced alignment errors and time required for such manual fabrication steps. In this paper, we successfully demonstrated the utility of this novel hybrid fabrication method by fabricating a PDMS microfluidic device with 40 built-in fluidic interfaces and a PDMS multi-compartment neuron co-culture platform, where millimeter-scale compartments are connected via arrays of 20 microm wide and 200 microm long microfluidic channels. The resulting structures were characterized for the integrity of the transferred pattern sizes and the surface roughness using scanning electron microscopy and optical profilometry.

  14. A method to restrain the charging effect on an insulating substrate in high energy electron beam lithography

    Science.gov (United States)

    Mingyan, Yu; Shirui, Zhao; Yupeng, Jing; Yunbo, Shi; Baoqin, Chen

    2014-12-01

    Pattern distortions caused by the charging effect should be reduced while using the electron beam lithography process on an insulating substrate. We have developed a novel process by using the SX AR-PC 5000/90.1 solution as a spin-coated conductive layer, to help to fabricate nanoscale patterns of poly-methyl-methacrylate polymer resist on glass for phased array device application. This method can restrain the influence of the charging effect on the insulating substrate effectively. Experimental results show that the novel process can solve the problems of the distortion of resist patterns and electron beam main field stitching error, thus ensuring the accuracy of the stitching and overlay of the electron beam lithography system. The main characteristic of the novel process is that it is compatible to the multi-layer semiconductor process inside a clean room, and is a green process, quite simple, fast, and low cost. It can also provide a broad scope in the device development on insulating the substrate, such as high density biochips, flexible electronics and liquid crystal display screens.

  15. The Pentapeptide Repeat Proteins

    Energy Technology Data Exchange (ETDEWEB)

    Vetting,M.; Hegde, S.; Fajardo, J.; Fiser, A.; Roderick, S.; Takiff, H.; Blanchard, J.

    2006-01-01

    The Pentapeptide Repeat Protein (PRP) family has over 500 members in the prokaryotic and eukaryotic kingdoms. These proteins are composed of, or contain domains composed of, tandemly repeated amino acid sequences with a consensus sequence of [S, T,A, V][D, N][L, F]-[S, T,R][G]. The biochemical function of the vast majority of PRP family members is unknown. The three-dimensional structure of the first member of the PRP family was determined for the fluoroquinolone resistance protein (MfpA) from Mycobacterium tuberculosis. The structure revealed that the pentapeptide repeats encode the folding of a novel right-handed quadrilateral {beta}-helix. MfpA binds to DNA gyrase and inhibits its activity. The rod-shaped, dimeric protein exhibits remarkable size, shape and electrostatic similarity to DNA.

  16. Design and testing of planar magnetic micromotors fabricated by deep x-ray lithography and electroplating

    Energy Technology Data Exchange (ETDEWEB)

    Guckel, H.; Christenson, T.R.; Skrobis, K.J.; Klein, J. [Wisconsin Univ., Madison, WI (United States). Dept. of Electrical and Computer Engineering; Karnowsky, M. [Sandia National Labs., Albuquerque, NM (United States)

    1993-05-01

    The successful design and testing of a three-phase planar integrated magnetic micromotor is presented. Fabrication is based on a modified deep X-ray lithography and electroplating or LIGA process. Maximum rotational speeds of 33,000 rpm are obtained in air with a rotor diameter of 285 {mu}m and do not change when operated in vacuum. Real time rotor response is obtained with an integrated shaft encoder. Long lifetime is evidenced by testing to over 5(10){sup 7} ration cycles without changes in performance. Projected speeds of the present motor configuration are in the vicinity of 100 krpm and are limited by torque ripple. Higher speeds, which are attractive for sensor applications. require constant torque characteristic excitation as is evidenced by ultracentrifuge and gyroscope design. Further understanding of electroplated magnetic material properties will drive these performance improvements.

  17. Performance Characterization of an xy-Stage Applied to Micrometric Laser Direct Writing Lithography

    Directory of Open Access Journals (Sweden)

    Juan Jaramillo

    2017-01-01

    Full Text Available This article concerns the characterization of the stability and performance of a motorized stage used in laser direct writing lithography. The system was built from commercial components and commanded by G-code. Measurements use a pseudo-periodic-pattern (PPP observed by a camera and image processing is based on Fourier transform and phase measurement methods. The results report that the built system has a stability against vibrations determined by peak-valley deviations of 65 nm and 26 nm in the x and y directions, respectively, with a standard deviation of 10 nm in both directions. When the xy-stage is in movement, it works with a resolution of 0.36 μm, which is an acceptable value for most of research and development (R and D microtechnology developments in which the typical feature size used is in the micrometer range.

  18. Performance Characterization of an xy-Stage Applied to Micrometric Laser Direct Writing Lithography

    Science.gov (United States)

    Jaramillo, Juan; Zarzycki, Artur; Galeano, July; Sandoz, Patrick

    2017-01-01

    This article concerns the characterization of the stability and performance of a motorized stage used in laser direct writing lithography. The system was built from commercial components and commanded by G-code. Measurements use a pseudo-periodic-pattern (PPP) observed by a camera and image processing is based on Fourier transform and phase measurement methods. The results report that the built system has a stability against vibrations determined by peak-valley deviations of 65 nm and 26 nm in the x and y directions, respectively, with a standard deviation of 10 nm in both directions. When the xy-stage is in movement, it works with a resolution of 0.36 µm, which is an acceptable value for most of research and development (R and D) microtechnology developments in which the typical feature size used is in the micrometer range. PMID:28146126

  19. Optimization of mask shot count using MB-MDP and lithography simulation

    Science.gov (United States)

    Chua, Gek Soon; Wang, Wei Long; Choi, Byoung IL; Zou, Yi; Tabery, Cyrus; Bork, Ingo; Nguyen, Tam; Fujimura, Aki

    2011-11-01

    In order to maintain manageable process windows, mask shapes at the 20nm technology node and below become so complex that mask write times reach 40 hours or might not be writeable at all since the extrapolated write time reaches 80 hours. The recently introduced Model Based Mask Data Preparation (MB-MDP) technique is able to reduce shot count and therefore mask write time by using overlapping shots. Depending on the amount of shot count reduction the contour of the mask shapes is changed leading to the question how the mask contour influences wafer performance. This paper investigates the tradeoff between mask shot count reduction using MB-MDP and wafer performance using lithography simulation. A typical Source-Mask-Optimization (SMO) result for a 20nm technology will be used as an example.

  20. Performance Characterization of an xy-Stage Applied to Micrometric Laser Direct Writing Lithography.

    Science.gov (United States)

    Jaramillo, Juan; Zarzycki, Artur; Galeano, July; Sandoz, Patrick

    2017-01-31

    This article concerns the characterization of the stability and performance of a motorized stage used in laser direct writing lithography. The system was built from commercial components and commanded by G-code. Measurements use a pseudo-periodic-pattern (PPP) observed by a camera and image processing is based on Fourier transform and phase measurement methods. The results report that the built system has a stability against vibrations determined by peak-valley deviations of 65 nm and 26 nm in the x and y directions, respectively, with a standard deviation of 10 nm in both directions. When the xy-stage is in movement, it works with a resolution of 0.36 μm, which is an acceptable value for most of research and development (R and D) microtechnology developments in which the typical feature size used is in the micrometer range.