WorldWideScience

Sample records for high baseline gating

  1. Gated integrator with signal baseline subtraction

    Science.gov (United States)

    Wang, Xucheng

    1996-01-01

    An ultrafast, high precision gated integrator includes an opamp having differential inputs. A signal to be integrated is applied to one of the differential inputs through a first input network, and a signal indicative of the DC offset component of the signal to be integrated is applied to the other of the differential inputs through a second input network. A pair of electronic switches in the first and second input networks define an integrating period when they are closed. The first and second input networks are substantially symmetrically constructed of matched components so that error components introduced by the electronic switches appear symmetrically in both input circuits and, hence, are nullified by the common mode rejection of the integrating opamp. The signal indicative of the DC offset component is provided by a sample and hold circuit actuated as the integrating period begins. The symmetrical configuration of the integrating circuit improves accuracy and speed by balancing out common mode errors, by permitting the use of high speed switching elements and high speed opamps and by permitting the use of a small integrating time constant. The sample and hold circuit substantially eliminates the error caused by the input signal baseline offset during a single integrating window.

  2. Gated integrator with signal baseline subtraction

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.

    1996-12-17

    An ultrafast, high precision gated integrator includes an opamp having differential inputs. A signal to be integrated is applied to one of the differential inputs through a first input network, and a signal indicative of the DC offset component of the signal to be integrated is applied to the other of the differential inputs through a second input network. A pair of electronic switches in the first and second input networks define an integrating period when they are closed. The first and second input networks are substantially symmetrically constructed of matched components so that error components introduced by the electronic switches appear symmetrically in both input circuits and, hence, are nullified by the common mode rejection of the integrating opamp. The signal indicative of the DC offset component is provided by a sample and hold circuit actuated as the integrating period begins. The symmetrical configuration of the integrating circuit improves accuracy and speed by balancing out common mode errors, by permitting the use of high speed switching elements and high speed opamps and by permitting the use of a small integrating time constant. The sample and hold circuit substantially eliminates the error caused by the input signal baseline offset during a single integrating window. 5 figs.

  3. High permittivity gate dielectric materials

    CERN Document Server

    2013-01-01

    "The book comprehensively covers all the current and the emerging areas of the physics and the technology of high permittivity gate dielectric materials, including, topics such as MOSFET basics and characteristics, hafnium-based gate dielectric materials, Hf-based gate dielectric processing, metal gate electrodes, flat-band and threshold voltage tuning, channel mobility, high-k gate stack degradation and reliability, lanthanide-based high-k gate stack materials, ternary hafnia and lanthania based high-k gate stack films, crystalline high-k oxides, high mobility substrates, and parameter extraction. Each chapter begins with the basics necessary for understanding the topic, followed by a comprehensive review of the literature, and ultimately graduating to the current status of the technology and our scientific understanding and the future prospects."

  4. High-Confidence Quantum Gate Tomography

    Science.gov (United States)

    Johnson, Blake; da Silva, Marcus; Ryan, Colm; Kimmel, Shelby; Donovan, Brian; Ohki, Thomas

    2014-03-01

    Debugging and verification of high-fidelity quantum gates requires the development of new tools and protocols to unwrap the performance of the gate from the rest of the sequence. Randomized benchmarking tomography[2] allows one to extract full information of the unital portion of the gate with high confidence. We report experimental confirmation of the technique's applicability to quantum gate tomography. We show that the method is robust to common experimental imperfections such as imperfect single-shot readout and state preparation. We also demonstrate the ability to characterize non-Clifford gates. To assist in the experimental implementation we introduce two techniques. ``Atomic Cliffords'' use phase ramping and frame tracking to allow single-pulse implementation of the full group of single-qubit Clifford gates. Domain specific pulse sequencers allow rapid implementation of the many thousands of sequences needed. This research was funded by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA), through the Army Research Office contract no. W911NF-10-1-0324.

  5. Dual-Gate p-GaN Gate High Electron Mobility Transistors for Steep Subthreshold Slope.

    Science.gov (United States)

    Bae, Jong-Ho; Lee, Jong-Ho

    2016-05-01

    A steep subthreshold slope characteristic is achieved through p-GaN gate HEMT with dual-gate structure. Obtained subthreshold slope is less than 120 μV/dec. Based on the measured and simulated data obtained from single-gate device, breakdown of parasitic floating-base bipolar transistor and floating gate charged with holes are responsible to increase abruptly in drain current. In the dual-gate device, on-current degrades with high temperature but subthreshold slope is not changed. To observe the switching speed of dual-gate device and transient response of drain current are measured. According to the transient responses of drain current, switching speed of the dual-gate device is about 10(-5) sec.

  6. Analysis and Design of Tri-Gate MOSFET with High Dielectrics Gate

    Directory of Open Access Journals (Sweden)

    Viranjay M. Srivastava

    2012-05-01

    Full Text Available The scaling of simple gate transistors requires the scaling and transistor elements like source/drain junction became difficult to scale further after a limit due to adverse effect of electrostatic and short-channel performance. The solution of the problem is tri-gate where we can increase the performance without increasing the width and without scaling. In this paper we have described the parameter of tri-gate and taking the high dielectric as substrate.

  7. Cleaning Challenges of High-κ/Metal Gate Structures

    KAUST Repository

    Hussain, Muhammad Mustafa

    2010-12-20

    High-κ/metal gates are used as transistors for advanced logic applications to improve speed and eliminate electrical issues associated with polySi and SiO2 gates. Various integration schemes are possible and will be discussed, such as dual gate, gate-first, and gate-last, both of which require specialized cleaning and etching steps. Specific areas of discussion will include cleaning and conditioning of the silicon surface, forming a high-quality chemical oxide, removal of the high-κ dielectric with selectivity to the SiO2 layer, cleaning and residue removal after etching, and prevention of galvanic corrosion during cleaning. © 2011 Scrivener Publishing LLC. All rights reserved.

  8. High fidelity quantum gates with vibrational qubits.

    Science.gov (United States)

    Berrios, Eduardo; Gruebele, Martin; Shyshlov, Dmytro; Wang, Lei; Babikov, Dmitri

    2012-11-26

    Physical implementation of quantum gates acting on qubits does not achieve a perfect fidelity of 1. The actual output qubit may not match the targeted output of the desired gate. According to theoretical estimates, intrinsic gate fidelities >99.99% are necessary so that error correction codes can be used to achieve perfect fidelity. Here we test what fidelity can be accomplished for a CNOT gate executed by a shaped ultrafast laser pulse interacting with vibrational states of the molecule SCCl(2). This molecule has been used as a test system for low-fidelity calculations before. To make our test more stringent, we include vibrational levels that do not encode the desired qubits but are close enough in energy to interfere with population transfer by the laser pulse. We use two complementary approaches: optimal control theory determines what the best possible pulse can do; a more constrained physical model calculates what an experiment likely can do. Optimal control theory finds pulses with fidelity >0.9999, in excess of the quantum error correction threshold with 8 × 10(4) iterations. On the other hand, the physical model achieves only 0.9992 after 8 × 10(4) iterations. Both calculations converge as an inverse power law toward unit fidelity after >10(2) iterations/generations. In principle, the fidelities necessary for quantum error correction are reachable with qubits encoded by molecular vibrations. In practice, it will be challenging with current laboratory instrumentation because of slow convergence past fidelities of 0.99.

  9. High-transconductance graphene solution-gated field effect transistors

    Science.gov (United States)

    Hess, L. H.; Hauf, M. V.; Seifert, M.; Speck, F.; Seyller, T.; Stutzmann, M.; Sharp, I. D.; Garrido, J. A.

    2011-07-01

    In this work, we report on the electronic properties of solution-gated field effect transistors (SGFETs) fabricated using large-area graphene. Devices prepared both with epitaxially grown graphene on SiC as well as with chemical vapor deposition grown graphene on Cu exhibit high transconductances, which are a consequence of the high mobility of charge carriers in graphene and the large capacitance at the graphene/water interface. The performance of graphene SGFETs, in terms of gate sensitivity, is compared to other SGFET technologies and found to be clearly superior, confirming the potential of graphene SGFETs for sensing applications in electrolytic environments.

  10. Gate-first integration of tunable work function metal gates of different thicknesses into high-k metal gates CMOS FinFETs for multi- VTh engineering

    KAUST Repository

    Hussain, Muhammad Mustafa

    2010-03-01

    Gate-first integration of tunable work function metal gates of different thicknesses (320 nm) into high-k/metal gates CMOS FinFETs was demonstrated to achieve multiple threshold voltages (VTh) for 32-nm technology and beyond logic, memory, input/output, and system-on-a-chip applications. The fabricated devices showed excellent short-channel effect immunity (drain-induced barrier lowering ∼ 40 mV/V), nearly symmetric VTh, low T inv(∼ 1.4 nm), and high Ion(∼780μAμm) for N/PMOS without any intentional strain enhancement. © 2006 IEEE.

  11. Ultra-high pressure water jet: Baseline report; Greenbook (chapter)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-31

    The ultra-high pressure waterjet technology was being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The ultra-high pressure waterjet technology acts as a cutting tool for the removal of surface substrates. The Husky{trademark} pump feeds water to a lance that directs the high pressure water at the surface to be removed. The technologies being tested for concrete decontamination are targeted for alpha contamination. The safety and health evaluation during the human factors assessment focused on two main areas: noise and dust.

  12. Challenges in Atomic-Scale Characterization of High-k Dielectrics and Metal Gate Electrodes for Advanced CMOS Gate Stacks

    Institute of Scientific and Technical Information of China (English)

    Xinhua Zhu; Jianmin Zhu; Aidong Li; Zhiguo Liu; Naiben Ming

    2009-01-01

    The decreasing feature sizes in complementary metal-oxide semiconductor (CMOS) transistor technology will require the replacement of SiO2 with gate dielectrics that have a high dielectric constant (high-k) because as the SiO2 gate thickness is reduced below 1.4 nm, electron tunnelling effects and high leakage currents occur in SiO2, which present serious obstacles to future device reliability.In recent years significant progress has been made on the screening and selection of high-k gate dielectrics, understanding their physical properties, and their integration into CMOS technology.Now the family of hafnium oxide-based materials has emerged as the leading candidate for high-k gate dielectrics due to their excellent physical properties.It is also realized that the high-k oxides must be implemented in conjunction with metal gate electrodes to get sufficient potential for CMOS continue scaling.In the advanced nanoscale Si-based CMOS devices, the composition and thickness of interfacial layers in the gate stacks determine the critical performance of devices.Therefore, detailed atomicscale understandings of the microstructures and interfacial structures built in the advanced CMOS gate stacks,are highly required.In this paper, several high-resolution electron, ion, and photon-based techniques currently used to characterize the high-k gate dielectrics and interfaces at atomic-scale, are reviewed.Particularly, we critically review the research progress on the characterization of interface behavior and structural evolution in the high-k gate dielectrics by high-resolution transmission electron microscopy (HRTEM) and the related techniques based on scanning transmission electron microscopy (STEM), including high-angle annular darkfield (HAADF) imaging (also known as Z-contrast imaging), electron energy-loss spectroscopy (EELS), and energy dispersive X-ray spectroscopy (EDS), due to that HRTEM and STEM have become essential metrology tools for characterizing the dielectric

  13. Ultra-high pressure water jet: Baseline report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-31

    The ultra-high pressure waterjet technology was being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The ultra-high pressure waterjet technology acts as a cutting tool for the removal of surface substrates. The Husky{trademark} pump feeds water to a lance that directs the high pressure water at the surface to be removed. The safety and health evaluation during the testing demonstration focused on two main areas of exposure. These were dust and noise. The dust exposure was found to be minimal, which would be expected due to the wet environment inherent in the technology, but noise exposure was at a significant level. Further testing for noise is recommended because of the outdoor environment where the testing demonstration took place. In addition, other areas of concern found were arm-hand vibration, ergonomics, heat stress, tripping hazards, electrical hazards, lockout/tagout, fall hazards, slipping hazards, hazards associated with the high pressure water, and hazards associated with air pressure systems.

  14. Semiconductor optical amplifier-based all-optical gates for high-speed optical processing

    DEFF Research Database (Denmark)

    Stubkjær, Kristian

    2000-01-01

    Semiconductor optical amplifiers are useful building blocks for all-optical gates as wavelength converters and OTDM demultiplexers. The paper reviews the progress from simple gates using cross-gain modulation and four-wave mixing to the integrated interferometric gates using cross-phase modulation....... These gates are very efficient for high-speed signal processing and open up interesting new areas, such as all-optical regeneration and high-speed all-optical logic functions...

  15. Side-gate modulation effects on high-quality BN-Graphene-BN nanoribbon capacitors

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yang; Chen, Xiaolong; Ye, Weiguang; Wu, Zefei; Han, Yu; Han, Tianyi; He, Yuheng; Cai, Yuan; Wang, Ning, E-mail: phwang@ust.hk [Department of Physics and the William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China)

    2014-12-15

    High-quality BN-Graphene-BN nanoribbon capacitors with double side-gates of graphene have been experimentally realized. The double side-gates can effectively modulate the electronic properties of graphene nanoribbon capacitors. By applying anti-symmetric side-gate voltages, we observed significant upward shifting and flattening of the V-shaped capacitance curve near the charge neutrality point. Symmetric side-gate voltages, however, only resulted in tilted upward shifting along the opposite direction of applied gate voltages. These modulation effects followed the behavior of graphene nanoribbons predicted theoretically for metallic side-gate modulation. The negative quantum capacitance phenomenon predicted by numerical simulations for graphene nanoribbons modulated by graphene side-gates was not observed, possibly due to the weakened interactions between the graphene nanoribbon and side-gate electrodes caused by the Ga{sup +} beam etching process.

  16. High-performance graphene photodetector by interfacial gating

    CERN Document Server

    Guo, Xitao; Nan, Haiyan; Yu, Yuanfang; Jiang, Jie; Zhao, Weiwei; Li, Jinhuan; Zafar, Zainab; Xiang, Nan; Ni, Zhonghua; Hu, Weida; You, Yumeng; Ni, Zhenhua

    2016-01-01

    Graphene based photo-detecting has received great attentions and the performance of such detector is stretching to both ends of high sensitivity and ultra-fast response. However, limited by the current photo-gating mechanism, the price for achieving ultra-high sensitivity is sacrificing the response time. Detecting weak signal within short response time is crucial especially in applications such as optical positioning, remote sensing, and biomedical imaging. In this work, we bridge the gap between ultra-fast response and ultra-high sensitivity by employing a graphene/SiO2/lightly-doped-Si architecture with revolutionary interfacial gating mechanism. Such device is capable to detect < 1 nW signal (with responsivity of ~1000 A W-1) and the spectral response extends from visible to near-infrared. More importantly, the photoresponse time of our device has been pushed to ~400 ns. The current device structure does not need complicated fabrication process and is fully compatible with the silicon technology. This ...

  17. 湖北武汉中盖艾滋病项目三类高危人群基线调查分析%Baseline investigation on three kinds of high risk population in Wuhan,China-Bill & Melinda Gates Foundation AIDS program

    Institute of Scientific and Technical Information of China (English)

    刘聪; 许骏; 周旺; 杨连第; 姚中兆; 王夏; 王红方; 刘普林

    2011-01-01

    Objective To investigate the baseline information of three kinds of high risk population (FSW, DU, MSM),and provide suggestion to establish strategy for the control program. Methods According to the guideline of UNAIDS/WHO/FHI, three kinds of high risk population were investigated, including: size-estimation of the three kinds of high risk population, AIDS related behavior, serology examination, and service-acceptability etc. Results The cumulative number of HIV/AIDS cases reported of the three kinds was: opposite sex contact (37. 69% ), drug-injection (27. 24% ) and homogeneous sexual transmission ( 5. 97% ). The three kinds of people were of a certain size and spread in different places. The awareness rate of AIDS knowledge of the DU, FSW, MSM was 80. 9%, 69.7%, 90. 4%, respectively. The acceptable rate of HIV antibody test was 55. 22%, 26. 62%, 28.50%, respectively. The MSM's HIV infection rate was 5.04%, syphilis infection rate was 21.49%. The rate of condom use of FSW and MSM in recent month was 73.42%,45.45%, respectively. The rate of needle-sharing of DU in recent six months was 66. 70%. Conclusions The three kinds of high risk population had a large size, they had a great proportion in the HIV transmission-constitute as well. However, the acoeptable rate of HIV antibody test was rather low. The high-risk behavior proportion was also high, and the MSM's HIV infection rate was in particular high. Therefore, there is great difficulty in AIDS control. It is necessary to form a “three-in-one” pattern, to strengthen the intervention for the high risk population and the management for HIV antibody positive cases, so as to contain the spread of AIDS.%目的 了解三类高危人群的基线情况,为制定中盖项目策略和计划提供参考.方法 按照UNAIDS/WHO/FHI有关指南的方法,进行三类高危人群的规模估计、艾滋病相关行为学调查、血清学检测、接受性病服务情况等.结果 累计报告HIV

  18. Mixed-Species Logic Gates and High-Fidelity Universal Gate Set for Trapped-Ion Qubits

    Science.gov (United States)

    Tan, Ting Rei

    2016-05-01

    Precision control over hybrid physical systems at the quantum level is important for the realization of many quantum-based technologies. For trapped-ions, a hybrid system formed of different species introduces extra degrees of freedom that can be exploited to expand and refine the control of the system. We demonstrate an entangling gate between two atomic ions of different elements that can serve as an important building block of quantum information processing (QIP), quantum networking, precision spectroscopy, metrology, and quantum simulation. An entangling geometric phase gate between a 9 Be+ ion and a 25 Mg+ ion is realized through an effective spin-spin interaction generated by state-dependent forces. A mixed-species Bell state is thereby created with a fidelity of 0 . 979(1) . We use the gate to construct a SWAP gate that interchanges the quantum states of the two dissimilar qubits. We also report a high-fidelity universal gate set for 9 Be+ ion qubits, achieved through a combination of improved laser beam quality and control, improved state preparation, and reduced electric potential noise on trap electrodes. Supported by Office of the Director of National Intelligence (ODNI) Intelligence Advanced Research Projects Activity (IARPA), ONR, and the NIST Quantum Information Program.

  19. Scanner baseliner monitoring and control in high volume manufacturing

    Science.gov (United States)

    Samudrala, Pavan; Chung, Woong Jae; Aung, Nyan; Subramany, Lokesh; Gao, Haiyong; Gomez, Juan-Manuel

    2016-03-01

    We analyze performance of different customized models on baseliner overlay data and demonstrate the reduction in overlay residuals by ~10%. Smart Sampling sets were assessed and compared with the full wafer measurements. We found that performance of the grid can still be maintained by going to one-third of total sampling points, while reducing metrology time by 60%. We also demonstrate the feasibility of achieving time to time matching using scanner fleet manager and thus identify the tool drifts even when the tool monitoring controls are within spec limits. We also explore the scanner feedback constant variation with illumination sources.

  20. Gate controlled high efficiency ballistic energy conversion system

    NARCIS (Netherlands)

    Xie, Yanbo; Bos, Diederik; de Boer, Hans L.; van den Berg, Albert; Eijkel, Jan C.T.; Zengerle, R.

    2013-01-01

    Last year we demonstrated the microjet ballistic energy conversion system[1]. Here we show that the efficiency of such a system can be further improved by gate control. With gate control the electrical current generation is enhanced a hundred times with respect to the current generated from the zeta

  1. High-Sensitivity, Highly Transparent, Gel-Gated MoS2 Phototransistor on Biodegradable Nanopaper

    KAUST Repository

    Zhang, Qing

    2016-06-21

    Transition metal dichalcogenides hold great promise for a variety of novel electrical, optical and mechanical devices and applications. Among them, molybdenum disulphide (MoS2) is gaining increasing attention as the gate dielectric and semiconductive channel for high-perfomance field effect transistors. Here we report on the first MoS2 phototransistor built on flexible, transparent and biodegradable substrate with electrolyte gate dielectric. We have carried out systematic studies on its electrical and optoelectronic properties. The MoS2 phototransistor exhibited excellent photo responsivity of ~1.5 kA/W, about two times higher compared to typical back-gated devices reported in previous studies. The device is highly transparent at the same time with an average optical transmittance of 82%. Successful fabrication of phototransistors on flexible cellulose nanopaper with excellent performance and transparency suggests that it is feasible to achieve an ecofriendly, biodegradable phototransistor with great photoresponsivity, broad spectral range and durable flexibility.

  2. Baseline high heat flux and plasma facing materials for fusion

    Science.gov (United States)

    Ueda, Y.; Schmid, K.; Balden, M.; Coenen, J. W.; Loewenhoff, Th.; Ito, A.; Hasegawa, A.; Hardie, C.; Porton, M.; Gilbert, M.

    2017-09-01

    In fusion reactors, surfaces of plasma facing components (PFCs) are exposed to high heat and particle flux. Tungsten and Copper alloys are primary candidates for plasma facing materials (PFMs) and coolant tube materials, respectively, mainly due to high thermal conductivity and, in the case of tungsten, its high melting point. In this paper, recent understandings and future issues on responses of tungsten and Cu alloys to fusion environments (high particle flux (including T and He), high heat flux, and high neutron doses) are reviewed. This review paper includes; Tritium retention in tungsten (K. Schmid and M. Balden), Impact of stationary and transient heat loads on tungsten (J.W. Coenen and Th. Loewenhoff), Helium effects on surface morphology of tungsten (Y. Ueda and A. Ito), Neutron radiation effects in tungsten (A. Hasegawa), and Copper and copper alloys development for high heat flux components (C. Hardie, M. Porton, and M. Gilbert).

  3. High Accuracy and Real-Time Gated Viewing Laser Radar

    Institute of Scientific and Technical Information of China (English)

    Dong Li; Hua-Jun Yang; Shan-Pei Zhou

    2011-01-01

    A gated viewing laser radar has an excellent performance in underwater low light level imaging,and it also provides a viable solution to inhibit backscattering.In this paper,a gated viewing imaging system according to the demand for real-time imaging is presented,and then the simulation is used to analyze the performance of the real-time gated viewing system.The range accuracy performance is limited by the slice number,the width of gate,the delay time step,the initial delay time,as well as the system noise and atmospheric turbulence.The simulation results indicate that the highest range accuracy can be achieved when the system works with the optimal parameters.Finally,how to choose the optimal parameters has been researched.

  4. Extraction of bulk generation lifetime and surface generation velocity in high-resistivity silicon by means of gated diodes

    CERN Document Server

    Verzellesi, G; Bosisio, L; Dalla Betta, Gian Franco; Pignatel, Giogrio Umberto

    2002-01-01

    We show that the accuracy of the gated diode method for measuring bulk generation lifetime and surface generation velocity in high resistivity silicon depends critically on the gate length of the test device, as a result of nonidealities affecting the gated diode operation. Minimization of the surface generation velocity measurement error requires the gate length to be suitably decreased, while long gate length structures are needed for accurate bulk generation lifetime extraction.

  5. Gated viewing and high-accuracy three-dimensional laser radar

    DEFF Research Database (Denmark)

    Busck, Jens; Heiselberg, Henning

    2004-01-01

    We have developed a fast and high-accuracy three-dimensional (3-D) imaging laser radar that can achieve better than 1 mm range accuracy for half a million pixels in less than 1 s. Our technique is based on range-gating segmentation. We combine the advantages of gated viewing with our new fast...

  6. Gated viewing and high-accuracy three-dimensional laser radar

    DEFF Research Database (Denmark)

    Busck, Jens; Heiselberg, Henning

    2004-01-01

    We have developed a fast and high-accuracy three-dimensional (3-D) imaging laser radar that can achieve better than 1 mm range accuracy for half a million pixels in less than 1 s. Our technique is based on range-gating segmentation. We combine the advantages of gated viewing with our new fast...

  7. Baseline Concept Description of a Small Modular High Temperature Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Gougar, Hans D. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-10-01

    The objective of this report is to provide a description of generic small modular high temperature reactors (herein denoted as an smHTR), summarize their distinguishing attributes, and lay out the research and development (R&D) required for commercialization. The generic concepts rely heavily on the modular high temperature gas-cooled reactor designs developed in the 1980s which were never built but for which pre-licensing or certification activities were conducted. The concept matured more recently under the Next Generation Nuclear Plant (NGNP) project, specifically in the areas of fuel and material qualification, methods development, and licensing. As all vendor-specific designs proposed under NGNP were all both ‘small’ or medium-sized and ‘modular’ by International Atomic Energy Agency (IAEA) and Department of Energy (DOE) standards, the technical attributes, challenges, and R&D needs identified, addressed, and documented under NGNP are valid and appropriate in the context of Small Modular Reactor (SMR) applications. Although the term High Temperature Reactor (HTR) is commonly used to denote graphite-moderated, thermal spectrum reactors with coolant temperatures in excess of 650oC at the core outlet, in this report the historical term High Temperature Gas-Cooled Reactor (HTGR) will be used to distinguish the gas-cooled technology described herein from its liquid salt-cooled cousin. Moreover, in this report it is to be understood that the outlet temperature of the helium in an HTGR has an upper limit of 950 degrees C which corresponds to the temperature to which certain alloys are currently being qualified under DOE’s ARC program. Although similar to the HTGR in just about every respect, the Very High Temperature Reactor (VHTR) may have an outlet temperature in excess of 950 degrees C and is therefore farther from commercialization because of the challenges posed to materials exposed to these temperatures. The VHTR is the focus of R&D under the

  8. Baseline Concept Description of a Small Modular High Temperature Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Hans Gougar

    2014-05-01

    The objective of this report is to provide a description of generic small modular high temperature reactors (herein denoted as an smHTR), summarize their distinguishing attributes, and lay out the research and development (R&D) required for commercialization. The generic concepts rely heavily on the modular high temperature gas-cooled reactor designs developed in the 1980s which were never built but for which pre-licensing or certification activities were conducted. The concept matured more recently under the Next Generation Nuclear Plant (NGNP) project, specifically in the areas of fuel and material qualification, methods development, and licensing. As all vendor-specific designs proposed under NGNP were all both ‘small’ or medium-sized and ‘modular’ by International Atomic Energy Agency (IAEA) and Department of Energy (DOE) standards, the technical attributes, challenges, and R&D needs identified, addressed, and documented under NGNP are valid and appropriate in the context of Small Modular Reactor (SMR) applications. Although the term High Temperature Reactor (HTR) is commonly used to denote graphite-moderated, thermal spectrum reactors with coolant temperatures in excess of 650oC at the core outlet, in this report the historical term High Temperature Gas-Cooled Reactor (HTGR) will be used to distinguish the gas-cooled technology described herein from its liquid salt-cooled cousin. Moreover, in this report it is to be understood that the outlet temperature of the helium in an HTGR has an upper limit of 950 degrees C which corresponds to the temperature to which certain alloys are currently being qualified under DOE’s ARC program. Although similar to the HTGR in just about every respect, the Very High Temperature Reactor (VHTR) may have an outlet temperature in excess of 950 degrees C and is therefore farther from commercialization because of the challenges posed to materials exposed to these temperatures. The VHTR is the focus of R&D under the

  9. Current Progress of Hf (Zr)-Based High-k Gate Dielectric Thin Films

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    With the continued downscaling of complementary metal-oxide-semiconductor field effect transistor dimensions, high-dielectric constant (high-k) gate materials, as alternatives to SiO2, have been extensively investigated. Hf (Zr)-based high-k gate dielectric thin films have been regarded as the most promising candidates for high-k gate dielectric according to the International Technology Roadmap for Semiconductor due to their excellent physical properties and performance. This paper reviews the recent progress on Hf (Zr)-based high-k gate dielectrics based on PVD (physical vapor deposition) process. This article begins with a survey of various methods developed for generating Hf (Zr)-based high-k gate dielectrics, and then mainly focuses on microstructure, synthesis, characterization, formation mechanisms of interfacial layer, and optical properties of Hf (Zr)-based high-k gate dielectrics. Finally, this review concludes with personal perspectives towards future research on Hf (Zr)-based high-k gate dielectrics.

  10. Compensated readout for high-density MOS-gated memristor crossbar array

    KAUST Repository

    Zidan, Mohammed A.

    2015-01-01

    Leakage current is one of the main challenges facing high-density MOS-gated memristor arrays. In this study, we show that leakage current ruins the memory readout process for high-density arrays, and analyze the tradeoff between the array density and its power consumption. We propose a novel readout technique and its underlying circuitry, which is able to compensate for the transistor leakage-current effect in the high-density gated memristor array.

  11. Demonstration of large field effect in topological insulator films via a high-κ back gate

    Science.gov (United States)

    Wang, C. Y.; Lin, H. Y.; Yang, S. R.; Chen, K. H. M.; Lin, Y. H.; Chen, K. H.; Young, L. B.; Cheng, C. K.; Fanchiang, Y. T.; Tseng, S. C.; Hong, M.; Kwo, J.

    2016-05-01

    The spintronics applications long anticipated for topological insulators (TIs) has been hampered due to the presence of high density intrinsic defects in the bulk states. In this work we demonstrate the back-gating effect on TIs by integrating Bi2Se3 films 6-10 quintuple layer (QL) thick with amorphous high-κ oxides of Al2O3 and Y2O3. Large gating effect of tuning the Fermi level EF to very close to the band gap was observed, with an applied bias of an order of magnitude smaller than those of the SiO2 back gate, and the modulation of film resistance can reach as high as 1200%. The dependence of the gating effect on the TI film thickness was investigated, and ΔN2D/ΔVg varies with TI film thickness as ˜t-0.75. To enhance the gating effect, a Y2O3 layer thickness 4 nm was inserted into Al2O3 gate stack to increase the total κ value to 13.2. A 1.4 times stronger gating effect is observed, and the increment of induced carrier numbers is in good agreement with additional charges accumulated in the higher κ oxides. Moreover, we have reduced the intrinsic carrier concentration in the TI film by doping Te to Bi2Se3 to form Bi2TexSe1-x. The observation of a mixed state of ambipolar field that both electrons and holes are present indicates that we have tuned the EF very close to the Dirac Point. These results have demonstrated that our capability of gating TIs with high-κ back gate to pave the way to spin devices of tunable EF for dissipationless spintronics based on well-established semiconductor technology.

  12. High-performance SEGISFET pH Sensor using the structure of double-gate a-IGZO TFTs with engineered gate oxides

    Science.gov (United States)

    Pyo, Ju-Young; Cho, Won-Ju

    2017-03-01

    In this paper, we propose a high-performance separative extended gate ion-sensitive field-effect transistor (SEGISFET) that consists of a tin dioxide (SnO2) SEG sensing part and a double-gate structure amorphous indium gallium zinc oxide (a-IGZO) thin-film transistor (TFT) with tantalum pentoxide/silicon dioxide (Ta2O5/SiO2)-engineered top-gate oxide. To increase sensitivity, we maximized the capacitive coupling ratio by applying high-k dielectric at the top-gate oxide layer. As an engineered top-gate oxide, a stack of 25 nm-thick Ta2O5 and 10 nm-thick SiO2 layers was found to simultaneously satisfy a small equivalent oxide thickness (˜17.14 nm), a low leakage current, and a stable interfacial property. The threshold-voltage instability, which is a fundamental issue in a-IGZO TFTs, was improved by low-temperature post-deposition annealing (˜87 °C) using microwave irradiation. The double-gate structure a-IGZO TFTs with engineered top-gate oxide exhibited high mobility, small subthreshold swing, high drive current, and larger on/off current ratio. The a-IGZO SEGISFETs with a dual-gate sensing mode showed a pH sensitivity of 649.04 mV pH-1, which is far beyond the Nernst limit. The non-ideal behavior of ISFETs, hysteresis, and drift effect also improved. These results show that the double-gate structure a-IGZO TFTs with engineered top-gate oxide can be a good candidate for cheap and disposable SEGISFET sensors.

  13. Carbon Nanotube Field Emission Devices With Integrated Gate for High Current Applications

    Science.gov (United States)

    2008-08-01

    exhibits an edge effect and in fact, shows a slight enhancement. A baseline structure, consisting of two parallel plates with the same applied field and...electrostatics the addition of the gate electrode will not reduce the edge effect for the CNT pillars. As a result of this it is expected that the voltage...field emission from an individual aligned carbon nanotube bundle enhanced by edge effect ", Appl. Phys. Lett., 90, 153108, 2007. [6] Killian, J. L

  14. Natural radioactivity consideration for high- dielectrics and metal gates choice in nanoelectronic devices

    OpenAIRE

    Gedion, Michael; Wrobel, Frédéric; Saigné, Frédéric

    2010-01-01

    Abstract In order to face downscaling, new chemical elements are used and suggested for the semiconductor industry. However, some of these elements have natural radioactive isotopes, which may cause reliability issues in nanoelectronic devices by triggering soft errors. In this paper, we focus on high-? dielectric materials and metal gates. We show that beside physical, chemical and mechanical properties of high-? dielectrics and metal gates, natural radioactivity is also a crucial propert...

  15. Characteristics of high-quality HfSiON gate dielectric prepared by physical vapour deposition

    Institute of Scientific and Technical Information of China (English)

    Xu Gao-Bo; Xu Qiu-Xia

    2009-01-01

    This paper presents a method using simple physical vapour deposition to form high-quality hafnium silicon oxyni-tride (HfSiON) on ultrathin SiO2 buffer layer. The gate dielectric with 10A (1/A = 0.1 nm) equivalent oxide thickness is obtained. The experimental results indicate that the prepared HfSiON gate dielectric exhibits good physical and electrical characteristics, including very good thermal stability up to 1000℃, excellent interface properties, high dielec-tric constant (k = 14) and low gate-leakage current (Ig= 1.9×10-3 A/cm2@Vg = Vfb-1V for EOT of 10A). TaN metal gate electrode is integrated with the HfSiON gate dielectric.The effective work function of TaN on HfSiON is 4.3eV, meeting the requirements of NMOS for the metal gate. And, the impacts of sputtering ambient and annealing temperature on the electrical properties of HfSiON gate dielectric are investigated.

  16. Compact analytical model for single gate AlInSb/InSb high electron mobility transistors

    Institute of Scientific and Technical Information of China (English)

    S.Theodore Chandra; N.B.Balamurugan; G.Subalakshmi; T.Shalini; G.Lakshmi Priya

    2014-01-01

    We have developed a 2D analytical model for the single gate AlInSb/InSb HEMT device by solving the Poisson equation using the parabolic approximation method.The developed model analyses the device performance by calculating the parameters such as surface potential,electric field distribution and drain current.The high mobility of the AlInSb/InSb quantum makes this HEMT ideal for high frequency,high power applications.The working of the single gate AlInSb/InSb HEMT device is studied by considering the variation of gate source voltage,drain source voltage,and channel length under the gate region and temperature.The carrier transport efficiency is improved by uniform electric field along the channel and the peak values near the source and drain regions.The results from the analytical model are compared with that of numerical simulations (TCAD) and a good agreement between them is achieved.

  17. The effect of acute exogenous melatonin on P50 suppression in healthy male volunteers stratified for low and high gating levels

    DEFF Research Database (Denmark)

    Ucar, Ebru; Lehtinen, Emilia K; Glenthøj, Birte Y

    2012-01-01

    Sensory gating is frequently found to be disturbed in patients with schizophrenia. In addition, a disruption of the circadian rhythm together with a low nocturnal melatonin output is regularly found in these patients. Since there is some evidence that a brief period of sleep normalizes sensory...... gating in schizophrenia patients, it is conceivable that their disrupted melatonin level may contribute to the deficits in P50 suppression. In this initial study, the effects of acutely administered melatonin on sensory gating in healthy subjects were investigated. In a double-blind placebo......-controlled crossover design, 21 healthy male volunteers were administered melatonin (4 mg) or placebo, after which they were tested in a P50 suppression paradigm. In the group as a whole, melatonin did not affect P50 suppression. However, melatonin increased the P50 ratio in the individuals with high baseline...

  18. Optimal Control of High-Fidelity Quantum Gates in the Presence of Decoherence

    CERN Document Server

    Grace, M; Kosut, R; Lidar, D A; Rabitz, H; Walmsley, I; Brif, Constantin; Grace, Matthew; Kosut, Robert; Lidar, Daniel A.; Rabitz, Herschel; Walmsley, Ian

    2006-01-01

    This work studies the feasibility of optimal control of high-fidelity quantum gates in a model of interacting two-level particles. One set of particles serves as the quantum information processor, whose evolution is controlled by a time-dependent external field. The other particles are not directly controlled and serve as an effective environment, coupling to which is the source of decoherence. The control objective is to generate target one- and two-qubit gates in the presence of strong environmentally-induced decoherence and physically motivated restrictions on the control field. The quantum-gate fidelity, expressed in terms of a state-independent distance measure, is maximized with respect to the control field using combined genetic and gradient algorithms. The resulting high-fidelity gates demonstrate the utility of optimal control for precise management of quantum dynamics, especially when the system complexity is exacerbated by environmental coupling.

  19. Optically-gated Non-latched High Gain Power Device

    Science.gov (United States)

    2008-11-21

    INTENSITY MODULATION OF PSD SWITCHING DYNAMICS 39 5.1. Optically-modulated Active Gate Control (OMAG) architecture for full controllability of turn-on... architecture for next- generation avionics, electromagnetic interference (EMI) is a critical issue [2, 3]. EMI immunity of these actuators from external jamming...TlissMT (o] Ns * I utut*n I/a^l Rh-( J.52«5E»84 [ mVC ] I 0«| 1.20S2JE-02 [I/O cm] aloha =| 07t627 Ml: Bulk concenfcation M • Mobility O ! Bull

  20. Highly tunable local gate controlled complementary graphene device performing as inverter and voltage controlled resistor.

    Science.gov (United States)

    Kim, Wonjae; Riikonen, Juha; Li, Changfeng; Chen, Ya; Lipsanen, Harri

    2013-10-04

    Using single-layer CVD graphene, a complementary field effect transistor (FET) device is fabricated on the top of separated back-gates. The local back-gate control of the transistors, which operate with low bias at room temperature, enables highly tunable device characteristics due to separate control over electrostatic doping of the channels. Local back-gating allows control of the doping level independently of the supply voltage, which enables device operation with very low VDD. Controllable characteristics also allow the compensation of variation in the unintentional doping typically observed in CVD graphene. Moreover, both p-n and n-p configurations of FETs can be achieved by electrostatic doping using the local back-gate. Therefore, the device operation can also be switched from inverter to voltage controlled resistor, opening new possibilities in using graphene in logic circuitry.

  1. Gate-Defined Quantum Devices Realized in InGaAs/InP by Incorporating a High-κ Layer as Gate Dielectric

    Science.gov (United States)

    Sun, Jie; Larsson, Marcus; Xu, H. Q.

    2011-12-01

    Single and double quantum dot devices are realized in InGaAs/InP heterostructures by top gating technology with incorporated High-κ HfO2 gate dielectric layers. At 300 mK, Coulomb blockade effects are observed in as-fabricated devices, and the charge states can be measured by the integrated quantum point contacts. The developed technology should stimulate the research on quantum devices made from materials to which the gating technology is often difficult to apply due to low Schottky barrier height.

  2. GaN High-Electron-Mobility Transistor with WN x /Cu Gate for High-Power Applications

    Science.gov (United States)

    Hsieh, Ting-En; Lin, Yueh-Chin; Li, Fang-Ming; Shi, Wang-Cheng; Huang, Yu-Xiang; Lan, Wei-Cheng; Chin, Ping-Chieh; Chang, Edward Yi

    2015-12-01

    A GaN high-electron-mobility transistor (HEMT) with WN x /Cu gate for high-power applications has been investigated. The direct-current (DC) characteristics of the device are comparable to those of conventional Ni/Au-gated GaN HEMTs. The results of high-voltage stress testing indicate that the device is stable after application of 200 V stress for 42 h. The WN x /Cu-gated GaN HEMT exhibited no obvious changes in the DC characteristics or Schottky barrier height before and after annealing at 250°C for 1 h. These results demonstrate that the WN x /Cu gate structure can be used in a GaN HEMT for high-power applications with good thermal stability.

  3. Analytical model including the fringing-induced barrier lowering effect for a dual-material surrounding-gate MOSFET with a high-K gate dielectric

    Institute of Scientific and Technical Information of China (English)

    Li Cong; Zhuang Yi-Qi; Zhang Li; Bao Jun-Lin

    2012-01-01

    By solving Poisson's equation in both semiconductor and gate insulator regions in the cylindrical coordinates,an analytical model for a dual-material surrounding-gate (DMSG) metal-oxide semiconductor field-effect transistor (MOSFET) with a highgate dielectric has been developed.Using the derived model,the influences of fringing-induced barrier lowering (FIBL) on surface potential,subthreshold current,DIBL,and subthreshold swing are investigated.It is found that for the same equivalent oxide thickness,the gate insulator with high-κ dielectric degrades the short-channel performance of the DMSG MOSFET.The accuracy of the analytical model is verified by the good agreement of its results with that obtained from the ISE three-dimensional numerical device simulator.

  4. Effects of High-k Dielectrics with Metal Gate for Electrical Characteristics of SOI TRI-GATE FinFET Transistor

    Directory of Open Access Journals (Sweden)

    Fatima Zohra Rahou

    2016-11-01

    Full Text Available The implementation of high-k gate dielectrics is one of several strategies developed to allow further miniaturization of microelectronic components. From the simulation result; it was shown that HfO2 is the best dielectric material with metal gate TiN, which giving better subthreshold swing (SS, drain-induced barrier lowing (DIBL, leakage current Ioff and Ion/Ioff ratio.

  5. High dielectric constant materials and their application to IC gate stack systems

    Institute of Scientific and Technical Information of China (English)

    TU; Hailing

    2005-01-01

    High dielectric constant (high-k) materials are vital tothe nanoelectronic devices.The paper reviews research development of high-k materials, describes a variety of manufacture technologies and discusses the application of the gate stack systems to non-classical device structures.

  6. High performance top-gated indium–zinc–oxide thin film transistors with in-situ formed HfO{sub 2} gate insulator

    Energy Technology Data Exchange (ETDEWEB)

    Song, Yang, E-mail: yang_song@brown.edu [Department of Physics, Brown University, 182 Hope Street, Providence, RI 02912 (United States); Zaslavsky, A. [Department of Physics, Brown University, 182 Hope Street, Providence, RI 02912 (United States); School of Engineering, Brown University, 184 Hope Street, Providence, RI 02912 (United States); Paine, D.C. [School of Engineering, Brown University, 184 Hope Street, Providence, RI 02912 (United States)

    2016-09-01

    We report on top-gated indium–zinc–oxide (IZO) thin film transistors (TFTs) with an in-situ formed HfO{sub 2} gate dielectric insulator. Building on our previous demonstration of high-performance IZO TFTs with Al{sub 2}O{sub 3}/HfO{sub 2} gate dielectric, we now report on a one-step process, in which Hf is evaporated onto the 20 nm thick IZO channel, forming a partially oxidized HfO{sub x} layer, without any additional insulator in-between. After annealing in air at 300 °C, the in-situ reaction between partially oxidized Hf and IZO forms a high quality HfO{sub 2} gate insulator with a low interface trapped charge density N{sub TC} ~ 2.3 × 10{sup 11} cm{sup −2} and acceptably low gate leakage < 3 × 10{sup −7} A/cm{sup 2} at gate voltage V{sub G} = 1 V. The annealed TFTs with gate length L{sub G} = 50 μm have high mobility ~ 95 cm{sup 2}/V ∙ s (determined via the Y-function technique), high on/off ratio ~ 10{sup 7}, near-zero threshold voltage V{sub T} = − 0.02 V, and a subthreshold swing of 0.062 V/decade, near the theoretical limit. The on-current of our proof-of-concept TFTs is relatively low, but can be improved by reducing L{sub G}, indicating that high-performance top-gated HfO{sub 2}-isolated IZO TFTs can be fabricated using a single-step in-situ dielectric formation approach. - Highlights: • High-performance indium–zinc–oxide (IZO) thin film transistors (TFTs). • Single-step in-situ dielectric formation approach simplifies fabrication process. • During anneal, reaction between HfO{sub x} and IZO channel forms a high quality HfO{sub 2} layer. • Gate insulator HfO{sub 2} shows low interface trapped charge and small gate leakage. • TFTs have high mobility, near-zero threshold voltage, and a low subthreshold swing.

  7. Fabrication and characterization of V-gate AlGaN/GaN high-electron-mobility transistors

    Institute of Scientific and Technical Information of China (English)

    Zhang Kai; Cao Meng-Yi; Chen Yong-He; Yang Li-Yuan; Wang Chong; Ma Xiao-Hua; Hao Yue

    2013-01-01

    V-gate GaN high-electron-mobility transistors (HEMTs) are fabricated and investigated systematically.A V-shaped recess geometry is obtained using an improved Si3N4 recess etching technology.Compared with standard HEMTs,the fabricated V-gate HEMTs exhibit a 17% higher peak extrinsic transconductance due to a narrowed gate foot.Moreover,both the gate leakage and current dispersion are dramatically suppressed simultaneously,although a slight degradation of frequency response is observed.Based on a two-dimensional electric field simulation using Silvaco "ATLAS" for both standard HEMTs and V-gate HEMTs,the relaxation in peak electric field at the gate edge is identified as the predominant factor leading to the superior performance of V-gate HEMTs.

  8. Fabrication and characteristics of high-K HfO2 gate dielectrics on n-germanium

    Institute of Scientific and Technical Information of China (English)

    Han De-Dong; Kang Jin-Feng; Liu Xiao-Yan; Sun Lei; Luo Hao; Han Ru-Qi

    2007-01-01

    This paper reports that the high-K HfO2 gate dielectrics are fabricated on n-germanium substrates by sputtering Hf on Ge and following by a furnace annealing. The impacts of sputtering ambient, annealing ambient and annealing temperature on the electrical properties of high-K HfO2 gate dielectrics on germanium substrates are investigated.Experimental results indicate that high-K HfO2 gate dielectrics on germanium substrates with good electrical characteristics are obtained, the electrical properties of high-K HfO2 gate dielectrics is strongly correlated with sputtering ambient, annealing ambient and annealing temperature.

  9. Flat-band voltage shift in metal-gate/high-k/Si stacks

    Institute of Scientific and Technical Information of China (English)

    Huang An-Ping; Zheng Xiao-Hu; Xiao Zhi-Song; Yang Zhi-Chao; Wang Mei; Paul K.Chu; Yang Xiao-Dong

    2011-01-01

    In metal-gate/high-k stacks adopted by the 45 nn technology node,the flat-band voltage (Vfb) shift remains one of the most critical challenges,particularly the flat-band voltage roll-off (Vfy roll-off) phenomenon in p-channel metaloxide-semiconductor (pMOS) devices with an ultrathin oxide layer. In this paper,recent progress on the investigation of the Vfb shift and the origin of the Vfb roll-off in the metal-gate/high-k pMOS stacks are reviewed. Methods that can alleviate the Vfb shift phenomenon are summarized and the future research trend is described.

  10. Rendering high charge density of states in ionic liquid-gated MoS 2 transistors

    NARCIS (Netherlands)

    Lee, Y.; Lee, J.; Kim, S.; Park, H.S.

    2014-01-01

    We investigated high charge density of states (DOS) in the bandgap of MoS2 nanosheets with variable temperature measurements on ionic liquid-gated MoS2 transistors. The thermally activated charge transport indicates that the electrical current in the two-dimensional MoS 2 nanosheets under high charg

  11. Field Plate Optimization in Low-Power High-Gain Source-Gated Transistors

    NARCIS (Netherlands)

    Sporea,R.A.; Trainor, M.J.; Young, N.D.; Shannon, J.M.; Silva, S.R.P.

    2012-01-01

    Source-gated transistors (SGTs) have potentially very high output impedance and low saturation voltages, which make them ideal as building blocks for high performance analog circuits fabricated in thin-film technologies. The quality of the saturation is greatly influenced by the design of the field-

  12. A High-Speed Baseline Restorer for Neutron Flux Detection in ITER

    Institute of Scientific and Technical Information of China (English)

    曹宏睿; 李世平; 徐修峰; 袁国梁; 杨青巍; 阴泽杰

    2012-01-01

    A neutron flux monitor .(NFM) is a key diagnostic system in the International Ther- monuclear Experimental Reactor (ITER), and may provide readings of a series of important parameters in fusion reaction processes. As a valuable part of the main electronics system of the NFM, the high-speed baseline restorer we designed is an important signal conversion plug-in which can restore the input signal baseline offset to a zero level, while keeping the output pulse signal waveform from the preamplifier basically unchanged.

  13. Highly efficient hyperentanglement concentration with two steps assisted by quantum swap gates

    Science.gov (United States)

    Ren, Bao-Cang; Long, Gui Lu

    2015-11-01

    We present a two-step hyperentanglement concentration protocol (hyper-ECP) for polarization-spatial hyperentangled Bell states based on the high-capacity character of hyperentanglement resorting to the swap gates, which is used to obtain maximally hyperentangled states from partially hyperentangled pure states in long-distance quantum communication. The swap gate, which is constructed with the giant optical circular birefringence (GOCB) of a diamond nitrogen-vacancy (NV) center embedded in a photonic crystal cavity, can be used to transfer the information in one degree of freedom (DOF) between photon systems. By transferring the useful information between hyperentangled photon pairs, more photon pairs in maximally hyperentangled state can be obtained in our hyper-ECP, and the success probability of the hyper-ECP is greatly improved. Moreover, we show that the high-fidelity quantum gate operations can be achieved by mapping the infidelities to heralded losses even in the weak coupling regime.

  14. High-Performance Wrap-Gated InGaAs Nanowire Field-Effect Transistors with Sputtered Dielectrics

    OpenAIRE

    Li-Fan Shen; SenPo Yip; Zai-xing Yang; Ming Fang; TakFu Hung; Pun, Edwin Y. B.; Ho, Johnny C.

    2015-01-01

    Although wrap-gated nanowire field-effect-transistors (NWFETs) have been explored as an ideal electronic device geometry for low-power and high-frequency applications, further performance enhancement and practical implementation are still suffering from electron scattering on nanowire surface/interface traps between the nanowire channel and gate dielectric as well as the complicated device fabrication scheme. Here, we report the development of high-performance wrap-gated InGaAs NWFETs using c...

  15. Comparison between summing-up algorithms to determine areas of small peaks on high baselines

    Science.gov (United States)

    Shi, Quanlin; Zhang, Jiamei; Chang, Yongfu; Qian, Shaojun

    2005-12-01

    It is found that the minimum detectable activity (MDA) has a same tendency as the relative standard deviation (RSD) and a particular application is characteristic of the ratio of the peak area to the baseline height. Different applications need different algorithms to reduce the RSD of peak areas or the MDA of potential peaks. A model of Gaussian peaks superposed on linear baselines is established to simulate the multichannel spectrum and summing-up algorithms such as total peak area (TPA), and Covell and Sterlinski are compared to find the most appropriate algorithm for different applications. The results show that optimal Covell and Sterlinski algorithms will yield MDA or RSD half lower than TPA when the areas of small peaks on high baselines are to be determined. The conclusion is proved by experiment.

  16. Yttrium scandate thin film as alternative high-permittivity dielectric for germanium gate stack formation

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Cimang, E-mail: cimang@adam.t.u-tokyo.ac.jp; Lee, Choong Hyun; Nishimura, Tomonori; Toriumi, Akira [Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656 (Japan); JST, CREST, 7-3-1 Hongo, Tokyo 113-8656 (Japan)

    2015-08-17

    We investigated yttrium scandate (YScO{sub 3}) as an alternative high-permittivity (k) dielectric thin film for Ge gate stack formation. Significant enhancement of k-value is reported in YScO{sub 3} comparing to both of its binary compounds, Y{sub 2}O{sub 3} and Sc{sub 2}O{sub 3}, without any cost of interface properties. It suggests a feasible approach to a design of promising high-k dielectrics for Ge gate stack, namely, the formation of high-k ternary oxide out of two medium-k binary oxides. Aggressive scaling of equivalent oxide thickness (EOT) with promising interface properties is presented by using YScO{sub 3} as high-k dielectric and yttrium-doped GeO{sub 2} (Y-GeO{sub 2}) as interfacial layer, for a demonstration of high-k gate stack on Ge. In addition, we demonstrate Ge n-MOSFET performance showing the peak electron mobility over 1000 cm{sup 2}/V s in sub-nm EOT region by YScO{sub 3}/Y-GeO{sub 2}/Ge gate stack.

  17. A high-mobility electronic system at an electrolyte-gated oxide surface

    Science.gov (United States)

    Gallagher, Patrick; Lee, Menyoung; Petach, Trevor A.; Stanwyck, Sam W.; Williams, James R.; Watanabe, Kenji; Taniguchi, Takashi; Goldhaber-Gordon, David

    2015-03-01

    Electrolyte gating is a powerful technique for accumulating large carrier densities at a surface. Yet this approach suffers from significant sources of disorder: electrochemical reactions can damage or alter the sample, and the ions of the electrolyte and various dissolved contaminants sit Angstroms from the electron system. Accordingly, electrolyte gating is well suited to studies of superconductivity and other phenomena robust to disorder, but of limited use when reactions or disorder must be avoided. Here we demonstrate that these limitations can be overcome by protecting the sample with a chemically inert, atomically smooth sheet of hexagonal boron nitride. We illustrate our technique with electrolyte-gated strontium titanate, whose mobility when protected with boron nitride improves more than 10-fold while achieving carrier densities nearing 1014 cm-2. Our technique is portable to other materials, and should enable future studies where high carrier density modulation is required but electrochemical reactions and surface disorder must be minimized.

  18. Intermodulation Linearity in High-k/Metal Gate 28 nm RF CMOS Transistors

    Directory of Open Access Journals (Sweden)

    Zhen Li

    2015-09-01

    Full Text Available This paper presents experimental characterization, simulation, and Volterra series based analysis of intermodulation linearity on a high-k/metal gate 28 nm RF CMOS technology. A figure-of-merit is proposed to account for both VGS and VDS nonlinearity, and extracted from frequency dependence of measured IIP3. Implications to biasing current and voltage optimization for linearity are discussed.

  19. Analog and RF Performance Evaluation of Dual Metal Double Gate High-k Stack (DMDG-HKS MOSFETs

    Directory of Open Access Journals (Sweden)

    Santosh K. Gupta

    2013-07-01

    Full Text Available Dual Metal Gate (DMG technology was proposed to reduce the short channel effects (SCE’s of double gate MOSFETs. But, DMG alone is not enough to rectify the problem of gate tunneling current due to thinning of oxide layer with device downscaling. So, the use of high-k dielectric as gate oxide is considered to overcome the gate tunneling effect. But, high gate dielectric thickness leads to higher fringing fields leading to undesirable higher gate capacitance. So, the use of oxide stack i.e. a combination of silicon dioxide and high-k dielectric material is preferred as gate oxide. This paper presents the evaluation of the analog performance of nMOS dual metal double gate with high-k oxide stack (DMDG-HKS MOSFETs, comparing their performance with those exhibited by dual metal double gate (DMDG transistors and single metal double gate (SMDG transistors of identical dimensions. The analog performance has been investigated in subthreshold regime of operation by varying the channel length, gate oxide stack and considering different analog parameters extracted from the 2-D device simulations. It has been observed that the DMDG-HKS devices offer better transconductance gm, early voltage Va, intrinsic gain gm / gd, drain conductance gd, transconductance generation factor gm / Id, transition frequency fT, etc. The variation of these analog parameters has also been investigated by changing the equivalent oxide thickness (EOT and channel length of the DMDG-HKS transistor and has been observed that above parameters tends to improve with channel length and EOT as well.

  20. Silicon electro-optic modulator with high-permittivity gate dielectric layer

    Institute of Scientific and Technical Information of China (English)

    Mengxia Zhu; Zhiping Zhou; Dingshan Gao

    2009-01-01

    A high-permittivity (high-k) material is applied as the gate dielectric layer in a silicon metal-oxidesemiconductor (MOS) capacitor to form a special electro-optic (EO) modulator.Both induced charge density and modulation efficiency in the proposed modulator are improved due to the special structure design and the application of the high-k material.The device has an ultra-compact dimension of 691 μm in length.

  1. Restoring ecological integrity in highly regulated rivers: the role of baseline data and analytical references.

    Science.gov (United States)

    Downs, Peter W; Singer, Maia S; Orr, Bruce K; Diggory, Zooey E; Church, Tamara C; Stella, J C

    2011-10-01

    The goal of restoring ecological integrity in rivers is frequently accompanied by an assumption that a comparative reference reach can be identified to represent minimally impaired conditions. However, in many regulated rivers, no credible historical, morphological or process-based reference reach exists. Resilient restoration designs should instead be framed around naturalization, using multiple analytical references derived from empirically-calibrated field- and model-based techniques to develop an integrated ecological reference condition. This requires baseline data which are rarely collected despite increasing evidence for systematic deficiencies in restoration practice. We illustrate the utility of baseline data collection in restoration planning for the highly fragmented and regulated lower Merced River, California, USA. The restoration design was developed using various baseline data surveys, monitoring, and modeling within an adaptive management framework. Baseline data assisted in transforming conceptual models of ecosystem function into specific restoration challenges, defining analytical references of the expected relationships among ecological parameters required for restoration, and specifying performance criteria for post-project monitoring and evaluation. In this way the study is an example of process-based morphological restoration designed to prompt recovery of ecosystem processes and resilience. For the Merced River, we illustrate that project-specific baseline data collection is a necessary precursor in developing performance-based restoration designs and addressing scale-related uncertainties, such as whether periodic gravel augmentation will sustain bed recovery and whether piecemeal efforts will improve ecological integrity. Given the numerous impediments to full, historical, restoration in many river systems, it seems apparent that projects of naturalization are a critical step in reducing the deleterious impacts of fragmented rivers

  2. Role of Interface Charges on High-k Based Poly-Si and Metal Gate Nano-Scale MOSFETs

    Directory of Open Access Journals (Sweden)

    N. Shashank

    2011-01-01

    Full Text Available The characteristics of typical sub-100 nm high K gate dielectrics MOSFET with different gate materials are simulated by two dimensional device simulators (ATLAS and ATHENA. The impact of interface charges on the characteristics of Poly-Si and TiN metal gate MOSFETs are investigated. The simulation results shows that, at high interface charge densities, the devices with Poly-Si gate degrade much compared to metal gate MOSFET structures. Emphasis is given to study the mobility degradation which stands as a major hurdle with the implementation of high-k dielectrics in nano-scale devices. The advantages of using Watt model over other models for the extraction of channel mobility is also clearly explained. The performance of the high-k MOSFET with metal electrode and poly-silicon electrode is also compared for various interface state charges.

  3. Highly stable organic field-effect transistors with engineered gate dielectrics (Conference Presentation)

    Science.gov (United States)

    Kippelen, Bernard; Wang, Cheng-Yin; Fuentes-Hernandez, Canek; Yun, Minseong; Singh, Ankit K.; Dindar, Amir; Choi, Sangmoo; Graham, Samuel

    2016-11-01

    Organic field-effect transistors (OFETs) have the potential to lead to low-cost flexible displays, wearable electronics, and sensors. While recent efforts have focused greatly on improving the maximum charge mobility that can be achieved in such devices, studies about the stability and reliability of such high performance devices are relatively scarce. In this talk, we will discuss the results of recent studies aimed at improving the stability of OFETs under operation and their shelf lifetime. In particular, we will focus on device architectures where the gate dielectric is engineered to act simultaneously as an environmental barrier layer. In the past, our group had demonstrated solution-processed top-gate OFETs using TIPS-pentacene and PTAA blends as a semiconductor layer with a bilayer gate dielectric layer of CYTOP/Al2O3, where the oxide layer was fabricated by atomic layer deposition, ALD. Such devices displayed high operational stability with little degradation after 20,000 on/off scan cycles or continuous operation (24 h), and high environmental stability when kept in air for more than 2 years, with unchanged carrier mobility. Using this stable device geometry, simple circuits and sensors operating in aqueous conditions were demonstrated. However, the Al2O3 layer was found to degrade due to corrosion under prolonged exposure in aqueous solutions. In this talk, we will report on the use of a nanolaminate (NL) composed of Al2O3 and HfO2 by ALD to replace the Al2O3 single layer in the bilayer gate dielectric use in top-gate OFETs. Such OFETs were found to operate under harsh condition such as immersion in water at 95 °C. This work was funded by the Department of Energy (DOE) through the Bay Area Photovoltaics Consortium (BAPVC) under Award Number DE-EE0004946.

  4. Small High Schools at Work: A Case Study of Six Gates-Funded Schools in New York City. A Report to the Bill & Melinda Gates Foundation

    Science.gov (United States)

    Fancsali, Cheri; Jaffe-Walter, Reva; Mitchell-McKnight, Vernay; Nevarez, Nancy; Orellana, Eliana, Williams Rose, Lea

    2010-01-01

    The Academy for Educational Development (AED) conducted a case study of six public high schools in New York City as part of a multifaceted evaluation of a small schools initiative funded by the Bill & Melinda Gates Foundation. Through surveys, interviews, and focus groups, the authors gathered information and opinions from the schools'…

  5. SOI-Based High-Voltage, High-Temperature Integrated Circuit Gate Driver for SiC-Based Power FETs

    Energy Technology Data Exchange (ETDEWEB)

    Huque, Mohammad A [ORNL; Tolbert, Leon M [ORNL; Blalock, Benjamin [University of Tennessee, Knoxville (UTK); Islam, Syed K [University of Tennessee, Knoxville (UTK)

    2010-01-01

    Silicon carbide (SiC)-based field effect transistors (FETs) are gaining popularity as switching elements in power electronic circuits designed for high-temperature environments like hybrid electric vehicle, aircraft, well logging, geothermal power generation etc. Like any other power switches, SiC-based power devices also need gate driver circuits to interface them with the logic units. The placement of the gate driver circuit next to the power switch is optimal for minimizing system complexity. Successful operation of the gate driver circuit in a harsh environment, especially with minimal or no heat sink and without liquid cooling, can increase the power-to-volume ratio as well as the power-to-weight ratio for power conversion modules such as a DC-DC converter, inverter etc. A silicon-on-insulator (SOI)-based high-voltage, high-temperature integrated circuit (IC) gate driver for SiC power FETs has been designed and fabricated using a commercially available 0.8-m, 2-poly and 3-metal bipolar-complementary metal oxide semiconductor (CMOS)-double diffused metal oxide semiconductor (DMOS) process. The prototype circuit-s maximum gate drive supply can be 40-V with peak 2.3-A sourcing/sinking current driving capability. Owing to the wide driving range, this gate driver IC can be used to drive a wide variety of SiC FET switches (both normally OFF metal oxide semiconductor field effect transistor (MOSFET) and normally ON junction field effect transistor (JFET)). The switching frequency is 20-kHz and the duty cycle can be varied from 0 to 100-. The circuit has been successfully tested with SiC power MOSFETs and JFETs without any heat sink and cooling mechanism. During these tests, SiC switches were kept at room temperature and ambient temperature of the driver circuit was increased to 200-C. The circuit underwent numerous temperature cycles with negligible performance degradation.

  6. High performance high-κ/metal gate complementary metal oxide semiconductor circuit element on flexible silicon

    KAUST Repository

    Sevilla, Galo T.

    2016-02-29

    Thinned silicon based complementary metal oxide semiconductor(CMOS)electronics can be physically flexible. To overcome challenges of limited thinning and damaging of devices originated from back grinding process, we show sequential reactive ion etching of silicon with the assistance from soft polymeric materials to efficiently achieve thinned (40 μm) and flexible (1.5 cm bending radius) silicon based functional CMOSinverters with high-κ/metal gate transistors. Notable advances through this study shows large area of silicon thinning with pre-fabricated high performance elements with ultra-large-scale-integration density (using 90 nm node technology) and then dicing of such large and thinned (seemingly fragile) pieces into smaller pieces using excimer laser. The impact of various mechanical bending and bending cycles show undeterred high performance of flexible siliconCMOSinverters. Future work will include transfer of diced silicon chips to destination site, interconnects, and packaging to obtain fully flexible electronic systems in CMOS compatible way.

  7. A single high dose of escitalopram disrupts sensory gating and habituation, but not sensorimotor gating in healthy volunteers

    DEFF Research Database (Denmark)

    Oranje, Bob; Wienberg, Malene; Glenthøj, Birte Yding

    2011-01-01

    Early mechanisms to limit the input of sensory information to higher brain areas are important for a healthy individual. In previous studies, we found that a low dose of 10mg escitalopram (SSRI) disrupts habituation, without affecting sensory and sensorimotor gating in healthy volunteers. In the ......Early mechanisms to limit the input of sensory information to higher brain areas are important for a healthy individual. In previous studies, we found that a low dose of 10mg escitalopram (SSRI) disrupts habituation, without affecting sensory and sensorimotor gating in healthy volunteers....... In the current study a higher dose of 15mg was used. The hypothesis was that this higher dose of escitalopram would not only disrupt habituation, but also sensory and sensorimotor gating. Twenty healthy male volunteers received either placebo or 15mg escitalopram, after which they were tested in a P50...... suppression, and a habituation and prepulse inhibition (PPI) of the startle reflex paradigm. Escitalopram significantly decreased P50 suppression and habituation, but had no effect on PPI. The results indicate that habituation and sensory gating are disrupted by increased serotonergic activity, while...

  8. End-expiration Respiratory Gating for a High Resolution Stationary Cardiac SPECT system

    Science.gov (United States)

    Chan, Chung; Harris, Mark; Le, Max; Biondi, James; Grobshtein, Yariv; Liu, Yi-Hwa; Sinusas, Albert J.; Liu, Chi

    2014-01-01

    Respiratory and cardiac motions can degrade myocardial perfusion SPECT (MPS) image quality and reduce defect detection and quantitative accuracy. In this study, we developed a dual-respiratory and cardiac gating system for a high resolution fully stationary cardiac SPECT scanner in order to improve the image quality and defect detection. Respiratory motion was monitored using a compressive sensor pillow connected to a dual respiratory-cardiac gating box, which sends cardiac triggers only during end-expiration phases to the single cardiac trigger input on the SPECT scanners. The listmode data were rebinned retrospectively into end-expiration frames for respiratory motion reduction or 8 cardiac gates only during end-expiration phases to compensate for both respiratory and cardiac motions. The proposed method was first validated on a motion phantom in the presence and absence of multiple perfusion defects, and then applied on 11 patient studies with and without perfusion defects. In the normal phantom studies, the end-expiration gated SPECT (EXG-SPECT) reduced respiratory motion blur and increased myocardium to blood pool contrast by 51.2% as compared to the ungated images. The proposed method also yielded an average of 11.2% increase in myocardium to defect contrast as compared to the ungated images in the phantom studies with perfusion defects. In the patient studies, EXG-SPECT significantly improved the myocardium to blood pool contrast (pdefect, EXG-SPECT improved the defect contrast and definition. The dual respiratory-cardiac gating further reduced the blurring effect, increased the myocardium to blood pool contrast significantly by 36% (pdefect characteristics and visualization of fine structures at the expense of increased noise on the patient with defect. The results showed that the proposed methods can effectively reduce motion blur in the images caused by both respiratory and cardiac motions, which may lead to more accurate defect detection and

  9. End-expiration respiratory gating for a high-resolution stationary cardiac SPECT system

    Science.gov (United States)

    Chan, Chung; Harris, Mark; Le, Max; Biondi, James; Grobshtein, Yariv; Liu, Yi-Hwa; Sinusas, Albert J.; Liu, Chi

    2014-10-01

    Respiratory and cardiac motions can degrade myocardial perfusion SPECT (MPS) image quality and reduce defect detection and quantitative accuracy. In this study, we developed a dual respiratory and cardiac gating system for a high-resolution fully stationary cardiac SPECT scanner in order to improve the image quality and defect detection. Respiratory motion was monitored using a compressive sensor pillow connected to a dual respiratory-cardiac gating box, which sends cardiac triggers only during end-expiration phases to the single cardiac trigger input on the SPECT scanners. The listmode data were rebinned retrospectively into end-expiration frames for respiratory motion reduction or eight cardiac gates only during end-expiration phases to compensate for both respiratory and cardiac motions. The proposed method was first validated on a motion phantom in the presence and absence of multiple perfusion defects, and then applied on 11 patient studies with and without perfusion defects. In the normal phantom studies, the end-expiration gated SPECT (EXG-SPECT) reduced respiratory motion blur and increased myocardium to blood pool contrast by 51.2% as compared to the ungated images. The proposed method also yielded an average of 11.2% increase in myocardium to defect contrast as compared to the ungated images in the phantom studies with perfusion defects. In the patient studies, EXG-SPECT significantly improved the myocardium to blood pool contrast (p defect, EXG-SPECT improved the defect contrast and definition. The dual respiratory-cardiac gating further reduced the blurring effect, increased the myocardium to blood pool contrast significantly by 36% (p defect characteristics and visualization of fine structures at the expense of increased noise on the patient with defect. The results showed that the proposed methods can effectively reduce motion blur in the images caused by both respiratory and cardiac motions, which may lead to more accurate defect detection and

  10. Iridium oxides based gate interface of AlGaN/GaN high electron mobility transistors formed by high temperature oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Lalinský, T. [Institute of Electrical Engineering of the Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava (Slovakia); Vallo, M., E-mail: martin.vallo@savba.sk [Institute of Electrical Engineering of the Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava (Slovakia); Vanko, G.; Dobročka, E. [Institute of Electrical Engineering of the Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava (Slovakia); Vincze, A. [International Laser Centre, Ilkovičova 3, 841 04 Bratislava (Slovakia); Osvald, J.; Rýger, I.; Dzuba, J. [Institute of Electrical Engineering of the Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava (Slovakia)

    2013-10-15

    We report on a high temperature forming of iridium oxides (IrO{sub 2}) gates of circular AlGaN/GaN high electron mobility transistors (C-HEMTs) to be predetermined for high temperature applications. IrO{sub 2} gate interfacial layer is formed by high temperature oxidation (T = 500–800 °C, for 1 min) of 15 nm thick Ir gate contact layer. A comprehensive microstructural and electrical characterization of the IrO{sub 2} gates is carried out to explain the improved transport properties and thermal stability of the gate interfaces. It is found that the transformation of Ir gate layer into its crystalline IrO{sub 2} phase at oxidation temperatures of 700 °C and 800 °C provides the high barrier gate interface with prevailing thermionic emission transport mechanism. Accelerated reliability tests are used to confirm C-HEMT thermally stable performance deduced from both the gate interface and 2DEG channel stability. The introduced AlGaN/GaN C-HEMTs with high temperature grown IrO{sub 2} gates seem to be very attractive for both the high temperature operated electronic and sensor devices.

  11. Improvement of high-fold gamma-ray data processing: the spherical gate method

    CERN Document Server

    Theisen, C; Stezowski, O; Vivien, J P

    1999-01-01

    A new method for optimizing the processing of events from a highly efficient large array gamma-ray detector is described in this article. The spherical gates technique, developed to project high-fold events, consists of optimizing n-dimensional gate shape as a function of peak width and shape of each detector. Formulas in closed form are proposed for determining the projected statistics from coincidence fold and peak shape and for estimating the increased quality of projected spectra. This procedure has been tested on high-fold, high statistics data sets including superdeformed cascades. Compared to the classical 'square-gate' technique, better peak-to-background ratios as well as a reduction in fluctuations are observed. A quality parameter is defined to characterize the optimal parameter set. This method leads roughly to a gain in spectral quality equivalent of one fold. It is also shown that the efficiency of the method increases with coincidence fold. This should be particularly suited for future higher-f...

  12. High performance In2O3 nanowire transistors using organic gate nanodielectrics

    Science.gov (United States)

    Ju, Sanghyun; Ishikawa, Fumiaki; Chen, Pochiang; Chang, Hsiao-Kang; Zhou, Chongwu; Ha, Young-geun; Liu, Jun; Facchetti, Antonio; Marks, Tobin J.; Janes, David B.

    2008-06-01

    We report the fabrication of high performance nanowire transistors (NWTs) using In2O3 nanowires as the active channel and a self-assembled nanodielectric (SAND) as the gate insulator. The SAND-based single In2O3 NWTs are controlled by individually addressed gate electrodes. These devices exhibit n-type transistor characteristics with an on-current of ˜25μA for a single In2O3 nanowire at 2.0Vds, 2.1Vgs, a subthreshold slope of 0.2V/decade, an on-off current ratio of 106, and a field-effect mobility of ˜1450cm2/Vs. These results demonstrate that SAND-based In2O3 NWTs are promising candidates for high performance nanoscale logic technologies.

  13. Gate-tunable electron interaction in high-κ dielectric films

    Science.gov (United States)

    Kondovych, Svitlana; Luk’Yanchuk, Igor; Baturina, Tatyana I.; Vinokur, Valerii M.

    2017-02-01

    The two-dimensional (2D) logarithmic character of Coulomb interaction between charges and the resulting logarithmic confinement is a remarkable inherent property of high dielectric constant (high-κ) thin films with far reaching implications. Most and foremost, this is the charge Berezinskii-Kosterlitz-Thouless transition with the notable manifestation, low-temperature superinsulating topological phase. Here we show that the range of the confinement can be tuned by the external gate electrode and unravel a variety of electrostatic interactions in high-k films. We find that by reducing the distance from the gate to the film, we decrease the spatial range of the 2D long-range logarithmic interaction, changing it to predominantly dipolar or even to exponential one at lateral distances exceeding the dimension of the film-gate separation. Our findings offer a unique laboratory for the in-depth study of topological phase transitions and related phenomena that range from criticality of quantum metal- and superconductor-insulator transitions to the effects of charge-trapping and Coulomb scalability in memory nanodevices.

  14. Comprehensive Study of Lanthanum Aluminate High-Dielectric-Constant Gate Oxides for Advanced CMOS Devices

    Directory of Open Access Journals (Sweden)

    Masamichi Suzuki

    2012-03-01

    Full Text Available A comprehensive study of the electrical and physical characteristics of Lanthanum Aluminate (LaAlO3 high-dielectric-constant gate oxides for advanced CMOS devices was performed. The most distinctive feature of LaAlO3 as compared with Hf-based high-k materials is the thermal stability at the interface with Si, which suppresses the formation of a low-permittivity Si oxide interfacial layer. Careful selection of the film deposition conditions has enabled successful deposition of an LaAlO3 gate dielectric film with an equivalent oxide thickness (EOT of 0.31 nm. Direct contact with Si has been revealed to cause significant tensile strain to the Si in the interface region. The high stability of the effective work function with respect to the annealing conditions has been demonstrated through comparison with Hf-based dielectrics. It has also been shown that the effective work function can be tuned over a wide range by controlling the La/(La + Al atomic ratio. In addition, gate-first n-MOSFETs with ultrathin EOT that use sulfur-implanted Schottky source/drain technology have been fabricated using a low-temperature process.

  15. Top-gate zinc tin oxide thin-film transistors with high bias and environmental stress stability

    Science.gov (United States)

    Fakhri, M.; Theisen, M.; Behrendt, A.; Görrn, P.; Riedl, T.

    2014-06-01

    Top gated metal-oxide thin-film transistors (TFTs) provide two benefits compared to their conventional bottom-gate counterparts: (i) The gate dielectric may concomitantly serve as encapsulation layer for the TFT channel. (ii) Damage of the dielectric due to high-energetic particles during channel deposition can be avoided. In our work, the top-gate dielectric is prepared by ozone based atomic layer deposition at low temperatures. For ultra-low gas permeation rates, we introduce nano-laminates of Al2O3/ZrO2 as dielectrics. The resulting TFTs show a superior environmental stability even at elevated temperatures. Their outstanding stability vs. bias stress is benchmarked against bottom-gate devices with encapsulation.

  16. Polymer thin-film transistor based on a high dielectric constant gate insulator

    Institute of Scientific and Technical Information of China (English)

    Lü Wen; Peng Jun-Biao; Yang Kai-Xia; Lan Lin-Feng; Niu Qiao-Li; Cao Yong

    2007-01-01

    In this paper full polymer thin-film transistors (PTFTs) based on Poly (acrylonitrile) (PAN) as the gate dielectric and poly (2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene-vinylene) (MEH-PPV) as the semiconductor layer were investigated by using different channel width/length ratios. Relatively high dielectric constant of the polymer dielectric layer (6.27) can remarkably reduce the threshold voltage of the transistors to below-3 V. Hole field-effect mobility of MEH-PPV of the PTFTs was about 4.8 × 10-4 cm2/Vs, and on/off current ratio was larger than 102, which was comparable with that of transistors with widely used Poly (4-vinyl phenol) (PVP) or SiO2 as gate dielectrics.

  17. A high performance InAlN/GaN HEMT with low Ron and gate leakage

    Science.gov (United States)

    Chunlei, Ma; Guodong, Gu; Yuanjie, Lü

    2016-02-01

    InAlN/GaN high-electron mobility transistors (HEMTs) with a gate length of 100 nm and oxygen plasma treatment were fabricated. A Si/Ti/Al/Ni/Au ohmic contact was also used to reduce the contact resistance. DC and RF characteristics of the devices were measured. The fabricated devices show a maximum drain current density of 2.18 A/mm at VGS = 2 V, a low on-resistance (Ron) of 1.49 ω·mm and low gate leakage current. An excellent frequency response was also obtained. The current cut-off frequency (fT) is 81 GHz and the maximum oscillation frequency is 138 GHz, respectively. Project supported by the National Natural Science Foundation of China (No. 61306113).

  18. Electrical characteristics of polycrystalline Si layers embedded into high- k Al 2O 3 gate layers

    Science.gov (United States)

    Park, Byoungjun; Cho, Kyoungah; Kim, Sangsig

    2008-09-01

    The electrical characteristics of polycrystalline Si (poly Si) layers embedded into high- k Al 2O 3 (alumina) gate layers are investigated in this work. The capacitance versus voltage ( C- V) curves obtained from the metal-alumina-polysilicon-alumina-silicon (MASAS) capacitors exhibit significant threshold voltage shifts, and the width of their hysteresis window is dependent on the range of the voltage sweep. The counterclockwise hysteresis observed in the C- V curves indicates that electrons originating from the p-type Si substrate in the inversion condition are trapped in the floating gate layer consisting of the poly Si layer present between the top and bottom Al 2O 3 layers in the MASAS capacitor. Also, current versus voltage ( I- V) measurements are performed to examine the electrical characteristics of the fabricated capacitors. The I- V measurements reveal that our MASAS capacitors show a very low leakage current density, compared to the previously reported results.

  19. Highly flexible SRAM cells based on novel tri-independent-gate FinFET

    Science.gov (United States)

    Liu, Chengsheng; Zheng, Fanglin; Sun, Yabin; Li, Xiaojin; Shi, Yanling

    2017-10-01

    In this paper, a novel tri-independent-gate (TIG) FinFET is proposed for highly flexible SRAM cells design. To mitigate the read-write conflict, two kinds of SRAM cells based on TIG FinFETs are designed, and high tradeoff are obtained between read stability and speed. Both cells can offer multi read operations for frequency requirement with single voltage supply. In the first TIG FinFET SRAM cell, the strength of single-fin access transistor (TIG FinFET) can be flexibly adjusted by selecting five different modes to meet the needs of dynamic frequency design. Compared to the previous double-independent-gate (DIG) FinFET SRAM cell, 12.16% shorter read delay can be achieved with only 1.62% read stability decrement. As for the second TIG FinFET SRAM cell, pass-gate feedback technology is applied and double-fin TIG FinFETs are used as access transistors to solve the severe write-ability degradation. Three modes exist to flexibly adjust read speed and stability, and 68.2% larger write margin and 51.7% shorter write delay are achieved at only the expense of 26.2% increase in leakage power, with the same layout area as conventional FinFET SRAM cell.

  20. High-speed radiometric imaging with a gated, intensified, digitally controlled camera

    Science.gov (United States)

    Ross, Charles C.; Sturz, Richard A.

    1997-05-01

    The development of an advanced instrument for real-time radiometric imaging of high-speed events is described. The Intensified Digitally-Controlled Gated (IDG) camera is a microprocessor-controlled instrument based on an intensified CCD that is specifically designed to provide radiometric optical data. The IDG supports a variety of camera- synchronous and camera-asynchronous imaging tasks in both passive imaging and active laser range-gated applications. It features both automatic and manual modes of operation, digital precision and repeatability, and ease of use. The IDG produces radiometric imagery by digitally controlling the instrument's optical gain and exposure duration, and by encoding and annotating the parameters necessary for radiometric analysis onto the resultant video signal. Additional inputs, such as date, time, GPS, IRIG-B timing, and other data can also be encoded and annotated. The IDG optical sensitivity can be readily calibrated, with calibration data tables stored in the camera's nonvolatile flash memory. The microprocessor then uses this data to provide a linear, calibrated output. The IDG possesses both synchronous and asynchronous imaging modes in order to allow internal or external control of exposure, timing, and direct interface to external equipment such as event triggers and frame grabbers. Support for laser range-gating is implemented by providing precise asynchronous CCD operation and nanosecond resolution of the intensifier photocathode gate duration and timing. Innovative methods used to control the CCD for asynchronous image capture, as well as other sensor and system considerations relevant to high-speed imaging are discussed in this paper.

  1. The High Energy Neutrino Nuisance at a Medium Baseline Reactor Experiment

    CERN Document Server

    Ciuffoli, Emilio; Zhang, Xinmin

    2012-01-01

    10 years from now medium baseline reactor experiments will attempt to determine the neutrino mass hierarchy from the differences (RL+PV) between the extrema of the Fourier transformed neutrino spectra. Recently Qian et al. have claimed that this goal may be impeded by the strong dependence of the difference parameter RL+PV on the reactor neutrino flux and on slight variations of Delta M^2_32. We demonstrate that this effect results from a spurious dependence of the difference parameter on the very high energy (8+ MeV) tail of the reactor neutrino spectrum. This dependence is spurious because the high energy tail depends upon decays of exotic isotopes and is insensitive to the mass hierarchy. An energy-dependent weight in the Fourier transform not only eliminates this spurious dependence but in fact increases the chance of correctly determining the hierarchy.

  2. A quantum dot asymmetric self-gated nanowire FET for high sensitive detection

    Directory of Open Access Journals (Sweden)

    Zhangchun Shi

    2015-01-01

    Full Text Available We present a novel device for weak light detection based on self-gated nanowire field effect structure with embedded quantum dots beside the nanowire current channel. The quantum dot with high localization energy will make the device work at high detecting temperature and the nano-channel structure will provide high photocurrent gain. Simulation has been done to optimize the structure, explain the working principle and electrical properties of the devices. The nonlinear current-voltage characteristics have been demonstrated at different temperatures. The responsivity of the device is proven to be more than 4.8 × 106A/W at 50 K.

  3. Backside versus frontside advanced chemical analysis of high-k/metal gate stacks

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, E., E-mail: eugenie.martinez@cea.fr [Univ Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Saidi, B. [STMicroelectronics, 850 rue Jean Monnet, 38926 Rousset Cedex, Crolles (France); Veillerot, M. [Univ Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Caubet, P. [STMicroelectronics, 850 rue Jean Monnet, 38926 Rousset Cedex, Crolles (France); Fabbri, J-M. [Univ Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Piallat, F. [STMicroelectronics, 850 rue Jean Monnet, 38926 Rousset Cedex, Crolles (France); Gassilloud, R. [Univ Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Schamm-Chardon, S. [CEMES-CNRS et Université de Toulouse, 29 rue Jeanne Marvig, 31055 Toulouse (France)

    2015-08-15

    Highlights: • The backside approach is a promising solution for advanced chemical characterization of future MOSFETs. • Frontside ToF-SIMS and Auger depth profiles are affected by cumulative mixing effects and thus not relevant for analyzing ultra-thin layers. • Higher in-depth resolution is possible in the backside approach for Auger and ToF-SIMS depth profiling. • Backside depth profiling allows revealing ultra-thin layers and elemental in-depth redistribution inside high-k/metal gate stacks. • Backside XPS allows preserving the full metal gate, thus enabling the analysis of real technological samples. - Abstract: Downscaling of transistors beyond the 14 nm technological node requires the implementation of new architectures and materials. Advanced characterization methods are needed to gain information about the chemical composition of buried layers and interfaces. An effective approach based on backside analysis is presented here. X-ray photoelectron spectroscopy, Auger depth profiling and time-of-flight secondary ions mass spectrometry are combined to investigate inter-diffusion phenomena. To highlight improvements related to the backside method, backside and frontside analyses are compared. Critical information regarding nitrogen, oxygen and aluminium redistribution inside the gate stacks is obtained only in the backside configuration.

  4. High-k perovskite gate oxide BaHfO3

    Directory of Open Access Journals (Sweden)

    Young Mo Kim

    2017-01-01

    Full Text Available We have investigated epitaxial BaHfO3 as a high-k perovskite dielectric. From x-ray diffraction measurement, we confirmed the epitaxial growth of BaHfO3 on BaSnO3 and MgO. We measured optical and dielectric properties of the BaHfO3 gate insulator; the optical bandgap, the dielectric constant, and the breakdown field. Furthermore, we fabricated a perovskite heterostructure field effect transistor using epitaxial BaHfO3 as a gate insulator and La-doped BaSnO3 as a channel layer on SrTiO3 substrate. To reduce the threading dislocations and enhance the electrical properties of the channel, an undoped BaSnO3 buffer layer was grown on SrTiO3 substrates before the channel layer deposition. The device exhibited a field effect mobility value of 52.7 cm2 V−1 s−1, a Ion/Ioff ratio higher than 107, and a subthreshold swing value of 0.80 V dec−1. We compare the device performances with those of other field effect transistors based on BaSnO3 channels and different gate oxides.

  5. High capacitance organic field-effect transistors with modified gate insulator surface

    Science.gov (United States)

    Majewski, L. A.; Schroeder, R.; Grell, M.; Glarvey, P. A.; Turner, M. L.

    2004-11-01

    In this paper, we report on flexible, high capacitance, pentacene, and regioregular poly(3-hexylthiophene) (rr-P3HT) organic field-effect transistors fabricated on metallized Mylar films. The gate insulator, Al2O3, was prepared by means of anodization. We show that covering the anodized gate insulator with an octadecyltrichlorosilane self-assembled monolayer or apoly(α-methylstyrene) capping layer has the same effect on carrier mobility as for thermally grown silicon oxide. In addition, temperature-dependent measurements of mobility were performed on transistors fabricated with and without modification of the gate dielectric. In the case of both the pentacene and the rr-P3HT transistors, the μ(T ) behavior shows that the cause of the mobility enhancement through surface modification is not a reduction in the level of energetic disorder (σ in Bässler's model), as in the case of the fully amorphous organic semiconductor poly(triarylamine) [Veres et al., Adv. Funct. Mater. 13, 199 (2003)]. It appears that the surface modification improves mobility by changing the morphology of the semiconducting films.

  6. Highly efficient gate-tunable photocurrent generation in vertical heterostructures of layered materials

    Science.gov (United States)

    Yu, Woo Jong; Liu, Yuan; Zhou, Hailong; Yin, Anxiang; Li, Zheng; Huang, Yu; Duan, Xiangfeng

    2013-12-01

    Layered materials of graphene and MoS2, for example, have recently emerged as an exciting material system for future electronics and optoelectronics. Vertical integration of layered materials can enable the design of novel electronic and photonic devices. Here, we report highly efficient photocurrent generation from vertical heterostructures of layered materials. We show that vertically stacked graphene-MoS2-graphene and graphene-MoS2-metal junctions can be created with a broad junction area for efficient photon harvesting. The weak electrostatic screening effect of graphene allows the integration of single or dual gates under and/or above the vertical heterostructure to tune the band slope and photocurrent generation. We demonstrate that the amplitude and polarity of the photocurrent in the gated vertical heterostructures can be readily modulated by the electric field of an external gate to achieve a maximum external quantum efficiency of 55% and internal quantum efficiency up to 85%. Our study establishes a method to control photocarrier generation, separation and transport processes using an external electric field.

  7. A PNPN tunnel field-effect transistor with high-k gate and low-k fringe dielectrics

    Institute of Scientific and Technical Information of China (English)

    Cui Ning; Liang Renrong; Wang Jing; Zhou Wei; Xu Jun

    2012-01-01

    A PNPN tunnel field effect transistor (TFET) with a high-k gate dielectric and a low-k fringe dielectric is introduced.The effects of the gate and fringe electric fields on the TFET's performance were investigated through two-dimensional simulations.The results showed that a high gate dielectric constant is preferable for enhancing the gate control over the channel,while a low fringe dielectric constant is useful to increase the band-to-band tunneling probability.The TFET device with the proposed structure has good switching characteristics,enhanced on-state current,and high process tolerance.It is suitable for low-power applications and could become a potential substitute in next-generation complementary metal-oxide-semiconductor technology.

  8. A Very Robust AlGaN/GaN HEMT Technology to High Forward Gate Bias and Current

    Directory of Open Access Journals (Sweden)

    Bradley D. Christiansen

    2012-01-01

    Full Text Available Reports to date of GaN HEMTs subjected to forward gate bias stress include varied extents of degradation. We report an extremely robust GaN HEMT technology that survived—contrary to conventional wisdom—high forward gate bias (+6 V and current (>1.8 A/mm for >17.5 hours exhibiting only a slight change in gate diode characteristic, little decrease in maximum drain current, with only a 0.1 V positive threshold voltage shift, and, remarkably, a persisting breakdown voltage exceeding 200 V.

  9. Flexible semi-transparent silicon (100) fabric with high-k/metal gate devices

    KAUST Repository

    Rojas, Jhonathan Prieto

    2013-01-07

    Can we build a flexible and transparent truly high performance computer? High-k/metal gate stack based metal-oxide-semiconductor capacitor devices are monolithically fabricated on industry\\'s most widely used low-cost bulk single-crystalline silicon (100) wafers and then released as continuous, mechanically flexible, optically semi-transparent and high thermal budget compatible silicon fabric with devices. This is the first ever demonstration with this set of materials which allows full degree of freedom to fabricate nanoelectronics devices using state-of-the-art CMOS compatible processes and then to utilize them in an unprecedented way for wide deployment over nearly any kind of shape and architecture surfaces. Electrical characterization shows uncompromising performance of post release devices. Mechanical characterization shows extra-ordinary flexibility (minimum bending radius of 1 cm) making this generic process attractive to extend the horizon of flexible electronics for truly high performance computers. Schematic and photograph of flexible high-k/metal gate MOSCAPs showing high flexibility and C-V plot showing uncompromised performance. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Influence of Respiratory Gating, Image Filtering, and Animal Positioning on High-Resolution Electrocardiography-Gated Murine Cardiac Single-Photon Emission Computed Tomography

    Directory of Open Access Journals (Sweden)

    Chao Wu

    2015-01-01

    Full Text Available Cardiac parameters obtained from single-photon emission computed tomographic (SPECT images can be affected by respiratory motion, image filtering, and animal positioning. We investigated the influence of these factors on ultra-high-resolution murine myocardial perfusion SPECT. Five mice were injected with 99m technetium (99mTc-tetrofosmin, and each was scanned in supine and prone positions in a U-SPECT-II scanner with respiratory and electrocardiographic (ECG gating. ECG-gated SPECT images were created without applying respiratory motion correction or with two different respiratory motion correction strategies. The images were filtered with a range of three-dimensional gaussian kernels, after which end-diastolic volumes (EDVs, end-systolic volumes (ESVs, and left ventricular ejection fractions were calculated. No significant differences in the measured cardiac parameters were detected when any strategy to reduce or correct for respiratory motion was applied, whereas big differences (> 5% in EDV and ESV were found with regard to different positioning of animals. A linear relationship (p < .001 was found between the EDV or ESV and the kernel size of the gaussian filter. In short, respiratory gating did not significantly affect the cardiac parameters of mice obtained with ultra-high-resolution SPECT, whereas the position of the animals and the image filters should be the same in a comparative study with multiple scans to avoid systematic differences in measured cardiac parameters.

  11. Method for reworkable packaging of high speed, low electrical parasitic power electronics modules through gate drive integration

    Science.gov (United States)

    Passmore, Brandon; Cole, Zach; Whitaker, Bret; Barkley, Adam; McNutt, Ty; Lostetter, Alexander

    2016-08-02

    A multichip power module directly connecting the busboard to a printed-circuit board that is attached to the power substrate enabling extremely low loop inductance for extreme environments such as high temperature operation. Wire bond interconnections are taught from the power die directly to the busboard further enabling enable low parasitic interconnections. Integration of on-board high frequency bus capacitors provide extremely low loop inductance. An extreme environment gate driver board allows close physical proximity of gate driver and power stage to reduce overall volume and reduce impedance in the control circuit. Parallel spring-loaded pin gate driver PCB connections allows a reliable and reworkable power module to gate driver interconnections.

  12. Gate-tunable high mobility remote-doped InSb/In1−xAlxSb quantum well

    NARCIS (Netherlands)

    Yi, W.; Kiselev, A.A.; Thorp, J.; Noah, R.; Nguyen, B.M.; Bui, S.; Rajavel, R.D.; Hussain, T.; Gyure, M.F.; Kratz, P.; Qian, Q.; Manfra, M.J.; Pribiag, V.S.; Kouwenhoven, L.P.; Marcus, C.M.; Sokolich, M.

    2015-01-01

    Gate-tunable high-mobility InSb/In1−xAlxSb quantum wells (QWs) grown on GaAs substrates are reported. The QW two-dimensional electron gas (2DEG) channel mobility in excess of 200 000 cm2/V s is measured at T = 1.8 K. In asymmetrically remote-doped samples with an HfO2 gate dielectric formed by atomi

  13. AlGaN/GaN high-electron-mobility transistors with transparent gates by Al-doped ZnO

    Institute of Scientific and Technical Information of China (English)

    Wang Chong; He Yun-Long; Zheng Xue-Feng; Ma Xiao-Hua; Zhang Jin-Cheng; Hao Yue

    2013-01-01

    AlGaN/GaN high-electron-mobility transistors (HEMTs) with Al-doped ZnO (AZO) transparent gate electrodes are fabricated,and Ni/Au/Ni-gated HEMTs are produced in comparison.The AZO-gated HEMTs show good DC characteristics and Schottky rectifying characteristics,and the gate electrodes achieve excellent transparencies.Compared with Ni/Au/Ni-gated HEMTs,AZO-gated HEMTs show a low saturation current,high threshold voltage,high Schottky barrier height,and low gate reverse leakage current.Due to the higher gate resistivity,AZO-gated HEMTs exhibit a current-gain cutoff frequency (fT) of 10 GHz and a power gain cutoff frequency (fmax) of 5 GHz,and lower maximum oscillation frequency than Ni/Au/Ni-gated HEMTs.Moreover,the C-V characteristics are measured and the gate interface characteristics of the AZO-gated devices are investigated by a C-V dual sweep.

  14. High-fidelity single-shot Toffoli gate via quantum control

    Science.gov (United States)

    Sanders, Barry; Zahedinejad, Ehsan; Ghosh, Joydip

    2015-05-01

    A single-shot Toffoli, or controlled-controlled-NOT, gate is desirable for classical and for quantum information processing. The Toffoli gate alone is universal for reversible computing and, accompanied by the Hadamard gate, are universal for quantum computing. The Toffoli gate is a key ingredient for (non-topological) quantum error correction. Currently Toffoli gates are achieved by decomposing into sequentially implemented single- and two-qubit gates, which requires much longer times and yields lower overall fidelities compared to a single-shot implementation. We develop a quantum-control procedure to directly construct single-shot Toffoli gates and devise a scheme for three nearest-neighbor-coupled superconducting transmon systems that should operate with 99.9% fidelity under realistic conditions. The gate is achieved by a non-greedy quantum control procedure using our enhanced version of the Differential Evolution algorithm. arXiv:1501.04676 Acknowledges support from AITF, NSERC, USARO and 1000 Talent Plan.

  15. MBE and ALD grown High k Dielectrics Gate Stacks on GaN

    Science.gov (United States)

    Chang, Y. C.; Lee, K. Y.; Lee, W. C.; Lin, T. D.; Lee, Y. J.; Huang, M. L.; Hong, M.; Kwo, J.; Wang, Y. H.

    2007-03-01

    III-nitride compound semiconductors are attractive for high-temperature and high-power MOSFET applications due to their intrinsic properties of wide band gap, high breakdown field, and high saturation velocity under high fields. In this work GaN-based high k MOS diodes were fabricated using MBE-grown Ga2O3(Gd2O3), MBE-grown HfO2 and ALD-grown HfO2 as the gate dielectrics with dielectric constants of 14.7, 17.4 and 16.5, respectively. All MOS diodes exhibited low leakage (XPS and with the bandgaps of the oxides. For example, the ALD-grown HfO2-GaN at the interfaces gave approximately δEC and δEV of 1.2 eV and 1.1 eV, respectively.

  16. High-throughput gated photon counter with two detection windows programmable down to 70 ps width

    Energy Technology Data Exchange (ETDEWEB)

    Boso, Gianluca; Tosi, Alberto, E-mail: alberto.tosi@polimi.it; Zappa, Franco [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Piazza Leonardo Da Vinci 32, 20133 Milano (Italy); Mora, Alberto Dalla [Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo Da Vinci 32, 20133 Milano (Italy)

    2014-01-15

    We present the design and characterization of a high-throughput gated photon counter able to count electrical pulses occurring within two well-defined and programmable detection windows. We extensively characterized and validated this instrument up to 100 Mcounts/s and with detection window width down to 70 ps. This instrument is suitable for many applications and proves to be a cost-effective and compact alternative to time-correlated single-photon counting equipment, thanks to its easy configurability, user-friendly interface, and fully adjustable settings via a Universal Serial Bus (USB) link to a remote computer.

  17. High-throughput gated photon counter with two detection windows programmable down to 70 ps width.

    Science.gov (United States)

    Boso, Gianluca; Tosi, Alberto; Dalla Mora, Alberto; Zappa, Franco

    2014-01-01

    We present the design and characterization of a high-throughput gated photon counter able to count electrical pulses occurring within two well-defined and programmable detection windows. We extensively characterized and validated this instrument up to 100 Mcounts/s and with detection window width down to 70 ps. This instrument is suitable for many applications and proves to be a cost-effective and compact alternative to time-correlated single-photon counting equipment, thanks to its easy configurability, user-friendly interface, and fully adjustable settings via a Universal Serial Bus (USB) link to a remote computer.

  18. Comprehensive behavioral model of dual-gate high voltage JFET and pinch resistor

    Science.gov (United States)

    Banáš, Stanislav; Paňko, Václav; Dobeš, Josef; Hanyš, Petr; Divín, Jan

    2016-09-01

    Many analog technologies operate in large voltage range and therefore include at least one or more high voltage devices built from low doped layers. Such devices exhibit effects not covered by standard compact models, namely pinching (depletion) effects, in high voltage FETs often called quasisaturation. For example, the conventional compact JFET model is insufficient and oversimplified. Its scalability is controlled by the area factor, which only multiplies currents and capacitances but does not take into account existing 3-D effects. Also the optional second independent gate is missing. Therefore, the customized four terminal (4T) model written in Verilog-A (FitzPatrick and Miller, 2007; Sagdeo, 2007) was developed. It converges very well, its simulation speed is comparable with conventional compact models, and contains all required phenomena, including parasitic effects as, for example, impact ionization. This model has universal usage for many types of devices in various high voltage technologies such as stand-alone voltage dependent resistor, pinch resistor, drift area of power FET, part of special high side or start-up devices, and dual-gate JFET.

  19. High-fidelity two-qubit gates via dynamical decoupling of local 1 /f noise at the optimal point

    Science.gov (United States)

    D'Arrigo, A.; Falci, G.; Paladino, E.

    2016-08-01

    We investigate the possibility of achieving high-fidelity universal two-qubit gates by supplementing optimal tuning of individual qubits with dynamical decoupling (DD) of local 1 /f noise. We consider simultaneous local pulse sequences applied during the gate operation and compare the efficiencies of periodic, Carr-Purcell, and Uhrig DD with hard π pulses along two directions (πz /y pulses). We present analytical perturbative results (Magnus expansion) in the quasistatic noise approximation combined with numerical simulations for realistic 1 /f noise spectra. The gate efficiency is studied as a function of the gate duration, of the number n of pulses, and of the high-frequency roll-off. We find that the gate error is nonmonotonic in n , decreasing as n-α in the asymptotic limit, α ≥2 , depending on the DD sequence. In this limit πz-Urhig is the most efficient scheme for quasistatic 1 /f noise, but it is highly sensitive to the soft UV cutoff. For small number of pulses, πz control yields anti-Zeno behavior, whereas πy pulses minimize the error for a finite n . For the current noise figures in superconducting qubits, two-qubit gate errors ˜10-6 , meeting the requirements for fault-tolerant quantum computation, can be achieved. The Carr-Purcell-Meiboom-Gill sequence is the most efficient procedure, stable for 1 /f noise with UV cutoff up to gigahertz.

  20. Influence of aripiprazole, risperidone, and amisulpride on sensory and sensorimotor gating in healthy 'low and high gating' humans and relation to psychometry.

    Science.gov (United States)

    Csomor, Philipp A; Preller, Katrin H; Geyer, Mark A; Studerus, Erich; Huber, Theodor; Vollenweider, Franz X

    2014-09-01

    Despite advances in the treatment of schizophrenia spectrum disorders with atypical antipsychotics (AAPs), there is still need for compounds with improved efficacy/side-effect ratios. Evidence from challenge studies suggests that the assessment of gating functions in humans and rodents with naturally low-gating levels might be a useful model to screen for novel compounds with antipsychotic properties. To further evaluate and extend this translational approach, three AAPs were examined. Compounds without antipsychotic properties served as negative control treatments. In a placebo-controlled, within-subject design, healthy males received either single doses of aripiprazole and risperidone (n=28), amisulpride and lorazepam (n=30), or modafinil and valproate (n=30), and placebo. Prepulse inhibiton (PPI) and P50 suppression were assessed. Clinically associated symptoms were evaluated using the SCL-90-R. Aripiprazole, risperidone, and amisulpride increased P50 suppression in low P50 gaters. Lorazepam, modafinil, and valproate did not influence P50 suppression in low gaters. Furthermore, low P50 gaters scored significantly higher on the SCL-90-R than high P50 gaters. Aripiprazole increased PPI in low PPI gaters, whereas modafinil and lorazepam attenuated PPI in both groups. Risperidone, amisulpride, and valproate did not influence PPI. P50 suppression in low gaters appears to be an antipsychotic-sensitive neurophysiologic marker. This conclusion is supported by the association of low P50 suppression and higher clinically associated scores. Furthermore, PPI might be sensitive for atypical mechanisms of antipsychotic medication. The translational model investigating differential effects of AAPs on gating in healthy subjects with naturally low gating can be beneficial for phase II/III development plans by providing additional information for critical decision making.

  1. High baseline activity in inferior temporal cortex improves neural and behavioral discriminability during visual categorization

    Directory of Open Access Journals (Sweden)

    Nazli eEmadi

    2014-11-01

    Full Text Available Spontaneous firing is a ubiquitous property of neural activity in the brain. Recent literature suggests that this baseline activity plays a key role in perception. However, it is not known how the baseline activity contributes to neural coding and behavior. Here, by recording from the single neurons in the inferior temporal cortex of monkeys performing a visual categorization task, we thoroughly explored the relationship between baseline activity, the evoked response, and behavior. Specifically we found that a low-frequency (< 8 Hz oscillation in the spike train, prior and phase-locked to the stimulus onset, was correlated with increased gamma power and neuronal baseline activity. This enhancement of the baseline activity was then followed by an increase in the neural selectivity and the response reliability and eventually a higher behavioral performance.

  2. An Area Efficient and High Speed Reversible Multiplier Using NS Gate

    Directory of Open Access Journals (Sweden)

    Venkateswarlu

    2017-01-01

    Full Text Available In digital computer system a major problem has been found that the Power dissipation which leads to bring some research on the methods to decrease this Area efficient, high speed. This is the main cause to give birth to reversible computing systems for digital computers and designs. Reversible computing is the path to future computing technologies, which all happen to use reversible logic. In addition, reversible computing will become mandatory because of the necessity to decrease power consumption. Reversible logic circuits have the same number of inputs and outputs, and have one-to-one mapping between vectors of inputs and outputs; thus the vector of input states can be always reconstructed from the vector of output states. Consequently, a computation is reversible, if it is always possible to uniquely recover the input, given the output. Each gate can be made reversible by adding some additional input and output wires if necessary. The main aim of this reversible computing is to lower the power dissipation, area efficient and high speed and some other advantages like security of data and prevention of errors etc... Reversible logic has so many applications low power CMOS, nanotechnology, DNA computing and quantum computing. There are two primary design implementations in this study which are the major spotlights. The first one is reversible design gate and the second one is multiplier design using reversible gates. In this manuscript we have implemented a 8 * 8 reversible design called “NSG(Non linear Sign Flip”. The total project is implemented in Xilinx 14.7 ISE with Spartan 3E family

  3. A wide bandgap silicon carbide (SiC) gate driver for high-temperature and high-voltage applications

    Energy Technology Data Exchange (ETDEWEB)

    Lamichhane, Ranjan [University of Arkansas; Ericson, Milton Nance [ORNL; Frank, Steven Shane [ORNL; BRITTONJr., CHARLES L. [Oak Ridge National Laboratory (ORNL); Marlino, Laura D [ORNL; Mantooth, Alan [University of Arkansas; Francis, Matt [APEI, Inc.; Shepherd, Dr. Paul [University of Arkansas; Glover, Dr. Michael [University of Arkansas; Podar, Mircea [ORNL; Perez, M [University of Arkansas; Mcnutt, Tyler [APEI, Inc.; Whitaker, Mr. Bret [APEI, Inc.; Cole, Mr. Zach [APEI, Inc.

    2014-01-01

    Limitations of silicon (Si) based power electronic devices can be overcome with Silicon Carbide (SiC) because of its remarkable material properties. SiC is a wide bandgap semiconductor material with larger bandgap, lower leakage currents, higher breakdown electric field, and higher thermal conductivity, which promotes higher switching frequencies for high power applications, higher temperature operation, and results in higher power density devices relative to Si [1]. The proposed work is focused on design of a SiC gate driver to drive a SiC power MOSFET, on a Cree SiC process, with rise/fall times (less than 100 ns) suitable for 500 kHz to 1 MHz switching frequency applications. A process optimized gate driver topology design which is significantly different from generic Si circuit design is proposed. The ultimate goal of the project is to integrate this gate driver into a Toyota Prius plug-in hybrid electric vehicle (PHEV) charger module. The application of this high frequency charger will result in lighter, smaller, cheaper, and a more efficient power electronics system.

  4. A high-capacity steganography scheme for JPEG2000 baseline system.

    Science.gov (United States)

    Zhang, Liang; Wang, Haili; Wu, Renbiao

    2009-08-01

    Hiding capacity is very important for efficient covert communications. For JPEG2000 compressed images, it is necessary to enlarge the hiding capacity because the available redundancy is very limited. In addition, the bitstream truncation makes it difficult to hide information. In this paper, a high-capacity steganography scheme is proposed for the JPEG2000 baseline system, which uses bit-plane encoding procedure twice to solve the problem due to bitstream truncation. Moreover, embedding points and their intensity are determined in a well defined quantitative manner via redundancy evaluation to increase hiding capacity. The redundancy is measured by bit, which is different from conventional methods which adjust the embedding intensity by multiplying a visual masking factor. High volumetric data is embedded into bit-planes as low as possible to keep message integrality, but at the cost of an extra bit-plane encoding procedure and slightly changed compression ratio. The proposed method can be easily integrated into the JPEG2000 image coder, and the produced stego-bitstream can be decoded normally. Simulation shows that the proposed method is feasible, effective, and secure.

  5. Investigation of High-k Dielectrics and Metal Gate Electrodes for Non-volatile Memory Applications

    Science.gov (United States)

    Jayanti, Srikant

    Due to the increasing demand of non-volatile flash memories in the portable electronics, the device structures need to be scaled down drastically. However, the scalability of traditional floating gate structures beyond 20 nm NAND flash technology node is uncertain. In this regard, the use of metal gates and high-k dielectrics as the gate and interpoly dielectrics respectively, seem to be promising substitutes in order to continue the flash scaling beyond 20nm. Furthermore, research of novel memory structures to overcome the scaling challenges need to be explored. Through this work, the use of high-k dielectrics as IPDs in a memory structure has been studied. For this purpose, IPD process optimization and barrier engineering were explored to determine and improve the memory performance. Specifically, the concept of high-k / low-k barrier engineering was studied in corroboration with simulations. In addition, a novel memory structure comprising a continuous metal floating gate was investigated in combination with high-k blocking oxides. Integration of thin metal FGs and high-k dielectrics into a dual floating gate memory structure to result in both volatile and non-volatile modes of operation has been demonstrated, for plausible application in future unified memory architectures. The electrical characterization was performed on simple MIS/MIM and memory capacitors, fabricated through CMOS compatible processes. Various analytical characterization techniques were done to gain more insight into the material behavior of the layers in the device structure. In the first part of this study, interfacial engineering was investigated by exploring La2O3 as SiO2 scavenging layer. Through the silicate formation, the consumption of low-k SiO2 was controlled and resulted in a significant improvement in dielectric leakage. The performance improvement was also gauged through memory capacitors. In the second part of the study, a novel memory structure consisting of continuous metal FG

  6. Analysis of high-k spacer on symmetric underlap DG-MOSFET with Gate Stack architecture

    Science.gov (United States)

    Das, Rahul; Chakraborty, Shramana; Dasgupta, Arpan; Dutta, Arka; Kundu, Atanu; Sarkar, Chandan K.

    2016-09-01

    This paper shows the systematic study of underlap double gate (U-DG) NMOSFETs with Gate Stack (GS) under the influence of high-k spacers. In highly scaled devices, underlap is used at the Source and Drain side so as to reduce the short channel effects (SCE's), however, it significantly reduces the on current due to the increased channel resistance. To overcome these drawbacks, the use of high-k spacers is projected as one of the remedies. In this paper, the analog performance of the devices is studied on the basis of parameters like transconductance (gm), transconductance generation factor (gm/Id) and intrinsic gain (gmro). The RF performance is analyzed on the merits of intrinsic capacitance (Cgd, Cgs), resistance (Rgd, Rgs), transport delay (τm), inductance (Lsd), cutoff frequency (fT), and the maximum frequency of oscillation (fmax). The circuit performance of the devices are studied by implementing the device as the driver MOSFET in a Single Stage Common Source Amplifier. The Gain Bandwidth Product (GBW) has been analyzed from the frequency response of the circuit.

  7. Optimum air-demand ratio for maximum aeration efficiency in high-head gated circular conduits.

    Science.gov (United States)

    Ozkan, Fahri; Tuna, M Cihat; Baylar, Ahmet; Ozturk, Mualla

    2014-01-01

    Oxygen is an important component of water quality and its ability to sustain life. Water aeration is the process of introducing air into a body of water to increase its oxygen saturation. Water aeration can be accomplished in a variety of ways, for instance, closed-conduit aeration. High-speed flow in a closed conduit involves air-water mixture flow. The air flow results from the subatmospheric pressure downstream of the gate. The air entrained by the high-speed flow is supplied by the air vent. The air entrained into the flow in the form of a large number of bubbles accelerates oxygen transfer and hence also increases aeration efficiency. In the present work, the optimum air-demand ratio for maximum aeration efficiency in high-head gated circular conduits was studied experimentally. Results showed that aeration efficiency increased with the air-demand ratio to a certain point and then aeration efficiency did not change with a further increase of the air-demand ratio. Thus, there was an optimum value for the air-demand ratio, depending on the Froude number, which provides maximum aeration efficiency. Furthermore, a design formula for aeration efficiency was presented relating aeration efficiency to the air-demand ratio and Froude number.

  8. Isolated photosystem I reaction centers on a functionalized gated high electron mobility transistor.

    Science.gov (United States)

    Eliza, Sazia A; Lee, Ida; Tulip, Fahmida S; Mostafa, Salwa; Greenbaum, Elias; Ericson, M Nance; Islam, Syed K

    2011-09-01

    In oxygenic plants, photons are captured with high quantum efficiency by two specialized reaction centers (RC) called Photosystem I (PS I) and Photosystem II (PS II). The captured photon triggers rapid charge separation and the photon energy is converted into an electrostatic potential across the nanometer-scale (~6 nm) reaction centers. The exogenous photovoltages from a single PS I RC have been previously measured using the technique of Kelvin force probe microscopy (KFM). However, biomolecular photovoltaic applications require two-terminal devices. This paper presents for the first time, a micro-device for detection and characterization of isolated PS I RCs. The device is based on an AlGaN/GaN high electron mobility transistor (HEMT) structure. AlGaN/GaN HEMTs show high current throughputs and greater sensitivity to surface charges compared to other field-effect devices. PS I complexes immobilized on the floating gate of AlGaN/GaN HEMTs resulted in significant changes in the device characteristics under illumination. An analytical model has been developed to estimate the RCs of a major orientation on the functionalized gate surface of the HEMTs.

  9. AlGaN/GaN high electron mobility transistors with selective area grown p-GaN gates

    Science.gov (United States)

    Yuliang, Huang; Lian, Zhang; Zhe, Cheng; Yun, Zhang; Yujie, Ai; Yongbing, Zhao; Hongxi, Lu; Junxi, Wang; Jinmin, Li

    2016-11-01

    We report a selective area growth (SAG) method to define the p-GaN gate of AlGaN/GaN high electron mobility transistors (HEMTs) by metal-organic chemical vapor deposition. Compared with Schottky gate HEMTs, the SAG p-GaN gate HEMTs show more positive threshold voltage (V th) and better gate control ability. The influence of Cp2Mg flux of SAG p-GaN gate on the AlGaN/GaN HEMTs has also been studied. With the increasing Cp2Mg from 0.16 μmol/min to 0.20 μmol/min, the V th raises from -0.67 V to -0.37 V. The maximum transconductance of the SAG HEMT at a drain voltage of 10 V is 113.9 mS/mm while that value of the Schottky HEMT is 51.6 mS/mm. The SAG method paves a promising way for achieving p-GaN gate normally-off AlGaN/GaN HEMTs without dry etching damage. Project supported by the National Natural Sciences Foundation of China (Nos. 61376090, 61306008) and the National High Technology Program of China (No. 2014AA032606).

  10. Baseline measures for net-proton distributions in high energy heavy-ion collisions

    Science.gov (United States)

    Netrakanti, P. K.; Luo, X. F.; Mishra, D. K.; Mohanty, B.; Mohanty, A.; Xu, N.

    2016-03-01

    We report a systematic comparison of the recently measured cumulants of the net-proton distributions for 0-5% central Au + Au collisions in the first phase of the Beam Energy Scan (BES) Program at the Relativistic Heavy Collider facility to various kinds of possible baseline measures. These baseline measures correspond to an assumption that the proton and anti-proton distributions follow Poisson statistics, Binomial statistics, obtained from a transport model calculation and from a hadron resonance gas model. The higher order cumulant net-proton data for the center of mass energies (√{sNN}) of 19.6 and 27 GeV are observed to deviate from most of the baseline measures studied. The deviations are predominantly due to the difference in shape of the proton distributions between data and those obtained in the baseline measures. We also present a detailed study on the relevance of the independent production approach as a baseline for comparison with the measurements at various beam energies. Our studies point to the need of either more detailed baseline models for the experimental measurements or a description via QCD calculations in order to extract the exact physics process that leads to deviation of the data from the baselines presented.

  11. Experimental investigations of aeration efficiency in high-head gated circular conduits.

    Science.gov (United States)

    Cihat Tuna, M; Ozkan, Fahri; Baylar, Ahmet

    2014-01-01

    The primary purpose of water aeration is to increase the oxygen saturation of the water. This can be achieved by using hydraulic structures because of substantial air bubble entrainment at these structures. Closed conduit aeration is a particular instance of this. While there has been a great deal of research on air-demand ratio within closed conduit, very little research has specifically addressed aeration efficiency of closed conduit. In the present work an experimental study was conducted to investigate the aeration efficiency of high-head gated circular conduits. Results showed that high-head gated circular conduits were effective for oxygen transfer. The effects of Froude number and ratio of the water cross-sectional flow area to the conduit cross-sectional area on aeration efficiency were particularly significant, whereas the effect of conduit length was only moderate. Further, a design formula for the aeration efficiency was presented relating the aeration efficiency to ratio of water cross-sectional flow area to conduit cross-sectional area and Froude number. The obtained results will be useful in future modeling processes and aid the practicing engineer in predicting aeration efficiency for design purposes.

  12. Aharonov-Bohm interference in gate-defined ring of high-mobility graphene

    Science.gov (United States)

    Kim, Minsoo; Lee, Hu-Jong

    2015-03-01

    Recent progress in preparing a high-quality graphene layer enables one to investigate the intrinsic carrier transport nature in the material. Here, we report the signature of conservation of the Berry's phase with preserved valley symmetry in Aharonov-Bohm (AB) interferometers fabricated on monolayer graphene with high carrier mobility, where the graphene was sandwiched between two thin hexagonal boron nitride (h-BN) layers. In measurements, charge carriers were confined in an AB ring-shaped potential well formed by the dual-gate operation of the bottom and top gates and the four-terminal magneto-conductance (MC) was measured with varying charge carrier density and temperature. Graphene in the device was in the ballistic regime as confirmed by the conductance quantization in steps of ΔG = 4e2/ h in a constricted conducting channel of separate measurements. We observed h/e periodic modulation of MC and the zero-field conductance minimum with a negative MC background. The phase information of AB interference strongly suggests that carriers in the graphene in our devices preserve the intrinsic Dirac transport nature, which would be conveniently utilized for valleytronics in graphene.

  13. A First Baseline for the Magnets in the High Luminosity LHC Insertion Regions

    CERN Document Server

    Todesco, E; Ambrosio, G; Arduini, G; Cerutti, F; De Maria, R; Esposito, L; Fartoukh, S; Ferracin, P; Felice, H; Gupta, R; Kersevan, R; Mokhov, N; Nakamoto, T; Rakno, I; Rifflet, J M; Rossi, L; Sabbi, G L; Segreti, M; Toral, F; Xu, Q; Wanderer, P; van Weelderen, R

    2014-01-01

    The High Luminosity LHC (HL-LHC) project aims at accumulating 3000 fb-1 in the years 2023-2035, i.e. ten times more w.r.t. the nominal LHC performance expected for 2010- 2021. One key element to reach this challenging performance is a new insertion region to reduce the beam size in the interaction point by approximately a factor two. This requires larger aperture magnets in the region spanning from the interaction point to the matching section quadrupoles. This aperture has been fixed to 150 mm for the inner triplet quadrupoles in 2012. In this paper we give a first baseline of the interaction region. We discuss the main motivations that lead us to choose the technology, the combination of fields/gradients and lengths, the apertures, the quantity of superconductor, and the operational margin. Key elements are also the constraints given by the energy deposition in terms of heat load and radiation damage; we present the main features related to shielding and heat removal.

  14. Attention-Deficit Hyperactivity Disorder Status and Baseline Neurocognitive Performance in High School Athletes.

    Science.gov (United States)

    Salinas, Christine M; Dean, Preston; LoGalbo, Anthony; Dougherty, Michael; Field, Melvin; Webbe, Frank M

    2016-01-01

    Approximately 136,000 concussions occur annually in American high school sports. Neuropsychological data indicate that children with preexisting cognitive difficulties, such as attention-deficit hyperactivity disorder (ADHD), may have protracted recovery from concussion. ADHD, with an estimated prevalence of 11% in youth, may increase an athlete's vulnerability to sustaining sports-related traumatic brain injury (TBI). The preponderance of evidence focusing on TBI and ADHD has derived from motor vehicle accidents rather than sports-related incidents. Thus, it is paramount to explore how ADHD may relate to injury in the sports concussion context, as well as to assess how ADHD may affect baseline neurocognitive testing. Adolescent athletes with ADHD (n = 256) demonstrated significantly reduced Verbal Memory, Visual Motor, and Impulse Control index scores compared with their peers without ADHD (n = 256). Athletes with ADHD were nearly twice as likely to have sustained a prior concussion (ADHD, 14.1%; non-ADHD, 7.8%). Knowledge regarding the unique neurocognitive profile of athletes with ADHD may enhance clinical management decisions.

  15. Nanocomposites of polyimide and mixed oxide nanoparticles for high performance nanohybrid gate dielectrics in flexible thin film transistors

    Science.gov (United States)

    Kim, Ju Hyun; Hwang, Byeong-Ung; Kim, Do-Il; Kim, Jin Soo; Seol, Young Gug; Kim, Tae Woong; Lee, Nae-Eung

    2017-01-01

    Organic gate dielectrics in thin film transistors (TFTs) for flexible display have advantages of high flexibility yet have the disadvantage of low dielectric constant (low-k). To supplement low-k characteristics of organic gate dielectrics, an organic/inorganic nanocomposite insulator loaded with high-k inorganic oxide nanoparticles (NPs) has been investigated but high loading of high-k NPs in polymer matrix is essential. Herein, compositing of over-coated polyimide (PI) on self-assembled (SA) layer of mixed HfO2 and ZrO2 NPs as inorganic fillers was used to make dielectric constant higher and leakage characteristics lower. A flexible TFT with lower the threshold voltage and high current on/off ratio could be fabricated by using the hybrid gate dielectric structure of the nanocomposite with SA layer of mixed NPs on ultrathin atomic-layer deposited Al2O3.

  16. High Frequency Very Long Baseline Interferometry Observations of Active Galactic Nuclei

    Science.gov (United States)

    Bower, Geoffrey Copeland

    Millimeter wavelength very long baseline interferometry (VLBI) provides an excellent tool for the investigation of compact synchrotron sources. The high angular resolution and the decline in synchrotron opacity and lifetime with decreasing wavelength give unprecedented spatial and temporal resolution in active galactic nuclei. We present here a description of the implementation of millimeter VLBI with the 9-element millimeter array at Hat Creek Radio Observatory. We emphasize the technical details of array phasing, calibration and observation. The Hat Creek array was used successfully in 5 VLBI experiments between 1995 and 1997. We tested the technique of total power correction for atmospheric phase fluctuations due to water vapor with two epochs of 3mm λ VLBI observations with the Hat Creek array and with the National Radio Astronomy Observatory (NRAO) Kitt Peak 12m antenna. We reduced the root-mean-square phase by as much as a factor of two and to as low as one radian. The limiting factor was the gain stability of the receivers. We present 7mm λ VLBI observations made with the NRAO Very Long Baseline Array (VLBA) of the compact, nonthermal radio source Sgr A*. We find that the image of Sgr A* is fully consistent with the hypothesis that it is a cyclo-synchrotron source powered by accretion onto a 106Msolar black hole and obscured by a screen of thermal electrons. We find no evidence for any asymmetric structure. We also present a two year study of the gamma-ray blazar 530 with multiple epochs of VLBI imaging at 3 mm, 7 mm, 1.3 cm and 3.6 cm λ. We incorporate flux density monitoring ranging from the radio band to positive correlation over 4 years between the millimeter and gamma-ray flux densities. We also find that a bright millimeter wavelength flare in early 1995 corresponded to the creation of a new parsec-scale jet component. We study the spectra and dynamical evolution of the jet. The jet component appears to decelerate from 7.6 ± 2.2c to 0.95 ± 0.16c

  17. Low Temperature Deposition of High-k/Metal Gate Stacks on High-Sn Content (Si)GeSn-Alloys

    OpenAIRE

    Schulte-Braucks, C; Von Den Driesch, N; Glass, S; Tiedemann, AT; Breuer, U; Besmehn, A; Hartmann, JM; Ikonic, Z; Zhao, QT; Mantl, S; Buca, D.

    2016-01-01

    (Si)GeSn is an emerging group IV alloy system offering new exciting properties, with great potential for low power electronics due to the fundamental direct band gap and prospects as high mobility material. In this Article, we present a systematic study of HfO2/TaN high-k/metal gate stacks on (Si)GeSn ternary alloys and low temperature processes for large scale integration of Sn based alloys. Our investigations indicate that SiGeSn ternaries show enhanced thermal stability compared to GeSn bi...

  18. Semiconductor/Piezoelectrics Hybrid Heterostructures with Highly Effective Gate-Tunable Electrotransport and Magnetic Behaviors.

    Science.gov (United States)

    Chen, Lei; Zhao, Wei-Yao; Wang, Jing; Gao, Guan-Yin; Zhang, Jin-Xing; Wang, Yu; Li, Xiao-Min; Cao, Shi-Xun; Li, Xiao-Guang; Luo, Hao-Su; Zheng, Ren-Kui

    2016-10-12

    We report the epitaxial growth of oxygen deficient titanium dioxide thin films on 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 (PMN-PT) single crystals and realized highly effective in situ electrostatic manipulation of electrotransport and magnetism of TiO2-δ films via gate voltages. Upon the polarization switching in the PMN-PT, the carrier density of the TiO2-δ film could be reversibly modified, resulting in a large nonvolatile resistivity modulation by ∼51% at T = 300 K, approximately 4-12 times larger than that of other transition-metal oxide film/PMN-PT structures. By taking advantage of in situ manipulation of the carrier density via gate voltages, we found that competition between the trap of electrons by the Ti(3+)-VO pairs and that by the positive polarization charges at the interface results in a significant resistivity relaxation upon the polarization switching, and revealed that magnetization is inversely correlated with the carrier density of the TiO2-δ film. Such hybrid structures combining materials with dissimilar functionalities may have potential applications in multifunctional devices which can take advantage of the useful and unique properties of both materials.

  19. Design of High-Performance Asynchronous Pipeline Using Synchronizing Logic Gates

    Science.gov (United States)

    Xia, Zhengfan; Ishihara, Shota; Hariyama, Masanori; Kameyama, Michitaka

    This paper introduces a novel design method of an asynchronous pipeline based on dual-rail dynamic logic. The overhead of handshake control logic is greatly reduced by constructing a reliable critical datapath, which offers the pipeline high throughput as well as low power consumption. Synchronizing Logic Gates (SLGs), which have no data dependency problem, are used in the design to construct the reliable critical datapath. The design targets latch-free and extremely fine-grain or gate-level pipeline, where the depth of every pipeline stage is only one dual-rail dynamic logic. HSPICE simulation results, in a 65nm design technology, indicate that the proposed design increases the throughput by 120% and decreases the power consumption by 54% compared with PS0, a classic dual-rail asynchronous pipeline implementation style, in 4-bit wide FIFOs. Moreover, this method is applied to design an array style multiplier. It shows that the proposed design reduces power by 37.9% compared to classic synchronous design when the workloads are 55%. A chip has been fabricated with a 4×4 multiplier function, which works well at 2.16G data-set/s (Post-layout simulation).

  20. High-Contrast Visualization of Upconversion Luminescence in Mice Using Time-Gating Approach.

    Science.gov (United States)

    Zheng, Xianlin; Zhu, Xingjun; Lu, Yiqing; Zhao, Jiangbo; Feng, Wei; Jia, Guohua; Wang, Fan; Li, Fuyou; Jin, Dayong

    2016-04-01

    Optical imaging through the near-infrared (NIR) window provides deep penetration of light up to several centimeters into biological tissues. Capable of emitting 800 nm luminescence under 980 nm illumination, the recently developed upconversion nanoparticles (UCNPs) suggest a promising optical contrast agent for in vivo bioimaging. However, presently they require high-power lasers to excite when applied to small animals, leading to significant scattering background that limits the detection sensitivity as well as a detrimental thermal effect. In this work, we show that the time-gating approach implementing pulsed illumination from a NIR diode laser and time-delayed imaging synchronized via an optical chopper offers detection sensitivity more than 1 order of magnitude higher than the conventional approach using optical band-pass filters (S/N, 47321/6353 vs 5339/58), when imaging UCNPs injected into Kunming mice. The pulsed laser illumination (70 μs ON in 200 μs period) also reduces the overall thermal accumulation to 35% of that under the continuous-wave mode. Technical details are given on setting up the time-gating unit comprising an optical chopper, a pinhole, and a microscopy eyepiece. Being generally compatible with any camera, this provides a convenient and low cost solution to NIR animal imaging using UCNPs as well as other luminescent probes.

  1. Realization of an 850V High Voltage Half Bridge Gate Drive IC with a New NFFP HVI Structure

    Institute of Scientific and Technical Information of China (English)

    Ming Qiao; Hong-Jie Wang; Ming-Wei Duan; Jian Fang; Bo Zhang; Zhao-Ji Li

    2007-01-01

    A NFFP HVI structure which implements high breakdown voltage without using additional FFP and process steps is proposed in this paper. An 850 V high voltage half bridge gate drive IC with the NFFP HVI structure is experimentally realized using a thin epitaxial BCD process. Compared with the MFFP HVI structure,the proposed NFFP HVI structure shows simpler process and lower cost. The high side offset voltage in the half bridge gate drive IC with the NFFP HVI structure is almost as same as that with the selfshielding structure.

  2. Comparison of recessed gate-head structures on normally-off AlGaN/GaN high-electron-mobility transistor performance.

    Science.gov (United States)

    Khan, Mansoor Ali; Heo, Jun-Woo; Kim, Hyun-Seok; Park, Hyun-Chang

    2014-11-01

    In this work, different gate-head structures have been compared in the context of AlGaN/GaN-based high-electron-mobility transistors (HEMTs). Field-plate (FP) technology self-aligned to the gate electrode leads to various gate-head structures, most likely gamma (γF)-gate, camel (see symbol)-gate, and mushroom-shaped (T)-gate. In-depth comparison of recessed gate-head structures demonstrated that key performance metrics such as transconductance, output current, and breakdown voltage are better with the T-gate head structure. The recessed T-gate with its one arm toward the source side not only reduces the source-access resistance (R(g) +R(gs)), but also minimizes the source-side dispersion and current leakage, resulting in high transconductance (G(m)) and output current (I(DS)). At the same time, the other arm toward the drain-side reduces the drain-side dispersion and tends to distribute electric field peaks uniformly, resulting in high breakdown voltage (V(BR)). DC and RF analysis showed that the recessed T-gate FP-HEMT is a suitable candidate not only for high-frequency operation, but also for high-power applications.

  3. Performance Analysis of Modified Drain Gating Techniques for Low Power and High Speed Arithmetic Circuits

    Directory of Open Access Journals (Sweden)

    Shikha Panwar

    2014-01-01

    Full Text Available This paper presents several high performance and low power techniques for CMOS circuits. In these design methodologies, drain gating technique and its variations are modified by adding an additional NMOS sleep transistor at the output node which helps in faster discharge and thereby providing higher speed. In order to achieve high performance, the proposed design techniques trade power for performance in the delay critical sections of the circuit. Intensive simulations are performed using Cadence Virtuoso in a 45 nm standard CMOS technology at room temperature with supply voltage of 1.2 V. Comparative analysis of the present circuits with standard CMOS circuits shows smaller propagation delay and lesser power consumption.

  4. High Grade Glioma Mimicking Voltage Gated Potassium Channel Complex Associated Antibody Limbic Encephalitis

    Directory of Open Access Journals (Sweden)

    Dilan Athauda

    2014-01-01

    Full Text Available Though raised titres of voltage gated potassium channel (VGKC complex antibodies have been occasionally associated with extracranial tumours, mainly presenting as Morvan's Syndrome or neuromyotonia, they have not yet been reported to be associated with an intracranial malignancy. This is especially important as misdiagnosis of these conditions and delay of the appropriate treatment can have important prognostic implications. We describe a patient with a high grade glioma presenting with clinical, radiological, and serological features consistent with the diagnosis of VGKC antibody associated limbic encephalitis (LE. This is the first association between a primary brain tumour and high titre of VGKC complex antibodies. Clinicoradiological progression despite effective immunosuppressive treatment should prompt clinicians to look for alternative diagnoses. Further studies to elucidate a possible association between VGKC complex and other surface antigen antibodies with primary brain tumours should be carried out.

  5. High grade glioma mimicking voltage gated potassium channel complex associated antibody limbic encephalitis.

    Science.gov (United States)

    Athauda, Dilan; Delamont, R S; Pablo-Fernandez, E De

    2014-01-01

    Though raised titres of voltage gated potassium channel (VGKC) complex antibodies have been occasionally associated with extracranial tumours, mainly presenting as Morvan's Syndrome or neuromyotonia, they have not yet been reported to be associated with an intracranial malignancy. This is especially important as misdiagnosis of these conditions and delay of the appropriate treatment can have important prognostic implications. We describe a patient with a high grade glioma presenting with clinical, radiological, and serological features consistent with the diagnosis of VGKC antibody associated limbic encephalitis (LE). This is the first association between a primary brain tumour and high titre of VGKC complex antibodies. Clinicoradiological progression despite effective immunosuppressive treatment should prompt clinicians to look for alternative diagnoses. Further studies to elucidate a possible association between VGKC complex and other surface antigen antibodies with primary brain tumours should be carried out.

  6. A two-dimensional threshold voltage analytical model for metal-gate/high-k/SiO2/Si stacked MOSFETs

    Institute of Scientific and Technical Information of China (English)

    Ma Fei; Liu Hong-Xia; Fan Ji-Bin; Wang Shu-Long

    2012-01-01

    In this paper the influences of the metal-gate and high-k/SiO2/Si stacked structure on the metal-oxidesemiconductor field-effect transistor (MOSFET) axe investigated.The flat-band voltage is revised by considering the influences of stacked structure and metal-semiconductor work function fluctuation. The two-dimensional Poisson's equation of potential distribution is presented.A threshold voltage analytical model for metal-gate/high-k/SiO2/Si stacked MOSFETs is developed by solving these Poisson's equations using the boundary conditions.The model is verified by a two-dimensional device simulator,which provides the basic design guidance for metal-gate/high-k/SiO2/Si stacked MOSFETs.

  7. Electrolyte gate dependent high-frequency measurement of graphene field-effect transistor for sensing applications

    OpenAIRE

    Fu, W.; El Abbassi, M.; Hasler, T.; M. Jung; M. Steinacher; Calame, M.; Schönenberger,C.; Puebla-Hellmann, G.; Hellmüller, S.; T. Ihn; Wallraff, A.

    2014-01-01

    We performed radiofrequency (RF) reflectometry measurements at 2.4 GHz on electrolyte-gated graphene field-effect transistors (GFETs) utilizing a tunable stub-matching circuit for impedance matching. We demonstrate that the gate voltage dependent RF resistivity of graphene can be deduced even in the presence of the electrolyte which is in direct contact with the graphene layer. The RF resistivity is found to be consistent with its DC counterpart in the full gate voltage range. Furthermore, in...

  8. Enhancement mode AlGaN/GaN MOS high-electron-mobility transistors with ZrO2 gate dielectric deposited by atomic layer deposition

    Science.gov (United States)

    Anderson, Travis J.; Wheeler, Virginia D.; Shahin, David I.; Tadjer, Marko J.; Koehler, Andrew D.; Hobart, Karl D.; Christou, Aris; Kub, Francis J.; Eddy, Charles R., Jr.

    2016-07-01

    Advanced applications of AlGaN/GaN high-electron-mobility transistors (HEMTs) in high-power RF and power switching are driving the need for insulated gate technology. We present a metal-oxide-semiconductor (MOS) gate structure using atomic-layer-deposited ZrO2 as a high-k, high-breakdown gate dielectric for reduced gate leakage and a recessed barrier structure for enhancement mode operation. Compared to a Schottky metal-gate HEMT, the recessed MOS-HEMT structure demonstrated a reduction in the gate leakage current by 4 orders of magnitude and a threshold voltage shift of +6 V to a record +3.99 V, enabled by a combination of a recessed barrier structure and negative oxide charge.

  9. High precision electric gate for time-of-flight ion mass spectrometers

    Science.gov (United States)

    Sittler, Edward C. (Inventor)

    2011-01-01

    A time-of-flight mass spectrometer having a chamber with electrodes to generate an electric field in the chamber and electric gating for allowing ions with a predetermined mass and velocity into the electric field. The design uses a row of very thin parallel aligned wires that are pulsed in sequence so the ion can pass through the gap of two parallel plates, which are biased to prevent passage of the ion. This design by itself can provide a high mass resolution capability and a very precise start pulse for an ion mass spectrometer. Furthermore, the ion will only pass through the chamber if it is within a wire diameter of the first wire when it is pulsed and has the right speed so it is near all other wires when they are pulsed.

  10. Interface Study on Amorphous Indium Gallium Zinc Oxide Thin Film Transistors Using High-k Gate Dielectric Materials

    Directory of Open Access Journals (Sweden)

    Yu-Hsien Lin

    2015-01-01

    Full Text Available We investigated amorphous indium gallium zinc oxide (a-IGZO thin film transistors (TFTs using different high-k gate dielectric materials such as silicon nitride (Si3N4 and aluminum oxide (Al2O3 at low temperature process (<300°C and compared them with low temperature silicon dioxide (SiO2. The IGZO device with high-k gate dielectric material will expect to get high gate capacitance density to induce large amount of channel carrier and generate the higher drive current. In addition, for the integrating process of integrating IGZO device, postannealing treatment is an essential process for completing the process. The chemical reaction of the high-k/IGZO interface due to heat formation in high-k/IGZO materials results in reliability issue. We also used the voltage stress for testing the reliability for the device with different high-k gate dielectric materials and explained the interface effect by charge band diagram.

  11. High-Performance Deep SubMicron CMOS Technologies with Polycrystalline-SiGe Gates

    NARCIS (Netherlands)

    Ponomarev, Youri V.; Stolk, Peter A.; Salm, Cora; Schmitz, Jurriaan; Woerlee, P.H.

    2000-01-01

    The use of polycrystalline SiGe as the gate material for deep submicron CMOS has been investigated. A complete compatibility to standard CMOS processing is demonstrated when polycrystalline Si is substituted with SiGe (for Ge fractions below 0.5) to form the gate electrode of the transistors. Perfor

  12. High-Performance Deep SubMicron CMOS Technologies with Polycrystalline-SiGe Gates

    NARCIS (Netherlands)

    Ponomarev, Youri V.; Stolk, Peter A.; Salm, Cora; Schmitz, Jurriaan; Woerlee, P.H.

    2000-01-01

    The use of polycrystalline SiGe as the gate material for deep submicron CMOS has been investigated. A complete compatibility to standard CMOS processing is demonstrated when polycrystalline Si is substituted with SiGe (for Ge fractions below 0.5) to form the gate electrode of the transistors.

  13. Low-Temperature Solution-Processed Gate Dielectrics for High-Performance Organic Thin Film Transistors

    Directory of Open Access Journals (Sweden)

    Jaekyun Kim

    2015-10-01

    Full Text Available A low-temperature solution-processed high-k gate dielectric layer for use in a high-performance solution-processed semiconducting polymer organic thin-film transistor (OTFT was demonstrated. Photochemical activation of sol-gel-derived AlOx films under 150 °C permitted the formation of a dense film with low leakage and relatively high dielectric-permittivity characteristics, which are almost comparable to the results yielded by the conventionally used vacuum deposition and high temperature annealing method. Octadecylphosphonic acid (ODPA self-assembled monolayer (SAM treatment of the AlOx was employed in order to realize high-performance (>0.4 cm2/Vs saturation mobility and low-operation-voltage (<5 V diketopyrrolopyrrole (DPP-based OTFTs on an ultra-thin polyimide film (3-μm thick. Thus, low-temperature photochemically-annealed solution-processed AlOx film with SAM layer is an attractive candidate as a dielectric-layer for use in high-performance organic TFTs operated at low voltages.

  14. Designing High-Fidelity Single-Shot Three-Qubit Gates: A Machine-Learning Approach

    Science.gov (United States)

    Zahedinejad, Ehsan; Ghosh, Joydip; Sanders, Barry C.

    2016-11-01

    Three-qubit quantum gates are key ingredients for quantum error correction and quantum-information processing. We generate quantum-control procedures to design three types of three-qubit gates, namely Toffoli, controlled-not-not, and Fredkin gates. The design procedures are applicable to a system comprising three nearest-neighbor-coupled superconducting artificial atoms. For each three-qubit gate, the numerical simulation of the proposed scheme achieves 99.9% fidelity, which is an accepted threshold fidelity for fault-tolerant quantum computing. We test our procedure in the presence of decoherence-induced noise and show its robustness against random external noise generated by the control electronics. The three-qubit gates are designed via the machine-learning algorithm called subspace-selective self-adaptive differential evolution.

  15. High-fidelity gate operations for quantum computing beyond dephasing time limits

    Science.gov (United States)

    Souza, Alexandre M.; Sarthour, Roberto S.; Oliveira, Ivan S.; Suter, Dieter

    2015-12-01

    The implementation of quantum gates with fidelities that exceed the threshold for reliable quantum computing requires robust gates whose performance is not limited by the precision of the available control fields. The performance of these gates also should not be affected by the noisy environment of the quantum register. Here we use randomized benchmarking of quantum gate operations to compare the performance of different families of gates that compensate errors in the control field amplitudes and decouple the system from the environmental noise. We obtain average fidelities of up to 99.8%, which exceeds the threshold value for some quantum error correction schemes as well as the expected limit from the dephasing induced by the environment.

  16. High-temperature single-layer SQUID gradiometers with long baseline and parasitic effective area compensation

    Energy Technology Data Exchange (ETDEWEB)

    Pegrum, C.M.; Eulenburg, A.; Romans, E.J.; Carr, C.; Millar, A.J.; Donaldson, G.B. [Department of Physics and Applied Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom)

    1999-11-01

    First-order HTS SQUID gradiometers were fabricated on 30x10 mm{sup 2} bicrystal substrates. These devices have a baseline of 13 mm, intrinsic balance levels of {approx}1/700 and a typical gradient sensitivity at 1 kHz of 79 fT cm{sup -1}Hz{sup -1/2}. A two-SQUID coupling scheme is discussed that further enhances the device's ability to reject uniform fields. (author)

  17. Fast, high-fidelity, all-optical and dynamically-controlled polarization gate using room-temperature atomic vapor

    Science.gov (United States)

    Li, Runbing; Zhu, Chengjie; Deng, L.; Hagley, E. W.

    2014-10-01

    We demonstrate a fast, all-optical polarization gate in a room-temperature atomic medium. Using a Polarization-Selective-Kerr-Phase-Shift (PSKPS) technique, we selectively write a π phase shift to one circularly-polarized component of a linearly-polarized input signal field. The output signal field maintains its original strength but acquires a 90° linear polarization rotation, demonstrating fast, high-fidelity, dynamically-controlled polarization gate operation. The intensity of the polarization-switching field used in this PKSPK-based polarization gate operation is only 2 mW/cm2, which would be equivalent to 0.5 nW of light power (λ = 800 nm) confined in a typical commercial photonic hollow-core fiber. This development opens a realm of possibilities for potential future extremely low light level telecommunication and information processing systems.

  18. Efficient generation of high beam-quality attosecond pulse with polarization-gating Bessel-Gauss beam from highly-ionized media.

    Science.gov (United States)

    Li, Yang; Zhang, Qingbin; Hong, Weiyi; Wang, Shaoyi; Wang, Zhe; Lu, Peixiang

    2012-07-02

    Single attosecond pulse generation with polarization gating Bessel-Gauss beam in relatively strongly-ionized media is investigated. The results show that Bessel-Gauss beam has the ability to suppress the spatial plasma dispersion effects caused by high density of free electrons, thus the laser field can maintain its spatial profile through highly-ionized medium. This indicates the use of Bessel-Gauss beam has advantages over Gaussian beam in high harmonic generation under high ionization conditions. In our scheme, significant improvement of spatiotemporal properties of harmonics is achieved and an isolated attosecond pulse with high beam quality is filtered out using polarization gating.

  19. High-density carrier-accumulated and electrically stable oxide thin-film transistors from ion-gel gate dielectric

    Science.gov (United States)

    Fujii, Mami N.; Ishikawa, Yasuaki; Miwa, Kazumoto; Okada, Hiromi; Uraoka, Yukiharu; Ono, Shimpei

    2015-12-01

    The use of indium-gallium-zinc oxide (IGZO) has paved the way for high-resolution uniform displays or integrated circuits with transparent and flexible devices. However, achieving highly reliable devices that use IGZO for low-temperature processes remains a technological challenge. We propose the use of IGZO thin-film transistors (TFTs) with an ionic-liquid gate dielectric in order to achieve high-density carrier-accumulated IGZO TFTs with high reliability, and we discuss a distinctive mechanism for the degradation of this organic-inorganic hybrid device under long-term electrical stress. Our results demonstrated that an ionic liquid or gel gate dielectric provides highly reliable and low-voltage operation with IGZO TFTs. Furthermore, high-density carrier accumulation helps improve the TFT characteristics and reliability, and it is highly relevant to the electronic phase control of oxide materials and the degradation mechanism for organic-inorganic hybrid devices.

  20. 基于PMOS三维选通高速门控技术%3D Range-Gated High Speed Gate-Control Technology Based on PMOS

    Institute of Scientific and Technical Information of China (English)

    杨金宝; 周燕; 范松涛; 曾华林; 王新伟

    2012-01-01

    为三维选通成像提供了纳秒级阴极选通高速门控开关的设计与实现.该门控开关创新性地采用互补级联开关的方式实现阴极正负电压的高速选通.结合功率开关管的特性,使用功率PMOS作为前级开关,产生平项质量好的正脉冲;采用功率三极管作为后级开关,无需额外驱动,通过二者互补级联的方式产生阴极选通负脉冲.实验表明,最终开关的上升沿时间为13.4 ns,下降沿时间为24.6ns,最小脉宽为50 ns,最高工作频率100 kHz,导通电压-200 V,关断电压40V,满足三维选通门控要求.门控开关通过互补级联方式,不但寄生参数小,脉冲上升、下降时间小,脉冲平顶质量好,时序控制精度高,无需隔离驱动,而且通过功率三极管作后级开关,可以获得比TTL触发脉冲更窄的脉宽,具有良好的脉宽特性.%Design and implementation of nanosecond high speed gate-control switch was required for 3D range-gated imaging. Complementary cascade was used to implement the high speed switch with negative and positive voltage. Power PMOS and power triode transistor were used according to the switch prosperities. Power PMOS was the front switch which produced a positive pulse with good flat-roofed quality, and power triode transistor was the rear one which didnt require extra driver. Through the complementary cascade of the two switches, cathode negative pulse was obtained. Experiments showed that the rising time and the falling time of the gate-control switch were 13.4 ns and 24.6 ns respectively. The narrowest pulse width was 50 ns and the highest frequency was as high as 100 kHz. The turn-on voltage of the switch was -200 V and the turn-off voltage was 40 V. All of these met the requirements of 3D range-gated imaging. Through complementary cascade switch, the rising and falling time of the pulse are small, and good flat-roofed quality is obtained. In addition, the switch has many advantages such as simple structure

  1. Ultimate Scaling of HighGate Dielectrics: Higher-κ or Interfacial Layer Scavenging?

    Directory of Open Access Journals (Sweden)

    Takashi Ando

    2012-03-01

    Full Text Available Current status and challenges of aggressive equivalent-oxide-thickness (EOT scaling of highgate dielectrics via higher-κ ( > 20 materials and interfacial layer (IL scavenging techniques are reviewed. La-based higher-κ materials show aggressive EOT scaling (0.5–0.8 nm, but with effective workfunction (EWF values suitable only for n-type field-effect-transistor (FET. Further exploration for p-type FET-compatible higher-κ materials is needed. Meanwhile, IL scavenging is a promising approach to extend Hf-based high-κ dielectrics to future nodes. Remote IL scavenging techniques enable EOT scaling below 0.5 nm. Mobility-EOT trends in the literature suggest that short-channel performance improvement is attainable with aggressive EOT scaling via IL scavenging or La-silicate formation. However, extreme IL scaling (e.g., zero-IL is accompanied by loss of EWF control and with severe penalty in reliability. Therefore, highly precise IL thickness control in an ultra-thin IL regime ( < 0.5 nm will be the key technology to satisfy both performance and reliability requirements for future CMOS devices.

  2. Investigation of high-k yttrium copper titanate thin films as alternative gate dielectrics

    Science.gov (United States)

    Grazia Monteduro, Anna; Ameer, Zoobia; Rizzato, Silvia; Martino, Maurizio; Caricato, Anna Paola; Tasco, Vittorianna; Chaitanya Lekshmi, Indira; Hazarika, Abhijit; Choudhury, Debraj; Sarma, D. D.; Maruccio, Giuseppe

    2016-10-01

    Nearly amorphous high-k yttrium copper titanate thin films deposited by laser ablation were investigated in both metal-oxide-semiconductor (MOS) and metal-insulator-metal (MIM) junctions in order to assess the potentialities of this material as a gate oxide. The trend of dielectric parameters with film deposition shows a wide tunability for the dielectric constant and AC conductivity, with a remarkably high dielectric constant value of up to 95 for the thick films and conductivity as low as 6  ×  10-10 S cm-1 for the thin films deposited at high oxygen pressure. The AC conductivity analysis points out a decrease in the conductivity, indicating the formation of a blocking interface layer, probably due to partial oxidation of the thin films during cool-down in an oxygen atmosphere. Topography and surface potential characterizations highlight differences in the thin film microstructure as a function of the deposition conditions; these differences seem to affect their electrical properties.

  3. Low Temperature Deposition of High-k/Metal Gate Stacks on High-Sn Content (Si)GeSn-Alloys.

    Science.gov (United States)

    Schulte-Braucks, C; von den Driesch, N; Glass, S; Tiedemann, A T; Breuer, U; Besmehn, A; Hartmann, J-M; Ikonic, Z; Zhao, Q T; Mantl, S; Buca, D

    2016-05-25

    (Si)GeSn is an emerging group IV alloy system offering new exciting properties, with great potential for low power electronics due to the fundamental direct band gap and prospects as high mobility material. In this Article, we present a systematic study of HfO2/TaN high-k/metal gate stacks on (Si)GeSn ternary alloys and low temperature processes for large scale integration of Sn based alloys. Our investigations indicate that SiGeSn ternaries show enhanced thermal stability compared to GeSn binaries, allowing the use of the existing Si technology. Despite the multielemental interface and large Sn content of up to 14 atom %, the HfO2/(Si)GeSn capacitors show small frequency dispersion and stretch-out. The formed TaN/HfO2/(Si)GeSn capacitors present a low leakage current of 2 × 10(-8) A/cm(2) at -1 V and a high breakdown field of ∼8 MV/cm. For large Sn content SiGeSn/GeSn direct band gap heterostructures, process temperatures below 350 °C are required for integration. We developed an atomic vapor deposition process for TaN metal gate on HfO2 high-k dielectric and validated it by resistivity as well as temperature and frequency dependent capacitance-voltage measurements of capacitors on SiGeSn and GeSn. The densities of interface traps are deduced to be in the low 10(12) cm(-2) eV(-1) range and do not depend on the Sn-concentration. The new processes developed here are compatible with (Si)GeSn integration in large scale applications.

  4. Scheme for generation of highly monochromatic X-rays from a baseline XFEL undulator

    CERN Document Server

    Geloni, Gianluca; Saldin, Evgeni

    2010-01-01

    One goal of XFEL facilities is the production of narrow bandwidth X-ray radiation. The self-seeding scheme was proposed to obtain a bandwidth narrower than that achievable with conventional X-ray SASE FELs. A self-seeded FEL is composed of two undulators separated by a monochromator and an electron beam bypass that must compensate for the path delay of X-rays in the monochromator. This leads to a long bypass, with a length in the order of 40-60 m, which requires modifications of the baseline undulator configuration. As an attempt to get around this obstacle, together with a study of the self-seeding scheme for the European XFEL, here we propose a novel technique based on a pulse doubler concept. Using a crystal monochromator installed within a short magnetic chicane in the baseline undulator, it is possible to decrease the bandwidth of the radiation well beyond the XFEL design down to 10^(-5). The magnetic chicane can be installed without any perturbation of the XFEL focusing structure, and does not interfere...

  5. A high fidelity Rydberg blockade entangling gate using shaped, analytic pulses

    CERN Document Server

    Theis, L S; Wilhelm, F K; Saffmann, M

    2016-01-01

    We show that the use of shaped pulses improves the fidelity of a Rydberg blockade two-qubit entangling gate by several orders of magnitude compared to previous protocols based on square pulses or optimal control pulses. Using analytical Derivative Removal by Adiabatic Gate (DRAG) pulses that reduce excitation of primary leakage states and an analytical method of finding the optimal Rydberg blockade we generate Bell states with a fidelity of $F>0.9999$ in a 300 K environment for a gate time of only $50\\;{\\rm ns}$, which is an order of magnitude faster than previous protocols. These results establish the potential of neutral atom qubits with Rydberg blockade gates for scalable quantum computation.

  6. Early infantile epileptic encephalopathy associated with a high voltage gated calcium channelopathy.

    Science.gov (United States)

    Edvardson, Simon; Oz, Shimrit; Abulhijaa, Fida Aziz; Taher, Flora Barghouthi; Shaag, Avraham; Zenvirt, Shamir; Dascal, Nathan; Elpeleg, Orly

    2013-02-01

    Early infantile epileptic encephalopathies usually manifest as severely impaired cognitive and motor development and often result in a devastating permanent global developmental delay and intellectual disability. A large set of genes has been implicated in the aetiology of this heterogeneous group of disorders. Among these, the ion channelopathies play a prominent role. In this study, we investigated the genetic cause of infantile epilepsy in three affected siblings. Homozygosity mapping in DNA samples followed by exome analysis in one of the patients resulted in the identification of a homozygous mutation, p.L1040P, in the CACNA2D2 gene. This gene encodes the auxiliary α(2)δ2 subunit of high voltage gated calcium channels. The expression of the α(2)δ2-L1040P mutant instead of α(2)δ2 wild-type (WT) in Xenopus laevis oocytes was associated with a notable reduction of current density of both N (Ca(V)2.2) and L (Ca(V)1.2) type calcium channels. Western blot and confocal imaging analyses showed that the α(2)δ2-L1040P mutant was synthesised normally in oocyte but only the α(2)δ2-WT, and not the α(2)δ2-L1040P mutant, increased the expression of α(1B), the pore forming subunit of Ca(V)2.2, at the plasma membrane. The expression of α(2)δ2-WT with Ca(V)2.2 increased the surface expression of α(1B) 2.5-3 fold and accelerated current inactivation, whereas α(2)δ2-L1040P did not produce any of these effects. L1040P mutation in the CACNA2D2 gene is associated with dysfunction of α(2)δ2, resulting in reduced current density and slow inactivation in neuronal calcium channels. The prolonged calcium entry during depolarisation and changes in surface density of calcium channels caused by deficient α(2)δ2 could underlie the epileptic phenotype. This is the first report of an encephalopathy caused by mutation in the auxiliary α(2)δ subunit of high voltage gated calcium channels in humans, illustrating the importance of this subunit in normal physiology of the

  7. High Fill-Factor Imagers for Neuromorphic Processing Enabled by Floating-Gate Circuits

    Directory of Open Access Journals (Sweden)

    Hasler Paul

    2003-01-01

    Full Text Available In neuromorphic modeling of the retina, it would be very nice to have processing capabilities at the focal plane while retaining the density of typical active pixel sensor (APS imager designs. Unfortunately, these two goals have been mostly incompatible. We introduce our transform imager technology and basic architecture that uses analog floating-gate devices to make it possible to have computational imagers with high pixel densities. This imager approach allows programmable focal-plane processing that can perform retinal and higher-level bioinspired computation. The processing is performed continuously on the image via programmable matrix operations that can operate on the entire image or blocks within the image. The resulting dataflow architecture can directly perform computation of spatial transforms, motion computations, and stereo computations. The core imager performs computations at the pixel plane, but still holds a fill factor greater than 40 percent—comparable to the high fill factors of APS imagers. Each pixel is composed of a photodiode sensor element and a multiplier. We present experimental results from several imager arrays built in 0.5 m process (up to in an area of 4 millimeter squared.

  8. Development of Gated Pinned Avalanche Photodiode Pixels for High-Speed Low-Light Imaging

    Directory of Open Access Journals (Sweden)

    Tomislav Resetar

    2016-08-01

    Full Text Available This work explores the benefits of linear-mode avalanche photodiodes (APDs in high-speed CMOS imaging as compared to different approaches present in literature. Analysis of APDs biased below their breakdown voltage employed in single-photon counting mode is also discussed, showing a potentially interesting alternative to existing Geiger-mode APDs. An overview of the recently presented gated pinned avalanche photodiode pixel concept is provided, as well as the first experimental results on a 8 × 16 pixel test array. Full feasibility of the proposed pixel concept is not demonstrated; however, informative data is obtained from the sensor operating under −32 V substrate bias and clearly exhibiting wavelength-dependent gain in frontside illumination. The readout of the chip designed in standard 130 nm CMOS technology shows no dependence on the high-voltage bias. Readout noise level of 15 e - rms, full well capacity of 8000 e - , and the conversion gain of 75 µV / e - are extracted from the photon-transfer measurements. The gain characteristics of the avalanche junction are characterized on separate test diodes showing a multiplication factor of 1.6 for red light in frontside illumination.

  9. Development of Gated Pinned Avalanche Photodiode Pixels for High-Speed Low-Light Imaging.

    Science.gov (United States)

    Resetar, Tomislav; De Munck, Koen; Haspeslagh, Luc; Rosmeulen, Maarten; Süss, Andreas; Puers, Robert; Van Hoof, Chris

    2016-08-15

    This work explores the benefits of linear-mode avalanche photodiodes (APDs) in high-speed CMOS imaging as compared to different approaches present in literature. Analysis of APDs biased below their breakdown voltage employed in single-photon counting mode is also discussed, showing a potentially interesting alternative to existing Geiger-mode APDs. An overview of the recently presented gated pinned avalanche photodiode pixel concept is provided, as well as the first experimental results on a 8 × 16 pixel test array. Full feasibility of the proposed pixel concept is not demonstrated; however, informative data is obtained from the sensor operating under -32 V substrate bias and clearly exhibiting wavelength-dependent gain in frontside illumination. The readout of the chip designed in standard 130 nm CMOS technology shows no dependence on the high-voltage bias. Readout noise level of 15 e - rms, full well capacity of 8000 e - , and the conversion gain of 75 µV / e - are extracted from the photon-transfer measurements. The gain characteristics of the avalanche junction are characterized on separate test diodes showing a multiplication factor of 1.6 for red light in frontside illumination.

  10. MOS Ge Diodes Based on High κ Gate Dielectrics Grown by MBE and ALD

    Science.gov (United States)

    Lee, Kun Yu; Lee, W. C.; Lin, T. D.; Lee, C. S.; Chang, Y. C.; Lee, Y. J.; Huang, M. L.; Wu, Y. D.; Hong, M.; Kwo, J.

    2007-03-01

    Germanium-based CMOS technology is gaining importance due to its high carrier mobility. In this work high κ gate-dielectrics, Al2O3, HfO2, Y2O3 and Ga2O3(Gd2O3) grown by MBE and ALD were investigated as passivation layers on n type Ge(100). Thermal stability of the MOS diodes was examined after various anneals. Prior to dielectric depositions surface pretreatments were applied to reduce the unwanted GeOx interfacial layer, and to improve electrical properties. Frequency dispersion of C-V curves was reduced by using a 350^oC preclean process, compared to the sample without precleaning. The leakage current density of ALD grown HfO2 (6.8nm) is 4.6×10-6 A/cm^2 with κ of 10.5. The improved CV curve was attributed to less GeOx formed at substrate and oxide interface, as confirmed by XPS analysis. However, with higher cleaning temperature over 400^oC, the CV curves showed additional inversion capacitance, possibly due to minority carriers from defect states near the interface.

  11. Detecting Subsidence Along a High Speed Railway by Ultrashort Baseline TCP-InSAR with High Resolution Images

    Science.gov (United States)

    Dai, K. R.; Liu, G. X.; Yu, B.; Jia, H. G.; Ma, D. Y.; Wang, X. W.

    2013-10-01

    A High Speed Railway goes across Wuqing district of Tianjin, China. Historical studies showed that the land subsidence of this area was very serious, which would give rise to huge security risk to the high speed railway. For detecting the detailed subsidence related to the high speed railway, we use the multi-temporal InSAR (MT-InSAR) technique to extract regional scale subsidence of Wuqing district. Take it into consideration that Wuqing district is a suburban region with large area of low coherence farmland, we select the temporarily coherent point InSAR (TCP-InSAR) approach for MT-InSAR analysis. The TCP-InSAR is a potential approach for detecting land subsidence in low coherence areas as it can identify and analysis coherent points between just two images and can acquire a reliable solution without conventional phase unwrapping. This paper extended the TCP-InSAR with use of ultrashort spatial baseline (USB) interferograms. As thetopographic effects are negligible in the USB interferograms, an external digital elevation model (DEM) is no longer needed in interferometric processing, and the parameters needed to be estimated were simplified at the same time. With use of 17 TerraSAR-X (TSX) images acquired from 2009 to 2010 over Wuqing district, the annual subsidence rates along the high speed railway were derived by the USB-TCPInSAR approach. Two subsidence funnels were found at ShuangJie town and around Wuqing Station with subsidence rate of -17 ∼ -27 mm/year and -7 ∼ -17 mm/year, respectively. The subsidence rates derived by USB-TCPInSAR were compared with those derived by the conventional TCP-InSAR that uses an external DEM for differential interferometry. The mean and the standard deviation of the differences between two types of results at 370697 TCPs are -4.43 × 10-6 mm/year and ±1.4673 mm/year, respectively. Further comparison with the subsidence results mentioned in several other studies were made, which shows good consistencies. The results verify

  12. High-Temperature SiC Power Module with Integrated SiC Gate Drivers for Future High-Density Power Electronics Applications

    Energy Technology Data Exchange (ETDEWEB)

    Whitaker, Mr. Bret [APEI, Inc.; Cole, Mr. Zach [APEI, Inc.; Passmore, Mr. Brandon [APEI, Inc.; Mcnutt, Tyler [APEI, Inc.; Lostetter, Dr. Alex [APEI, Inc.; Ericson, Milton Nance [ORNL; Frank, Steven [ORNL; Britton Jr, Charles L [ORNL; Marlino, Laura D [ORNL; Mantooth, Alan [University of Arkansas; Francis, Matt [APEI, Inc.; Lamichhane, Ranjan [APEI, Inc.; Shepherd, Paul [APEI, Inc.; Glover, Michael [APEI, Inc.

    2014-01-01

    This paper presents a high-temperature capable intelligent power module that contains SiC power devices and SiC gate driver integrated circuits (ICs). The high-temperature capability of the SiC gate driver ICs allows for them to be packaged into the power module and be located physically close to the power devices. This provides a distinct advantage by reducing the gate driver loop inductance, which promotes high frequency operation, while also reducing the overall volume of the system through higher levels of integration. The power module was tested in a bridgeless-boost converter (Fig. 1) to determine the performance of the module in a system level application. The converter was operated with a switching frequency of 200 kHz with a peak output power of approximately 5 kW. The peak efficiency was found to be 97.5% at 2.9 kW.

  13. High Mobility and Low Density of Trap States in Dual-Solid-Gated PbS Nanocrystal Field-Effect Transistors

    NARCIS (Netherlands)

    Nugraha, Mohamad Insan; Haeusermann, Roger; Bisri, Satria Zulkarnaen; Matsui, Hiroyuki; Sytnyk, Mykhailo; Heiss, Wolfgang; Takeya, Jun; Loi, Maria Antonietta

    2015-01-01

    Dual-gated PbS nanocrystal field-effect transistors employing SiO2 and Cytop as gate dielectrics are fabricated. The obtained electron mobility (0.2 cm(2) V-1 s(-1)) and the high on/off ratio (10(5)-10(6)), show that the controlled nanocrystal assembly (obtained with self-assembled monolayers), as w

  14. Electrical characterization of thulium silicate interfacial layers for integration in high-k/metal gate CMOS technology

    Science.gov (United States)

    Dentoni Litta, Eugenio; Hellström, Per-Erik; Henkel, Christoph; Östling, Mikael

    2014-08-01

    This work presents a characterization of the electrical properties of thulium silicate thin films, within the scope of a possible application as IL (interfacial layer) in scaled high-k/metal gate CMOS technology. Silicate formation is investigated over a wide temperature range (500-900 °C) through integration in MOS capacitor structures and analysis of the resulting electrical properties. The results are compared to those obtained from equivalent devices integrating lanthanum silicate interfacial layers. The thulium silicate IL is formed through a gate-last CMOS-compatible process flow, providing IL EOT of 0.1-0.3 nm at low formation temperature and interface state density at flatband condition below 2 × 1011 cm-2 eV-1. The effects of a possible integration in a gate-first process flow with a maximum thermal budget of 1000 °C are also evaluated, achieving an IL EOT of 0.2-0.5 nm, an interface state density at flatband condition ∼1 × 1011 cm-2 eV-1 and a reduction in gate leakage current density of one order of magnitude compared to the same stack without IL.

  15. A physics-based potential and electric field model of a nanoscale rectangular high-K gate dielectric HEMT

    Indian Academy of Sciences (India)

    Das B; Goswami R; Bhowmick B

    2016-04-01

    In this paper, we have developed a physics-based model for surface potential, channel potential, electric field and drain current for AlGaN/GaN high electron mobility transistor with high-K gate dielectric using two-dimensional Poisson equation under full depletion approximation with the inclusion of effect of polarization charges. The accuracy of the model has been verified and is found to be in good agreement with the simulated results.

  16. Carrier-wave steepened pulses and gradient-gated high-order harmonic generation

    CERN Document Server

    Radnor, S B P; Kinsler, P; New, G H C

    2008-01-01

    We show how to optimize the process of high-harmonic generation (HHG) by gating the interaction using the field gradient of the driving pulse. Since maximized field gradients are efficiently generated by self-steepening processes, we first present a generalized theory of optical carrier-wave self-steepened (CSS) pulses. This goes beyond existing treatments, which only consider third-order nonlinearity, and has the advantage of describing pulses whose wave forms have a range of symmetry properties. Although a fertile field for theoretical work, CSS pulses are difficult to realize experimentally because of the deleterious effect of dispersion. We therefore consider synthesizing CSS-like profiles using a suitably phased sub-set of the harmonics present in a true CSS wave form. Using standard theoretical models of HHG, we show that the presence of gradient-maximized regions on the wave forms can raise the spectral cut-off and so yield shorter attosecond pulses. We study how the quality of the attosecond bursts cr...

  17. HiGate (High Grade Anti-Tamper Equipment Prototype and Application to e-Discovery

    Directory of Open Access Journals (Sweden)

    Yui Sakurai

    2010-06-01

    Full Text Available These days, most data is digitized and processed in various ways by computers. In the past, computer owners were free to process data as desired and to observe the inputted data as well as the interim results. However, the unrestricted processing of data and accessing of interim results even by computer users is associated with an increasing number of adverse events. These adverse events often occur when sensitive data such as personal or confidential business information must be handled by two or more parties, such as in the case of e-Discovery, used in legal proceedings, or epidemiologic studies. To solve this problem, providers encrypt data, and the owner of the computer performs decoding in the memory for encrypted data. The computer owner can be limited to performing only certain processing of data and to observing only the final results. As an implementation that uses existing technology to realize this solution, the processing of data contained in a smart card was considered, but such an implementation would not be practical due to issues related to computer capacity and processing speed. Accordingly, the authors present the concept of PC-based High Grade Anti-Tamper Equipment (HiGATE, which allows data to be handled without revealing the data content to administrators or users. To verify this concept, an e-Discovery application on a prototype was executed and the results are reported here.

  18. Baseline rationing

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Moreno-Ternero, Juan D.; Østerdal, Lars Peter Raahave

    The standard problem of adjudicating conflicting claims describes a situation in which a given amount of a divisible good has to be allocated among agents who hold claims against it exceeding the available amount. This paper considers more general rationing problems in which, in addition to claims......, there exist baselines (to be interpreted as objective entitlements, ideal targets, or past consumption) that might play an important role in the allocation process. The model we present is able to accommodate real-life rationing situations, ranging from resource allocation in the public health care sector...... to international protocols for the reduction of greenhouse emissions, or water distribution in drought periods. We define a family of allocation methods for such general rationing problems - called baseline rationing rules - and provide an axiomatic characterization for it. Any baseline rationing rule within...

  19. High-Performance Flexible Organic Nano-Floating Gate Memory Devices Functionalized with Cobalt Ferrite Nanoparticles.

    Science.gov (United States)

    Jung, Ji Hyung; Kim, Sunghwan; Kim, Hyeonjung; Park, Jongnam; Oh, Joon Hak

    2015-10-07

    Nano-floating gate memory (NFGM) devices are transistor-type memory devices that use nanostructured materials as charge trap sites. They have recently attracted a great deal of attention due to their excellent performance, capability for multilevel programming, and suitability as platforms for integrated circuits. Herein, novel NFGM devices have been fabricated using semiconducting cobalt ferrite (CoFe2O4) nanoparticles (NPs) as charge trap sites and pentacene as a p-type semiconductor. Monodisperse CoFe2O4 NPs with different diameters have been synthesized by thermal decomposition and embedded in NFGM devices. The particle size effects on the memory performance have been investigated in terms of energy levels and particle-particle interactions. CoFe2O4 NP-based memory devices exhibit a large memory window (≈73.84 V), a high read current on/off ratio (read I(on)/I(off)) of ≈2.98 × 10(3), and excellent data retention. Fast switching behaviors are observed due to the exceptional charge trapping/release capability of CoFe2O4 NPs surrounded by the oleate layer, which acts as an alternative tunneling dielectric layer and simplifies the device fabrication process. Furthermore, the NFGM devices show excellent thermal stability, and flexible memory devices fabricated on plastic substrates exhibit remarkable mechanical and electrical stability. This study demonstrates a viable means of fabricating highly flexible, high-performance organic memory devices. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Mechanism Study of Gate Leakage Current for AlGaN/GaN High Electron Mobility Transistor Structure Under High Reverse Bias by Thin Surface Barrier Model and Technology Computer Aided Design Simulation

    Science.gov (United States)

    Hayashi, Kazuo; Yamaguchi, Yutaro; Oishi, Toshiyuki; Otsuka, Hiroshi; Yamanaka, Koji; Nakayama, Masatoshi; Miyamoto, Yasuyuki

    2013-04-01

    Gate leakage current mechanism in GaN high electron mobility transistors (HEMTs) has been studied using a two-dimensional thin surface barrier (TSB) model to represent two unintentional donor thin layers that exit under and outside the gate electrode due to the existence of surface defects. The donor thin layer outside the gate affects the reverse gate current at the high gate voltage above the pinch-off voltage. Higher donor concentration of thin layer outside the gate results in larger ratio of lateral to vertical components of the electric field at the gate edge. On the other hand, the electric field at the center of the gate has only the vertical electric field component. As a result, the two-dimensional effects are only important for the reverse gate current above the pinch-off voltage. We have confirmed in this paper that the simulation results provided by our model correlate very well with the experimental reverse gate current characteristics of the device for a very wide range of reverse gate voltage from 0.1 to 90 V.

  1. Electrical and Structural Characteristics of High-k Gate Dielectrics with Epitaxial Si3N4 Interfacial Layer on Si(111)

    Science.gov (United States)

    Sim, Hyunjun; Samantaray, Chandan B.; Lee, Taeho; Yeom, Hanwoong; Hwang, Hyunsang

    2004-12-01

    In this study, the electrical and structural characteristics of Gd2O3 gate dielectrics with an epitaxial Si3N4 interfacial layer grown on Si(111) were investigated. Compared with control Gd2O3 gate dielectrics deposited on HF-last treated Si (111), the Gd2O3 gate dielectrics with an epitaxial Si3N4 interfacial layer exhibited excellent electrical characteristics such as low leakage current density and low interface state density. These characteristics are due to a high-quality interfacial layer formation on Si. Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy were employed to analyze the structures of the gate dielectrics and interfacial layer. High-k gate dielectrics with an epitaxial Si3N4 interfacial layer have considerable potential for future use in sub-0.1 μm metal oxide semiconductor field-effect transistors (MOSFETs).

  2. Fabrication and characteristics of ZnO MOS capacitors with high-K HfO2 gate dielectrics

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    ZnO thin films are first deposited on n-type silicon by radio frequency (rf) magnetron sputtering at room temperature.And high-K HfO2 gate dielectrics thin films are deposited on ZnO films to form metal-oxide semiconductor (MOS) capacitors.The temperature to fabricate ZnO MOS capacitors is 400°C,and the low temperature process is applicable for thin film transistors,flat-panel display (FPD),flexible display,etc.The electronic availability of ZnO thin films,which serve as a semiconductor material for MOS capacitors with HfO2 gate dielectric is investigated.High frequency (1 MHz) capacitance-voltage (C-V) and current-voltage (I-V) characteristics of ZnO-based MOS capacitors are measured.The thermal stability and electronic stability of the ZnO capacitors are investigated,respectively.Experimental results indicate that good electrical characteristics can be obtained on ZnO substrates with high-K HfO2 gate dielectrics.Besides,the ZnO capacitors can exhibit high thermal and electronic stabilities.

  3. High-dimensional Controlled-phase Gate Between a 2 N -dimensional Photon and N Three-level Artificial Atoms

    Science.gov (United States)

    Ma, Yun-Ming; Wang, Tie-Jun

    2017-10-01

    Higher-dimensional quantum system is of great interest owing to the outstanding features exhibited in the implementation of novel fundamental tests of nature and application in various quantum information tasks. High-dimensional quantum logic gate is a key element in scalable quantum computation and quantum communication. In this paper, we propose a scheme to implement a controlled-phase gate between a 2 N -dimensional photon and N three-level artificial atoms. This high-dimensional controlled-phase gate can serve as crucial components of the high-capacity, long-distance quantum communication. We use the high-dimensional Bell state analysis as an example to show the application of this device. Estimates on the system requirements indicate that our protocol is realizable with existing or near-further technologies. This scheme is ideally suited to solid-state integrated optical approaches to quantum information processing, and it can be applied to various system, such as superconducting qubits coupled to a resonator or nitrogen-vacancy centers coupled to a photonic-band-gap structures.

  4. Implementation of nanoscale circuits using dual metal gate engineered nanowire MOSFET with high-k dielectrics for low power applications

    Science.gov (United States)

    Charles Pravin, J.; Nirmal, D.; Prajoon, P.; Ajayan, J.

    2016-09-01

    This work covers the impact of dual metal gate engineered Junctionless MOSFET with various high-k dielectric in Nanoscale circuits for low power applications. Due to gate engineering in junctionless MOSFET, graded potential is obtained and results in higher electron velocity of about 31% for HfO2 than SiO2 in the channel region, which in turn improves the carrier transport efficiency. The simulation is done using sentaurus TCAD, ON current, OFF current, ION/IOFF ratio, DIBL, gain, transconductance and transconductance generation factor parameters are analysed. When using HfO2, DIBL shows a reduction of 61.5% over SiO2. The transconductance and transconductance generation factor shows an improvement of 44% and 35% respectively. The gain and output resistance also shows considerable improvement with high-k dielectrics. Using this device, inverter circuit is implemented with different high-k dielectric material and delay have been decreased by 4% with HfO2 when compared to SiO2. In addition, a significant reduction in power dissipation of the inverter circuit is obtained with high-k dielectric Dual Metal Surround Gate Junctionless Transistor than SiO2 based device. From the analysis, it is found that HfO2 will be a better alternative for the future nanoscale device.

  5. Effective Work Function Engineering for Aggressively Scaled Planar and Multi-Gate Fin Field-Effect Transistor-Based Devices with High-k Last Replacement Metal Gate Technology

    Science.gov (United States)

    Veloso, Anabela; Aik Chew, Soon; Higuchi, Yuichi; Ragnarsson, Lars-Åke; Simoen, Eddy; Schram, Tom; Witters, Thomas; Van Ammel, Annemie; Dekkers, Harold; Tielens, Hilde; Devriendt, Katia; Heylen, Nancy; Sebaai, Farid; Brus, Stephan; Favia, Paola; Geypen, Jef; Bender, Hugo; Phatak, Anup; Chen, Michael S.; Lu, Xinliang; Ganguli, Seshadri; Lei, Yu; Tang, Wei; Fu, Xinyu; Gandikota, Srinivas; Noori, Atif; Brand, Adam; Yoshida, Naomi; Thean, Aaron; Horiguchi, Naoto

    2013-04-01

    This work reports on aggressively scaled replacement metal gate, high-k last devices (RMG-HKL), exploring several options for effective work function (EWF) engineering, and targeting logic high-performance and low-power applications. Tight low-threshold voltage (VT) distributions for scaled NMOS devices are obtained by controlled TiN/TiAl-alloying, either by using RF-physical vapor deposition (RF-PVD) or atomic layer deposition (ALD) for TiN growth. The first technique allows optimization of the TiAl/TiN thicknesses at the bottom of gate trenches while maximizing the space to be filled with a low-resistance metal; using ALD minimizes the occurrence of preferential paths, at gate sidewalls, for Al diffusion into the high-k dielectric, reducing gate leakage (JG). For multi-gate fin field-effect transistors (FinFETs) which require smaller EWF shifts from mid-gap for low-VT: 1) conformal, lower-JG ALD-TiN/TaSiAl; and 2) Al-rich ALD-TiN by controlled Al diffusion from the fill-metal are demonstrated to be promising candidates. Comparable bias temperature instability (BTI), improved noise behavior, and slightly reduced equivalent oxide thickness (EOT) are measured on Al-rich EWF-metal stacks.

  6. Electrical transport properties of ReS2 with polymer electrolyte gating in the high-doping limit

    Science.gov (United States)

    Ovchinnikov, Dmitry; Allain, Adrien; Pasquier, Diego; Dumcenco, Dumitru; Ho, Ching-Hwa; Huang, Ying-Sheng; Yazyev, Oleg; Kis, Andras

    Two-dimensional (2D) materials have emerged as promising candidates for future electronic applications. Among them, transition metal dichalcogenides (TMDs) demonstrate not only potential as ultrathin transistor channel material, but also intriguing spin and valley physics, which in principle could allow new types of devices and circuits. Here we report on the first study of two-dimensional anisotropic ReS2 at high doping levels, enabled by polymer electrolyte gating. Significantly increasing the doping level using electrolyte instead of standard solid gate, we measured an unusual modulation of the conductivity at high carrier densities in monolayer ReS2. In the case of thicker flakes, the effect is milder and an insulator-metal-insulator sequence with increasing doping is observed. Transport measurements provide the evidence of major influence of ionic disorder. Furthermore, we discuss possible band structure effects.

  7. Silicon-on-insulator-based high-voltage, high-temperature integrated circuit gate driver for silicon carbide-based power field effect transistors

    Energy Technology Data Exchange (ETDEWEB)

    Tolbert, Leon M [ORNL; Huque, Mohammad A [ORNL; Blalock, Benjamin J [ORNL; Islam, Syed K [ORNL

    2010-01-01

    Silicon carbide (SiC)-based field effect transistors (FETs) are gaining popularity as switching elements in power electronic circuits designed for high-temperature environments like hybrid electric vehicle, aircraft, well logging, geothermal power generation etc. Like any other power switches, SiC-based power devices also need gate driver circuits to interface them with the logic units. The placement of the gate driver circuit next to the power switch is optimal for minimising system complexity. Successful operation of the gate driver circuit in a harsh environment, especially with minimal or no heat sink and without liquid cooling, can increase the power-to-volume ratio as well as the power-to-weight ratio for power conversion modules such as a DC-DC converter, inverter etc. A silicon-on-insulator (SOI)-based high-voltage, high-temperature integrated circuit (IC) gate driver for SiC power FETs has been designed and fabricated using a commercially available 0.8--m, 2-poly and 3-metal bipolar-complementary metal oxide semiconductor (CMOS)-double diffused metal oxide semiconductor (DMOS) process. The prototype circuit-s maximum gate drive supply can be 40-V with peak 2.3-A sourcing/sinking current driving capability. Owing to the wide driving range, this gate driver IC can be used to drive a wide variety of SiC FET switches (both normally OFF metal oxide semiconductor field effect transistor (MOSFET) and normally ON junction field effect transistor (JFET)). The switching frequency is 20-kHz and the duty cycle can be varied from 0 to 100-. The circuit has been successfully tested with SiC power MOSFETs and JFETs without any heat sink and cooling mechanism. During these tests, SiC switches were kept at room temperature and ambient temperature of the driver circuit was increased to 200-C. The circuit underwent numerous temperature cycles with negligible performance degradation.

  8. Mismatch of dielectric constants at the interface of nanometer metal-oxide-semiconductor devices with high- gate dielectric impacts on the inversion charge density

    Indian Academy of Sciences (India)

    Ling-Feng Mao

    2011-04-01

    The comparison of the inversion electron density between a nanometer metal-oxidesemiconductor (MOS) device with high- gate dielectric and a SiO2 MOS device with the same equivalent oxide thickness has been discussed. A fully self-consistent solution of the coupled Schrödinger–Poisson equations demonstrates that a larger dielectric-constant mismatch between the gate dielectric and silicon substrate can reduce electron density in the channel of a MOS device under inversion bias. Such a reduction in inversion electron density of the channel will increase with increase in gate voltage. A reduction in the charge density implies a reduction in the inversion electron density in the channel of a MOS device. It also implies that a larger dielectric constant of the gate dielectric might result in a reduction in the source–drain current and the gate leakage current.

  9. Formation of combined partially recessed and multiple fluorinated-dielectric layers gate structures for high threshold voltage GaN-based HEMT power devices

    Science.gov (United States)

    Huang, Huolin; Liang, Yung Chii

    2015-12-01

    The formation of partial AlGaN trench recess filled with multiple fluorinated gate dielectric layers as metal-insulator-semiconductor (MIS) gate structure for GaN-based HEMT power devices is designed, fabricated and experimentally verified. The approach realizes the device normally-off operational mode and at the same time is able to preserve the good mobility in the 2DEG channel for a maximum on-state current. Experimental measurements on the fabricated MIS-HEMT devices indicate a high gate threshold voltage (Vth) at around 5 V and a very low gate leakage current at pA/mm level. This proposed gate structure provides very promising properties for GaN-based power semiconductor devices in future power electronics switching applications.

  10. NOT and NAND logic circuits composed of top-gate ZnO nanowire field-effect transistors with high-k Al(2)O(3) gate layers.

    Science.gov (United States)

    Yeom, Donghyuk; Keem, Kihyun; Kang, Jeongmin; Jeong, Dong-Young; Yoon, Changjoon; Kim, Dongseung; Kim, Sangsig

    2008-07-02

    Electrical characteristics of NOT and NAND logic circuits fabricated using top-gate ZnO nanowire field-effect transistors (FETs) with high-k Al(2)O(3) gate layers were investigated in this study. To form a NOT logic circuit, two identical FETs whose I(on)/I(off) ratios were as high as ∼10(8) were connected in series in a single ZnO nanowire channel, sharing a common source electrode. Its voltage transfer characteristics exhibited an inverting operation and its logic swing was 98%. In addition, the characteristics of a NAND logic circuit composed of three top-gate FETs connected in series in a single nanowire channel are discussed in this paper.

  11. Highly stable carbon nanotube top-gate transistors with tunable threshold voltage

    NARCIS (Netherlands)

    Wang, H.; Cobb, B.; Breemen, A. van; Gelinck, G.H.; Bao, Z.

    2014-01-01

    Carbon-nanotube top-gate transistors with fluorinated dielectrics are presented. With PTrFE as the dielectric, the devices have absent or small hysteresis at different sweep rates and excellent bias-stress stability under ambient conditions. Ambipolar single-walled carbon nanotube (SWNT) transistors

  12. High carrier mobility of CoPc wires based field-effect transistors using bi-layer gate dielectric

    Directory of Open Access Journals (Sweden)

    Murali Gedda

    2013-11-01

    Full Text Available Polyvinyl alcohol (PVA and anodized Al2O3 layers were used as bi-layer gate for the fabrication of cobalt phthalocyanine (CoPc wire base field-effect transistors (OFETs. CoPc wires were grown on SiO2 surfaces by organic vapor phase deposition method. These devices exhibit a field-effect carrier mobility (μEF value of 1.11 cm2/Vs. The high carrier mobility for CoPc molecules is attributed to the better capacitive coupling between the channel of CoPc wires and the gate through organic-inorganic dielectric layer. Our measurements also demonstrated the way to determine the thicknesses of the dielectric layers for a better process condition of OFETs.

  13. Baseline correlates of insulin resistance in inner city high-BMI African-American children.

    Science.gov (United States)

    Raman, Aarthi; Fitch, Mark D; Hudes, Mark L; Lustig, Robert H; Murray, Carolyn B; Ikeda, Joanne P; Fleming, Sharon E

    2008-09-01

    To characterize the influence of diet-, physical activity-, and self-esteem-related factors on insulin resistance in 8- 10-year-old African-American (AA) children with BMI greater than the 85th percentile who were screened to participate in a community-based type 2 diabetes mellitus (T2DM) prevention trial. In 165 subjects, fasting glucose- and insulin-derived values for homeostasis model assessment of insulin resistance (HOMA-IR) assessed insulin resistance. Body fatness was calculated following bioelectrical impedance analysis, and fitness was measured using laps from a 20-m shuttle run. Child questionnaires assessed physical activity, dietary habits, and self-esteem. Pubertal staging was assessed using serum levels of sex hormones. Parent questionnaires assessed family demographics, family health, and family food and physical activity habits. Girls had significantly higher percent body fat but similar anthropometric measures compared with boys, whereas boys spent more time in high-intensity activities than girls. Scores for self-perceived behavior were higher for girls than for boys; and girls desired a more slender body. Girls had significantly higher insulin resistance (HOMA-IR), compared with boys (P < 0.01). Adjusting for age, sex, pubertal stage, socioeconomic index (SE index), and family history of diabetes, multivariate regression analysis showed that children with higher waist circumference (WC) (P < 0.001) and lower Harter's scholastic competence (SC) scale (P = 0.044) had higher insulin resistance. WC and selected self-esteem parameters predicted insulin resistance in high-BMI AA children. The risk of T2DM may be reduced in these children by targeting these factors.

  14. Two methods of tuning threshold voltage of bulk FinFETs with replacement high-k metal-gate stacks

    Science.gov (United States)

    Xu, Miao; Zhu, Huilong; Zhang, Yanbo; Xu, Qiuxia; Zhang, Yongkui; Qin, Changliang; Zhang, Qingzhu; Yin, Huaxiang; Xu, Hao; Chen, Shuai; Luo, Jun; Li, Chunlong; Zhao, Chao; Ye, Tianchun

    2017-03-01

    In this work, we propose two threshold voltage (VTH) tuning methods for bulk FinFETs with replacement high-k metal gate. The first method is to perform a vertical implantation into fin structure after dummy gate removal, self-aligned forming halo & punch through stop pocket (halo & PTSP) doping profile. The second method is to execute P+/BF2+ ion implantations into the single common work function (WF) layer in N-/P-FinFETs, respectively. These two methods have been investigated by TCAD simulations and MOS-capacitor experiments respectively, and then integrated into FinFET fabrication successfully. Experimental results show that the halo & PTSP doping profile can reduce VTH roll off and total variation. With P+/BF2+ doped WF layer, the VTH-sat shift -0.43 V/+1.26 V for N-FinFETs and -0.75 V/+0.11 V for P-FinFETs, respectively, with gate length of 500 nm. The proposed two methods are simple and effective for FinFET VTH tuning, and have potential for future application of massive production.

  15. Effect of gate length on breakdown voltage in AlGaN/GaN high-electron-mobility transistor

    Science.gov (United States)

    Jun, Luo; Sheng-Lei, Zhao; Min-Han, Mi; Wei-Wei, Chen; Bin, Hou; Jin-Cheng, Zhang; Xiao-Hua, Ma; Yue, Hao

    2016-02-01

    The effects of gate length LG on breakdown voltage VBR are investigated in AlGaN/GaN high-electron-mobility transistors (HEMTs) with LG = 1 μm˜ 20 μm. With the increase of LG, VBR is first increased, and then saturated at LG = 3 μm. For the HEMT with LG = 1 μm, breakdown voltage VBR is 117 V, and it can be enhanced to 148 V for the HEMT with LG = 3 μm. The gate length of 3 μm can alleviate the buffer-leakage-induced impact ionization compared with the gate length of 1 μm, and the suppression of the impact ionization is the reason for improving the breakdown voltage. A similar suppression of the impact ionization exists in the HEMTs with LG > 3 μm. As a result, there is no obvious difference in breakdown voltage among the HEMTs with LG = 3 μm˜20 μm, and their breakdown voltages are in a range of 140 V-156 V. Project supported by the National Natural Science Foundation of China (Grant Nos. 61334002, 61106106, and 61204085).

  16. Investigation of gate-diode degradation in normally-off p-GaN/AlGaN/GaN high-electron-mobility transistors

    Science.gov (United States)

    Tapajna, M.; Hilt, O.; Bahat-Treidel, E.; Würfl, J.; Kuzmík, J.

    2015-11-01

    Gate diode conduction mechanisms were analyzed in normally-off p-GaN/AlGaN/GaN high-electron mobility transistors grown on Si wafers before and after forward bias stresses. Electrical characterization of the gate diodes indicates forward current to be limited by channel electrons injected through the AlGaN/p-GaN triangular barrier promoted by traps. On the other hand, reverse current was found to be consistent with carrier generation-recombination processes in the AlGaN layer. Soft breakdown observed after ˜105 s during forward bias stress at gate voltage of 7 V was attributed to formation of conductive channel in p-GaN/AlGaN gate stack via trap generation and percolation mechanism, likely due to coexistence of high electric field and high forward current density. Possible enhancement of localized conductive channels originating from spatial inhomogeneities is proposed to be responsible for the degradation.

  17. Understanding the Structure of High-K Gate Oxides - Oral Presentation

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, Andre [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-08-25

    Hafnium Oxide (HfO2) amorphous thin films are being used as gate oxides in transistors because of their high dielectric constant (κ) over Silicon Dioxide. The present study looks to find the atomic structure of HfO2 thin films which hasn’t been done with the technique of this study. In this study, two HfO2 samples were studied. One sample was made with thermal atomic layer deposition (ALD) on top of a Chromium and Gold layer on a silicon wafer. The second sample was made with plasma ALD on top of a Chromium and Gold layer on a Silicon wafer. Both films were deposited at a thickness of 50nm. To obtain atomic structure information, Grazing Incidence X-ray diffraction (GIXRD) was carried out on the HfO2 samples. Because of this, absorption, footprint, polarization, and dead time corrections were applied to the scattering intensity data collected. The scattering curves displayed a difference in structure between the ALD processes. The plasma ALD sample showed the broad peak characteristic of an amorphous structure whereas the thermal ALD sample showed an amorphous structure with characteristics of crystalline materials. This appears to suggest that the thermal process results in a mostly amorphous material with crystallites within. Further, the scattering intensity data was used to calculate a pair distribution function (PDF) to show more atomic structure. The PDF showed atom distances in the plasma ALD sample had structure up to 10 Å, while the thermal ALD sample showed the same structure below 10 Å. This structure that shows up below 10 Å matches the bond distances of HfO2 published in literature. The PDF for the thermal ALD sample also showed peaks up to 20 Å, suggesting repeating atomic spacing outside the HfO2 molecule in the sample. This appears to suggest that there is some crystalline structure within the thermal ALD sample.

  18. A Bioinspired Multifunctional Heterogeneous Membrane with Ultrahigh Ionic Rectification and Highly Efficient Selective Ionic Gating.

    Science.gov (United States)

    Zhang, Zhen; Kong, Xiang-Yu; Xiao, Kai; Xie, Ganhua; Liu, Qian; Tian, Ye; Zhang, Huacheng; Ma, Jie; Wen, Liping; Jiang, Lei

    2016-01-06

    A bioinspired multifunctional heterogeneous membrane composed of a block copolymer (PS-b-P4VP) membrane and a porous anodic alumina membrane is fabricated. The ionic rectification is so strong that the maximum ratio is ≈489, and the chemical actuation of the anion or cation gate from the "OFF" to the "ON" state promotes a 98.5% increase in the channel conductance.

  19. High-speed all-optical NAND/AND logic gates using four-wave mixing Bragg scattering.

    Science.gov (United States)

    Li, Kangmei; Ting, Hong-Fu; Foster, Mark A; Foster, Amy C

    2016-07-15

    A high-speed all-optical NAND logic gate is proposed and experimentally demonstrated using four-wave mixing Bragg scattering in highly nonlinear fiber. NAND/AND logic functions are implemented at two wavelengths by encoding logic inputs on two pumps via on-off keying. A 15.2-dB depletion of the signal is obtained for NAND operation, and time domain measurements show 10-Gb/s NAND/AND logic operations with open eye diagrams. The approach can be readily extended to higher data rates and transferred to on-chip waveguide platforms.

  20. Repetition-rate-selectable high-speed optical gating in a VO{sub 2} thin film based on gain modulation of optical amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Wook; Kim, Bong Jun; Choi, Sung Youl; Chae, Byung Gyu; Kim, Hyun Tak [Electronics and Telecommunications Research Institute, Daejeon (Korea, Republic of); Lee, Yong Wook [Pukyong National University, Busan (Korea, Republic of); Seo, Gi Wan [University of Science and Technology, Daejeon (Korea, Republic of); Lee, Yong Wan [University of Minnesota, Minneapolis, MN (United States)

    2010-12-15

    In this research, we investigated the dependence of the saturation-induced gain modulation (SIGM) on the modulation frequency of the input signal in an erbium-doped fiber amplifier (EDFA). By finding and incorporating the modulation frequency invariance of the SIGM realizable within some frequency range, we demonstrated a repetition-rate-selectable high-speed optical gating in two-terminal electrical devices based on vanadium-dioxide thin films. In the implemented optical gating system, the repetition rate could be freely chosen as an arbitrary frequency between 0.27 and 10 kHz without any degradation of the gating speed and the signal-to-noise ratio.

  1. Lowering the environmental impact of high-kappa/ metal gate stack surface preparation processes

    Science.gov (United States)

    Zamani, Davoud

    ABSTRACT Hafnium based oxides and silicates are promising high-κ dielectrics to replace SiO2 as gate material for state-of-the-art semiconductor devices. However, integrating these new high-κ materials into the existing complementary metal-oxide semiconductor (CMOS) process remains a challenge. One particular area of concern is the use of large amounts of HF during wet etching of hafnium based oxides and silicates. The patterning of thin films of these materials is accomplished by wet etching in HF solutions. The use of HF allows dissolution of hafnium as an anionic fluoride complex. Etch selectivity with respect to SiO2 is achieved by appropriately diluting the solutions and using slightly elevated temperatures. From an ESH point of view, it would be beneficial to develop methods which would lower the use of HF. The first objective of this study is to find new chemistries and developments of new wet etch methods to reduce fluoride consumption during wet etching of hafnium based high-κ materials. Another related issue with major environmental impact is the usage of large amounts of rinsing water for removal of HF in post-etch cleaning step. Both of these require a better understanding of the HF interaction with the high-κ surface during the etching, cleaning, and rinsing processes. During the rinse, the cleaning chemical is removed from the wafers. Ensuring optimal resource usage and cycle time during the rinse requires a sound understanding and quantitative description of the transport effects that dominate the removal rate of the cleaning chemicals from the surfaces. Multiple processes, such as desorption and re-adsorption, diffusion, migration and convection, all factor into the removal rate of the cleaning chemical during the rinse. Any of these processes can be the removal rate limiting process, the bottleneck of the rinse. In fact, the process limiting the removal rate generally changes as the rinse progresses, offering the opportunity to save resources

  2. Normally-off AlGaN/GaN high-electron-mobility transistor on Si(111) by recessed gate and fluorine plasma treatment

    Science.gov (United States)

    Lin, Jyun-Hao; Huang, Shyh-Jer; Lai, Chao-Hsing; Su, Yan-Kuin

    2016-01-01

    We have studied the efficiency of using both recessed gate and fluorine plasma treatment to achieve normally-off high-electron-mobility transistor (HEMT). It is found that, by a simple recess process, one cannot achieve normally off device with high drain current because of gate leakage problem after inductively coupled plasma (ICP) etching for recessed structure. The proper method is adding fluorine treatment based on recess gate. The normally off GaN HEMTs with recess gate and fluorine treatment show very good performance. It is found that the threshold voltages can be shifted to +1.1 V, and the drain current at VGS - Vth = 2 V and VDS = 20 V was 218 mA/mm.

  3. Approaching Defect-free Amorphous Silicon Nitride by Plasma-assisted Atomic Beam Deposition for High Performance Gate Dielectric

    Science.gov (United States)

    Tsai, Shu-Ju; Wang, Chiang-Lun; Lee, Hung-Chun; Lin, Chun-Yeh; Chen, Jhih-Wei; Shiu, Hong-Wei; Chang, Lo-Yueh; Hsueh, Han-Ting; Chen, Hung-Ying; Tsai, Jyun-Yu; Lu, Ying-Hsin; Chang, Ting-Chang; Tu, Li-Wei; Teng, Hsisheng; Chen, Yi-Chun; Chen, Chia-Hao; Wu, Chung-Lin

    2016-06-01

    In the past few decades, gate insulators with a high dielectric constant (high-k dielectric) enabling a physically thick but dielectrically thin insulating layer, have been used to replace traditional SiOx insulator and to ensure continuous downscaling of Si-based transistor technology. However, due to the non-silicon derivative natures of the high-k metal oxides, transport properties in these dielectrics are still limited by various structural defects on the hetero-interfaces and inside the dielectrics. Here, we show that another insulating silicon compound, amorphous silicon nitride (a-Si3N4), is a promising candidate of effective electrical insulator for use as a high-k dielectric. We have examined a-Si3N4 deposited using the plasma-assisted atomic beam deposition (PA-ABD) technique in an ultra-high vacuum (UHV) environment and demonstrated the absence of defect-related luminescence; it was also found that the electronic structure across the a-Si3N4/Si heterojunction approaches the intrinsic limit, which exhibits large band gap energy and valence band offset. We demonstrate that charge transport properties in the metal/a-Si3N4/Si (MNS) structures approach defect-free limits with a large breakdown field and a low leakage current. Using PA-ABD, our results suggest a general strategy to markedly improve the performance of gate dielectric using a nearly defect-free insulator.

  4. Prospectively Electrocardiogram-Gated High-Pitch Spiral Acquisition Mode Dual-Source CT Coronary Angiography in Patients with High Heart Rates: Comparison with Retrospective Electrocardiogram-Gated Spiral Acquisition Mode

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Kai; Ma, Rui; Wang, Li Jun [Dept. of Radiology, Baotou Central Hospital, Baotou (China); Li, Li Gang; Chen, Jiu Hong [CT BM Clinic Marketing, Siemens Healthcare, Beijing (China)

    2012-11-15

    To assess the image quality and effective radiation dose of prospectively electrocardiogram (ECG)-gated high-pitch spiral acquisition mode (flash mode) of dual-source CT (DSCT) coronary angiography (CTCA) in patients with high heart rates (HRs) as compared with retrospectively ECG-gated spiral acquisition mode. Two hundred and sixty-eight consecutive patients (132 female, mean age: 55 {+-} 11 years) with mean HR > 65 beats per minute (bpm) were prospectively included in this study. The patients were divided into two groups. Collection was performed in group A CTCA using flash mode setting at 20-30% of the R-R interval, and retrospectively ECG-gated spiral acquisition mode in group B. The image noise, contrast-to-noise ratio (CNR), image quality scores, effective radiation dose and influencing factors on image quality between the two groups were assessed. There were no significant differences in image quality scores and proportions of non-diagnostic coronary artery segments between two groups (image quality scores: 1.064 {+-} 0.306 [group A] vs. 1.084 {+-} 0.327 [group B], p = 0.063; proportion of non-diagnostic coronary artery segments: segment-based analysis 1.52% (group A) vs. 1.74% (group B), p = 0.345; patient-based analysis 7.5% (group A) vs. 6.7% (group B), p = 0.812). The estimated radiation dose was 1.0 {+-} 0.16 mSv in group A and 7.1 {+-} 1.05 mSv in group B (p = 0.001). In conclusion, in patients with HRs > 65 bpm without cardiac arrhythmia, the prospectively high-pitch spiral-acquisition mode with image-acquired timing set at 20-30% of the R-R interval provides a similar image quality and low rate of non-diagnostic coronary segments to the retrospectively ECG-gated low-pitch spiral acquisition mode, with significant reduction of radiation exposure.

  5. Quantum logic gates with a two-level trapped ion in a high-finesse cavity beyond the Lamb-Dicke limit

    Energy Technology Data Exchange (ETDEWEB)

    Zheng Xiaojuan [College of Physics and Information Science, Hunan Normal University, Changsha, 410081 (China); Fang Maofa [College of Physics and Information Science, Hunan Normal University, Changsha, 410081 (China); Liao Xiangping [College of Physics and Information Science, Hunan Normal University, Changsha, 410081 (China); Cai Jianwu [College of Physics and Information Science, Hunan Normal University, Changsha, 410081 (China)

    2007-02-14

    In the system with a two-level ion confined both in a linear trap and in a high-Q single-mode cavity, we present a simple scheme to realize the basic two-qubit logic gates such as the quantum phase gate (QPG), the SWAP gate and the controlled-NOT (CNOT) gate beyond the Lamb-Dicke (LD) limit. We realize the three kinds of two-qubit quantum phase gates, i.e. QPG operation involving the cavity mode as well as the vibrational mode of the trapped ion, QPG operation involving the internal states as well as the vibrational mode of the trapped ion and QPG operation involving the internal states of the trapped ion as well as the cavity mode. The controlled-NOT gate can be implemented from a QPG operation through a rotation of the second qubit before and after the QPG operation. We can also perform the SWAP gate operation involving the ionic internal states of the trapped ion and the two-mode bosonic basis. The logic gates involving the cavity mode as well as the vibrational mode of the trapped ion are insensitive to spontaneous emission, and the logic gates involving the internal states as well as the vibrational mode of the trapped ion are insensitive to the decay of the cavity, which is an important feature for the practical implementation of quantum computing. Neither the LD approximation nor the auxiliary atomic level is needed in our scheme. Experimental feasibility for achieving our scheme is also discussed.

  6. High mobility and low density of trap states in dual-solid-gated PbS nanocrystal field-effect transistors.

    Science.gov (United States)

    Nugraha, Mohamad Insan; Häusermann, Roger; Bisri, Satria Zulkarnaen; Matsui, Hiroyuki; Sytnyk, Mykhailo; Heiss, Wolfgang; Takeya, Jun; Loi, Maria Antonietta

    2015-03-25

    Dual-gated PbS nanocrystal field-effect transistors employing SiO2 and Cytop as gate dielectrics are fabricated. The obtained electron mobility (0.2 cm(2) V(-1) s(-1) ) and the high on/off ratio (10(5) -10(6) ), show that the controlled nanocrystal assembly (obtained with self-assembled monolayers), as well as the trap density reduction (using Cytop as dielectric), are crucial steps for the future application of nanocrystals.

  7. Sensing with Advanced Computing Technology: Fin Field-Effect Transistors with High-k Gate Stack on Bulk Silicon.

    Science.gov (United States)

    Rigante, Sara; Scarbolo, Paolo; Wipf, Mathias; Stoop, Ralph L; Bedner, Kristine; Buitrago, Elizabeth; Bazigos, Antonios; Bouvet, Didier; Calame, Michel; Schönenberger, Christian; Ionescu, Adrian M

    2015-05-26

    Field-effect transistors (FETs) form an established technology for sensing applications. However, recent advancements and use of high-performance multigate metal-oxide semiconductor FETs (double-gate, FinFET, trigate, gate-all-around) in computing technology, instead of bulk MOSFETs, raise new opportunities and questions about the most suitable device architectures for sensing integrated circuits. In this work, we propose pH and ion sensors exploiting FinFETs fabricated on bulk silicon by a fully CMOS compatible approach, as an alternative to the widely investigated silicon nanowires on silicon-on-insulator substrates. We also provide an analytical insight of the concept of sensitivity for the electronic integration of sensors. N-channel fully depleted FinFETs with critical dimensions on the order of 20 nm and HfO2 as a high-k gate insulator have been developed and characterized, showing excellent electrical properties, subthreshold swing, SS ∼ 70 mV/dec, and on-to-off current ratio, Ion/Ioff ∼ 10(6), at room temperature. The same FinFET architecture is validated as a highly sensitive, stable, and reproducible pH sensor. An intrinsic sensitivity close to the Nernst limit, S = 57 mV/pH, is achieved. The pH response in terms of output current reaches Sout = 60%. Long-term measurements have been performed over 4.5 days with a resulting drift in time δVth/δt = 0.10 mV/h. Finally, we show the capability to reproduce experimental data with an extended three-dimensional commercial finite element analysis simulator, in both dry and wet environments, which is useful for future advanced sensor design and optimization.

  8. Reverse Gate Bias-Induced Degradation of AlGaN/GaN High Electron Mobility Transistors

    Science.gov (United States)

    2010-09-23

    contributions from hot electrons and self-heating.13,19,20 In this article, we report on the degradation of AlGaN/ GaN HEMTs under step-stressing of...characteristic of the AlGaN/ GaN HEMTs before and after stress. FIG. 6. !Color online" PL spectra of stressed and unstressed devices. FIG. 7. EL images of stressed...high electric fields present under reverse bias stressing of AlGaN/ GaN HEMTs , the devices exhibit a five order of magnitude increase in gate current

  9. High-Contrast Electro-Optic Modulation of a Photonic Crystal Nanocavity by Electrical Gating of Graphene

    CERN Document Server

    Gan, Xuetao; Gao, Yuanda; Mak, Kin Fai; Yao, Xinwen; Li, Luozhou; Szep, Attila; Walker, Dennis; Hone, James; Heinz, Tony F; Englund, Dirk

    2012-01-01

    We demonstrate a high-contrast electro-optic modulation of a photonic crystal nanocavity integrated with an electrically gated monolayer graphene. A high quality (Q) factor air-slot nanocavity design is employed for high overlap between the optical field and graphene sheet. Tuning of graphene's Fermi level up to 0.8 eV enables efficient control of its complex dielectric constant, which allows modulation of the cavity reflection in excess of 10 dB for a swing voltage of only 1.5 V. We also observe a controllable resonance wavelength shift close to 2 nm around a wavelength of 1570 nm and a Q factor modulation in excess of three. These observations allow cavity-enhanced measurements of the graphene complex dielectric constant under different chemical potentials, in agreement with a theoretical model of the graphene dielectric constant under gating. This graphene-based nanocavity modulation demonstrates the feasibility of high-contrast, low-power frequency-selective electro-optic nanocavity modulators in graphene...

  10. High mobility polymer gated organic field effect transistor using zinc phthalocyanine

    Indian Academy of Sciences (India)

    K R Rajesh; V Kannan; M R Kim; Y S Chae; J K Rhee

    2014-02-01

    Organic thin film transistors were fabricated using evaporated zinc phthalocyanine as the active layer. Parylene film prepared by chemical vapour deposition was used as the organic gate insulator. The annealing of the samples was performed at 120°C for 3 h. At room temperature, these transistors exhibit -type conductivity with field-effect mobilities ranging from 0.025–0.037 cm2/Vs and a (on/off) ratio of ∼ 103. The effect of annealing on transistor characteristics is discussed.

  11. Design of High Speed Low Power Reversible Logic Adder Using HNG Gate

    Directory of Open Access Journals (Sweden)

    Manjeet Singh Sankhwar,

    2014-01-01

    Full Text Available Reversibility plays a fundamental role when computations with minimal energy dissipation are considered. In recent years, reversible logic has emerged as one of the most important approaches for power optimization with its application in low power CMOS, optical information processing, quantum computing and nanotechnology. This research proposes a new implementation of adder in reversible logic. The design reduces the number of gate operations compared to the existing adder reversible logic implementations. So, this design gives rise to an implementation with a reduced area and delay. We can use it to construct more complex systems in nanotechnology.

  12. High-Temperature SiC Power Module with Integrated SiC Gate Drivers for Future High-Density Power Electronics Applications

    Energy Technology Data Exchange (ETDEWEB)

    Whitaker, Mr. Bret [APEI, Inc.; Cole, Mr. Zach [APEI, Inc.; Passmore, Mr. Brandon [APEI, Inc.; Martin, Daniel [APEI, Inc.; Mcnutt, Tyler [APEI, Inc.; Lostetter, Dr. Alex [APEI, Inc.; Ericson, Milton Nance [ORNL; Frank, Steven Shane [ORNL; Britton Jr, Charles L [ORNL; Marlino, Laura D [ORNL; Mantooth, Alan [University of Arkansas; Francis, Dr. Matt [University of Arkansas; Lamichhane, Ranjan [University of Arkansas; Shepherd, Dr. Paul [University of Arkansas; Glover, Dr. Michael [University of Arkansas

    2014-01-01

    This paper presents the testing results of an all-silicon carbide (SiC) intelligent power module (IPM) for use in future high-density power electronics applications. The IPM has high-temperature capability and contains both SiC power devices and SiC gate driver integrated circuits (ICs). The high-temperature capability of the SiC gate driver ICs allows for them to be packaged into the power module and be located physically close to the power devices. This provides a distinct advantage by reducing the gate driver loop inductance, which promotes high frequency operation, while also reducing the overall volume of the system through higher levels of integration. The power module was tested in a bridgeless-boost converter to showcase the performance of the module in a system level application. The converter was initially operated with a switching frequency of 200 kHz with a peak output power of approximately 5 kW. The efficiency of the converter was then evaluated experimentally and optimized by increasing the overdrive voltage on the SiC gate driver ICs. Overall a peak efficiency of 97.7% was measured at 3.0 kW output. The converter s switching frequency was then increased to 500 kHz to prove the high frequency capability of the power module was then pushed to its limits and operated at a switching frequency of 500 kHz. With no further optimization of components, the converter was able to operate under these conditions and showed a peak efficiency of 95.0% at an output power of 2.1 kW.

  13. Investigation of high-quality ultra-thin LaAlO{sub 3} films as high-k gate dielectrics

    Energy Technology Data Exchange (ETDEWEB)

    Lu, X B [National Laboratory of Solid State Microstructures, Nanjing University, Hankou Road 22, Nanjing 210093 (China); Liu, Z G [National Laboratory of Solid State Microstructures, Nanjing University, Hankou Road 22, Nanjing 210093 (China); Zhang, X [Institute of Microelectronics, Peking University, Beijing 100871 (China); Huang, R [Institute of Microelectronics, Peking University, Beijing 100871 (China); Zhou, H W [Digital DNA Laboratories, Motorola Inc. (China); Wang, X P [Digital DNA Laboratories, Motorola Inc.(China); Nguyen, Bich-Yen [Digital DNA Laboratories, Motorola Inc. (China)

    2003-12-07

    We have studied the formation of a high-quality LaAlO{sub 3} (LAO) film directly on silicon substrates by the pulsed laser deposition method as a novel high-k gate dielectric. The LAO films can remain amorphous at temperatures up to 850 deg. C. An atomic force microscopy study indicated a very smooth surface of the deposited films with a rms of 0.14 nm for an 8 nm LAO film. The structures and electrical properties of metal-dielectric-semiconductor (Pt/LAO/Si) capacitors were investigated with LAO films deposited under different ambient conditions. High-resolution transmission electron microscopy indicated that interfacial reactions often occur for films of LAO deposited under oxygen ambient. A small effective oxide thickness of 1.2 nm was obtained for those films deposited under 20 Pa nitrogen ambient, with the corresponding leakage current density 17.1 mA cm{sup -2} at +1 V gate voltage. It is proposed that amorphous LAO films are a novel promising alternative high-k gate dielectric material in future ultra-large scale integrated devices.

  14. Design of a High Precision, Wide Ranged Analog Clock Generator with Field Programmability Using Floating-Gate Transistors

    Directory of Open Access Journals (Sweden)

    Prem Pyara

    2010-09-01

    Full Text Available This paper presents a circuit of a high-precision, wide ranged, analog clock generator with on-chipprogrammability feature using Floating-gate transistors. The programmable oscillator can attain acontinuous range of time-periods lying in the programming precision range of Floating Gates. Thecircuit consists of two sub circuits: Current Generator circuit and Wave Generator circuit. The current ofcurrent generator circuit is programmable and mirrored to the wave generator to generate the desiredsquare wave. The topology is well suited to applications like clocking high performance ADCs and DACsas well as used as the internal clock in structured analog CMOS designs. A simulation model of thecircuit was built in T-Spice, 0.35μm CMOS process. The circuit results in finely tuned clock withprogrammability precision of about 13bit [1]. Simulation results show high amount of temperatureinsensitivity (0.507ns/°C for a large range of thermal conditions. The proposed circuit can compensateany change in temperature. The circuit design can be operated at low supply voltage i.e., 1v.

  15. Design of a High Precision, Wide Ranged Analog Clock Generator with Field Programmability Using Floating-Gate Transistors

    Directory of Open Access Journals (Sweden)

    Garima Kapur

    2010-09-01

    Full Text Available This paper presents a circuit of a high-precision, wide ranged, analog clock generator with on-chip programmability feature using Floating-gate transistors. The programmable oscillator can attain acontinuous range of time-periods lying in the programming precision range of Floating Gates. The circuit consists of two sub circuits: Current Generator circuit and Wave Generator circuit. The current of current generator circuit is programmable and mirrored to the wave generator to generate the desired square wave. The topology is well suited to applications like clocking high performance ADCs and DACsas well as used as the internal clock in structured analog CMOS designs. A simulation model of the circuit was built in T-Spice, 0.35μm CMOS process. The circuit results in finely tuned clock with programmability precision of about 13 bit [1]. Simulation results show high amount of temperature insensitivity (0.507 ns/°C for a large range of thermal conditions. The proposed circuit can compensate any change in temperature. The circuit design can be operated at low supply voltage i.e., 1v.

  16. Three homologous subunits form a high affinity peptide-gated ion channel in Hydra

    DEFF Research Database (Denmark)

    Dürrnagel, Stefan; Kuhn, Anne; Tsiairis, Charisios D

    2010-01-01

    properties, like a low Na(+) selectivity and a low amiloride affinity, that are different from other channels of the DEG/ENaC gene family, suggesting that a component of the native Hydra channel might still be lacking. Here, we report the cloning of a new ion channel subunit from Hydra, HyNaC5. The new......Recently, three ion channel subunits of the degenerin (DEG)/epithelial Na(+) channel (ENaC) gene family have been cloned from the freshwater polyp Hydra magnipapillata, the Hydra Na(+) channels (HyNaCs) 2-4. Two of them, HyNaC2 and HyNaC3, co-assemble to form an ion channel that is gated...... by the neuropeptides Hydra-RFamides I and II. The HyNaC2/3 channel is so far the only cloned ionotropic receptor from cnidarians and, together with the related ionotropic receptor FMRFamide-activated Na(+) channel (FaNaC) from snails, the only known peptide-gated ionotropic receptor. The HyNaC2/3 channel has pore...

  17. Quantum Interference Phenomena and Novel Switching in Split Gate High Electron Mobility Transistors.

    Science.gov (United States)

    Wu, Jong-Ching

    Nanometer scales electronic channels with and without a discontinuity were made in modulation-doped AlGaAs/GaAs heterojunctions using a split-gate technique. Quantum interference phenomena in an electron cavity, and fast switching behavior due to hot electron effects in a lateral double potential barrier structure were explored. First, one-dimensional channels with a double bend discontinuity were examined in the mK temperature range. Low-field ac-conductance measurements have evidenced quantum wave guide effects: resonant features were observed in the one-dimensional conductance plateaus in which the number of peaks was directly related to the geometry of the double bend. Temperature and magnetic field studies, along with a standing wave model have provided a better understanding of quantum interference phenomena in electron wave guide and cavity structures. Secondly, a structure containing two cascaded double bend discontinuities was studied. The structure behaves as a constricted cavity coupling two point-contacts, in which the depletion by the split gate was used to form and control the lateral double potential barriers. The low temperature source-drain characteristics exhibited a pronounced S-shaped negative differential conductance that can be attributed to a nonlinear electron temperature effect along the conducting path. The data presented show two types of conducting state: electron tunneling in the off state and hot electron conduction (thermionic emission) in the on state. The estimated switching speed of the device could be as fast as 5 ps due to short transit time.

  18. Studies on the reliability of ni-gate aluminum gallium nitride / gallium nitride high electron mobility transistors using chemical deprocessing

    Science.gov (United States)

    Whiting, Patrick Guzek

    Aluminum Gallium Nitride / Gallium Nitride High Electron Mobility Transistors are becoming the technology of choice for applications where hundreds of volts need to be applied in a circuit at frequencies in the hundreds of gigahertz, such as microwave communications. However, because these devices are very new, their reliability in the field is not well understood, partly because of the stochastic nature of the defects which form as a result of their operation. Many analytical techniques are not well suited to the analysis of these defects because they sample regions of the device which are either too small or too large for accurate observation. The use of chemical deprocessing in addition to surface-sensitive analysis techniques such as Scanning Electron Microscopy and Scanning Probe Microscopy can be utilized in the analysis of defect formation in devices formed with nickel gates. Hydrofluoric acid is used to etch the passivation nitride which covers the semiconducting layer of the transistor. A metal etch utilizing FeCN/KI is used to etch the ohmic and gate contacts of the device and a long exposure in various solvent solutions is used to remove organic contaminants, exposing the surface of the semiconducting layer for analysis. Deprocessing was used in conjunction with a variety of metrology techniques to analyze three different defects. One of these defects is a nanoscale crack which emanates from metal inclusions formed during alloying of the ohmic contacts of the device prior to use in the field, could impact the yield of production-level manufacturing of these devices. This defect also appears to grow, in some cases, during electrostatic stressing. Another defect, a native oxide at the surface of the semiconducting layer which appears to react in the presence of an electric field, has not been observed before during post-mortem analysis of degraded devices. It could play a major part in the degredation of the gate contact during high-field, off

  19. Metal-oxide assisted surface treatment of polyimide gate insulators for high-performance organic thin-film transistors.

    Science.gov (United States)

    Kim, Sohee; Ha, Taewook; Yoo, Sungmi; Ka, Jae-Won; Kim, Jinsoo; Won, Jong Chan; Choi, Dong Hoon; Jang, Kwang-Suk; Kim, Yun Ho

    2017-06-14

    We developed a facile method for treating polyimide-based organic gate insulator (OGI) surfaces with self-assembled monolayers (SAMs) by introducing metal-oxide interlayers, called the metal-oxide assisted SAM treatment (MAST). To create sites for surface modification with SAM materials on polyimide-based OGI (KPI) surfaces, the metal-oxide interlayer, here amorphous alumina (α-Al2O3), was deposited on the KPI gate insulator using spin-coating via a rapid sol-gel reaction, providing an excellent template for the formation of a high-quality SAM with phosphonic acid anchor groups. The SAM of octadecylphosphonic acid (ODPA) was successfully treated by spin-coating onto the α-Al2O3-deposited KPI film. After the surface treatment by ODPA/α-Al2O3, the surface energy of the KPI thin film was remarkably decreased and the molecular compatibility of the film with an organic semiconductor (OSC), 2-decyl-7-phenyl-[1]benzothieno[3,2-b][1]benzothiophene (Ph-BTBT-C10), was increased. Ph-BTBT-C10 molecules were uniformly deposited on the treated gate insulator surface and grown with high crystallinity, as confirmed by atomic force microscopy (AFM) and X-ray diffraction (XRD) analysis. The mobility of Ph-BTBT-C10 thin-film transistors (TFTs) was approximately doubled, from 0.56 ± 0.05 cm(2) V(-1) s(-1) to 1.26 ± 0.06 cm(2) V(-1) s(-1), after the surface treatment. The surface treatment of α-Al2O3 and ODPA significantly decreased the threshold voltage from -21.2 V to -8.3 V by reducing the trap sites in the OGI and improving the interfacial properties with the OSC. We suggest that the MAST method for OGIs can be applied to various OGI materials lacking reactive sites using SAMs. It may provide a new platform for the surface treatment of OGIs, similar to that of conventional SiO2 gate insulators.

  20. Improving a high-efficiency, gated spectrometer for x-ray Thomson scattering experiments at the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Döppner, T., E-mail: doeppner1@llnl.gov; Bachmann, B.; Emig, J.; Hardy, M.; Kalantar, D. H.; Kritcher, A. L.; Landen, O. L.; Ma, T.; Wood, R. D. [Lawrence Livermore National Laboratory, Livermore, California 94720 (United States); Kraus, D.; Saunders, A. M. [University of California, Berkeley, California 94720 (United States); Neumayer, P. [Gesellschaft für Schwerionenphysik, Darmstadt (Germany); Falcone, R. W. [University of California, Berkeley, California 94720 (United States); Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Fletcher, L. B. [SLAC National Accelerator Laboratory, Menlo Park, California 94720 (United States)

    2016-11-15

    We are developing x-ray Thomson scattering for applications in implosion experiments at the National Ignition Facility. In particular we have designed and fielded MACS, a high-efficiency, gated x-ray spectrometer at 7.5–10 keV [T. Döppner et al., Rev. Sci. Instrum. 85, 11D617 (2014)]. Here we report on two new Bragg crystals based on Highly Oriented Pyrolytic Graphite (HOPG), a flat crystal and a dual-section cylindrically curved crystal. We have performed in situ calibration measurements using a brass foil target, and we used the flat HOPG crystal to measure Mo K-shell emission at 18 keV in 2nd order diffraction. Such high photon energy line emission will be required to penetrate and probe ultra-high-density plasmas or plasmas of mid-Z elements.

  1. Temperature- and voltage-dependent trap generation model in high-k metal gate MOS device with percolation simulation

    Science.gov (United States)

    Xu, Hao; Yang, Hong; Wang, Yan-Rong; Wang, Wen-Wu; Luo, Wei-Chun; Qi, Lu-Wei; Li, Jun-Feng; Zhao, Chao; Chen, Da-Peng; Ye, Tian-Chun

    2016-08-01

    High-k metal gate stacks are being used to suppress the gate leakage due to tunneling for sub-45 nm technology nodes. The reliability of thin dielectric films becomes a limitation to device manufacturing, especially to the breakdown characteristic. In this work, a breakdown simulator based on a percolation model and the kinetic Monte Carlo method is set up, and the intrinsic relation between time to breakdown and trap generation rate R is studied by TDDB simulation. It is found that all degradation factors, such as trap generation rate time exponent m, Weibull slope β and percolation factor s, each could be expressed as a function of trap density time exponent α. Based on the percolation relation and power law lifetime projection, a temperature related trap generation model is proposed. The validity of this model is confirmed by comparing with experiment results. For other device and material conditions, the percolation relation provides a new way to study the relationship between trap generation and lifetime projection. Project supported by the National High Technology Research and Development Program of China (Grant No. SS2015AA010601), the National Natural Science Foundation of China (Grant Nos. 61176091 and 61306129), and the Opening Project of Key Laboratory of Microelectronics Devices & Integrated Technology, Institute of MicroElectronics of Chinese Academy of Sciences.

  2. Microscopic signature of insulator-to-metal transition in highly doped semicrystalline conducting polymers in ionic-liquid-gated transistors

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Hisaaki, E-mail: htanaka@nuap.nagoya-u.ac.jp; Nishio, Satoshi; Ito, Hiroshi; Kuroda, Shin-ichi [Department of Applied Physics, Nagoya University, Chikusa, Nagoya 464-8603 (Japan)

    2015-12-14

    Electronic state of charge carriers, in particular, in highly doped regions, in thin-film transistors of a semicrystalline conducting polymer poly(2,5-bis(3-alkylthiophene-2-yl)thieno[3,2-b]thiophene), has been studied by using field-induced electron spin resonance (ESR) spectroscopy. By adopting an ionic-liquid gate insulator, a gate-controlled reversible electrochemical hole-doping of the polymer backbone is achieved, as confirmed from the change of the optical absorption spectra. The edge-on molecular orientation in the pristine film is maintained even after the electrochemical doping, which is clarified from the angular dependence of the g value. As the doping level increases, spin 1/2 polarons transform into spinless bipolarons, which is demonstrated from the spin-charge relation showing a spin concentration peak around 1%, contrasting to the monotonic increase in the charge concentration. At high doping levels, a drastic change in the linewidth anisotropy due to the generation of conduction electrons is observed, indicating the onset of metallic state, which is also supported by the temperature dependence of the spin susceptibility and the ESR linewidth. Our results suggest that semicrystalline conducting polymers become metallic with retaining their molecular orientational order, when appropriate doping methods are chosen.

  3. Efficient III-Nitride MIS-HEMT devices with highgate dielectric for high-power switching boost converter circuits

    Science.gov (United States)

    Mohanbabu, A.; Mohankumar, N.; Godwin Raj, D.; Sarkar, Partha; Saha, Samar K.

    2017-03-01

    The paper reports the results of a systematic theoretical study on efficient recessed-gate, double-heterostructure, and normally-OFF metal-insulator-semiconductor high-electron mobility transistors (MIS-HEMTs), HfAlOx/AlGaN on Al2O3 substrate. In device architecture, a thin AlGaN layer is used in the AlGaN graded barrier MIS-HEMTs that offers an excellent enhancement-mode device operation with threshold voltage higher than 5.3 V and drain current above 0.64 A/mm along with high on-current/off-current ratio over 107 and subthreshold slope less than 73 mV/dec. In addition, a high OFF-state breakdown voltage of 1200 V is achieved for a device with a gate-to-drain distance and field-plate length of 15 μm and 5.3 μm, respectively at a drain current of 1 mA/mm with a zero gate bias, and the substrate grounded. The numerical device simulation results show that in comparison to a conventional AlGaN/GaN MIS-HEMT of similar design, a graded barrier MIS-HEMT device exhibits a better interface property, remarkable suppression of leakage current, and a significant improvement of breakdown voltage for HfAlOx gate dielectric. Finally, the benefit of HfAlOx graded-barrier AlGaN MIS-HEMTs based switching devices is evaluated on an ultra-low-loss converter circuit.

  4. High-performance enhancement-mode Al2O3/InAlGaN/GaN MOS high-electron mobility transistors with a self-aligned gate recessing technology

    Science.gov (United States)

    Zhang, Kai; Kong, Cen; Zhou, Jianjun; Kong, Yuechan; Chen, Tangsheng

    2017-02-01

    The paper reports high-performance enhancement-mode MOS high-electron mobility transistors (MOS-HEMTs) based on a quaternary InAlGaN barrier. Self-aligned gate technology is used for gate recessing, dielectric deposition, and gate electrode formation. An improved digital recessing process is developed, and an Al2O3 gate dielectric grown with O2 plasma is used. Compared to results with AlGaN barrier, the fabricated E-mode MOS-HEMT with InAlGaN barrier delivers a record output current density of 1.7 A/mm with a threshold voltage (V TH) of 1.5 V, and a small on-resistance (R on) of 2.0 Ω·mm. Excellent V TH hysteresis and greatly improved gate leakage characteristics are also demonstrated.

  5. Investigation of passivation effects in AlGaN/GaN metal-insulator-semiconductor high electron-mobility transistor by gate-drain conductance dispersion study

    Institute of Scientific and Technical Information of China (English)

    Bi Zhi-Wei; Chang Yong-Ming; Li Zhi-Ming; Mei Nan; Hu Zhen-Hua; Mao Wei; Hao Yue; Feng Qian; Cao Yan-Rong; Gao Zhi-Yuan; Zhang Jin-Cheng; Ma Xiao-Hua

    2011-01-01

    This paper studies the drain current collapse of AlGaN/GaN metal-insulator-semiconductor high electron-mobility transistors(MIS-HEMTs)with NbAlO dielectric by applying dual-pulsed stress to the gate and drain of the device.For NbAlO MIS-HEMT,smaller current collapse is found,especially when the gate static voltage is-8 V.Through a thorough study of the gate-drain conductance dispersion,it is found that the growth of NbAlO can reduce the trap density of the AlGaN surface.Therefore,fewer traps can be filled by gate electrons,and hence the depletion effect in the channel is suppressed effectively.It is proved that the NbAlO gate dielectric can not only decrease gate leakage current but also passivate the AlGaN surface effectively,and weaken the current collapse effect accordingly.

  6. A 16 channel high resolution (Digital Converter in a Field Programmable Gate Array

    Science.gov (United States)

    Ugur, C.; Bayer, E.; Kurz, N.; Traxler, M.

    2012-02-01

    A 16-channel Time-to-Digital Converter (TDC) was implemented in a general purpose Field-Programmable Gate Array (FPGA). The fine time calculations are achieved by using the dedicated carry-chain lines. The coarse counter defines the coarse time stamp. In order to overcome the negative effects of temperature and power supply dependency bin-by-bin calibration is applied. The time interval measurements are done using 2 channels. The time resolution of channels are calculated for 1 clock cycle and a minimum of 10.3 ps RMS on two channels, yielding 7.3 ps RMS (10.3 ps/√2) on a single channel is achieved.

  7. High temperature performance of Si:HfO2 based long channel Double Gate Ferroelectric Junctionless Transistors

    Science.gov (United States)

    Mehta, Hema; Kaur, Harsupreet

    2017-03-01

    In this work, we present a study that explores the suitability of Double Gate Ferroelectric Junctionless Transistor (DGFJL) incorporating Si:HfO2 for high temperature applications. At present, very few studies are focussed on Si:HfO2 to investigate its integrability in the present CMOS design space. Therefore, in the present study, using analytical modeling and TCAD simulations, it is demonstrated that Si:HfO2 based DGFJL exhibits superior performance in terms of substantial gain, reduced leakage currents, improved current drivability and high Ion/Ioff ratio at elevated temperatures as compared to the DGJL counterpart. The study, thus, highlights the fact that DGFJL is a potential candidate for device applications at high temperatures.

  8. A High Breakdown Voltage A1GaN/GaN MOSHEMT Using Thermal Oxidized Al-Ti as the Gate Insulator

    Institute of Scientific and Technical Information of China (English)

    ZHOU Bin; WANG Jin-Yan; MENG Di; LIN Shu-Xun; FANG Min; DONG Zhi-Hua; YU Min; HAOYi-Long; Cheng P. WEN

    2011-01-01

    Direct oxidation of composite Al/Ti metal films as gate insulators for AlGaN/GaN metal-oxide-semiconductor high-electron mobility transistors (MOSHEMTs/HEMTs) is successfully realized.The devices fabricated with this novel process exhibit four orders of magnitude reduction in gate leakage current and remarkable breakdown voltage (Vbr =490 V vs 88 V for normal HEMT) improvement,compared with conventional Schottky-gate HEMTs.Furthermore,the transconductance of the MOSHEMT is only slightly lower (2.6%) than that of Schottky-gate HEMTs and have a wider full width of half maximum.The notable enhancement in device performance renders this new process highly promising for GaN-based microwave power amplifier applications in communication and radar systems.AlGaN/GaN high-electron mobility transistors (HEMTs) are expected to be applied in the highfrequency and high-power area because of their excellent properties.AlGaN/GaN has,for example,a wide energy band gap (3.39eV),high density (up to 1013 cm-2) two-dimensional electron gas (2DEG)and a high saturation electron velocity.Due to the unavailability of native oxide,Schottky-contact gates are commonly adopted in AlGaN/GaN HEMTs.%Direct oxidation of composite Al/Ti metal films as gate insulators for AlGaN/GaN metal-oxide-semiconductor high-electron mobility transistors (MOSHEMTs/HEMTs) is successfully realized. The devices fabricated with this novel process exhibit four orders of magnitude reduction in gate leakage current and remarkable breakdown voltage (Vbr = 490 V vs 88 V for normal HEMT) improvement, compared with conventional Schottky-gate HEMTs. Furthermore, the transconductance of the MOSHEMT is only slightly lower (2.6%) than that of Schottky-gate HEMTs and have a wider full width of half maximum. The notable enhancement in device performance renders this new process highly promising for GaN-based microwave power amplifier applications in communication and radar systems.

  9. Characterization of high-dose and high-energy implanted gate and source diode and analysis of lateral spreading of p gate profile in high voltage SiC static induction transistors

    Science.gov (United States)

    Onose, Hidekatsu; Kobayashi, Yutaka; Onuki, Jin

    2017-03-01

    The effect of the p gate dose on the characteristics of the gate-source diode in SiC static induction transistors (SIT) was investigated. It was found that a dose of 1.5 × 1014 cm-2 yields a pn junction breakdown voltage higher than 60 V and good forward characteristics. A normally on SiC SIT was fabricated and demonstrated. A blocking voltage higher than 2.0 kV at a gate-source voltage of -50 V and on-resistance of 70 mΩ cm2 were obtained. Device simulations were performed to investigate the effect of the lateral spreading. By comparing the measured I-V curves with simulation results, the lateral spreading factor was estimated to be about 0.5. The lateral spreading detrimentally affected the electrical properties of the SIT made using implantations at energies higher than 1 MeV.

  10. Expert Oracle GoldenGate

    CERN Document Server

    Prusinski, Ben; Chung, Richard

    2011-01-01

    Expert Oracle GoldenGate is a hands-on guide to creating and managing complex data replication environments using the latest in database replication technology from Oracle. GoldenGate is the future in replication technology from Oracle, and aims to be best-of-breed. GoldenGate supports homogeneous replication between Oracle databases. It supports heterogeneous replication involving other brands such as Microsoft SQL Server and IBM DB2 Universal Server. GoldenGate is high-speed, bidirectional, highly-parallelized, and makes only a light impact on the performance of databases involved in replica

  11. A self-amplified transistor immunosensor under dual gate operation: highly sensitive detection of hepatitis B surface antigen

    Science.gov (United States)

    Lee, I.-K.; Jeun, M.; Jang, H.-J.; Cho, W.-J.; Lee, K. H.

    2015-10-01

    Ion-sensitive field-effect transistors (ISFETs), although they have attracted considerable attention as effective immunosensors, have still not been adopted for practical applications owing to several problems: (1) the poor sensitivity caused by the short Debye screening length in media with high ion concentration, (2) time-consuming preconditioning processes for achieving the highly-diluted media, and (3) the low durability caused by undesirable ions such as sodium chloride in the media. Here, we propose a highly sensitive immunosensor based on a self-amplified transistor under dual gate operation (immuno-DG ISFET) for the detection of hepatitis B surface antigen. To address the challenges in current ISFET-based immunosensors, we have enhanced the sensitivity of an immunosensor by precisely tailoring the nanostructure of the transistor. In the pH sensing test, the immuno-DG ISFET showed superior sensitivity (2085.53 mV per pH) to both standard ISFET under single gate operation (58.88 mV per pH) and DG ISFET with a non-tailored transistor (381.14 mV per pH). Moreover, concerning the detection of hepatitis B surface antigens (HBsAg) using the immuno-DG ISFET, we have successfully detected trace amounts of HBsAg (22.5 fg mL-1) in a non-diluted 1× PBS medium with a high sensitivity of 690 mV. Our results demonstrate that the proposed immuno-DG ISFET can be a biosensor platform for practical use in the diagnosis of various diseases.Ion-sensitive field-effect transistors (ISFETs), although they have attracted considerable attention as effective immunosensors, have still not been adopted for practical applications owing to several problems: (1) the poor sensitivity caused by the short Debye screening length in media with high ion concentration, (2) time-consuming preconditioning processes for achieving the highly-diluted media, and (3) the low durability caused by undesirable ions such as sodium chloride in the media. Here, we propose a highly sensitive immunosensor

  12. Qualification of a high-efficiency, gated spectrometer for x-ray Thomson scattering on the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Döppner, T.; Kritcher, A. L.; Bachmann, B.; Burns, S.; Hawreliak, J.; House, A.; Landen, O. L.; LePape, S.; Ma, T.; Pak, A.; Swift, D. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Neumayer, P. [Gesellschaft für Schwerionenphysik, 64291 Darmstadt (Germany); Kraus, D. [University of California, Berkeley, California 94720 (United States); Falcone, R. W. [University of California, Berkeley, California 94720 (United States); Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Glenzer, S. H. [SLAC National Accelerator Laboratory, Menlo Park, California 94309 (United States)

    2014-11-15

    We have designed, built, and successfully fielded a highly efficient and gated Bragg crystal spectrometer for x-ray Thomson scattering measurements on the National Ignition Facility (NIF). It utilizes a cylindrically curved Highly Oriented Pyrolytic Graphite crystal. Its spectral range of 7.4–10 keV is optimized for scattering experiments using a Zn He-α x-ray probe at 9.0 keV or Mo K-shell line emission around 18 keV in second diffraction order. The spectrometer has been designed as a diagnostic instrument manipulator-based instrument for the NIF target chamber at the Lawrence Livermore National Laboratory, USA. Here, we report on details of the spectrometer snout, its novel debris shield configuration and an in situ spectral calibration experiment with a Brass foil target, which demonstrated a spectral resolution of E/ΔE = 220 at 9.8 keV.

  13. Liquid-Gated High Mobility and Quantum Oscillation of the Two-Dimensional Electron Gas at an Oxide Interface.

    Science.gov (United States)

    Zeng, Shengwei; Lü, Weiming; Huang, Zhen; Liu, Zhiqi; Han, Kun; Gopinadhan, Kalon; Li, Changjian; Guo, Rui; Zhou, Wenxiong; Ma, Haijiao Harsan; Jian, Linke; Venkatesan, Thirumalai; Ariando

    2016-04-26

    Electric field effect in electronic double layer transistor (EDLT) configuration with ionic liquids as the dielectric materials is a powerful means of exploring various properties in different materials. Here, we demonstrate the modulation of electrical transport properties and extremely high mobility of two-dimensional electron gas at LaAlO3/SrTiO3 (LAO/STO) interface through ionic liquid-assisted electric field effect. With a change of the gate voltages, the depletion of charge carrier and the resultant enhancement of electron mobility up to 19 380 cm(2)/(V s) are realized, leading to quantum oscillations of the conductivity at the LAO/STO interface. The present results suggest that high-mobility oxide interfaces, which exhibit quantum phenomena, could be obtained by ionic liquid-assisted field effect.

  14. Correlation of low levels of nitrite and high levels of fetal hemoglobin in patients with sickle cell disease at baseline

    Directory of Open Access Journals (Sweden)

    Darcielle Bruna Dias Elias

    2012-01-01

    Full Text Available BACKGROUND: Sickle cell disease is a hemoglobinopathy characterized by hemolytic anemia, increased susceptibility to infections and recurrent vaso-occlusive crises that reduces the quality of life of sufferers. OBJECTIVE: To evaluate the correlation of the levels of lactate dehydrogenase, malonaldehyde and nitrite to fetal hemoglobin in patients with sickle cell disease not under treatment with hydroxyurea in outpatients at a university hospital in Fortaleza, Ceará, Brazil. METHODS: Forty-four patients diagnosed with sickle cell disease were enrolled at baseline. Diagnosis was confirmed by evaluating the beta globin gene using polymerase chain reaction-restriction fragment length polymorphism. The concentration of fetal hemoglobin was obtained by high-performance liquid chromatography. Serum levels of nitrite, malonaldehyde and lactate dehydrogenase were measured by biochemical methods. RESULTS: Significantly higher levels of lactate dehydrogenase, nitrite and malonaldehyde were observed in patients with sickle cell disease compared to a control group. The study of the correlation between fetal hemoglobin levels and these variables showed a negative correlation with nitrite levels. No correlation was found between fetal hemoglobin and malonaldehyde or lactate dehydrogenase. When the study population was stratified according to fetal hemoglobin levels, a decrease in the levels of nitrite was observed with higher levels of fetal hemoglobin (p-value = 0.0415. CONCLUSION: The results show that, similar to fetal hemoglobin levels, the concentration of nitrite can predict the clinical course of the disease, but should not be used alone as a modulator of prognosis in patients with sickle cell disease.

  15. Characterization of Al2O3/GaN/AlGaN/GaN metal-insulator-semiconductor high electron mobility transistors with different gate recess depths

    Institute of Scientific and Technical Information of China (English)

    Ma Xiao-Hua; Pan Cai-Yuan; Yang Li-Yuan; Yu Hui-You; Yang Ling; Quan Si; Wang Hao; Zhang Jin-Cheng; Hao Yue

    2011-01-01

    In this paper, in order to solve the interface-trap issue and enhance the transconductance induced by high-k dielectric in metal-insulator-semiconductor (MIS) high electron mobility transistors (HEMTs), we demonstrate better performances of recessed-gate Al2O3 MIS-HEMTs which are fabricated by Fluorine-based Si3N4 etching and chlorinebased AlGaN etching with three etching times (15 s, 17 s and 19 s). The gate leakage current of MIS-HEMT is about three orders of magnitude lower than that of AlGaN/GaN HEMT. Through the recessed-gate etching, the transconductance increases effectively. When the recessed-gate depth is 1.02 nm, the best interface performance with γit=(0.20-1.59) μs and Dit=(0.55-1.08)×1012 cm-2·eV-1 can be obtained. After chlorine-based etching, the interface trap density reduces considerably without generating any new type of trap. The accumulated chlorine ions and the N vacancies in the AlGaN surface caused by the plasma etching can degrade the breakdown and the high frequency performances of devices. By comparing the characteristics of recessed-gate MIS-HEMTs with different etching times, it is found that a low power chlorine-based plasma etching for a short time (15 s in this paper) can enhance the performances of MIS-HEMTs effectively.

  16. A self-amplified transistor immunosensor under dual gate operation: highly sensitive detection of hepatitis B surface antigen.

    Science.gov (United States)

    Lee, I-K; Jeun, M; Jang, H-J; Cho, W-J; Lee, K H

    2015-10-28

    Ion-sensitive field-effect transistors (ISFETs), although they have attracted considerable attention as effective immunosensors, have still not been adopted for practical applications owing to several problems: (1) the poor sensitivity caused by the short Debye screening length in media with high ion concentration, (2) time-consuming preconditioning processes for achieving the highly-diluted media, and (3) the low durability caused by undesirable ions such as sodium chloride in the media. Here, we propose a highly sensitive immunosensor based on a self-amplified transistor under dual gate operation (immuno-DG ISFET) for the detection of hepatitis B surface antigen. To address the challenges in current ISFET-based immunosensors, we have enhanced the sensitivity of an immunosensor by precisely tailoring the nanostructure of the transistor. In the pH sensing test, the immuno-DG ISFET showed superior sensitivity (2085.53 mV per pH) to both standard ISFET under single gate operation (58.88 mV per pH) and DG ISFET with a non-tailored transistor (381.14 mV per pH). Moreover, concerning the detection of hepatitis B surface antigens (HBsAg) using the immuno-DG ISFET, we have successfully detected trace amounts of HBsAg (22.5 fg mL(-1)) in a non-diluted 1× PBS medium with a high sensitivity of 690 mV. Our results demonstrate that the proposed immuno-DG ISFET can be a biosensor platform for practical use in the diagnosis of various diseases.

  17. Low Threshold Voltage and High Mobility N-Channel Metal-Oxide-Semiconductor Field-Effect Transistor Using Hf-Si/HfO2 Gate Stack Fabricated by Gate-Last Process

    Science.gov (United States)

    Ando, Takashi; Hirano, Tomoyuki; Tai, Kaori; Yamaguchi, Shinpei; Yoshida, Shinichi; Iwamoto, Hayato; Kadomura, Shingo; Watanabe, Heiji

    2010-01-01

    Systematic characterization of Hf-Si/HfO2 gate stacks revealed two mobility degradation modes. One is carrier scattering by fixed charges and/or trapped charges induced by the crystallization in the thick HfO2 case (inversion oxide thickness, Tinv> 1.6 nm). The other is the Hf penetration into the interfacial layer with the Si substrate in the thin HfO2 case (Tinv< 1.6 nm) for the Hf-rich electrode. It was demonstrated that careful optimization of the HfO2 thickness and the Hf-Si composition can suppress both modes. As a result, a high electron mobility equivalent to that of n+polycrystalline silicon (poly-Si)/SiO2 (248 cm2 V-1 s-1 at Eeff=1 MV/cm) was obtained at Tinv of 1.47 nm. Moreover, the effective work function of the optimized Hf-Si/HfO2 gate stack is located within 50 mV from the Si band edge (Ec). An extremely high Ion of 1165 µA/µm (at Ioff = 81 nA/µm) at Vdd=1.0 V was demonstrated for a 45 nm gate n-channel metal-oxide-semiconductor field-effect transistor (n-MOSFET) without strain enhanced technology.

  18. Gated pinhole camera imaging of the high-energy ions emitted by a discharge produced Sn plasma for extreme ultraviolet generation

    NARCIS (Netherlands)

    Gielissen, K.; Sidelnikov, Y.; Glushkov, D.; Soer, W.A.; Banine V.Y.; Van der Mullen, J.J.A.M.

    2010-01-01

    The origin and nature of the high-energy ions emitted by a dischargeproduced plasma source are studied using gated pinhole camera imaging. Time-of-flight analysis in combination with Faraday cup measurements enables characterization of the high-velocity component of theionic debris. The use of an

  19. Cardiac-respiratory self-gated cine ultra-short echo time (UTE) cardiovascular magnetic resonance for assessment of functional cardiac parameters at high magnetic fields.

    Science.gov (United States)

    Hoerr, Verena; Nagelmann, Nina; Nauerth, Arno; Kuhlmann, Michael T; Stypmann, Jörg; Faber, Cornelius

    2013-07-04

    To overcome flow and electrocardiogram-trigger artifacts in cardiovascular magnetic resonance (CMR), we have implemented a cardiac and respiratory self-gated cine ultra-short echo time (UTE) sequence. We have assessed its performance in healthy mice by comparing the results with those obtained with a self-gated cine fast low angle shot (FLASH) sequence and with echocardiography. 2D self-gated cine UTE (TE/TR = 314 μs/6.2 ms, resolution: 129 × 129 μm, scan time per slice: 5 min 5 sec) and self-gated cine FLASH (TE/TR = 3 ms/6.2 ms, resolution: 129 × 129 μm, scan time per slice: 4 min 49 sec) images were acquired at 9.4 T. Volume of the left and right ventricular (LV, RV) myocardium as well as the end-diastolic and -systolic volume was segmented manually in MR images and myocardial mass, stroke volume (SV), ejection fraction (EF) and cardiac output (CO) were determined. Statistical differences were analyzed by using Student t test and Bland-Altman analyses. Self-gated cine UTE provided high quality images with high contrast-to-noise ratio (CNR) also for the RV myocardium (CNRblood-myocardium = 25.5 ± 7.8). Compared to cine FLASH, susceptibility, motion, and flow artifacts were considerably reduced due to the short TE of 314 μs. The aortic valve was clearly discernible over the entire cardiac cycle. Myocardial mass, SV, EF and CO determined by self-gated UTE were identical to the values measured with self-gated FLASH and showed good agreement to the results obtained by echocardiography. Self-gated UTE allows for robust measurement of cardiac parameters of diagnostic interest. Image quality is superior to self-gated FLASH, rendering the method a powerful alternative for the assessment of cardiac function at high magnetic fields.

  20. Silicon nanotube field effect transistor with core-shell gate stacks for enhanced high-performance operation and area scaling benefits

    KAUST Repository

    Fahad, Hossain M.

    2011-10-12

    We introduce the concept of a silicon nanotube field effect transistor whose unique core-shell gate stacks help achieve full volume inversion by giving a surge in minority carrier concentration in the near vicinity of the ultrathin channel and at the same time rapid roll-off at the source and drain junctions constituting velocity saturation-induced higher drive current-enhanced high performance per device with efficient real estate consumption. The core-shell gate stacks also provide superior short channel effects control than classical planar metal oxide semiconductor field effect transistor (MOSFET) and gate-all-around nanowire FET. The proposed device offers the true potential to be an ideal blend for quantum ballistic transport study of device property control by bottom-up approach and high-density integration compatibility using top-down state-of-the-art complementary metal oxide semiconductor flow. © 2011 American Chemical Society.

  1. Gate-tunable high mobility remote-doped InSb/In{sub 1−x}Al{sub x}Sb quantum well heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Wei, E-mail: wyi@hrl.com, E-mail: MSokolich@hrl.com; Kiselev, Andrey A.; Thorp, Jacob; Noah, Ramsey; Nguyen, Binh-Minh; Bui, Steven; Rajavel, Rajesh D.; Hussain, Tahir; Gyure, Mark F.; Sokolich, Marko, E-mail: wyi@hrl.com, E-mail: MSokolich@hrl.com [HRL Laboratories, 3011 Malibu Canyon Rd, Malibu, California 90265 (United States); Kratz, Philip [Department of Applied Physics, Stanford University, Stanford, California 94305 (United States); Qian, Qi; Manfra, Michael J. [Department of Physics and Astronomy, Purdue University, 525 Northwestern Ave., West Lafayette, Indiana 47907 (United States); Pribiag, Vlad S.; Kouwenhoven, Leo P. [Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft (Netherlands); Marcus, Charles M. [Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen (Denmark)

    2015-04-06

    Gate-tunable high-mobility InSb/In{sub 1−x}Al{sub x}Sb quantum wells (QWs) grown on GaAs substrates are reported. The QW two-dimensional electron gas (2DEG) channel mobility in excess of 200 000 cm{sup 2}/V s is measured at T = 1.8 K. In asymmetrically remote-doped samples with an HfO{sub 2} gate dielectric formed by atomic layer deposition, parallel conduction is eliminated and complete 2DEG channel depletion is reached with minimal hysteresis in gate bias response of the 2DEG electron density. The integer quantum Hall effect with Landau level filling factor down to 1 is observed. A high-transparency non-alloyed Ohmic contact to the 2DEG with contact resistance below 1 Ω·mm is achieved at 1.8 K.

  2. Solution-based formation of high-quality gate dielectrics on epitaxial graphene by microwave-assisted annealing

    Science.gov (United States)

    Kim, Kwan-Soo; Park, Goon-Ho; Fukidome, Hirokazu; Suemitsu, Tetsuya; Otsuji, Taiichi; Cho, Won-Ju; Suemitsu, Maki

    2017-06-01

    We propose a damage-free formation method for high-quality gate dielectrics on epitaxial graphene (EG), which involves solution-based Al2O3 coating combined with microwave-assisted annealing (MW-sol-Al2O3). This method substantially preserves the pristine properties of EG with minimized hole doping and strain induction. The MW-sol-Al2O3 showed a surface roughness of ˜0.237 nm and a dielectric constant of 7.5. A leakage current of 8.7 × 10-6 A/cm2, which is 3 orders of magnitude smaller than that of natural Al2O3 at the same electric field, was obtained. These excellent MW-sol-Al2O3 properties are ascribed to the effective elimination of hydroxyl- and carboxyl-related components from the film by microwave-assisted annealing.

  3. High Sensitivity pH Sensor Based on Porous Silicon (PSi) Extended Gate Field-Effect Transistor

    Science.gov (United States)

    Al-Hardan, Naif H.; Abdul Hamid, Muhammad Azmi; Ahmed, Naser M.; Jalar, Azman; Shamsudin, Roslinda; Othman, Norinsan Kamil; Kar Keng, Lim; Chiu, Weesiong; Al-Rawi, Hamzah N.

    2016-01-01

    In this study, porous silicon (PSi) was prepared and tested as an extended gate field-effect transistor (EGFET) for pH sensing. The prepared PSi has pore sizes in the range of 500 to 750 nm with a depth of approximately 42 µm. The results of testing PSi for hydrogen ion sensing in different pH buffer solutions reveal that the PSi has a sensitivity value of 66 mV/pH that is considered a super Nernstian value. The sensor considers stability to be in the pH range of 2 to 12. The hysteresis values of the prepared PSi sensor were approximately 8.2 and 10.5 mV in the low and high pH loop, respectively. The result of this study reveals a promising application of PSi in the field for detecting hydrogen ions in different solutions. PMID:27338381

  4. Highly compact and accurate circuit-level macro modeling of gate-all-around charge-trap flash memory

    Science.gov (United States)

    Kim, Seunghyun; Lee, Sang-Ho; Kim, Young-Goan; Cho, Seongjae; Park, Byung-Gook

    2017-01-01

    In this paper, a highly reliable circuit model of gate-all-around (GAA) charge-trap flash (CTF) memory cell is proposed, considering the transient behaviors for describing the program operations with improved accuracy. Although several compact models have been reported in the previous literature, time-dependent behaviors have not been precisely reflected and the failures tend to get worse as the operation time elapses. Furthermore, the developed SPICE models in this work have been verified by the measurement results of the fabricated flash memory cells having silicon-oxide-nitride-oxide-silicon (SONOS). This more realistic model would be beneficial in designing the system architectures and setting up the operation schemes for the leading three-dimensional (3D) stack CTF memory.

  5. A modified golden gate attenuated total reflection (ATR) cell for monitoring phase transitions in multicomponent fluids at high temperatures.

    Science.gov (United States)

    Novitskiy, Alexander A; Ke, Jie; Comak, Gurbuz; Poliakoff, Martyn; George, Michael W

    2011-08-01

    A new continuous flow method using attenuated total reflection infrared (ATR-IR) spectroscopy has been developed for monitoring phase transitions in multicomponent fluids at high pressures and temperatures. Our approach uses Fourier transform infrared (FT-IR) and a modified Golden Gate attenuated total reflection (ATR) cell and exploits the fact that the absorbance of a vapor is much lower than that of the corresponding liquid to monitor the phase transition between vapor and liquid. We demonstrate that this method can provide quantitative measurements on both the dew point and the bubble point. We have validated our approach using three single-component systems (EtOH, MeOH, and H(2)O) and a binary system of EtOH + H(2)O, monitoring phase transitions at temperature up to 300 °C and pressure up to 10 MPa.

  6. Note: A high-frequency signal generator based on direct digital synthesizer and field-programmable gate array

    Science.gov (United States)

    Du, Yuanbo; Li, Wenbing; Ge, Yapeng; Li, Hui; Deng, Ke; Lu, Zehuang

    2017-09-01

    A high-frequency signal generator based on direct digital synthesizer (DDS) and field-programmable gate array (FPGA) is presented. The FPGA provides the controlling time sequence for the DDS, which has a highest output frequency of 1.4 GHz and a frequency resolution of 190 pHz. At an output frequency of 1.2 GHz, the measured phase noise, including the contribution of the reference clock, is -65 dBc/Hz@1 Hz, while the intrinsic phase noise is -82 dBc/Hz@1 Hz. Time delay of the DDS is measured to be less than 150 ns. The signal generator is used to drive an acousto-optic modulator, and the rise time due to the whole link is 24 ns. The developed signal generator can be used in many precision measurement experiments in the fields of atomic, molecular, and optical physics.

  7. Gate-all-around OTA`s for rad-hard and high-temperature analog applications

    Energy Technology Data Exchange (ETDEWEB)

    Vandooren, A.; Colinge, J.P. [Univ. of California, Davis, CA (United States). Dept. of Electrical and Computer Engineering; Flandre, D. [Univ. Catholique de Louvain, Louvain-La-Neuve (Belgium). Lab. de Microelectronique

    1999-08-01

    Performance of operational transconductance amplifiers (OTA`s) fabricated in the gate-all-around SOI technology is described at elevated temperature and after total dose irradiation. Design guidelines using two analog parameters (early voltage and transconductance to drain current ratio) are proposed for correct operation in these two different harsh environments. The design methodology using the two analog parameters of interest is proposed and applied to the specific case of the GAA technology. The temperature and dose dependence of the two above design parameters are then presented. Two different OTA architectures are considered: a single-stage amplifier and a folded cascode amplifier. Experimental results obtained separately for each environment are discussed. High-temperature measurements were performed up to 300 C, while total dose measurements were obtained for doses up to 15 Mrad(Si) total dose of gamma rays from a {sup 60}Co source.

  8. Implementation of a high resolution (< 11 ps RMS) Time-to-Digital Converter in a Field Programmable Gate Array

    Energy Technology Data Exchange (ETDEWEB)

    Ugur, Cahit [Helmholtz-Institut Mainz, Johannes Gutenberg-Universitaet Mainz (Germany); Bayer, Eugen [Department for Digital Electronics, University Kassel (Germany); Kurz, Nikolaus; Traxler, Michael [GSI Helmholtz Centre for Heavy Ion Research, Darmstadt (Germany); Michel, Jan [Institute for Nuclear Physics, Goethe University Frankfurt, Frankfurt am Main (Germany)

    2012-07-01

    A high resolution time-to-digital converter (TDC) was implemented in a general purpose field-programmable gate array (FPGA), a re-programmable digital chip. RMS and the time resolution of different channels are calculated for one clock cycle (5 ns) interval and a minimum of 10.3 ps RMS on two channels is achieved, which yields to a time resolution of 7.3 ps (10.3 ps/{radical}(2)) on a single channel. The TDC can be used in time-of-flight, time-over-threshold, drift time measurement applications as well as many other measurements with specific Front-End Electronics (FEE), e.g. charge measurements with charge-to-width (Q2W) FEE. The re-programmable flexibility of FPGAs also allows to have application specific features, e.g. trigger window, zero dead time etc.

  9. High Sensitivity pH Sensor Based on Porous Silicon (PSi Extended Gate Field-Effect Transistor

    Directory of Open Access Journals (Sweden)

    Naif H. Al-Hardan

    2016-06-01

    Full Text Available In this study, porous silicon (PSi was prepared and tested as an extended gate field-effect transistor (EGFET for pH sensing. The prepared PSi has pore sizes in the range of 500 to 750 nm with a depth of approximately 42 µm. The results of testing PSi for hydrogen ion sensing in different pH buffer solutions reveal that the PSi has a sensitivity value of 66 mV/pH that is considered a super Nernstian value. The sensor considers stability to be in the pH range of 2 to 12. The hysteresis values of the prepared PSi sensor were approximately 8.2 and 10.5 mV in the low and high pH loop, respectively. The result of this study reveals a promising application of PSi in the field for detecting hydrogen ions in different solutions.

  10. Low-temperature formation of high-quality gate oxide by ultraviolet irradiation on spin-on-glass

    Science.gov (United States)

    Usuda, R.; Uchida, K.; Nozaki, S.

    2015-11-01

    Although a UV cure was found to effectively convert a perhydropolysilazane (PHPS) spin-on-glass film into a dense SiOx film at low temperature, the electrical characteristics were never reported in order to recommend the use of PHPS as a gate-oxide material that can be formed at low temperature. We have formed a high-quality gate oxide by UV irradiation on the PHPS film, and obtained an interface midgap trap density of 3.4 × 1011 cm-2 eV-1 by the UV wet oxidation and UV post-metallization annealing (PMA), at a temperature as low as 160 °C. In contrast to the UV irradiation using short-wavelength UV light, which is well known to enhance oxidation by the production of the excited states of oxygen, the UV irradiation was carried out using longer-wavelength UV light from a metal halide lamp. The UV irradiation during the wet oxidation of the PHPS film generates electron-hole pairs. The electrons ionize the H2O molecules and facilitate dissociation of the molecules into H and OH-. The OH- ions are highly reactive with Si and improve the stoichiometry of the oxide. The UV irradiation during the PMA excites the electrons from the accumulation layer, and the built-in electric field makes the electron injection into the oxide much easier. The electrons injected into the oxide recombine with the trapped holes, which have caused a large negative flat band voltage shift after the UV wet oxidation, and also ionize the H2O molecules. The ionization results in the electron stimulated dissociation of H2O molecules and the decreased interface trap density.

  11. Dual Metal/High-k Gate-Last Complementary Metal-Oxide-Semiconductor Field-Effect Transistor with SiBN Film and Characteristic Behavior In Sub-1-nm Equivalent Oxide Thickness

    Science.gov (United States)

    Kikuchi, Yoshiaki; Wakabayashi, Hitoshi; Tsukamoto, Masanori; Nagashima, Naoki

    2011-08-01

    For the first time, dual metal/high-k gate-last complementary metal-oxide-semiconductor field-effect transistors (CMOSFETs) with low-dielectric-constant-material offset spacers and several gate oxide thicknesses were fabricated to improve CMOSFETs characteristics. Improvements of 23 aF/µm in parasitic capacitances were confirmed with a low-dielectric-constant material, and drive current improvements were also achieved with a thin gate oxide. The drive currents at 100 nA/µm off leakages in n-type metal-oxide-semiconductor (NMOS) were improved from 830 to 950 µA/µm and that in p-type metal-oxide-semiconductor (PMOS) were from 405 to 450 µA/µm with a reduction in gate oxide thickness. The thin gate oxide in PMOS was thinner than that in NMOS and the gate leakage was increased. However the gate leakage did not affect the off leakage below a gate length of about 44 nm. On the basis of this result, in these gate-last CMOSFETs, it is concluded that the transistors have potential for further reduction of the equivalent oxide thickness without an increase in off leakages at short gate lengths for high off leakage CMOSFETs. For low off leakage CMOSFETs, the optimization of wet process condition is needed to prevent the reduction of the 2 nm HfO2 thickness in PMOS during a wet process.

  12. Electrical properties of Ge metal-oxide-semiconductor capacitors with high-k La2O3 gate dielectric incorporated by N or/and Ti

    Science.gov (United States)

    Huoxi, Xu; Jingping, Xu

    2016-06-01

    LaON, LaTiO and LaTiON films are deposited as gate dielectrics by incorporating N or/and Ti into La2O3 using the sputtering method to fabricate Ge MOS capacitors, and the electrical properties of the devices are carefully examined. LaON/Ge capacitors exhibit the best interface quality, gate leakage property and device reliability, but a smaller k value (14.9). LaTiO/Ge capacitors exhibit a higher k value (22.7), but a deteriorated interface quality, gate leakage property and device reliability. LaTiON/Ge capacitors exhibit the highest k value (24.6), and a relatively better interface quality (3.1 × 1011 eV-1 cm-2), gate leakage property (3.6 × 10-3 A/cm2 at V g = 1 V + V fb) and device reliability. Therefore, LaTiON is more suitable for high performance Ge MOS devices as a gate dielectric than LaON and LaTiO materials. Project supported by the National Natural Science Foundation of China (No. 61274112), the Natural Science Foundation of Hubei Province (No. 2011CDB165), and the Scientific Research Program of Huanggang Normal University (No. 2012028803).

  13. Highly-efficient gating of solid-state nanochannels by DNA supersandwich structure containing ATP aptamers: a nanofluidic IMPLICATION logic device.

    Science.gov (United States)

    Jiang, Yanan; Liu, Nannan; Guo, Wei; Xia, Fan; Jiang, Lei

    2012-09-19

    Integrating biological components into artificial devices establishes an interface to understand and imitate the superior functionalities of the living systems. One challenge in developing biohybrid nanosystems mimicking the gating function of the biological ion channels is to enhance the gating efficiency of the man-made systems. Herein, we demonstrate a DNA supersandwich and ATP gated nanofluidic device that exhibits high ON-OFF ratios (up to 10(6)) and a perfect electric seal at its closed state (~GΩ). The ON-OFF ratio is distinctly higher than existing chemically modified nanofluidic gating systems. The gigaohm seal is comparable with that required in ion channel electrophysiological recording and some lipid bilayer-coated nanopore sensors. The gating function is implemented by self-assembling DNA supersandwich structures into solid-state nanochannels (open-to-closed) and their disassembly through ATP-DNA binding interactions (closed-to-open). On the basis of the reversible and all-or-none electrochemical switching properties, we further achieve the IMPLICATION logic operations within the nanofluidic structures. The present biohybrid nanofluidic device translates molecular events into electrical signals and indicates a built-in signal amplification mechanism for future nanofluidic biosensing and modular DNA computing on solid-state substrates.

  14. High sensitivity AlGaN/GaN field effect transistor protein sensors operated in the subthreshold regime by a control gate electrode

    Science.gov (United States)

    Wen, Xuejin; Gupta, Samit; Wang, Yuji; Nicholson, Theodore R.; Lee, Stephen C.; Lu, Wu

    2011-07-01

    We demonstrate high sensitivity AlGaN/GaN field effect transistor biosensors with a control gate electrode for streptavidin detection. The device active area is functionalized with 3-Aminopropyltriethoxysilane and N-hydroxysulfosuccinimide-biotin for streptavidin binding. Without any electrochemical side effects, a gate voltage is applied through a Pt control electrode to the solution so that the device operates sensitively in the subthreshold regime. Due to the logarithmic relationship between the channel current and gate voltage in the subthreshold regime, at a concentration of 4.73 pM streptavidin, the device exhibits 9.97% current change in the subthreshold regime compared with the current in phosphate buffered saline solution. In the linear regime, the current change is 0.49% at the same streptavidin concentration.

  15. Current collapse imaging of Schottky gate AlGaN/GaN high electron mobility transistors by electric field-induced optical second-harmonic generation measurement

    Energy Technology Data Exchange (ETDEWEB)

    Katsuno, Takashi, E-mail: e1417@mosk.tytlabs.co.jp; Ishikawa, Tsuyoshi; Ueda, Hiroyuki; Uesugi, Tsutomu [Toyota Central R and D Laboratories Inc., Nagakute, Aichi 480-1192 (Japan); Manaka, Takaaki; Iwamoto, Mitsumasa [Department of Physical Electronics, Tokyo Institute of Technology, Meguro, Tokyo 152-8552 (Japan)

    2014-06-23

    Two-dimensional current collapse imaging of a Schottky gate AlGaN/GaN high electron mobility transistor device was achieved by optical electric field-induced second-harmonic generation (EFISHG) measurements. EFISHG measurements can detect the electric field produced by carriers trapped in the on-state of the device, which leads to current collapse. Immediately after (e.g., 1, 100, or 800 μs) the completion of drain-stress voltage (200 V) in the off-state, the second-harmonic (SH) signals appeared within 2 μm from the gate edge on the drain electrode. The SH signal intensity became weak with time, which suggests that the trapped carriers are emitted from the trap sites. The SH signal location supports the well-known virtual gate model for current collapse.

  16. Ballistic Imaging of High-Pressure Fuel Sprays using Incoherent, Ultra- short Pulsed Illumination with an Ultrafast OKE-based Time Gating

    CERN Document Server

    Purwar, Harsh; Rozé, Claude; Blaisot, Jean-Bernard

    2015-01-01

    We present an optical Kerr effect based time-gate with the collinear incidence of the pump and probe beams at the Kerr medium, liquid carbon disulfide, for ballistic imaging of the high-pressure fuel sprays. The probe pulse used to illuminate the object under study is extracted from the supercontinuum generated by tightly focusing intense femtosecond laser pulses inside water, thereby destroying their coherence. The optical imaging spatial resolution and gate timings are investigated and compared with a similar setup without supercontinuum generation, where the probe is still coherent. And finally, a few ballistic images of the fuel sprays using coherent and incoherent illumination with the proposed time-gate are presented and compared qualitatively.

  17. Highly scaled ( Lg ˜ 56 nm) gate-last Si tunnel field-effect transistors with ION > 100 μA/μm

    Science.gov (United States)

    Loh, Wei-Yip; Jeon, Kanghoon; Kang, Chang Yong; Oh, Jungwoo; King Liu, Tsu-Jae; Tseng, Hsing-Huang; Xiong, Wade; Majhi, Prashant; Jammy, Raj; Hu, Chenming

    2011-11-01

    Planar band-to-band tunneling FETs (TFETs) have been fabricated on silicon-on-insulator (SOI) substrates using conventional CMOS technologies with a highly scaled sub-60 nm gate length (effective gate length [Lg] ∼ 40 nm due to an overlap between the source and gate) and different anneal sequences. The optimal anneal sequence including spike and flash annealing resulted in a drive ON current (ION)) > 100 μA/μm with ION/IOFF > 105 at a drain bias of -1 V. The devices exhibited negative differential resistance and non-linear subthreshold temperature dependencies, consistent with the band-to-band tunneling mechanism. Simulations using a 2-D TCAD simulator, MEDICI, agreed with experimental data, demonstrating the possibility of Si tunnel transistors in logic applications.

  18. Characterization, integration and reliability of HfO{sub 2} and LaLuO{sub 3} high-κ/metal gate stacks for CMOS applications

    Energy Technology Data Exchange (ETDEWEB)

    Nichau, Alexander

    2013-07-15

    The continued downscaling of MOSFET dimensions requires an equivalent oxide thickness (EOT) of the gate stack below 1 nm. An EOT below 1.4 nm is hereby enabled by the use of high-κ/metal gate stacks. LaLuO{sub 3} and HfO{sub 2} are investigated as two different high-κ oxides on silicon in conjunction with TiN as the metal electrode. LaLuO{sub 3} and its temperature-dependent silicate formation are characterized by hard X-ray photoemission spectroscopy (HAXPES). The effective attenuation length of LaLuO{sub 3} is determined between 7 and 13 keV to enable future interface and diffusion studies. In a first investigation of LaLuO{sub 3} on germanium, germanate formation is shown. LaLuO{sub 3} is further integrated in a high-temperature MOSFET process flow with varying thermal treatment. The devices feature drive currents up to 70μA/μm at 1μm gate length. Several optimization steps are presented. The effective device mobility is related to silicate formation and thermal budget. At high temperature the silicate formation leads to mobility degradation due to La-rich silicate formation. The integration of LaLuO{sub 3} in high-T processes delicately connects with the optimization of the TiN metal electrode. Hereby, stoichiometric TiN yields the best results in terms of thermal stability with respect to Si-capping and high-κ oxide. Different approaches are presented for a further EOT reduction with LaLuO{sub 3} and HfO{sub 2}. Thereby the thermodynamic and kinetic predictions are employed to estimate the behavior on the nanoscale. Based on thermodynamics, excess oxygen in the gate stack, especially in oxidized metal electrodes, is identified to prevent EOT scaling below 1.2 nm. The equivalent oxide thickness of HfO{sub 2} gate stacks is scalable below 1 nm by the use of thinned interfacial SiO{sub 2}. The prevention of oxygen incorporation into the metal electrode by Si-capping maintains the EOT after high temperature annealing. Redox systems are employed within the

  19. A FPGA Implementation of JPEG Baseline Encoder for Wearable Devices.

    Science.gov (United States)

    Li, Yuecheng; Jia, Wenyan; Luan, Bo; Mao, Zhi-Hong; Zhang, Hong; Sun, Mingui

    2015-04-01

    In this paper, an efficient field-programmable gate array (FPGA) implementation of the JPEG baseline image compression encoder is presented for wearable devices in health and wellness applications. In order to gain flexibility in developing FPGA-specific software and balance between real-time performance and resources utilization, A High Level Synthesis (HLS) tool is utilized in our system design. An optimized dataflow configuration with a padding scheme simplifies the timing control for data transfer. Our experiments with a system-on-chip multi-sensor system have verified our FPGA implementation with respect to real-time performance, computational efficiency, and FPGA resource utilization.

  20. Electro-Thermo-Mechanical Analysis of High-Power Press-Pack Insulated Gate Bipolar Transistors under Various Mechanical Clamping Conditions

    DEFF Research Database (Denmark)

    Hasmasan, Adrian Augustin; Busca, Cristian; Teodorescu, Remus;

    2014-01-01

    production. The reliability of the components has a large impact on the overall cost of a WT, and press-pack (PP) insulated gate bipolar transistors (IGBTs) could be a good solution for future multi-megawatt WTs because of advantages like high power density and reliability. When used in power converters, PP...

  1. High performance TiN gate contact on AlGaN/GaN transistor using a mechanically strain induced P-doping

    Energy Technology Data Exchange (ETDEWEB)

    Soltani, A., E-mail: ali.soltani@iemn.univ-lille1.fr; Rousseau, M.; Gerbedoen, J.-C.; Bourzgui, N. [Institut d' Electronique de Microélectronique et de Nanotechnologie, UMR-CNRS 8520, USTL, Avenue Poincaré, 59652 Villeneuve d' Ascq (France); Mattalah, M. [Laboratoire de Microélectronique, Université Djilali Liabès, 22000 Sidi Bel Abbès (Algeria); Bonanno, P. L.; Ougazzaden, A. [School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30324-0250 (United States); UMI 2958 Georgia Tech-CNRS, Georgia Tech Lorraine, 2-3 Rue Marconi, 57070 Metz-Technopôle (France); Telia, A. [LMI, Electronic Department, Faculty of Engineering, Mentouri University of Constantine, Constantine (Algeria); Patriarche, G. [Laboratoire de Photonique et Nanostructures, CNRS UPR 20, Route de Nozay, 91460 Marcoussis (France); BenMoussa, A. [Solar Terrestrial Center of Excellence, Royal Observatory of Belgium, Circular 3, B-1180 Brussels (Belgium)

    2014-06-09

    High performance titanium nitride sub-100 nm rectifying contact, deposited by sputtering on AlGaN/GaN high electron mobility transistors, shows a reverse leakage current as low as 38 pA/mm at V{sub GS} = −40 V and a Schottky barrier height of 0.95 eV. Based on structural characterization and 3D simulations, it is found that the polarization gradient induced by the gate metallization forms a P-type pseudo-doping region under the gate between the tensile surface and the compressively strained bulk AlGaN barrier layer. The strain induced by the gate metallization can compensate for the piezoelectric component. As a result, the gate contact can operate at temperatures as high as 700 °C and can withstand a large reverse bias of up to −100 V, which is interesting for high-performance transistors dedicated to power applications.

  2. Approaches of Bill & Melinda Gates Foundation-Funded Intermediary Organizations to Structuring and Supporting Small High Schools in New York City. Executive Summary

    Science.gov (United States)

    Foley, Eileen

    2010-01-01

    In 2003, a few years after the Bill & Melinda Gates Foundation began implementing its small schools reform agenda, the Chancellor of the New York City Department of Education (DOE) announced a plan to replace large failing high schools in New York City with 200 small schools. In short order, the foundation and the Chancellor became partners with…

  3. A nanomechanical Fredkin gate.

    Science.gov (United States)

    Wenzler, Josef-Stefan; Dunn, Tyler; Toffoli, Tommaso; Mohanty, Pritiraj

    2014-01-08

    Irreversible logic operations inevitably discard information, setting fundamental limitations on the flexibility and the efficiency of modern computation. To circumvent the limit imposed by the von Neumann-Landauer (VNL) principle, an important objective is the development of reversible logic gates, as proposed by Fredkin, Toffoli, Wilczek, Feynman, and others. Here, we present a novel nanomechanical logic architecture for implementing a Fredkin gate, a universal logic gate from which any reversible computation can be built. In addition to verifying the truth table, we demonstrate operation of the device as an AND, OR, NOT, and FANOUT gate. Excluding losses due to resonator dissipation and transduction, which will require significant improvement in order to minimize the overall energy cost, our device requires an energy of order 10(4) kT per logic operation, similar in magnitude to state-of-the-art transistor-based technologies. Ultimately, reversible nanomechanical logic gates could play a crucial role in developing highly efficient reversible computers, with implications for efficient error correction and quantum computing.

  4. Theory and implementation of a very high throughput true random number generator in field programmable gate array.

    Science.gov (United States)

    Wang, Yonggang; Hui, Cong; Liu, Chong; Xu, Chao

    2016-04-01

    The contribution of this paper is proposing a new entropy extraction mechanism based on sampling phase jitter in ring oscillators to make a high throughput true random number generator in a field programmable gate array (FPGA) practical. Starting from experimental observation and analysis of the entropy source in FPGA, a multi-phase sampling method is exploited to harvest the clock jitter with a maximum entropy and fast sampling speed. This parametrized design is implemented in a Xilinx Artix-7 FPGA, where the carry chains in the FPGA are explored to realize the precise phase shifting. The generator circuit is simple and resource-saving, so that multiple generation channels can run in parallel to scale the output throughput for specific applications. The prototype integrates 64 circuit units in the FPGA to provide a total output throughput of 7.68 Gbps, which meets the requirement of current high-speed quantum key distribution systems. The randomness evaluation, as well as its robustness to ambient temperature, confirms that the new method in a purely digital fashion can provide high-speed high-quality random bit sequences for a variety of embedded applications.

  5. Theory and implementation of a very high throughput true random number generator in field programmable gate array

    Science.gov (United States)

    Wang, Yonggang; Hui, Cong; Liu, Chong; Xu, Chao

    2016-04-01

    The contribution of this paper is proposing a new entropy extraction mechanism based on sampling phase jitter in ring oscillators to make a high throughput true random number generator in a field programmable gate array (FPGA) practical. Starting from experimental observation and analysis of the entropy source in FPGA, a multi-phase sampling method is exploited to harvest the clock jitter with a maximum entropy and fast sampling speed. This parametrized design is implemented in a Xilinx Artix-7 FPGA, where the carry chains in the FPGA are explored to realize the precise phase shifting. The generator circuit is simple and resource-saving, so that multiple generation channels can run in parallel to scale the output throughput for specific applications. The prototype integrates 64 circuit units in the FPGA to provide a total output throughput of 7.68 Gbps, which meets the requirement of current high-speed quantum key distribution systems. The randomness evaluation, as well as its robustness to ambient temperature, confirms that the new method in a purely digital fashion can provide high-speed high-quality random bit sequences for a variety of embedded applications.

  6. Investigation of gate-diode degradation in normally-off p-GaN/AlGaN/GaN high-electron-mobility transistors

    Energy Technology Data Exchange (ETDEWEB)

    Ťapajna, M., E-mail: milan.tapajna@savba.sk; Kuzmík, J. [Institute of Electrical Engineering, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava (Slovakia); Hilt, O.; Bahat-Treidel, E.; Würfl, J. [Ferdinand-Braun-Institut, Leibniz Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Strasse 4, 12489 Berlin (Germany)

    2015-11-09

    Gate diode conduction mechanisms were analyzed in normally-off p-GaN/AlGaN/GaN high-electron mobility transistors grown on Si wafers before and after forward bias stresses. Electrical characterization of the gate diodes indicates forward current to be limited by channel electrons injected through the AlGaN/p-GaN triangular barrier promoted by traps. On the other hand, reverse current was found to be consistent with carrier generation-recombination processes in the AlGaN layer. Soft breakdown observed after ∼10{sup 5 }s during forward bias stress at gate voltage of 7 V was attributed to formation of conductive channel in p-GaN/AlGaN gate stack via trap generation and percolation mechanism, likely due to coexistence of high electric field and high forward current density. Possible enhancement of localized conductive channels originating from spatial inhomogeneities is proposed to be responsible for the degradation.

  7. Anisotropic high-k deposition for gate-last processing of metal-oxide-semiconductor field-effect transistor utilizing electron-cyclotron-resonance plasma sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Yoshiaki, E-mail: kikuchi.y.ao@m.titech.ac.jp; Gao, Jun; Sano, Takahiro; Ohmi, Shun-ichiro, E-mail: ohmi@ep.titech.ac.jp

    2012-01-31

    A high-k/metal gate structure has been investigated for application to state-of-the-art metal-oxide-semiconductor field-effect transistors. In the high-k/metal gate structure, the 32-nm technology node was realized by using the high-k-last, metal-last integration process. We investigated anisotropic deposition for 3-dimensional gate structures on Si substrates utilizing electron-cyclotron-resonance plasma sputtering to reduce parasitic capacitance. Anisotropic HfN film deposition was realized and the deposition thickness on the side wall was reduced with decreasing sputtering gas pressure, from 0.15 to 0.06 Pa, corresponding to Ar/N{sub 2} flow ratios of 20/1 and 5/1 sccm. The HfSiON gate insulator formed from the anisotropically deposited HfN film showed an equivalent-oxide-thickness of 2.1 nm and a gate leakage of 3.1 Multiplication-Sign 10{sup -6}A/cm{sup 2} at V{sub FB}-1.0. - Highlights: Black-Right-Pointing-Pointer High-k film deposition was controlled by the deposition pressure. Black-Right-Pointing-Pointer The pressure decreases with a reduction of gas flow rate during the high-k film deposition. Black-Right-Pointing-Pointer A flat band voltage shows negative shifts with reduction of gas flow rates. Black-Right-Pointing-Pointer A reason of the flat band voltage shift is an increase in Si-N bonding.

  8. Graphene quantum dots as a highly efficient solution-processed charge trapping medium for organic nano-floating gate memory.

    Science.gov (United States)

    Ji, Yongsung; Kim, Juhan; Cha, An-Na; Lee, Sang-A; Lee, Myung Woo; Suh, Jung Sang; Bae, Sukang; Moon, Byung Joon; Lee, Sang Hyun; Lee, Dong Su; Wang, Gunuk; Kim, Tae-Wook

    2016-04-08

    A highly efficient solution-processible charge trapping medium is a prerequisite to developing high-performance organic nano-floating gate memory (NFGM) devices. Although several candidates for the charge trapping layer have been proposed for organic memory, a method for significantly increasing the density of stored charges in nanoscale layers remains a considerable challenge. Here, solution-processible graphene quantum dots (GQDs) were prepared by a modified thermal plasma jet method; the GQDs were mostly composed of carbon without any serious oxidation, which was confirmed by x-ray photoelectron spectroscopy. These GQDs have multiple energy levels because of their size distribution, and they can be effectively utilized as charge trapping media for organic NFGM applications. The NFGM device exhibited excellent reversible switching characteristics, with an on/off current ratio greater than 10(6), a stable retention time of 10(4) s and reliable cycling endurance over 100 cycles. In particular, we estimated that the GQDs layer trapped ∼7.2 × 10(12) cm(-2) charges per unit area, which is a much higher density than those of other solution-processible nanomaterials, suggesting that the GQDs layer holds promise as a highly efficient nanoscale charge trapping material.

  9. Ankylosing Spondylitis Patients Commencing Biologic Therapy Have High Baseline Levels of Comorbidity: A Report from the Australian Rheumatology Association Database

    Science.gov (United States)

    Oldroyd, John; Schachna, Lionel; Buchbinder, Rachelle; Staples, Margaret; Murphy, Bridie; Bond, Molly; Briggs, Andrew; Lassere, Marissa; March, Lyn

    2009-01-01

    Aims. To compare the baseline characteristics of a population-based cohort of patients with ankylosing spondylitis (AS) commencing biological therapy to the reported characteristics of bDMARD randomised controlled trials (RCTs) participants. Methods. Descriptive analysis of AS participants in the Australian Rheumatology Association Database (ARAD) who were commencing bDMARD therapy. Results. Up to December 2008, 389 patients with AS were enrolled in ARAD. 354 (91.0%) had taken bDMARDs at some time, and 198 (55.9%) completed their entry questionnaire prior to or within 6 months of commencing bDMARDs. 131 (66.1%) had at least one comorbid condition, and 24 (6.8%) had a previous malignancy (15 nonmelanoma skin, 4 melanoma, 2 prostate, 1 breast, cervix, and bowel). Compared with RCT participants, ARAD participants were older, had longer disease duration and higher baseline disease activity. Conclusions. AS patients commencing bDMARDs in routine care are significantly different to RCT participants and have significant baseline comorbidities. PMID:20107564

  10. A Numerical Technique for Removing Residual Gate-Source Capacitances When Extracting Parasitic Inductance for GaN High Electron Mobility Transistors (HEMTs)

    Science.gov (United States)

    2011-03-01

    Residual Gate-source Capacitances When Extracting Parasitic Inductance for GaN High Electron Mobility Transistors ( HEMTs ) Benjamin Huebschman and Pankaj...Extracting Parasitic Inductance for GaN High Electron Mobility Transistors ( HEMTs ) 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...nitride ( GaN ) high electron mobility transistors ( HEMTs ) begin to realize their performance potential, and to transition from experimental devices to

  11. The upgraded PTB 600 m baseline: a high-accuracy reference for the calibration and the development of long distance measurement devices

    Science.gov (United States)

    Pollinger, Florian; Meyer, Tobias; Beyer, Jens; Doloca, Nicolae R.; Schellin, Wolfgang; Niemeier, Wolfgang; Jokela, Jorma; Häkli, Pasi; Abou-Zeid, Ahmed; Meiners-Hagen, Karl

    2012-09-01

    The calibration and verification of high-precision electronic distance meters (EDMs) requires well-characterized and calibrated geodetic baselines. As the length measurements are performed typically over several hundred metres in air, a thorough understanding of the environmental conditions is necessary. In the course of a major refurbishment, the 600 m baseline of the Physikalisch-Technische Bundesanstalt at Braunschweig, Germany, was equipped with a dense environmental sensor network. This paper presents the characterization of this novel reference baseline, including the calibration of the inter-pillar distances, and identifies the major sources of uncertainty for such a length standard. A preliminary expanded standard uncertainty (k = 2) of U ( l ) _{k=2}=\\sqrt{( 6.2 \\times 10^{-4} \\: m )^2 + ( 7.6 \\times 10^{-7} \\, l )^2} is deduced for single-slope distance comparisons on the baseline. In the course of a full calibration, the additive constant cEDM of an EDM can currently be determined with an expanded uncertainty of U(cEDM)k = 2 = 6.1 × 10-5 m, and its scale correction sEDM with an expanded uncertainty of U(sEDM)k = 2 = 8.2 × 10-7. As an example, a femtosecond laser-based distance measurement over 600 m on this baseline is presented.

  12. Highly-accelerated self-gated free-breathing 3D cardiac cine MRI: validation in assessment of left ventricular function.

    Science.gov (United States)

    Liu, Jing; Feng, Li; Shen, Hsin-Wei; Zhu, Chengcheng; Wang, Yan; Mukai, Kanae; Brooks, Gabriel C; Ordovas, Karen; Saloner, David

    2017-08-01

    This work presents a highly-accelerated, self-gated, free-breathing 3D cardiac cine MRI method for cardiac function assessment. A golden-ratio profile based variable-density, pseudo-random, Cartesian undersampling scheme was implemented for continuous 3D data acquisition. Respiratory self-gating was achieved by deriving motion signal from the acquired MRI data. A multi-coil compressed sensing technique was employed to reconstruct 4D images (3D+time). 3D cardiac cine imaging with self-gating was compared to bellows gating and the clinical standard breath-held 2D cine imaging for evaluation of self-gating accuracy, image quality, and cardiac function in eight volunteers. Reproducibility of 3D imaging was assessed. Self-gated 3D imaging provided an image quality score of 3.4 ± 0.7 vs 4.0 ± 0 with the 2D method (p = 0.06). It determined left ventricular end-systolic volume as 42.4 ± 11.5 mL, end-diastolic volume as 111.1 ± 24.7 mL, and ejection fraction as 62.0 ± 3.1%, which were comparable to the 2D method, with bias ± 1.96 × SD of -0.8 ± 7.5 mL (p = 0.90), 2.6 ± 3.3 mL (p = 0.84) and 1.4 ± 6.4% (p = 0.45), respectively. The proposed 3D cardiac cine imaging method enables reliable respiratory self-gating performance with good reproducibility, and provides comparable image quality and functional measurements to 2D imaging, suggesting that self-gated, free-breathing 3D cardiac cine MRI framework is promising for improved patient comfort and cardiac MRI scan efficiency.

  13. The Theoretical Investigation and Analysis of High-Performance ZnO Double-Gate Double-Layer Insulator Thin-Film Transistors

    Institute of Scientific and Technical Information of China (English)

    GAO Hai-Xia; HU Rong; YANG Yin-Tang

    2012-01-01

    A novel structure of a ZnO thin-film transistor with a double-gate and double-layer insulator is proposed to improve device performance.Compared with the conventional ZnO thin-film transistor structure,the novel thinfilm transistor has a higher on-state current,steeper sub-threshold characteristics and a lower threshold voltage,owing to the double-gate and high-k dielectric.Based on two-dimensional simulation,the potential channel distribution and the reasons for the improvement in performance are investigated.%A novei structure of a ZnO thin-film transistor with a double-gate and double-layer insulator is proposed to improve device performance. Compared with the conventional ZnO thin-Rim transistor structure, the novel thin-Sim transistor has a higher on-state current, steeper sub-threshold characteristics and a lower threshold voltage, owing to the double-gate and high-k dielectric. Based on two-dimensional simulation, the potential channel distribution and the reasons for the improvement in performance are investigated.

  14. Suppression of surface-originated gate lag by a dual-channel AlN/GaN high electron mobility transistor architecture

    Science.gov (United States)

    Deen, David A.; Storm, David F.; Scott Katzer, D.; Bass, R.; Meyer, David J.

    2016-08-01

    A dual-channel AlN/GaN high electron mobility transistor (HEMT) architecture is demonstrated that leverages ultra-thin epitaxial layers to suppress surface-related gate lag. Two high-density two-dimensional electron gas (2DEG) channels are utilized in an AlN/GaN/AlN/GaN heterostructure wherein the top 2DEG serves as a quasi-equipotential that screens potential fluctuations resulting from distributed surface and interface states. The bottom channel serves as the transistor's modulated channel. Dual-channel AlN/GaN heterostructures were grown by molecular beam epitaxy on free-standing hydride vapor phase epitaxy GaN substrates. HEMTs fabricated with 300 nm long recessed gates demonstrated a gate lag ratio (GLR) of 0.88 with no degradation in drain current after bias stressed in subthreshold. These structures additionally achieved small signal metrics ft/fmax of 27/46 GHz. These performance results are contrasted with the non-recessed gate dual-channel HEMT with a GLR of 0.74 and 82 mA/mm current collapse with ft/fmax of 48/60 GHz.

  15. The thermal stability and electrical properties of LaErO{sub 3} films as high-k gate dielectrics

    Energy Technology Data Exchange (ETDEWEB)

    Gao Xu; Yin Jiang; Xia Yidong; Yin Kuibo; Gao Ligang; Guo Hongxuan; Liu Zhiguo [National Laboratory of Solid State Microstructure, Nanjing University, Nanjing 210093 (China)], E-mail: jyin@nju.edu.cn

    2008-12-07

    Lanthanum erbium oxide thin films have been deposited on an Si (1 0 0) wafer by using the pulsed laser deposition technique. The thermal and electrical properties of LaErO{sub 3} films were investigated by x-ray diffraction, x-ray photoelectron spectroscopy and high resolution transmission electron microscopy. Capacitance measurements reveal good C-V curves with an equivalent oxide thickness of 1.4 nm and little hysteresis. Transmission electron microscopic images reveal that the 6.5 nm LaErO{sub 3} film shows a thin interfacial layer even after being annealed in N{sub 2} at 700 deg. C for 30 s. X-ray photoelectron spectroscopic spectra indicate that little SiO{sub 2} was formed at the interface during the deposition of LaErO{sub 3} films. The measured thermal and electrical properties of the thin film suggest that the LaErO{sub 3} film should be a promising candidate for future high-k gate dielectrics.

  16. High-Threshold Low-Overhead Fault-Tolerant Classical Computation and the Replacement of Measurements with Unitary Quantum Gates

    Science.gov (United States)

    Cruikshank, Benjamin; Jacobs, Kurt

    2017-07-01

    von Neumann's classic "multiplexing" method is unique in achieving high-threshold fault-tolerant classical computation (FTCC), but has several significant barriers to implementation: (i) the extremely complex circuits required by randomized connections, (ii) the difficulty of calculating its performance in practical regimes of both code size and logical error rate, and (iii) the (perceived) need for large code sizes. Here we present numerical results indicating that the third assertion is false, and introduce a novel scheme that eliminates the two remaining problems while retaining a threshold very close to von Neumann's ideal of 1 /6 . We present a simple, highly ordered wiring structure that vastly reduces the circuit complexity, demonstrates that randomization is unnecessary, and provides a feasible method to calculate the performance. This in turn allows us to show that the scheme requires only moderate code sizes, vastly outperforms concatenation schemes, and under a standard error model a unitary implementation realizes universal FTCC with an accuracy threshold of p <5.5 %, in which p is the error probability for 3-qubit gates. FTCC is a key component in realizing measurement-free protocols for quantum information processing. In view of this, we use our scheme to show that all-unitary quantum circuits can reproduce any measurement-based feedback process in which the asymptotic error probabilities for the measurement and feedback are (32 /63 )p ≈0.51 p and 1.51 p , respectively.

  17. High Electron Mobility Ge n-Channel Metal-Insulator-Semiconductor Field-Effect Transistors Fabricated by the Gate-Last Process with the Solid Source Diffusion Technique

    Science.gov (United States)

    Maeda, Tatsuro; Morita, Yukinori; Takagi, Shinichi

    2010-06-01

    We fabricate high-k/Ge n-channel metal-insulator-semiconductor field-effect transistors (MISFETs) by the gate-last process with the thermal solid source diffusion to achieve both of high quality source/drain (S/D) and gate stack. The n+/p junction formed by solid source diffusion technique of Sb dopant shows the excellent diode characteristics of ˜1.5×105 on/off ratio between +1 and -1 V and the quite low reverse current density of ˜4.1×10-4 A/cm2 at +1 V after the fabrication of high-k/Ge n-channel MISFETs that enable us to observe well-behaved transistor performances. The extracted electron mobility with the peak of 891 cm2/(V.s) is high enough to be superior to the Si universal electron mobility especially in low Eeff.

  18. Increased Risk of Progression of Coronary Artery Calcification in Male Subjects with High Baseline Waist-to-Height Ratio: The Kangbuk Samsung Health Study.

    Science.gov (United States)

    Oh, Hyung Geun; Nallamshetty, Shriram; Rhee, Eun Jung

    2016-02-01

    The waist-to-height ratio (WHtR) is an easy and inexpensive adiposity index that reflects central obesity. In this study, we examined the association of baseline WHtR and progression of coronary artery calcification (CAC) over 4 years of follow-up in apparently healthy Korean men. A total of 1,048 male participants (mean age, 40.9 years) in a health-screening program in Kangbuk Samsung Hospital, Seoul, Korea who repeated a medical check-up in 2010 and 2014 were recruited. Baseline WHtR was calculated using the value for the waist in 2010 divided by the value for height in 2010. The CAC score (CACS) of each subject was measured by multi-detector computed tomography in both 2010 and 2014. Progression of CAC was defined as a CACS change over 4 years greater than 0. During the follow-up period, progression of CAC occurred in 278 subjects (26.5%). The subjects with CAC progression had slightly higher but significant baseline WHtR compared to those who did not show CAC progression (0.51±0.04 vs. 0.50±0.04, P<0.01). The proportion of subjects with CAC progression significantly increased as the baseline WHtR increased from the 1st quartile to 4th quartile groups (18.3%, 18.7%, 28.8%, and 34.2%; P<0.01). The risk for CAC progression was elevated with an odds ratio of 1.602 in the 4th quartile group of baseline WHtR even after adjustment for confounding variables (95% confidence interval, 1.040 to 2.466). Increased baseline WHtR was associated with increased risk for CAC progression. WHtR might be a useful screening tool to identify individuals at high risk for subclinical atherosclerosis.

  19. Influence of multi-deposition multi-annealing on time-dependent dielectric breakdown characteristics of PMOS with high-/metal gate last process

    Institute of Scientific and Technical Information of China (English)

    王艳蓉; 朱慧珑; 赵超; 陈大鹏; 叶甜春; 杨红; 徐昊; 王晓磊; 罗维春; 祁路伟; 张淑祥; 王文武; 闫江

    2015-01-01

    A multi-deposition multi-annealing technique (MDMA) is introduced into the process of high-k/metal gate MOSFET for the gate last process to effectively reduce the gate leakage and improve the device’s performance. In this paper, we systematically investigate the electrical parameters and the time-dependent dielectric breakdown (TDDB) characteristics of positive channel metal oxide semiconductor (PMOS) under different MDMA process conditions, including the depo-sition/annealing (D&A) cycles, the D&A time, and the total annealing time. The results show that the increases of the number of D&A cycles (from 1 to 2) and D&A time (from 15 s to 30 s) can contribute to the results that the gate leakage current decreases by about one order of magnitude and that the time to fail (TTF) at 63.2% increases by about several times. However, too many D&A cycles (such as 4 cycles) make the equivalent oxide thickness (EOT) increase by about 1 ˚A and the TTF of PMOS worsen. Moreover, different D&A times and numbers of D&A cycles induce different breakdown mechanisms.

  20. High-sensitivity assay for Hg (II) and Ag (I) ion detection: A new class of droplet digital PCR logic gates for an intelligent DNA calculator.

    Science.gov (United States)

    Cheng, Nan; Zhu, Pengyu; Xu, Yuancong; Huang, Kunlun; Luo, Yunbo; Yang, Zhansen; Xu, Wentao

    2016-10-15

    The first example of droplet digital PCR logic gates ("YES", "OR" and "AND") for Hg (II) and Ag (I) ion detection has been constructed based on two amplification events triggered by a metal-ion-mediated base mispairing (T-Hg(II)-T and C-Ag(I)-C). In this work, Hg(II) and Ag(I) were used as the input, and the "true" hierarchical colors or "false" green were the output. Through accurate molecular recognition and high sensitivity amplification, positive droplets were generated by droplet digital PCR and viewed as the basis of hierarchical digital signals. Based on this principle, YES gate for Hg(II) (or Ag(I)) detection, OR gate for Hg(II) or Ag(I) detection and AND gate for Hg(II) and Ag(I) detection were developed, and their sensitively and selectivity were reported. The results indicate that the ddPCR logic system developed based on the different indicators for Hg(II) and Ag(I) ions provides a useful strategy for developing advanced detection methods, which are promising for multiplex metal ion analysis and intelligent DNA calculator design applications.

  1. Using in-process measurements of open-gate structures to evaluate threshold voltage of normally-off GaN-based high electron mobility transistors

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Bin; Ma, Xiao-Hua, E-mail: xhma@xidian.edu.cn, E-mail: yhao@xidian.edu.cn; Chen, Wei-Wei; Zhu, Jie-Jie; Xie, Yong [School of Advanced Materials and Nanotechnology, Xidian University, Xi' an 710071 (China); Key Lab of Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi' an 710071 (China); Zhao, Sheng-Lei; Chen, Yong-He; Zhang, Jin-Cheng; Hao, Yue, E-mail: xhma@xidian.edu.cn, E-mail: yhao@xidian.edu.cn [Key Lab of Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi' an 710071 (China)

    2015-10-19

    The parameters of open-gate structures treated with different etching time were monitored during the gate recess process, and their impacts on the threshold voltage (V{sub th}) of final fabricated AlGaN/GaN high electron mobility transistors (HEMTs) based on open-gate structures were discussed in this paper. It is found that V{sub th} can exceed 0 V when channel resistance in the recessed region (R{sub on-open}) increases over ∼275 Ω mm, maximum current (I{sub Dmax}) decreases below ∼29 mA/mm, or recessed barrier thickness (t{sub RB}) is below ∼7.5 nm. In addition, t{sub RB} obtained by atomic force microscopy measurements and C-V measurements are also compared. Finally, theoretical common criteria based on the experimental results of this work for t{sub RB} and R{sub on-open} were established to evaluate the V{sub th} of a regular normally-off AlGaN/GaN HEMTs. The results indicate that these parameters of open-gate structure can be utilized to achieve normally-off HEMTs with controllable V{sub th}.

  2. High-Resolution Time-to-Digital Converter in Field Programmable Gate Array

    CERN Document Server

    Aloisio, A; Cicalese, R; Giordano, R; Izzo, V; Loffredo, S; Lomoro, R

    2008-01-01

    Two high-resolution time-interval measuring systems implemented in a SRAM-based FPGA device are presented. The two methods ought to be used for time interpolation within the system clock cycle. We designed and built a PCB hosting a Virtex-5 Xilinx FPGA. We exploited high stability oscillators to test the two different architectures. In the first method, dedicated carry lines are used to perform fine time measurement, while in the second one a differential tapped delay line is used. In this paper we compare the two architectures and show their performance in terms of stability and resolution.

  3. High performance ZnO nanowire field effect transistors with organic gate nanodielectrics: effects of metal contacts and ozone treatment

    Energy Technology Data Exchange (ETDEWEB)

    Ju, Sanghyun [School of Electrical and Computer Engineering, and Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907 (United States); Lee, Kangho [School of Electrical and Computer Engineering, and Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907 (United States); Yoon, Myung-Han [Department of Chemistry and Materials Research Center, and Institute for Nanoelectronics and Computing, Northwestern University, Evanston, IL 60208-3113 (United States); Facchetti, Antonio [Department of Chemistry and Materials Research Center, and Institute for Nanoelectronics and Computing, Northwestern University, Evanston, IL 60208-3113 (United States); Marks, Tobin J [Department of Chemistry and Materials Research Center, and Institute for Nanoelectronics and Computing, Northwestern University, Evanston, IL 60208-3113 (United States); Janes, David B [School of Electrical and Computer Engineering, and Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907 (United States)

    2007-04-18

    High performance ZnO nanowire field effect transistors (NW-FETs) were fabricated using a nanoscopic self-assembled organic gate insulator and characterized in terms of conventional device performance metrics. To optimize device performance and understand the effects of interface properties, devices were fabricated with both Al and Au/Ti source/drain contacts, and device electrical properties were characterized following annealing and ozone treatment. Ozone-treated single ZnO NW-FETs with Al contacts exhibited an on-current (I{sub on}) of {approx}4 {mu}A at 0.9 V{sub gs} and 1.0 V{sub ds}, a threshold voltage (V{sub th}) of 0.2 V, a subthreshold slope (S) of {approx}130 mV/decade, an on-off current ratio (I{sub on}:I{sub off}) of {approx}10{sup 7}, and a field effect mobility ({mu}{sub eff}) of {approx}1175 cm{sup 2} V{sup -1} s{sup -1}. In addition, ozone-treated ZnO NW-FETs consistently retained the enhanced device performance metrics after SiO{sub 2} passivation. A 2D device simulation was performed to explain the enhanced device performance in terms of changes in interfacial trap and fixed charge densities.

  4. High performance ZnO nanowire field effect transistors with organic gate nanodielectrics: effects of metal contacts and ozone treatment

    Science.gov (United States)

    Ju, Sanghyun; Lee, Kangho; Yoon, Myung-Han; Facchetti, Antonio; Marks, Tobin J.; Janes, David B.

    2007-04-01

    High performance ZnO nanowire field effect transistors (NW-FETs) were fabricated using a nanoscopic self-assembled organic gate insulator and characterized in terms of conventional device performance metrics. To optimize device performance and understand the effects of interface properties, devices were fabricated with both Al and Au/Ti source/drain contacts, and device electrical properties were characterized following annealing and ozone treatment. Ozone-treated single ZnO NW-FETs with Al contacts exhibited an on-current (Ion) of ~4 µA at 0.9 Vgs and 1.0 Vds, a threshold voltage (Vth) of 0.2 V, a subthreshold slope (S) of ~130 mV/decade, an on-off current ratio (Ion:Ioff) of ~107, and a field effect mobility (μeff) of ~1175 cm2 V-1 s-1. In addition, ozone-treated ZnO NW-FETs consistently retained the enhanced device performance metrics after SiO2 passivation. A 2D device simulation was performed to explain the enhanced device performance in terms of changes in interfacial trap and fixed charge densities.

  5. A novel high performance SemiSJ-CSTBT with p-pillar under the bottom of the trench gate

    Science.gov (United States)

    Yan, Jia; Hong, Chen; Ji, Tan; Shuojin, Lu; Yangjun, Zhu

    2016-08-01

    A novel high performance SemiSJ-CSTBT is proposed with the p-pillar under the bottom of the trench gate. The inserted p-pillar with the neighbouring n-drift region forms a lateral P/N junction, which can adjust the electric distribution in the forward-blocking mode to achieve a higher breakdown voltage compared to the conventional CSTBT. Also, the p-pillar can act as a hole collector at turn-off, which significantly enhances the turn-off speed and obtains a lower turn-off switching loss. Although the turn-off switching loss decreases as the depth of the p-pillar increases, there is no need for a very deep p-pillar. The associated voltage overshoot at turn-off increases dramatically with increasing the depth of p-pillar, which may cause destruction of the devices. Plus, this will add difficulty and cost to the manufacturing process of this new structure. Therefore, the proposed SemiSJ-CSTBT offers considerably better robustness compared to the conventional CSTBT and SJ-CSTBT. The simulation results show that the SemiSJ-CSTBT exhibits an increase in breakdown voltage by 160 V (13%) and a reduction of turn-off switching loss by approximately 15%. Project supported by the National Major Science and Technology Special Project of China (No. 2013ZX02305005-002) and the Major Program of the National Natural Science Foundation of China (No. 51490681).

  6. Strong Coupling Cavity QED with Gate-Defined Double Quantum Dots Enabled by a High Impedance Resonator

    Directory of Open Access Journals (Sweden)

    A. Stockklauser

    2017-03-01

    Full Text Available The strong coupling limit of cavity quantum electrodynamics (QED implies the capability of a matterlike quantum system to coherently transform an individual excitation into a single photon within a resonant structure. This not only enables essential processes required for quantum information processing but also allows for fundamental studies of matter-light interaction. In this work, we demonstrate strong coupling between the charge degree of freedom in a gate-defined GaAs double quantum dot (DQD and a frequency-tunable high impedance resonator realized using an array of superconducting quantum interference devices. In the resonant regime, we resolve the vacuum Rabi mode splitting of size 2g/2π=238  MHz at a resonator linewidth κ/2π=12  MHz and a DQD charge qubit decoherence rate of γ_{2}/2π=40  MHz extracted independently from microwave spectroscopy in the dispersive regime. Our measurements indicate a viable path towards using circuit-based cavity QED for quantum information processing in semiconductor nanostructures.

  7. Comprehensive study and design of scaled metal/high-k/Ge gate stacks with ultrathin aluminum oxide interlayers

    Energy Technology Data Exchange (ETDEWEB)

    Asahara, Ryohei; Hideshima, Iori; Oka, Hiroshi; Minoura, Yuya; Hosoi, Takuji, E-mail: hosoi@mls.eng.osaka-u.ac.jp; Shimura, Takayoshi; Watanabe, Heiji [Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Ogawa, Shingo [Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Toray Research Center Inc., 3-3-7 Sonoyama, Otsu, Shiga 520-8567 (Japan); Yoshigoe, Akitaka; Teraoka, Yuden [Japan Atomic Energy Agency, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan)

    2015-06-08

    Advanced metal/high-k/Ge gate stacks with a sub-nm equivalent oxide thickness (EOT) and improved interface properties were demonstrated by controlling interface reactions using ultrathin aluminum oxide (AlO{sub x}) interlayers. A step-by-step in situ procedure by deposition of AlO{sub x} and hafnium oxide (HfO{sub x}) layers on Ge and subsequent plasma oxidation was conducted to fabricate Pt/HfO{sub 2}/AlO{sub x}/GeO{sub x}/Ge stacked structures. Comprehensive study by means of physical and electrical characterizations revealed distinct impacts of AlO{sub x} interlayers, plasma oxidation, and metal electrodes serving as capping layers on EOT scaling, improved interface quality, and thermal stability of the stacks. Aggressive EOT scaling down to 0.56 nm and very low interface state density of 2.4 × 10{sup 11 }cm{sup −2}eV{sup −1} with a sub-nm EOT and sufficient thermal stability were achieved by systematic process optimization.

  8. A Secure and Reliable High-Performance Field Programmable Gate Array for Information Processing

    Science.gov (United States)

    2012-03-01

    adopted by the ASIC industry. As a result, this tool has broad support for commercial hardware description languages such as Verilog and VHDL . A...Switch box SRAM Static Random Access Memory VHDL Very High Speed Integrated Circuit Hardware Description Language VLSI Very Large Scale Integration VPR Versatile Place and Route

  9. A rugged 650 V SOI-based high-voltage half-bridge IGBT gate driver IC for motor drive applications

    Science.gov (United States)

    Hua, Qing; Li, Zehong; Zhang, Bo; Chen, Weizhong; Huang, Xiangjun; Feng, Yuxiang

    2015-05-01

    This paper proposes a rugged high-voltage N-channel insulated gate bipolar transistor (IGBT) gate driver integrated circuit. The device integrates a high-side and a low-side output stages on a single chip, which is designed specifically for motor drive applications. High-voltage level shift technology enables the high-side stage of this device to operate up to 650 V. The logic inputs are complementary metal oxide semiconductor (CMOS)/transistor transistor logic compatible down to 3.3 V. Undervoltage protection functionality with hysteresis characteristic has also been integrated to enhance the device reliability. The device is fabricated in a 1.0 μm, 650 V high-voltage bipolar CMOS double-diffused metal oxide semiconductor (BCD) on silicon-on-insulator (SOI) process. Deep trench dielectric isolation technology is employed to provide complete electrical isolation with advantages such as reduced parasitic effects, excellent noise immunity and low leakage current. Experimental results show that the isolation voltage of this device can be up to approximately 779 V at 25°C, and the leakage current is only 5 nA at 650 V, which is 15% higher and 67% lower than the conventional ones. In addition, it delivers an excellent thermal stability and needs very low quiescent current and offers a high gate driver capability which is needed to adequately drive IGBTs that have large input capacitances.

  10. Thermal characteristics investigation of high voltage grounded gate-LDMOS under ESD stress conditions

    Energy Technology Data Exchange (ETDEWEB)

    Sun Weifeng; Qian Qinsong; Wang Wen; Yi Yangbo, E-mail: swffrog@seu.edu.c [National ASIC System Engineering Research Center, Southeast University, Nanjing 210096 (China)

    2009-10-15

    The thermal characteristics of high voltage gg-LDMOS under ESD stress conditions are investigated in detail based on the Sentaurus process and device simulators. The total heat and lattice temperature distributions along the Si-SiO{sub 2} interface under different stress conditions are presented and the physical mechanisms are discussed in detail. The influence of structure parameters on peak lattice temperature is also discussed, which is useful for designers to optimize the parameters of LDMSO for better ESD performance.

  11. Thermal characteristics investigation of high voltage grounded gate-LDMOS under ESD stress conditions

    Institute of Scientific and Technical Information of China (English)

    Sun Weifeng; Qian Qinsong; Wang Wen; Yi Yangbo

    2009-01-01

    The thermal characteristics of high voltage gg-LDMOS under ESD stress conditions are investigated in detail based on the Sentaurus process and device simulators. The total heat and lattice temperature distributions along the Si-SiO_2 interface under different stress conditions are presented and the physical mechanisms are discussed in detail. The influence of structure parameters on peak lattice temperature is also discussed, which is useful for designers to optimize the parameters of LDMSO for better ESD performance.

  12. High K Oxide Insulated Gate Group III Nitride-Based FETs

    Science.gov (United States)

    2014-03-21

    the physical and electrical properties of high-k dielectric oxides on gallium nitride were explored. The efficacies of several cleaning procedures...surface roughening. Parameters examined included the oxide composition (AI203, Ti02, and Ga203), the gallium nitride crystallographic orientation (c...and m-plane), and its crystal polarity (Ga- anc N-polar). 15. SUBJECT TERMS Gallium nitride , oxides, atomic layer deposition, capitance-voltage

  13. Gate length scaling effect on high-electron mobility transistors devices using AlGaN/GaN and AlInN/AlN/GaN heterostructures.

    Science.gov (United States)

    Liao, S Y; Lu, C C; Chang, T; Huang, C F; Cheng, C H; Chang, L B

    2014-08-01

    Compared to AlGaN/GaN HEMT with 0.15 μm T-gate length, the AlInN/AlN/GaN one exhibits much higher current density and transconductance of 1558 mA/mm at Vd = 2 V and 330 mS/mm, respectively. The high extrinsic ft and fmax of 82 GHz and 70 GHz are extracted from AlInN/AlN/GaN HEMT. Besides, we find that the transconductance roll-off is significant in AlGaN/GaN, but largely improved in AlInN/AlN/GaN HEMT, suggesting that the high carrier density and lattice-matched epitaxial heterostructure is important to reach both large RF output power and high operation frequency, especially for an aggressively gate length scaling.

  14. Fluorescence-based high-throughput functional profiling of ligand-gated ion channels at the level of single cells.

    Directory of Open Access Journals (Sweden)

    Sahil Talwar

    Full Text Available Ion channels are involved in many physiological processes and are attractive targets for therapeutic intervention. Their functional properties vary according to their subunit composition, which in turn varies in a developmental and tissue-specific manner and as a consequence of pathophysiological events. Understanding this diversity requires functional analysis of ion channel properties in large numbers of individual cells. Functional characterisation of ligand-gated channels involves quantitating agonist and drug dose-response relationships using electrophysiological or fluorescence-based techniques. Electrophysiology is limited by low throughput and high-throughput fluorescence-based functional evaluation generally does not enable the characterization of the functional properties of each individual cell. Here we describe a fluorescence-based assay that characterizes functional channel properties at single cell resolution in high throughput mode. It is based on progressive receptor activation and iterative fluorescence imaging and delivers >100 dose-responses in a single well of a 384-well plate, using α1-3 homomeric and αβ heteromeric glycine receptor (GlyR chloride channels as a model system. We applied this assay with transiently transfected HEK293 cells co-expressing halide-sensitive yellow fluorescent protein and different GlyR subunit combinations. Glycine EC50 values of different GlyR isoforms were highly correlated with published electrophysiological data and confirm previously reported pharmacological profiles for the GlyR inhibitors, picrotoxin, strychnine and lindane. We show that inter and intra well variability is low and that clustering of functional phenotypes permits identification of drugs with subunit-specific pharmacological profiles. As this method dramatically improves the efficiency with which ion channel populations can be characterized in the context of cellular heterogeneity, it should facilitate systems

  15. A lower baseline glomerular filtration rate predicts high mortality and newly cerebrovascular accidents in acute ischemic stroke patients.

    Science.gov (United States)

    Dong, Kai; Huang, Xiaoqin; Zhang, Qian; Yu, Zhipeng; Ding, Jianping; Song, Haiqing

    2017-02-01

    Chronic kidney disease (CKD) is gradually recognized as an independent risk factor for cardiovascular and cardio-/cerebrovascular disease. This study aimed to examine the association of the estimated glomerular filtration rate (eGFR) and clinical outcomes at 3 months after the onset of ischemic stroke in a hospitalized Chinese population.Totally, 972 patients with acute ischemic stroke were enrolled into this study. Modified of Diet in Renal Disease (MDRD) equations were used to calculate eGFR and define CKD. The site and degree of the stenosis were examined. Patients were followed-up for 3 months. Endpoint events included all-cause death and newly ischemic events. The multivariate logistic model was used to determine the association between renal dysfunction and patients' outcomes.Of all patients, 130 patients (13.4%) had reduced eGFR (stroke patients. A low baseline eGFR was also a strong independent predictor for newly ischemic events in ICAS patients.

  16. Effect of High-k Oxide on Double Gate Transistor Embedded in RF Colpitts Oscillator

    Directory of Open Access Journals (Sweden)

    M. Bella

    2016-11-01

    Full Text Available The Linear Time Variant (LTV model of phase noise is considered. It is based on the Impulse Sensitivity Function (ISF which describes carefully the sensitivity of an oscillator to a parasite impulse current injection in different nodes of the circuit. The obtained results pointed out that the ISF function is sinusoidal and its period is nearly the same of the oscillator output signal for different dielectric oxide. It also states that the phase noise of a Colpitts oscillator is not affected by the use of the high-k materials. Finally this method, if extended, is a good tool to investigate a perturbation response on such circuits.

  17. Hf-based high-k materials for Si nanocrystal floating gate memories

    Directory of Open Access Journals (Sweden)

    Sahu Bhabani

    2011-01-01

    Full Text Available Abstract Pure and Si-rich HfO2 layers fabricated by radio frequency sputtering were utilized as alternative tunnel oxide layers for high-k/Si-nanocrystals-SiO2/SiO2 memory structures. The effect of Si incorporation on the properties of Hf-based tunnel layer was investigated. The Si-rich SiO2 active layers were used as charge storage layers, and their properties were studied versus deposition conditions and annealing treatment. The capacitance-voltage measurements were performed to study the charge trapping characteristics of these structures. It was shown that with specific deposition conditions and annealing treatment, a large memory window of about 6.8 V is achievable at a sweeping voltage of ± 6 V, indicating the utility of these stack structures for low-operating-voltage nonvolatile memory devices.

  18. Low voltage and high ON/OFF ratio field-effect transistors based on CVD MoS2 and ultra high-k gate dielectric PZT.

    Science.gov (United States)

    Zhou, Changjian; Wang, Xinsheng; Raju, Salahuddin; Lin, Ziyuan; Villaroman, Daniel; Huang, Baoling; Chan, Helen Lai-Wa; Chan, Mansun; Chai, Yang

    2015-05-21

    MoS2 and other atomic-level thick layered materials have been shown to have a high potential for outperforming Si transistors at the scaling limit. In this work, we demonstrate a MoS2 transistor with a low voltage and high ON/OFF ratio. A record small equivalent oxide thickness of ∼1.1 nm has been obtained by using ultra high-k gate dielectric Pb(Zr0.52Ti0.48)O3. The low threshold voltage (swing of 85.9 mV dec(-1), the high ON/OFF ratio of ∼10(8) and the negligible hysteresis ensure a high performance of the MoS2 transistor operating at 1 V. The extracted field-effect mobility of 1-10 cm(2) V(-1) s(-1) suggests a high crystalline quality of the CVD-grown MoS2 flakes. The combination of the two-dimensional layered semiconductor and the ultra high-k dielectric may enable the development of low-power electronic applications.

  19. Synthesis of Cerium Dioxide High-k Thin Films as a Gate Dielectric in MOS Capacitor

    Directory of Open Access Journals (Sweden)

    Anil G. Khairnar

    2013-07-01

    Full Text Available In the present study, the Al/CeO2 / p-Si MOS capacitor was fabricated by depositing the Aluminium (Al metal layer by thermal evaporation technique on sol-gel derived CeO2 high-k thin films on p-Si substrate. The deposited CeO2 films were characterized by Ellipsometer to study the refractive index that is determined to be 3.62. The FTIR analysis was carried out to obtain chemical bonding characteristics. Capacitance-voltage measurements of Al/CeO2 /p-Si MOS capacitor were carried out to determine the dielectric constant, equivalent oxide thickness (EOT and flat band shift (VFB for the deposited CeO2 film of 16.22, 1.62 nm and 0.7 V respectively. The conductance voltage curve was used to determine the interface trap density (Dit at the CeO2 / p-Si interface that is calculated to be 1.29 × 1013 cm – 2 eV – 1 for measurement frequency of 500 kHz.

  20. Thermally oxidized 2D TaS2 as a highgate dielectric for MoS2 field-effect transistors

    Science.gov (United States)

    Chamlagain, Bhim; Cui, Qingsong; Paudel, Sagar; Ming-Cheng Cheng, Mark; Chen, Pai-Yen; Zhou, Zhixian

    2017-09-01

    We report a new approach to integrating high-κ dielectrics in both bottom- and top-gated MoS2 field-effect transistors (FETs) through thermal oxidation and mechanical assembly of layered two-dimensional (2D) TaS2. Combined x-ray photoelectron spectroscopy (XPS), optical microscopy, atomic force microscopy (AFM), and capacitance-voltage (C-V) measurements confirm that multilayer TaS2 flakes can be uniformly transformed to Ta2O5 with a high dielectric constant of ~15.5 via thermal oxidation, while preserving the geometry and ultra-smooth surfaces of 2D TMDs. Top-gated MoS2 FETs fabricated using the thermally oxidized Ta2O5 as gate dielectric demonstrate a high current on/off ratio approaching 106, a subthreshold swing (SS) down to 61 mV/dec, and a field-effect mobility exceeding 60 cm2 V-1 s-1 at room temperature, indicating high dielectric quality and low interface trap density.

  1. Modeling of high-quality factor XNOR gate using quantum-dot semiconductor optical amplifiers at 1 Tb/s

    Energy Technology Data Exchange (ETDEWEB)

    Kotd, Amer, E-mail: amer_22003@yahoo.com, E-mail: kotb@phys.uconn.edu [Department of Physics, Faculty of Science, Fayoum University, Fayoum, (Egypt)

    2015-06-15

    The modeling of all-optical logic XNOR gate is realized by a series combination of XOR and INVERT gates. This Boolean function is simulated by using Mach-Zehnder interferometers (MZIs) utilizing quantum-dots semiconductor optical amplifiers (QDs-SOAs). The study is carried out when the effect of amplified spontaneous emission (ASE) is included. The dependence of the output quality factor (Q-factor) on signals and QDs-SOAs' parameters is also investigated and discussed. The simulation is conducted under a repetition rate of ∼1 Tb/s. (author)

  2. Baseline HbA1c to Identify High-Risk Gestational Diabetes: Utility in Early vs Standard Gestational Diabetes.

    Science.gov (United States)

    Sweeting, Arianne N; Ross, Glynis P; Hyett, Jon; Molyneaux, Lynda; Tan, Kris; Constantino, Maria; Harding, Anna Jane; Wong, Jencia

    2017-01-01

    The increasing prevalence of gestational diabetes mellitus (GDM) necessitates risk stratification directing limited antenatal resources to those at greatest risk. Recent evidence demonstrates that an early pregnancy glycated hemoglobin (HbA1c ≥5.9% (41 mmol/mol) predicts adverse pregnancy outcomes. To determine the optimal HbA1c threshold for adverse pregnancy outcomes in GDM in a treated multiethnic cohort and whether this differs in women diagnosed 5.9% (41 mmol/mol) was associated with the greatest risk of large-for-gestational-age (odds ratio [95% confidence interval] = 2.7 [1.5-4.9]), macrosomia (3.5 [1.4-8.6]), cesarean section (3.6 [2.1-6.2]), and hypertensive disorders (2.6 [1.1-5.8]). In early GDM, similar HbA1c associations were seen; however, lower HbA1c correlated with the greatest risk of small-for-gestational-age (P trend = 0.004) and prevalence of neonatal hypoglycemia. Baseline HbA1c >5.9% (41 mmol/mol) identifies an increased risk of large-for-gestational-age, macrosomia, cesarean section, and hypertensive disorders in standard GDM. Although similar associations are seen in early GDM, higher HbA1c levels do not adequately capture risk-limiting utility as a triage tool in this cohort.

  3. High performance thin film transistor (flex-TFT) with textured nanostructure ZnO film channel fabricated by exploiting electric double layer gate insulator

    Science.gov (United States)

    Ghimire, Rishi Ram; Raychaudhuri, A. K.

    2017-01-01

    We report a flexible thin film transistor (flex-TFT) fabricated on a commonly available polyimide (Kapton®) tape with a channel of highly textured nanocrystalline ZnO film grown by pulsed laser deposition. The flex-TFT with an electric double layer (EDL) gate insulator shows a low threshold for operation (Vth ≤ 1 V), an ON/OFF ratio reaching ≈107 and a subthreshold swing ≈75 mV/dec. The superior performance is enabled by a high saturation mobility (μs ≈ 70 cm2/V s) of the highly textured nanocrystalline channel. The low Vth arises from large charge density (≈1014/cm2) induced into the channel by EDL gate insulator. The large charge density induced by the EDL gate dielectric also enhances the Hall mobility in the film and brings down the sheet resistance by nearly 2 orders, which leads to large ON/OFF ratio. The flex-TFT operation can be sustained with reproducibility when the TFT is bent down to a radius of curvature ≈2 cm.

  4. Multi-technique Approach for the Evaluation of the Crystalline Phase of Ultrathin High-k Gate Oxide Films

    Science.gov (United States)

    Bersch, E.; LaRose, J. D.; Wells, I.; Consiglio, S.; Clark, R. D.; Leusink, G. J.; Matyi, R. J.; Diebold, A. C.

    2011-11-01

    In order to continue scaling metal oxide semiconductor field effect transistors (MOSFETs) with HfO2 gate oxides, efforts are being made to further improve the deposited high-k film properties. Recently, a process whereby an HfO2 film is deposited through a series of depositions and anneals (so-called DADA process) has been shown to result in films that give rise to MOS capacitors (MOSCAPs) which are electrically scaled compared to MOSCAPs with HfO2 films that only received post deposition anneals (PDA) or no anneals. We have measured as-deposited, DADA and PDA HfO2 films using four measurement techniques, all of which are non-destructive and capable of being used for in-line processing, to evaluate their crystallinity and crystalline phases. Grazing incidence in-plane X-ray diffraction was used to determine the crystalline phases of the HfO2 films. We observed the crystalline phases of these films to be process dependent. Additionally, X-ray and UV photoelectron spectroscopy were used to show the presence of crystallinity in the films. As a fourth technique, spectroscopic ellipsometry was used to determine if the crystalline phases were monoclinic. The combination of techniques was useful in that XPS and UPS were able to confirm the amorphous nature of a 30 cycle DADA film, as measured by GIIXRD, and GIIXRD was able to help us interpret the SE data as being an indication of the monoclinic phase of HfO2.

  5. Investigation of abrupt degradation of drain current caused by under-gate crack in AlGaN/GaN high electron mobility transistors during high temperature operation stress

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Chang; Liao, XueYang; Li, RuGuan; Wang, YuanSheng; Chen, Yiqiang, E-mail: yiqiang-chen@hotmail.com; Su, Wei; Liu, Yuan; Wang, Li Wei; Lai, Ping; Huang, Yun; En, YunFei [Science and Technology on Reliability Physics and Application of Electronic Component Laboratory, The 5th Electronics Research Institute of the Ministry of Industry and Information Technology, 510610 Guangzhou (China)

    2015-09-28

    In this paper, we investigate the degradation mode and mechanism of AlGaN/GaN based high electron mobility transistors (HEMTs) during high temperature operation (HTO) stress. It demonstrates that there was abrupt degradation mode of drain current during HTO stress. The abrupt degradation is ascribed to the formation of crack under the gate which was the result of the brittle fracture of epilayer based on failure analysis. The origin of the mechanical damage under the gate is further investigated and discussed based on top-down scanning electron microscope, cross section transmission electron microscope and energy dispersive x-ray spectroscopy analysis, and stress simulation. Based on the coupled analysis of the failure physical feature and stress simulation considering the coefficient of thermal expansion (CTE) mismatch in different materials in gate metals/semiconductor system, the mechanical damage under the gate is related to mechanical stress induced by CTE mismatch in Au/Ti/Mo/GaN system and stress concentration caused by the localized structural damage at the drain side of the gate edge. These results indicate that mechanical stress induced by CTE mismatch of materials inside the device plays great important role on the reliability of AlGaN/GaN HEMTs during HTO stress.

  6. Influence of respiratory gating, image filtering, and animal positioning on high-resolution electrocardiography-gated murine cardiac single-photon emission computed tomography

    NARCIS (Netherlands)

    Wu, Chao; Vaissier, Pieter E. B.; Vastenhouw, Brendan; de Jong, Johan R.; Slart, Riemer H. J. A.; Beekman, Freek J.

    2015-01-01

    Cardiac parameters obtained from single-photon emission computed tomographic (SPECT) images can be affected by respiratory motion, image filtering, and animal positioning. We investigated the influence of these factors on ultra-high-resolution murine myocardial perfusion SPECT. Five mice were inject

  7. Increased risk of coronary artery calcification progression in subjects with high baseline Lp(a) levels: The Kangbuk Samsung Health Study.

    Science.gov (United States)

    Cho, Jung Hwan; Lee, Da Young; Lee, Eun Seo; Kim, Jihyun; Park, Se Eun; Park, Cheol-Young; Lee, Won-Young; Oh, Ki-Won; Park, Sung-Woo; Rhee, Eun-Jung

    2016-11-01

    Results from previous studies support the association of lipoprotein(a) [Lp(a)] levels and coronary artery disease risk. In this study, we analyzed the association between baseline Lp(a) levels and future progression of coronary artery calcification (CAC) in apparently healthy Korean adults. A total of 2611 participants (mean age: 41years, 92% mend) who underwent a routine health check-up in 2010 and 2014 were enrolled. Coronary artery calcium score (CACS) were measured by multi-detector computed tomography. Baseline Lp(a) was measured by high-sensitivity immunoturbidimetric assay. Progression of CAC was defined as a change in CACS >0 over four years. Bivariate correlation analyses with baseline Lp(a) and other metabolic parameters revealed age, total cholesterol, HDL-C, LDL-C and CACS to have a significant positive correlation, while body weight, fasting glucose level, blood pressure and triglyceride level were negatively correlated with baseline Lp(a) level. After four years of follow-up, 635 subjects (24.3%) had CAC progression. The participants who had CAC progression were older, composed of more men, more obese, and had higher fasting glucose levels and worse baseline lipid profiles compared to those who did not have CAC progression. The mean serum Lp(a) level was significantly higher in subjects who had CAC progression compared to those who did not (32.5 vs. 28.9mg/dL, p<0.01). When the risk for CAC progression according to baseline Lp(a) was calculated, those with Lp(a) level≥50mg/dL had an odds ratio of 1.333 (95% CI 1.027-1.730) for CAC progression compared to those with Lp(a)<50mg/dL after adjusting for confounding factors. In this study, the subjects who had higher Lp(a) were at significantly higher risk for CAC progression after four years of follow-up, suggesting the role of high Lp(a) in CAC progression. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. Role of baseline HIV-1 DNA level in highly-experienced patients receiving raltegravir, etravirine and darunavir/ritonavir regimen (ANRS139 TRIO trial.

    Directory of Open Access Journals (Sweden)

    Charlotte Charpentier

    Full Text Available OBJECTIVE: In the ANRS 139 TRIO trial, the use of 3 new active drugs (raltegravir, etravirine, and darunavir/ritonavir, resulted in a potent and sustained inhibition of viral replication in multidrug-resistant treatment-experienced patients. The aim of this virological sub-study of the ANRS 139 TRIO trial was to assess: (i the evolution of HIV-1 DNA over the first year; and (ii the association between baseline HIV-1 DNA and virological outcome. METHODS: Among the 103 HIV-1-infected patients included in the ANRS-139 TRIO trial, HIV-1 DNA specimens were available for 92, 84, 88, and 83 patients at Week (W0, W12, W24, and W48, respectively. Quantification of total HIV-1 DNA was performed by using the commercial kit "Generic HIV DNA Cell" (Biocentric, Bandol, France. RESULTS: Baseline median HIV-1 DNA of patients displaying virological success (n= 61, viral blip (n= 20, and virological failure (n = 11 were 2.34 log(10 copies/10(6 PBMC (IQR= 2.15-2.66, 2.42 (IQR = 2.12-2.48, and 2.68 (IQR= 2.46-2.83, respectively. Although not statistically significant, patients exhibiting virological success or viral blip had a tendency to display lower baseline HIV-1 DNA than patients experiencing virological failure (P = 0.06. Median decrease of HIV-1 DNA between baseline and W48 was -0.13 log(10 copies/10(6 PBMC (IQR = -0.34 to +0.10, mainly explained by the evolution from W0 to W4. No more changes were observed in the W4-W48 period. CONCLUSIONS: In highly-experienced multidrug-resistant patients, HIV-1 DNA slightly decreased during the first month and then remained stable during the first year of highly potent antiretroviral regimen. In this population, baseline HIV-1 DNA might help to better predict the virological response and to tailor clinical therapeutic management as more aggressive therapeutic choices in patients with higher baseline HIV-1 DNA.

  9. Cadmium-free quantum dots as time-gated bioimaging probes in highly-autofluorescent human breast cancer cells.

    Science.gov (United States)

    Mandal, Gopa; Darragh, Molly; Wang, Y Andrew; Heyes, Colin D

    2013-01-21

    We report cadmium-free, biocompatible (Zn)CuInS(2) quantum dots with long fluorescence lifetimes as superior bioimaging probes using time-gated detection to suppress cell autofluorescence and improve the signal : background ratio by an order of magnitude. These results will be important for developing non-toxic fluorescence imaging probes for ultrasensitive biomedical diagnostics.

  10. Gate stack technology for nanoscale devices

    Directory of Open Access Journals (Sweden)

    Byoung Hun Lee

    2006-06-01

    Full Text Available Scaling of the gate stack has been a key to enhancing the performance of complementary metal-oxide-semiconductor (CMOS field-effect transistors (FETs of past technology generations. Because the rate of gate stack scaling has diminished in recent years, the motivation for alternative gate stacks or novel device structures has increased considerably. Intense research during the last decade has led to the development of high dielectric constant (k gate stacks that match the performance of conventional SiO2-based gate dielectrics. However, many challenges remain before alternative gate stacks can be introduced into mainstream technology. We review the current status of and challenges in gate stack research for planar CMOS devices and alternative device technologies to provide insights for future research.

  11. High (≥6.5 Spontaneous and Persistent Urinary pH Is Protective of Renal Function at Baseline and during Disease Course in Idiopathic Membranous Nephropathy

    Directory of Open Access Journals (Sweden)

    Claudio Bazzi

    2015-01-01

    Full Text Available Metabolic acidosis correction in advanced renal failure slows renal function decline attributed to tubulointerstitial damage (TID reduction. No study evaluated if spontaneous baseline high urinary pH (UpH is renoprotective in patients with normal renal function and without metabolic acidosis. The study tested this hypothesis in idiopathic membranous nephropathy (IMN. Eighty-five patients (follow-up 81 ± 54 months measured UpH, serum creatinine, eGFR, protein/creatinine ratio, fractional excretion of albumin, IgG, α1-microglobulin, and urinary N-acetyl-β-D-glucosaminidase (β-NAG/creatinine ratio. Twenty-eight patients (33% had UpH ≥ 6.5 and 57 (67% pH < 6.5; high versus low UpH patients had significantly lower values of the tubulointerstitial damage (TID markers FE α1m and β-NAG and significantly better baseline renal function. These differences persisted over time in a subset of 38 patients with 5 measurements along 53 ± 26 months. In 29 patients with nephrotic syndrome (NS treated with supportive therapy (follow-up: 80 ± 52 months renal function was stable in 10 high and significantly worse in 19 low UpH patients. Steroids + cyclophosphamide treatment in 35 NS patients masks the renoprotection of high UpH. Conclusions. In IMN high and persistent UpH is associated with reduction of the proteinuric markers of tubulointerstitial damage and baseline better renal function in all patients and in NS patients treated only with supportive therapy during disease course. The factors associated with high pH-dependent renoprotection were lower values of TID markers, eGFR ≥ 60 mL/min, BP < 140/90 mmHg, and age < 55 years.

  12. Effect of annealing temperature on structural and electrical properties of high-κ YbTixOy gate dielectrics for InGaZnO thin film transistors

    Science.gov (United States)

    Pan, Tung-Ming; Chen, Fa-Hsyang; Hung, Meng-Ning

    2015-01-01

    This paper describes the effect of annealing temperature on the structural properties and electrical characteristics of high-κ YbTixOy gate dielectrics for indium-gallium-zinc-oxide (IGZO) thin-film transistors (TFTs). X-ray diffraction, x-ray photoelectron spectroscopy and atomic force microscopy were used to study the structural, chemical and morphological features, respectively, of these dielectric films annealed at 200, 300 and 400 °C. The YbTixOy IGZO TFT that had been annealed at 400 °C exhibited better electrical characteristics, such as a small threshold voltage of 0.53 V, a large field-effect mobility of 19.1 cm2 V-1 s-1, a high Ion/Ioff ratio of 2.8 × 107, and a low subthreshold swing of 176 mV dec.-1, relative to those of the systems that had been subjected to other annealing conditions. This result suggests that YbTixOy dielectric possesses a higher dielectric constant as well as lower oxygen vacancies (or defects) in the film. In addition, the instability of YbTixOy IGZO TFT was studied under positive gate-bias stress and negative gate-bias stress conditions.

  13. Direct label-free electrical immunodetection of transplant rejection protein biomarker in physiological buffer using floating gate AlGaN/GaN high electron mobility transistors.

    Science.gov (United States)

    Tulip, Fahmida S; Eteshola, Edward; Desai, Suchita; Mostafa, Salwa; Roopa, Subramanian; Evans, Boyd; Islam, Syed Kamrul

    2014-06-01

    Monokine induced by interferon gamma (MIG/CXCL9) is used as an immune biomarker for early monitoring of transplant or allograft rejection. This paper demonstrates a direct electrical, label-free detection method of recombinant human MIG with anti-MIG IgG molecules in physiologically relevant buffer environment. The sensor platform used is a biologically modified GaN-based high electron mobility transistor (HEMT) device. Biomolecular recognition capability was provided by using high affinity anti-MIG monoclonal antibody to form molecular affinity interface receptors on short N-hydroxysuccinimide-ester functionalized disulphide (DSP) self-assembled monolayers (SAMs) on the gold sensing gate of the HEMT device. A floating gate configuration has been adopted to eliminate the influences of external gate voltage. Preliminary test results with the proposed chemically treated GaN HEMT biosensor show that MIG can be detected for a wide range of concentration varying from 5 ng/mL to 500 ng/mL.

  14. Maximum frequency of oscillation of 1.3 THz obtained by using an extended drain-side recess structure in 75-nm-gate InAlAs/InGaAs high-electron-mobility transistors

    Science.gov (United States)

    Takahashi, Tsuyoshi; Kawano, Yoichi; Makiyama, Kozo; Shiba, Shoichi; Sato, Masaru; Nakasha, Yasuhiro; Hara, Naoki

    2017-02-01

    A maximum frequency of oscillation (f max) of 1.3 THz was achieved using an extended drain-side recess structure of InAlAs/InGaAs high-electron-mobility transistors (HEMTs), although the gate length was relatively long at 75 nm. The high f max was improved by reducing the drain output conductance (g d). The use of an asymmetric gate recess structure and double-side doping above and below a channel region were effective in reducing g d. Further improvements in transconductance (g m) and g d were achieved by reducing the distance between the source and gate electrodes.

  15. High (≥6.5) Spontaneous and Persistent Urinary pH Is Protective of Renal Function at Baseline and during Disease Course in Idiopathic Membranous Nephropathy.

    Science.gov (United States)

    Bazzi, Claudio; Tagliabue, Elena; Raimondi, Sara; Rizza, Virginia; Casellato, Daniela; Nangaku, Masaomi

    2015-01-01

    Metabolic acidosis correction in advanced renal failure slows renal function decline attributed to tubulointerstitial damage (TID) reduction. No study evaluated if spontaneous baseline high urinary pH (UpH) is renoprotective in patients with normal renal function and without metabolic acidosis. The study tested this hypothesis in idiopathic membranous nephropathy (IMN). Eighty-five patients (follow-up 81 ± 54 months) measured UpH, serum creatinine, eGFR, protein/creatinine ratio, fractional excretion of albumin, IgG, α1-microglobulin, and urinary N-acetyl-β-D-glucosaminidase (β-NAG)/creatinine ratio. Twenty-eight patients (33%) had UpH ≥ 6.5 and 57 (67%) pH UpH patients had significantly lower values of the tubulointerstitial damage (TID) markers FE α1m and β-NAG and significantly better baseline renal function. These differences persisted over time in a subset of 38 patients with 5 measurements along 53 ± 26 months. In 29 patients with nephrotic syndrome (NS) treated with supportive therapy (follow-up: 80 ± 52 months) renal function was stable in 10 high and significantly worse in 19 low UpH patients. Steroids + cyclophosphamide treatment in 35 NS patients masks the renoprotection of high UpH. Conclusions. In IMN high and persistent UpH is associated with reduction of the proteinuric markers of tubulointerstitial damage and baseline better renal function in all patients and in NS patients treated only with supportive therapy during disease course. The factors associated with high pH-dependent renoprotection were lower values of TID markers, eGFR ≥ 60 mL/min, BP < 140/90 mmHg, and age < 55 years.

  16. Quantum Gates and Circuits

    CERN Document Server

    Di Vincenzo, D P

    1997-01-01

    A historical review is given of the emergence of the idea of the quantum logic gate from the theory of reversible Boolean gates. I highlight the quantum XOR or controlled NOT as the fundamental two-bit gate for quantum computation. This gate plays a central role in networks for quantum error correction.

  17. Electric Field-induced Resistance Switching in VO2 Channels using Hybrid Gate Dielectric of High- k Ta2O5/Organic material Parylene-C

    Science.gov (United States)

    Wei, Tingting; Kanki, Teruo; Fujiwara, Kohei; Chikanari, Masashi; Tanaka, Hidekazu

    Electrostatic approach utilizing field-effect transistor (FET) with correlated electron materials provides an avenue to realize the novel devices (Mott-transistor) and to clarify condensed matter physics. In this study, we have prepared Mott-transistors using vanadium dioxide (VO2) channels and employed hybrid gate dielectric consisted of high- k material Ta2O5 and organic polymer parylene-C to trigger carrier transport modulation in VO2. Obvious resistance modulations were observed in insulating regime through time-dependent resistance measurement at varied square-shaped gate bias (VG) . Contrasting to the hysteretic response in electric double layer transistor (EDLT), an abrupt resistance switching in less than of 2-second-interval enables us to attribute such immediate modulation to pure electrostatic effect. Moreover, the maximum of resistance change was identified to appear around phase transition temperature (TMI) , which confirmed the disordered heterogeneous regime at TMI. Taking advantage of systematic modulation using VO2-based devices, we demonstrated the pronounced shifts of TMI by gate bias. Another fascinating behavior on asymmetric drop in TMI by hole-electron carrier doping was observed.

  18. Atomic Layer Deposition of Gallium Oxide Films as Gate Dielectrics in AlGaN/GaN Metal-Oxide-Semiconductor High-Electron-Mobility Transistors.

    Science.gov (United States)

    Shih, Huan-Yu; Chu, Fu-Chuan; Das, Atanu; Lee, Chia-Yu; Chen, Ming-Jang; Lin, Ray-Ming

    2016-12-01

    In this study, films of gallium oxide (Ga2O3) were prepared through remote plasma atomic layer deposition (RP-ALD) using triethylgallium and oxygen plasma. The chemical composition and optical properties of the Ga2O3 thin films were investigated; the saturation growth displayed a linear dependence with respect to the number of ALD cycles. These uniform ALD films exhibited excellent uniformity and smooth Ga2O3-GaN interfaces. An ALD Ga2O3 film was then used as the gate dielectric and surface passivation layer in a metal-oxide-semiconductor high-electron-mobility transistor (MOS-HEMT), which exhibited device performance superior to that of a corresponding conventional Schottky gate HEMT. Under similar bias conditions, the gate leakage currents of the MOS-HEMT were two orders of magnitude lower than those of the conventional HEMT, with the power-added efficiency enhanced by up to 9 %. The subthreshold swing and effective interfacial state density of the MOS-HEMT were 78 mV decade(-1) and 3.62 × 10(11) eV(-1) cm(-2), respectively. The direct-current and radio-frequency performances of the MOS-HEMT device were greater than those of the conventional HEMT. In addition, the flicker noise of the MOS-HEMT was lower than that of the conventional HEMT.

  19. Atomic Layer Deposition of Gallium Oxide Films as Gate Dielectrics in AlGaN/GaN Metal-Oxide-Semiconductor High-Electron-Mobility Transistors

    Science.gov (United States)

    Shih, Huan-Yu; Chu, Fu-Chuan; Das, Atanu; Lee, Chia-Yu; Chen, Ming-Jang; Lin, Ray-Ming

    2016-04-01

    In this study, films of gallium oxide (Ga2O3) were prepared through remote plasma atomic layer deposition (RP-ALD) using triethylgallium and oxygen plasma. The chemical composition and optical properties of the Ga2O3 thin films were investigated; the saturation growth displayed a linear dependence with respect to the number of ALD cycles. These uniform ALD films exhibited excellent uniformity and smooth Ga2O3-GaN interfaces. An ALD Ga2O3 film was then used as the gate dielectric and surface passivation layer in a metal-oxide-semiconductor high-electron-mobility transistor (MOS-HEMT), which exhibited device performance superior to that of a corresponding conventional Schottky gate HEMT. Under similar bias conditions, the gate leakage currents of the MOS-HEMT were two orders of magnitude lower than those of the conventional HEMT, with the power-added efficiency enhanced by up to 9 %. The subthreshold swing and effective interfacial state density of the MOS-HEMT were 78 mV decade-1 and 3.62 × 1011 eV-1 cm-2, respectively. The direct-current and radio-frequency performances of the MOS-HEMT device were greater than those of the conventional HEMT. In addition, the flicker noise of the MOS-HEMT was lower than that of the conventional HEMT.

  20. NAND GATE USING FINFET FOR NANOSCALE TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Nirmal,

    2010-05-01

    Full Text Available In this paper we propose Double gate transistors (FinFETs are the substitutes for bulk CMOS evolving from a single gate devices into three dimensional devices with multiple gates (double gate, triple gate or quadruple-gate devices. The main drawback of using CMOS transistors are high power consumption and high leakage current. Enormous progress has been made to scale transistors to even smaller dimensions to obtain fast switching transistors, as well as to reduce the power consumption. Even though the device characteristics are improved, high active leakage remain a problem. Leakage is found to contribute more amount of total power consumption in power-optimized FinFET logic circuits. This paper mainly deals with the various logic design styles to obtain the Leakage power savings through the judicious use of FinFET logic styles.

  1. School-Based Exercise to Lower Blood Pressure in High-Risk African American Girls: Project Design and Baseline Findings.

    Science.gov (United States)

    Ewart, Craig K.; And Others

    1995-01-01

    Describes effective methods for identifying and recruiting high risk African American ninth-grade girls to measure their fitness and assess the impact of fitness training on blood pressure. A multistage step test for fitness assessment in such girls is presented. The "Project Heart" aerobics class and control groups are described. (SM)

  2. High effort, low reward, and cardiovascular risk factors in employed Swedish men and women: baseline results from the WOLF Study.

    Science.gov (United States)

    Peter, R; Alfredsson, L; Hammar, N; Siegrist, J; Theorell, T; Westerholm, P

    1998-09-01

    To examine associations between measures of work stress (that is, the combination of high effort and low reward) and cardiovascular risk factors. Cross sectional first screening of a prospective cohort study. The study was conducted among 5720 healthy employed men and women living in the greater Stockholm area aged 19-70 years. All analyses were restricted to subjects with complete data (n = 4958). The investigation of associations between indicators of effort-reward imbalance and cardiovascular risk factors was restricted to the age group 30-55 years (n = 3427). Subjects reporting high effort and low reward at work had a higher prevalence of well known risk factors for coronary heart disease. After adjustment for relevant confounders, associations between a measure of extrinsic effort and reward (the effort-reward ratio) and hypertension (multivariate prevalence odds ratio (POR) 1.62-1.68), increased total cholesterol (upper tertile 220 mg/dl)(POR = 1.24) and the total cholesterol/high density lipoprotein(HDL)-cholesterol ratio (upper tertile 4.61)(POR 1.26-1.30) were found among men. Among women a measure of high intrinsic effort (immersion) was related to increased low density lipoprotein (LDL)-cholesterol (upper tertile 130 mg/dl)(POR 1.37-1.39). Analyses of variance showed increasing mean values of LDL cholesterol with an increasing degree of the effort-reward ratio among men and increased LDL-cholesterol among women with high levels of intrinsic effort (upper tertile of immersion). Findings lend support to the hypothesis that effort-reward imbalance represents a specific constellation of stressful experience at work related to cardiovascular risk. The relation was not explained by relevant confounders (for example, lack of physical exercise, body weight, cigarette smoking).

  3. The NOvA Data Acquistion System: A highly distributed, synchronized, continuous readout system for a long baseline neutrino experiment

    CERN Document Server

    CERN. Geneva

    2012-01-01

    The NOvA experiment at Fermi National Accelerator Lab, has been designed and optimized to perform a suite of measurements critical to our understanding of the neutrino’s properties, their oscillations and their interactions. NOvA presents a unique set of data acquisition and computing challenges due to the immense size of the detectors, the data volumes that are generated through the continuous digitization of the frontend systems, and the need to buffer the full data stream to allow for highly asynchronous triggering and extraction of physics events. These challenges are compounded by the stringent timing and synchronization requirements that are placed on the acquisition systems by the need to precisely correlate information between the accelerator complex and the remote detector locations. The NOvA Data Acquisition system has been designed and built to meets these challenges. The system utilizes a highly modular, novel acquisition and event building scheme, which has been deployed on a large hierarch...

  4. Extended-gate-type IGZO electric-double-layer TFT immunosensor with high sensitivity and low operation voltage

    Science.gov (United States)

    Liang, Lingyan; Zhang, Shengnan; Wu, Weihua; Zhu, Liqiang; Xiao, Hui; Liu, Yanghui; Zhang, Hongliang; Javaid, Kashif; Cao, Hongtao

    2016-10-01

    An immunosensor is proposed based on the indium-gallium-zinc-oxide (IGZO) electric-double-layer thin-film transistor (EDL TFT) with a separating extended gate. The IGZO EDL TFT has a field-effect mobility of 24.5 cm2 V-1 s-1 and an operation voltage less than 1.5 V. The sensors exhibit the linear current response to label-free target immune molecule in the concentrations ranging from 1.6 to 368 × 10-15 g/ml with a detection limit of 1.6 × 10-15 g/ml (0.01 fM) under an ultralow operation voltage of 0.5 V. The IGZO TFT component demonstrates a consecutive assay stability and recyclability due to the unique structure with the separating extended gate. With the excellent electrical properties and the potential for plug-in-card-type multifunctional sensing, extended-gate-type IGZO EDL TFTs can be promising candidates for the development of a label-free biosensor for public health applications.

  5. Noise Gating Solar Images

    Science.gov (United States)

    DeForest, Craig; Seaton, Daniel B.; Darnell, John A.

    2017-08-01

    I present and demonstrate a new, general purpose post-processing technique, "3D noise gating", that can reduce image noise by an order of magnitude or more without effective loss of spatial or temporal resolution in typical solar applications.Nearly all scientific images are, ultimately, limited by noise. Noise can be direct Poisson "shot noise" from photon counting effects, or introduced by other means such as detector read noise. Noise is typically represented as a random variable (perhaps with location- or image-dependent characteristics) that is sampled once per pixel or once per resolution element of an image sequence. Noise limits many aspects of image analysis, including photometry, spatiotemporal resolution, feature identification, morphology extraction, and background modeling and separation.Identifying and separating noise from image signal is difficult. The common practice of blurring in space and/or time works because most image "signal" is concentrated in the low Fourier components of an image, while noise is evenly distributed. Blurring in space and/or time attenuates the high spatial and temporal frequencies, reducing noise at the expense of also attenuating image detail. Noise-gating exploits the same property -- "coherence" -- that we use to identify features in images, to separate image features from noise.Processing image sequences through 3-D noise gating results in spectacular (more than 10x) improvements in signal-to-noise ratio, while not blurring bright, resolved features in either space or time. This improves most types of image analysis, including feature identification, time sequence extraction, absolute and relative photometry (including differential emission measure analysis), feature tracking, computer vision, correlation tracking, background modeling, cross-scale analysis, visual display/presentation, and image compression.I will introduce noise gating, describe the method, and show examples from several instruments (including SDO

  6. LEADER-4: blood pressure control in patients with type 2 diabetes and high cardiovascular risk: baseline data from the LEADER randomized trial.

    Science.gov (United States)

    Petrie, John R; Marso, Steven P; Bain, Stephen C; Franek, Edward; Jacob, Stephan; Masmiquel, Luis; Leiter, Lawrence A; Haluzik, Martin; Satman, Ilhan; Omar, Mohamed; Shestakova, Marina; Van Gaal, Luc; Mann, Johannes F; Baeres, Florian M M; Zinman, Bernard; Poulter, Neil R

    2016-06-01

    As glucagon-like peptide-1 receptor agonists lower blood pressure (BP) in type 2 diabetes mellitus (T2DM), we examined BP control in relation to targets set by international bodies prior to randomization in the Liraglutide Effect and Action in Diabetes: Evaluation of cardiovascular outcome Results (LEADER) trial. We analyzed baseline data from LEADER (NCT01179048), an ongoing phase 3B, randomized, double-blind, placebo-controlled cardiovascular outcomes trial examining the cardiovascular safety of the glucagon-like peptide-1 receptor agonist liraglutide in 9340 people with T2DM from 32 countries [age (all mean ± SD) 64 ± 7.2 years, BMI 32.5 ± 6.3 kg/m, duration of diabetes 12.7 ± 8.0 years], all of whom were at high risk for cardiovascular disease (CVD). A total of 81% (n = 7592) of participants had prior CVD and 90% (n = 8408) had a prior history of hypertension. Despite prescription of multiple antihypertensive agents at baseline, only 51% were treated to a target BP of less than 140/85 mmHg and only 26% to the recommended baseline BP target of less than 130/80 mmHg. In univariate analyses, those with prior CVD were prescribed more agents (P high cardiovascular risk, particularly outside North America. Longitudinal data from the LEADER trial may provide further insights into BP control in relation to cardiovascular outcomes in this condition.

  7. Floating gate transistors as biosensors (Conference Presentation)

    Science.gov (United States)

    Frisbie, C. Daniel

    2016-11-01

    Electrolyte gated transistors (EGTs) are a sub-class of thin film transistors that are extremely promising for biological sensing applications. These devices employ a solid electrolyte as the gate insulator; the very large capacitance of the electrolyte results in low voltage operation and high transconductance or gain. This talk will describe the fabrication of floating gate EGTs and their use as ricin sensors. The critical performance metrics for EGTs compared with other types of TFTs will also be reviewed.

  8. Silicon dioxide with a silicon interfacial layer as an insulating gate for highly stable indium phosphide metal-insulator-semiconductor field effect transistors

    Science.gov (United States)

    Kapoor, V. J.; Shokrani, M.

    1991-01-01

    A novel gate insulator consisting of silicon dioxide (SiO2) with a thin silicon (Si) interfacial layer has been investigated for high-power microwave indium phosphide (InP) metal-insulator-semiconductor field effect transistors (MISFETs). The role of the silicon interfacial layer on the chemical nature of the SiO2/Si/InP interface was studied by high-resolution X-ray photoelectron spectroscopy. The results indicated that the silicon interfacial layer reacted with the native oxide at the InP surface, thus producing silicon dioxide, while reducing the native oxide which has been shown to be responsible for the instabilities in InP MISFETs. While a 1.2-V hysteresis was present in the capacitance-voltage (C-V) curve of the MIS capacitors with silicon dioxide, less than 0.1 V hysteresis was observed in the C-V curve of the capacitors with the silicon interfacial layer incorporated in the insulator. InP MISFETs fabricated with the silicon dioxide in combination with the silicon interfacial layer exhibited excellent stability with drain current drift of less than 3 percent in 10,000 sec, as compared to 15-18 percent drift in 10,000 sec for devices without the silicon interfacial layer. High-power microwave InP MISFETs with Si/SiO2 gate insulators resulted in an output power density of 1.75 W/mm gate width at 9.7 GHz, with an associated power gain of 2.5 dB and 24 percent power added efficiency.

  9. New gate opening hours

    CERN Multimedia

    GS Department

    2009-01-01

    Please note the new opening hours of the gates as well as the intersites tunnel from the 19 May 2009: GATE A 7h - 19h GATE B 24h/24 GATE C 7h - 9h\t17h - 19h GATE D 8h - 12h\t13h - 16h GATE E 7h - 9h\t17h - 19h Prévessin 24h/24 The intersites tunnel will be opened from 7h30 to 18h non stop. GS-SEM Group Infrastructure and General Services Department

  10. 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

  11. Baseline climatology of extremely high vertical wind shears' values over Europe based on ERA-Interim reanalysis

    Science.gov (United States)

    Palarz, Angelika; Celiński-Mysław, Daniel

    2017-04-01

    The dominant role in the development of deep convection is played by kinematic and thermodynamic conditions, as well as atmospheric circulation, land cover and local relief. Severe thunderstorms are considerably more likely to form in environments with large values of convective available potential energy (CAPE) and significant magnitude of vertical wind shears (VWSs). According to the most recent research, the tropospheric wind shears have an important influence on intensity, longevity and organisation of the primary convective systems - bow echoes, squall lines and supercell thunderstorms. This study, in turn, examines the role of wind structure in controlling the spatial and temporal variability of VWSs over Europe. Considering the importance of the kinematic conditions for the convective systems formation, research is limited exclusively to 0-1 km, 0-3 km and 0-6 km wind shears. In order to compute the VWS' values, the data derived from ERA-Interim reanalysis for the period 1981-2015 was applied. It consisted of U and V wind components with 12-hourly sampling and horizontal resolution of 0.75×0.75°. The VWS' values were calculated as wind difference between two levels - this entails that the hodograph's shape was not considered (e.g. Clark 2013, Pucik et. al 2015). We have analysed both VWS' mean values (MN) and frequency of VWSs exceeding assumed thresholds (FQ). Taking into account previous studies (e.g. Rasmussen & Blanchard 1998, Schneider et al. 2006, Schaumann & Przybylinski 2012), the thresholds for extremely high values of vertical wind shears were set at 10 m/s for 0-1 km shear, 15 m/s for 0-3 km shear and 18 m/s for 0-6 km shear. Both MN and FQ values were characterised by strong temporal variability, as well as significant spatial differentiation over the research area. A clear diurnal cycle was identified in the case of 0-1 km shear, while seasonal variability was typical for 0-3 km and 0-6 km shears. Regardless of the season, 0-1 km shear reached

  12. Implementation of high precision optical and radiometric LRO tracking data in the orbit determination to supplement the baseline S-band tracking

    Science.gov (United States)

    Mao, D.; Torrence, M. H.; Mazarico, E.; Neumann, G. A.; Smith, D. E.; Zuber, M. T.

    2016-12-01

    LRO has been in a polar lunar orbit for 7 year since it was launched in June 2009. Seven instruments are onboard LRO to perform a global and detailed geophysical, geological and geochemical mapping of the Moon, some of which have very high spatial resolution. To take full advantage of the high resolution LRO datasets from these instruments, the spacecraft orbit must be reconstructed precisely. The baseline LRO tracking was the NASA's White Sands station in New Mexico and a commercial network, the Universal Space Network (USN), providing up to 20 hours per day of almost continuous S-band radio frequency link to LRO. The USN stations produce S-band range data with a 0.4 m precision and Doppler data with a 0.8 mm/s precision. Using the S-band tracking data together with the high-resolution gravity field model from the GRAIL mission, definitive LRO orbit solutions are obtained with an accuracy of 10 m in total position and 0.5 m radially. Confirmed by the 0.50-m high-resolution NAC images from the LROC team, these orbits well represent the LRO orbit "truth". In addition to the S-band data, one-way Laser Ranging (LR) to LRO provides a unique LRO optical tracking dataset over 5 years, from June 2009 to September 2014. Ten international satellite laser ranging stations contributed over 4000 hours LR data with the 0.05 - 0.10 m normal point precision. Another set of high precision LRO tracking data is provided by the Deep Space Network (DSN), which produces radiometric tracking data more precise than the USN S-band data. In the last two years of the LRO mission, the temporal coverage of the USN data has decreased significantly. We show that LR and DSN data can be a good supplement to the baseline tracking data for the orbit reconstruction.

  13. Electric field-induced transport modulation in VO2 FETs with high-k oxide/organic parylene-C hybrid gate dielectric

    Science.gov (United States)

    Wei, Tingting; Kanki, Teruo; Fujiwara, Kohei; Chikanari, Masashi; Tanaka, Hidekazu

    2016-02-01

    We report on the observation of reversible and immediate resistance switching by high-k oxide Ta2O5/organic parylene-C hybrid dielectric-gated VO2 thin films. Resistance change ratios at various temperatures in the insulating regime were demonstrated to occur in the vicinity of phase transition temperature. We also found an asymmetric hole-electron carrier modulation related to the suppression of phase transition temperature. The results in this research provide a possibility for clarifying the origin of metal-insulator transition in VO2 through the electrostatic field-induced transport modulation.

  14. Electrical analysis of high dielectric constant insulator and metal gate metal oxide semiconductor capacitors on flexible bulk mono-crystalline silicon

    KAUST Repository

    Ghoneim, Mohamed T.

    2015-06-01

    We report on the electrical study of high dielectric constant insulator and metal gate metal oxide semiconductor capacitors (MOSCAPs) on a flexible ultra-thin (25 μm) silicon fabric which is peeled off using a CMOS compatible process from a standard bulk mono-crystalline silicon substrate. A lifetime projection is extracted using statistical analysis of the ramping voltage (Vramp) breakdown and time dependent dielectric breakdown data. The obtained flexible MOSCAPs operational voltages satisfying the 10 years lifetime benchmark are compared to those of the control MOSCAPs, which are not peeled off from the silicon wafer. © 2014 IEEE.

  15. Extraction of high charge density of states in electrolyte-gated polymer thin-film transistor with temperature-dependent measurements

    Science.gov (United States)

    Lee, Jiyoul

    2016-05-01

    Using temperature-dependent charge transport measurements, we investigated spectral density of states (DOS) in the bandgap of polythiophene thin-films under high carrier densities (Meyer-Neldel rule. The spectral DOS extracted from the electrolyte-gated polymer film lie in the range of 8.0 × 1019 cm-3 eV-1-8.0 × 1021 cm-3 eV-1, which are at least two orders of magnitude larger than the DOS extracted from the same polymer film at relatively low induced carrier densities by general oxide dielectrics.

  16. Electric field-induced transport modulation in VO{sub 2} FETs with high-k oxide/organic parylene-C hybrid gate dielectric

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Tingting [Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Faculty of Science, Kunming University of Science and Technology, Kunming 650093 (China); Kanki, Teruo, E-mail: kanki@sanken.osaka-u.ac.jp, E-mail: h-tanaka@sanken.osaka-u.ac.jp; Chikanari, Masashi; Tanaka, Hidekazu, E-mail: kanki@sanken.osaka-u.ac.jp, E-mail: h-tanaka@sanken.osaka-u.ac.jp [Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Fujiwara, Kohei [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)

    2016-02-01

    We report on the observation of reversible and immediate resistance switching by high-k oxide Ta{sub 2}O{sub 5}/organic parylene-C hybrid dielectric-gated VO{sub 2} thin films. Resistance change ratios at various temperatures in the insulating regime were demonstrated to occur in the vicinity of phase transition temperature. We also found an asymmetric hole-electron carrier modulation related to the suppression of phase transition temperature. The results in this research provide a possibility for clarifying the origin of metal-insulator transition in VO{sub 2} through the electrostatic field-induced transport modulation.

  17. Comparative study of CNT, silicon nanowire and fullerene embedded multilayer high-k gate dielectric MOS memory devices

    Energy Technology Data Exchange (ETDEWEB)

    Sengupta, Amretashis; Sarkar, Chandan Kumar [Department of Electronics and Telecommunication Engineering, Jadavpur University, Kolkata-700 032 (India); Requejo, Felix G, E-mail: amretashis@gmail.com [INIFTA, Departmento de Quimica and Departmento de Fisica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CC/67-1900, La Plata (Argentina)

    2011-10-12

    Here, we present a comparative theoretical study on stacked (multilayer) gate dielectric MOS memory devices, having a metallic/semiconducting carbon nanotube (CNT), silicon nanowire (Si NW) and fullerene (C60) embedded nitride layer acting as a floating gate. Two types of devices, one with HfO{sub 2}-SiO{sub 2} stack (stack-1) and the other with La{sub 2}O{sub 3}-SiO{sub 2} stack (stack-2) as the tunnel oxide were compared. We evaluated the effective barrier height, the dielectric constant and the effective electron mobility in the composite gate dielectric with the Maxwell-Garnett effective medium theory. Thereafter applying the WKB approximation, we simulated the Fowler-Nordheim (F-N) tunnelling/writing current and the direct tunnelling/leakage current in these devices. We evaluated the I-V characteristics, the charge decay and also the impact of CNT/Si NW aspect ratio and the volume fraction on the effective barrier height and the write voltage, respectively. We also simulated the write time, retention time and the erase time of these MOS devices. Based on the simulation results, it was concluded that the metallic CNT embedded stack-1 device offered the best performance in terms of higher F-N tunnelling current, lower direct tunnelling current and lesser write voltage and write time compared with the other devices. In case of direct tunnelling leakage and retention time it was found that the met CNT embedded stack-2 device showed better characteristics. For erasing, however, the C60 embedded stack-1 device showed the smallest erase time. When compared with earlier reports, it was seen that CNT, C60 and Si NW embedded devices all performed better than nanocrystalline Si embedded MOS non-volatile memories.

  18. Precursor- route ZnO films from mixed casting solvent for high performance aqueous electrolyte- gated transistors

    OpenAIRE

    Grell, M.; Althagafi, T.M.; Algarni, S.A.; Al Naim, A.; Mazher, J.

    2015-01-01

    We significantly improved the properties of semiconducting zinc oxide (ZnO) films resulting from the thermal conversion of a soluble precursor, zinc acetate (ZnAc), by using a mixed casting solvent for the precursor. ZnAc dissolves more readily in a 1:1 mix of ethanol (EtOH) and acetone than in either pure EtOH, pure acetone, or pure isopropanol, and ZnO films converted from mixed solvent cast ZnAc are more homogeneous. When gated with a biocompatible electrolyte, phosphate buffered saline (P...

  19. Fusion of space-borne multi-baseline and multi-frequency interferometric results based on extended Kalman filter to generate high quality DEMs

    Science.gov (United States)

    Zhang, Xiaojie; Zeng, Qiming; Jiao, Jian; Zhang, Jingfa

    2016-01-01

    Repeat-pass Interferometric Synthetic Aperture Radar (InSAR) is a technique that can be used to generate DEMs. But the accuracy of InSAR is greatly limited by geometrical distortions, atmospheric effect, and decorrelations, particularly in mountainous areas, such as western China where no high quality DEM has so far been accomplished. Since each of InSAR DEMs generated using data of different frequencies and baselines has their own advantages and disadvantages, it is therefore very potential to overcome some of the limitations of InSAR by fusing Multi-baseline and Multi-frequency Interferometric Results (MMIRs). This paper proposed a fusion method based on Extended Kalman Filter (EKF), which takes the InSAR-derived DEMs as states in prediction step and the flattened interferograms as observations in control step to generate the final fused DEM. Before the fusion, detection of layover and shadow regions, low-coherence regions and regions with large height error is carried out because MMIRs in these regions are believed to be unreliable and thereafter are excluded. The whole processing flow is tested with TerraSAR-X and Envisat ASAR datasets. Finally, the fused DEM is validated with ASTER GDEM and national standard DEM of China. The results demonstrate that the proposed method is effective even in low coherence areas.

  20. High-frequency detection of cell activity of Physarum polycephalum by a planar open gate AlGaN/GaN HEMT

    Science.gov (United States)

    Witte, Hartmut; Lippelt, Thomas; Warnke, Christian; Dadgar, Armin; Hauser, Marcus J. B.; Krost, Alois

    2014-10-01

    The dynamics of cells of the slime mould Physarum polycephalum are investigated with a planar AlGaN/GaN high electron mobility transistor (HEMT) without any gate metallization. The source-drain contacts are used in a two-electrode arrangement whereas the free gate surface area is occupied by the Physarum cell. In order to understand the measured signals, basic properties of the interface between the cell and the HEMT surface were analysed by impedance spectroscopy. At high frequencies the interface impedance is governed by the conductance of the cell due to a direct current through the HEMT/cell interface. The locomotive dynamics of Physarum were recorded by the source-drain impedance at 10 kHz in combination with simultaneous video imaging that monitored the degree of occupancy of the HEMT surface by the cell. A precise correlation was found between the impedance and the coverage of the HEMT surface by the cell. It is observed that the entire region between the contacts is sensitive to the cell activity. Well-resolved cellular oscillations were observed for all measured parameters. Their periods corresponded to the typical periods of the intracellular shuttle streaming of protoplasma in Physarum. This demonstrates that high-frequency impedance measurements with AlGaN/GaN HEMT structures are well suited for the analysis of both the static parts of single Physarum cells as well as of their dynamic behaviour, such as their expansion and motility.

  1. GaN-Based High-k Praseodymium Oxide Gate MISFETs with P2S5/(NH42SX + UV Interface Treatment Technology

    Directory of Open Access Journals (Sweden)

    Chao-Wei Lin

    2012-01-01

    Full Text Available This study examines the praseodymium-oxide- (Pr2O3- passivated AlGaN/GaN metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs with high dielectric constant in which the AlGaN Schottky layers are treated with P2S5/(NH42SX + ultraviolet (UV illumination. An electron-beam evaporated Pr2O3 insulator is used instead of traditional plasma-assisted chemical vapor deposition (PECVD, in order to prevent plasma-induced damage to the AlGaN. In this work, the HEMTs are pretreated with P2S5/(NH42SX solution and UV illumination before the gate insulator (Pr2O3 is deposited. Since stable sulfur that is bound to the Ga species can be obtained easily and surface oxygen atoms are reduced by the P2S5/(NH42SX pretreatment, the lowest leakage current is observed in MIS-HEMT. Additionally, a low flicker noise and a low surface roughness (0.38 nm are also obtained using this novel process, which demonstrates its ability to reduce the surface states. Low gate leakage current Pr2O3 and high-k AlGaN/GaN MIS-HEMTs, with P2S5/(NH42SX + UV illumination treatment, are suited to low-noise applications, because of the electron-beam-evaporated insulator and the new chemical pretreatment.

  2. High-temperature studies of multiple fluorinated traps within an Al2O3 gate dielectric for E-Mode AlGaN/GaN power MIS-HEMTs

    Science.gov (United States)

    Wang, Yun-Hsiang; Liang, Yung C.; Samudra, Ganesh S.; Chu, Po-Ju; Liao, Ya-Chu; Huang, Chih-Fang; Kuo, Wei-Hung; Lo, Guo-Qiang

    2016-02-01

    Normally-off AlGaN/GaN MIS-HEMT devices with multiple fluorinated ALD-Al2O3 layers as the gate dielectric have been reported to achieve a high threshold voltage for normally-off operations with satisfactory performance for both on and off states at room temperature. However, a large swing in gate threshold voltage is found when devices operate at elevated temperatures. Hence, further study of the gate dielectric on the distribution of fluorinated trap states in the energy band are required to assess the gate function at higher temperatures. Through the use of the charge analytical model and Poole-Frenkel trap emission theory, the gate voltage stressing measurement was carried out to accurately find the effective trap state distribution within the Al2O3 energy bandgap created by fluorinated treatments. For the samples fabricated and used in the investigation, we found that a higher population of fluorinated trap states located deeper than 1.1 eV corresponding to emission levels above 200 °C would allow more trapped charges to remain in the dielectric at high temperature for better threshold voltage retention. We also discovered that a higher fluorine treatment power on the gate dielectric could yield a higher trap state density at deeper levels, resulting in better temperature stability.

  3. 2 MeV electron irradiation effects on bulk and interface of atomic layer deposited high-k gate dielectrics on silicon

    Energy Technology Data Exchange (ETDEWEB)

    García, H., E-mail: hecgar@ele.uva.es [Departamento de Electricidad y Electrónica, ETSI Telecomunicación, Universidad de Valladolid, 47011 Valladolid (Spain); Castán, H.; Dueñas, S.; Bailón, L. [Departamento de Electricidad y Electrónica, ETSI Telecomunicación, Universidad de Valladolid, 47011 Valladolid (Spain); Campabadal, F.; Rafí, J.M.; Zabala, M.; Beldarrain, O. [Institut de Microelectrònica de Barcelona (IMB-CNM), CSIC, Campus UAB, 08193 Bellaterra (Spain); Ohyama, H.; Takakura, K.; Tsunoda, I. [Department of Electronic Engineering, Kumamoto National College of Technology, Kumamoto 861-1102 (Japan)

    2013-05-01

    2 MeV electron irradiation effects on the electrical properties of Al{sub 2}O{sub 3} and HfO{sub 2}-based metal–insulator–semiconductor capacitors have been studied. High-k dielectrics were directly grown on silicon by atomic layer deposition. Capacitors were exposed to three different electron irradiation doses of 0.025, 0.25 and 2.5 MGy. Capacitance–voltage, deep-level transient spectroscopy, conductance transients, flat-band voltage transients and current–voltage techniques were used to characterize the defects induced or activated by irradiation on the dielectric bulk and on the interface with silicon substrate. In all cases, positive charge is trapped in the dielectric bulk after irradiation indicating the existence of hole traps in the dielectric. When the samples are exposed to 2 MeV electron beam (e-beam) irradiation, electron–hole pairs are created and holes are then captured by the hole traps. Insulator/semiconductor interface quality slightly improves for low irradiation doses, but it is degraded for high doses. Irradiation always degrades the dielectric layers in terms of gate leakage current: the trapped holes are mobile charge which can contribute to leakage current by hopping from trap to trap. - Highlights: ► Positive charge accumulates inside dielectrics after electron irradiation. ► Irradiation improves oxide/semiconductor interface for low doses. ► Irradiation increases gate leakage current.

  4. Effects of Gate Stack Structural and Process Defectivity on High-k Dielectric Dependence of NBTI Reliability in 32 nm Technology Node PMOSFETs

    Directory of Open Access Journals (Sweden)

    H. Hussin

    2014-01-01

    Full Text Available We present a simulation study on negative bias temperature instability (NBTI induced hole trapping in E′ center defects, which leads to depassivation of interface trap precursor in different geometrical structures of high-k PMOSFET gate stacks using the two-stage NBTI model. The resulting degradation is characterized based on the time evolution of the interface and hole trap densities, as well as the resulting threshold voltage shift. By varying the physical thicknesses of the interface silicon dioxide (SiO2 and hafnium oxide (HfO2 layers, we investigate how the variation in thickness affects hole trapping/detrapping at different stress temperatures. The results suggest that the degradations are highly dependent on the physical gate stack parameters for a given stress voltage and temperature. The degradation is more pronounced by 5% when the thicknesses of HfO2 are increased but is reduced by 11% when the SiO2 interface layer thickness is increased during lower stress voltage. However, at higher stress voltage, greater degradation is observed for a thicker SiO2 interface layer. In addition, the existence of different stress temperatures at which the degradation behavior differs implies that the hole trapping/detrapping event is thermally activated.

  5. Recessed-gate quasi-enhancement-mode AlGaN/GaN high electron mobility transistors with oxygen plasma treatment

    Science.gov (United States)

    He, Yun-Long; Wang, Chong; Mi, Min-Han; Zheng, Xue-Feng; Zhang, Meng; Zhao, Meng-Di; Zhang, Heng-Shuang; Chen, Li-Xiang; Zhang, Jin-Cheng; Ma, Xiao-Hua; Hao, Yue

    2016-11-01

    In this paper, the enhancement-mode AlGaN/GaN HEMT combined with the low damage recessed-gate etching and the optimized oxygen plasma treatment was fabricated. Scanning electron microscope/energy dispersive spectrometer (SEM/EDS) method and x-ray photoelectron spectroscopy (XPS) method were used to confirm the formation of oxides. Based on the experimental results, the obtained enhancement-mode HEMT exhibited a threshold voltage of 0.5 V, a high peak transconductance of 210 mS/mm, and a maximum drain current of 610 mA/mm at the gate bias of 4 V. Meanwhile, the on/off current ratio of enhancement-mode HEMT was as high as 108, drain induced barrier lowering (DIBL) was as low as 5 mV/V, and subthreshold swing (SS) of 80 mV/decade was obtained. Compared with the conventional HEMT, the Schottky reverse current of enhancement-mode HEMT was three orders of magnitude lower, and the off-state breakdown voltage of which was higher. In addition, a power gain cutoff frequency (f max) of the enhancement-mode HEMT was larger than that of the conventional one. Project supported by the National Natural Science Foundation of China (Grant Nos. 61574110, 61334002, and 61474091) and the National Key Technology Research and Development Program of the Ministry of Science and Technology of China (Grant No. 2015AA016801).

  6. 晶闸管强触发电路设计%Design of High Current Gate Circuit of Thyristor Based on MOSFET

    Institute of Scientific and Technical Information of China (English)

    郭帆; 王海洋; 何小平; 周竞之

    2012-01-01

    In order to study the characteristics of thyristor, basing on MOSFET with fast switching and high pulsed current, high current gate circuit of thyristor has been designed. Peak gate current is varied from 0.35 -39.6 A, leading edge from 35 ~540 ns and di/dt from 3.4 ~83. 3 A/us. Results indicate that the circuit is stable and reliable for triggering thyristor and the jitter of pulsed current is less than 4 ns.%为了研究晶闸管在强触发下的导通特性,利用功率MOSFET的快开通特性和通流能力,设计了光纤控制晶闸管强触发电路.该电路中晶闸管门极触发电流峰值范围为0.35~39.6 A,前沿范围为35~540ns,电流上升率范围为3.4~83.3 A/μs.实验结果表明,该电路参数调节范围宽,触发电流抖动小(小于4ns),具有较高的稳定性和可靠性.

  7. The combination of amlodipine and angiotensin receptor blocker or diuretics in high-risk hypertensive patients: rationale, design and baseline characteristics

    Science.gov (United States)

    Wang, W; Ma, L; Zhang, Y; Deng, Q; Liu, M; Liu, L

    2011-01-01

    The Chinese Hypertension Intervention Efficacy Study (CHIEF) is a multi-centre randomized controlled clinical trial comparing the effects of amlodipine+angiotensin II receptor blocker and amlodipine+diuretics on the incidence of cardiovascular events, represented as a composite of non-fatal stroke, non-fatal myocardial infarction and cardiovascular death events in high-risk Chinese hypertensive patients. The study also evaluates the long-term effects of lipid-lowering treatment and lifestyle modification. From October 2007 to October 2008, 13 542 patients were enrolled into the study in 180 centres in China. Patients will be followed up for 4 years. There was no difference in baseline characteristics between the two blood pressure arms. PMID:20445570

  8. Growth Related Carrier Mobility Enhancement of Pentacene Thin-Film Transistors with High-k Oxide Gate Dielectric

    Institute of Scientific and Technical Information of China (English)

    YU Ai-Fang; QI Qiong; JIANG Peng; JIANG Chao

    2009-01-01

    Carrier mobifity enhancement from 0.09 to 0.59cm2/Vs is achieved for pentacene-based thin-film transistors (TFTs) by modifying the HfO2 gate dielectric with a polystyrene (PS) thin film. The improvement of the transistor's performance is found to be strongly related to the initial film morphologies of pentacene on the dielectrics. In contrast to the three-dimensional island-like growth mode on the HfO2 surface, the Stranski-Krastanov growth mode on the smooth and nonpolar PS/HfO2 surface is believed to be the origin of the excellent carrier mobifity of the TFTs. A large well-connected first monolayer with fewer boundaries is formed via the Stranski-Krastanov growth mode, which facilitates a charge transport parallel to the substrate and promotes higher carrier mobility.

  9. Low-voltage back-gated atmospheric pressure chemical vapor deposition based graphene-striped channel transistor with high-κ dielectric showing room-temperature mobility > 11,000 cm(2)/V·s.

    Science.gov (United States)

    Smith, Casey; Qaisi, Ramy; Liu, Zhihong; Yu, Qingkai; Hussain, Muhammad Mustafa

    2013-07-23

    Utilization of graphene may help realize innovative low-power replacements for III-V materials based high electron mobility transistors while extending operational frequencies closer to the THz regime for superior wireless communications, imaging, and other novel applications. Device architectures explored to date suffer a fundamental performance roadblock due to lack of compatible deposition techniques for nanometer-scale dielectrics required to efficiently modulate graphene transconductance (gm) while maintaining low gate capacitance-voltage product (CgsVgs). Here we show integration of a scaled (10 nm) highgate dielectric aluminum oxide (Al2O3) with an atmospheric pressure chemical vapor deposition (APCVD)-derived graphene channel composed of multiple 0.25 μm stripes to repeatedly realize room-temperature mobility of 11,000 cm(2)/V·s or higher. This high performance is attributed to the APCVD graphene growth quality, excellent interfacial properties of the gate dielectric, conductivity enhancement in the graphene stripes due to low tox/Wgraphene ratio, and scaled high-κ dielectric gate modulation of carrier density allowing full actuation of the device with only ±1 V applied bias. The superior drive current and conductance at Vdd = 1 V compared to other top-gated devices requiring undesirable seed (such as aluminum and poly vinyl alcohol)-assisted dielectric deposition, bottom gate devices requiring excessive gate voltage for actuation, or monolithic (nonstriped) channels suggest that this facile transistor structure provides critical insight toward future device design and process integration to maximize CVD-based graphene transistor performance.

  10. Low-voltage back-gated atmospheric pressure chemical vapor deposition based graphene-striped channel transistor with high-κ dielectric showing room-temperature mobility > 11 000 cm2/V·s

    KAUST Repository

    Smith, Casey

    2013-07-23

    Utilization of graphene may help realize innovative low-power replacements for III-V materials based high electron mobility transistors while extending operational frequencies closer to the THz regime for superior wireless communications, imaging, and other novel applications. Device architectures explored to date suffer a fundamental performance roadblock due to lack of compatible deposition techniques for nanometer-scale dielectrics required to efficiently modulate graphene transconductance (gm) while maintaining low gate capacitance-voltage product (CgsVgs). Here we show integration of a scaled (10 nm) highgate dielectric aluminum oxide (Al2O3) with an atmospheric pressure chemical vapor deposition (APCVD)-derived graphene channel composed of multiple 0.25 μm stripes to repeatedly realize room-temperature mobility of 11 000 cm 2/V·s or higher. This high performance is attributed to the APCVD graphene growth quality, excellent interfacial properties of the gate dielectric, conductivity enhancement in the graphene stripes due to low t ox/Wgraphene ratio, and scaled high-κ dielectric gate modulation of carrier density allowing full actuation of the device with only ±1 V applied bias. The superior drive current and conductance at Vdd = 1 V compared to other top-gated devices requiring undesirable seed (such as aluminum and poly vinyl alcohol)-assisted dielectric deposition, bottom gate devices requiring excessive gate voltage for actuation, or monolithic (nonstriped) channels suggest that this facile transistor structure provides critical insight toward future device design and process integration to maximize CVD-based graphene transistor performance. © 2013 American Chemical Society.

  11. Performance Evaluation of an Automotive-Grade, High Speed Gate Driver for SiC FETs, Type UCC27531, Over a Wide Temperature Range

    Science.gov (United States)

    Boomer, Kristen; Hammoud, Ahmad

    2015-01-01

    Silicon carbide (SiC) devices are becoming widely used in electronic power circuits as replacement for conventional silicon parts due to their attractive properties that include low on-state resistance, high temperature tolerance, and high frequency operation. These attributes have a significant impact by reducing system weight, saving board space, and conserving power. In this work, the performance of an automotive-grade high speed gate driver with potential use in controlling SiC FETs (field-Effect Transistors) in converters or motor control applications was evaluated under extreme temperatures and thermal cycling. The investigations were carried out to assess performance and to determine suitability of this device for use in space exploration missions under extreme temperature conditions.

  12. A high-speed two-frame, 1-2 ns gated X-ray CMOS imager used as a hohlraum diagnostic on the National Ignition Facility (invited)

    Science.gov (United States)

    Chen, Hui; Palmer, N.; Dayton, M.; Carpenter, A.; Schneider, M. B.; Bell, P. M.; Bradley, D. K.; Claus, L. D.; Fang, L.; Hilsabeck, T.; Hohenberger, M.; Jones, O. S.; Kilkenny, J. D.; Kimmel, M. W.; Robertson, G.; Rochau, G.; Sanchez, M. O.; Stahoviak, J. W.; Trotter, D. C.; Porter, J. L.

    2016-11-01

    A novel x-ray imager, which takes time-resolved gated images along a single line-of-sight, has been successfully implemented at the National Ignition Facility (NIF). This Gated Laser Entrance Hole diagnostic, G-LEH, incorporates a high-speed multi-frame CMOS x-ray imager developed by Sandia National Laboratories to upgrade the existing Static X-ray Imager diagnostic at NIF. The new diagnostic is capable of capturing two laser-entrance-hole images per shot on its 1024 × 448 pixels photo-detector array, with integration times as short as 1.6 ns per frame. Since its implementation on NIF, the G-LEH diagnostic has successfully acquired images from various experimental campaigns, providing critical new information for understanding the hohlraum performance in inertial confinement fusion (ICF) experiments, such as the size of the laser entrance hole vs. time, the growth of the laser-heated gold plasma bubble, the change in brightness of inner beam spots due to time-varying cross beam energy transfer, and plasma instability growth near the hohlraum wall.

  13. AlGaN/GaN Metal-Oxide-Semiconductor High-Electron-Mobility Transistor with Polarized P(VDF-TrFE) Ferroelectric Polymer Gating

    Science.gov (United States)

    Liu, Xinke; Lu, Youming; Yu, Wenjie; Wu, Jing; He, Jiazhu; Tang, Dan; Liu, Zhihong; Somasuntharam, Pannirselvam; Zhu, Deliang; Liu, Wenjun; Cao, Peijiang; Han, Sun; Chen, Shaojun; Seow Tan, Leng

    2015-01-01

    Effect of a polarized P(VDF-TrFE) ferroelectric polymer gating on AlGaN/GaN metal-oxide-semiconductor high-electron-mobility transistors (MOS-HEMTs) was investigated. The P(VDF-TrFE) gating in the source/drain access regions of AlGaN/GaN MOS-HEMTs was positively polarized (i.e., partially positively charged hydrogen were aligned to the AlGaN surface) by an applied electric field, resulting in a shift-down of the conduction band at the AlGaN/GaN interface. This increases the 2-dimensional electron gas (2-DEG) density in the source/drain access region of the AlGaN/GaN heterostructure, and thereby reduces the source/drain series resistance. Detailed material characterization of the P(VDF-TrFE) ferroelectric film was also carried out using the atomic force microscopy (AFM), X-ray Diffraction (XRD), and ferroelectric hysteresis loop measurement. PMID:26364872

  14. Electrical characteristics of polycrystalline Si layers embedded into high-k Al{sub 2}O{sub 3} gate layers

    Energy Technology Data Exchange (ETDEWEB)

    Park, Byoungjun; Cho, Kyoungah [Department of Electrical Engineering and Institute of Nano Science, Korea University, Seoul 136-701 (Korea, Republic of); Kim, Sangsig [Department of Electrical Engineering and Institute of Nano Science, Korea University, Seoul 136-701 (Korea, Republic of)], E-mail: sangsig@korea.ac.kr

    2008-09-30

    The electrical characteristics of polycrystalline Si (poly Si) layers embedded into high-k Al{sub 2}O{sub 3} (alumina) gate layers are investigated in this work. The capacitance versus voltage (C-V) curves obtained from the metal-alumina-polysilicon-alumina-silicon (MASAS) capacitors exhibit significant threshold voltage shifts, and the width of their hysteresis window is dependent on the range of the voltage sweep. The counterclockwise hysteresis observed in the C-V curves indicates that electrons originating from the p-type Si substrate in the inversion condition are trapped in the floating gate layer consisting of the poly Si layer present between the top and bottom Al{sub 2}O{sub 3} layers in the MASAS capacitor. Also, current versus voltage (I-V) measurements are performed to examine the electrical characteristics of the fabricated capacitors. The I-V measurements reveal that our MASAS capacitors show a very low leakage current density, compared to the previously reported results.

  15. The Effect of Prophylactic Lamivudine plus Adefovir Therapy Compared with Lamivudine Alone in Preventing Hepatitis B Reactivation in Lymphoma Patients with High Baseline HBV DNA during Chemotherapy.

    Science.gov (United States)

    Cai, Qingqing; Chen, Kailin; Chen, Jie; Wu, Shaoxu; Geng, Qirong; Huang, Huiqiang; Lin, Tongyu; Jiang, Wenqi; Xia, Zhongjun; Duan, Huaxin; Rao, Huilan; Yao, Mengfei; Hu, Liyang

    2016-01-01

    Prophylactic antiviral therapy is essential for lymphoma patients with high baseline HBV DNA who undergo cytotoxic chemotherapy. However, there are limited data on the optimal options. The present study was designed to compare the efficacy of prophylactic lamivudine (LAM) with lamivudine plus adefovir dipivoxil (LAM+ADV) in preventing hepatitis B virus (HBV) reactivation in lymphoma with, pre-chemotherapy HBV DNA load ≥2000 IU/ml. We retrospectively analyzed the medical records of 86 lymphoma patients with baseline HBV DNA load ≥2000 IU/ml during chemotherapy and received LAM or LAM+ADV as prophylaxis between January 1, 2008 and November 30, 2014 at Sun Yat-sen University Cancer Center, China. Sixty-five patients received LAM and 21 received LAM+ADV. The rate was significantly lower in the LAM+ADV group compared with the LAM group for HBV reactivation (23.8% vs 55.4%; p = 0.012), while no difference was observed between the two groups in patients for HBV-related hepatitis (21.3% vs 33.3%; p   =  0.349), and chemotherapy disruption (10.9% vs 19.0%; p = 0.337). In a multivariate analysis of factors associated with HBV reactivation in these patients, LAM+ADV treatment and HBeAg negative were the independent protective factors. Therefore, LAM+ADV should be considered for antiviral prophylaxis in lymphoma patients with pre-chemotherapy HBV DNA load ≥2000 IU/ml. Further study is warranted to confirm these findings.

  16. Series resistance effect on time zero dielectrics breakdown characteristics of MOSCAP with ultra-thin EOT high-k/metal gate stacks

    Science.gov (United States)

    Hao, Xu; Hong, Yang; Yanrong, Wang; Wenwu, Wang; Guangxing, Wan; Shangqing, Ren; Weichun, Luo; Luwei, Qi; Chao, Zhao; Dapeng, Chen; Xinyu, Liu; Tianchun, Ye

    2016-05-01

    The time zero dielectric breakdown characteristics of MOSCAP with ultra-thin EOT high-k metal gate stacks are studied. The TZDB results show an abnormal area dependence due to the series resistance effect. The series resistance components extracted from the Fowler-Nordheim tunneling relation are attributed to the spreading resistance due to the asymmetry electrodes. Based on a series model to eliminate the series resistance effect, an area acceleration dependence is obtained by correcting the TZDB results. The area dependence follows Poisson area scaling rules, which indicates that the mechanism of TZDB is the same as TDDB and could be considered as a trap generation process. Project supported by the National High Technology Research and Development Program (863 Program) of China (No. SS2015AA010601), the National Natural Science Foundation of China (Nos. 61176091, 61306129), and the Opening Project of the Key Laboratory of Microelectronics Devices & Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences.

  17. Structural and electrical characteristics of high-k/metal gate metal oxide semiconductor capacitors fabricated on flexible, semi-transparent silicon (100) fabric

    KAUST Repository

    Rojas, Jhonathan Prieto

    2013-02-12

    In pursuit of flexible computers with high performance devices, we demonstrate a generic process to fabricate 10 000 metal-oxide-semiconductor capacitors (MOSCAPs) with semiconductor industry\\'s most advanced high-k/metal gate stacks on widely used, inexpensive bulk silicon (100) wafers and then using a combination of iso-/anisotropic etching to release the top portion of the silicon with the already fabricated devices as a mechanically flexible (bending curvature of 133 m−1), optically semi-transparent silicon fabric (1.5 cm × 3 cm × 25 μm). The electrical characteristics show 3.7 nm effective oxide thickness, −0.2 V flat band voltage, and no hysteresis from the fabricated MOSCAPs.

  18. High-k gate stacks on low bandgap tensile strained Ge and GeSn alloys for field-effect transistors.

    Science.gov (United States)

    Wirths, Stephan; Stange, Daniela; Pampillón, Maria-Angela; Tiedemann, Andreas T; Mussler, Gregor; Fox, Alfred; Breuer, Uwe; Baert, Bruno; San Andrés, Enrique; Nguyen, Ngoc D; Hartmann, Jean-Michel; Ikonic, Zoran; Mantl, Siegfried; Buca, Dan

    2015-01-14

    We present the epitaxial growth of Ge and Ge0.94Sn0.06 layers with 1.4% and 0.4% tensile strain, respectively, by reduced pressure chemical vapor deposition on relaxed GeSn buffers and the formation of high-k/metal gate stacks thereon. Annealing experiments reveal that process temperatures are limited to 350 °C to avoid Sn diffusion. Particular emphasis is placed on the electrical characterization of various high-k dielectrics, as 5 nm Al2O3, 5 nm HfO2, or 1 nmAl2O3/4 nm HfO2, on strained Ge and strained Ge0.94Sn0.06. Experimental capacitance-voltage characteristics are presented and the effect of the small bandgap, like strong response of minority carriers at applied field, are discussed via simulations.

  19. AlGaN/GaN high-electron-mobility transistor with distributed gate grown on stripe-patterned Si(111) substrate

    Science.gov (United States)

    Lin, Jyun-Hao; Huang, Shyh-Jer; Lai, Chao-Hsing; Su, Yan-Kuin

    2016-01-01

    We have successfully fabricated an AlGaN/GaN high-electron-mobility transistor with a distributed gate (DG-HEMT) on a stripe-patterned Si substrate. With the help of the stripe pattern, GaN film with low defect density could be deposited by two-step growth. The striped AlGaN/GaN structure could be obtained naturally by stopping the epitaxy process before coalescence. The DG-HEMT fabricated on the striped pattern layout shows good performance. The output characteristics were enhanced from 297 to 337 mA/mm, because the high quality of GaN grown on the patterned substrate can reduce the number of defects. In addition, the drain current was not decreased because the heat problem was reduced in the DG structure.

  20. High performing solution-coated electrolyte-gated organic field-effect transistors for aqueous media operation

    Science.gov (United States)

    Zhang, Qiaoming; Leonardi, Francesca; Casalini, Stefano; Temiño, Inés; Mas-Torrent, Marta

    2016-12-01

    Since the first demonstration, the electrolyte-gated organic field-effect transistors (EGOFETs) have immediately gained much attention for the development of cutting-edge technology and they are expected to have a strong impact in the field of (bio-)sensors. However EGOFETs directly expose their active material towards the aqueous media, hence a limited library of organic semiconductors is actually suitable. By using two mostly unexplored strategies in EGOFETs such as blended materials together with a printing technique, we have successfully widened this library. Our benchmarks were 6,13-bis(triisopropylsilylethynyl)pentacene and 2,8-difluoro-5,11-bis(triethylsilylethynyl)anthradithiophene (diF-TES-ADT), which have been firstly blended with polystyrene and secondly deposited by means of the bar-assisted meniscus shearing (BAMS) technique. Our approach yielded thin films (i.e. no thicker than 30 nm) suitable for organic electronics and stable in liquid environment. Up to date, these EGOFETs show unprecedented performances. Furthermore, an extremely harsh environment, like NaCl 1M, has been used in order to test the limit of operability of these electronic devices. Albeit an electrical worsening is observed, our devices can operate under different electrical stresses within the time frame of hours up to a week. In conclusion, our approach turns out to be a powerful tool for the EGOFET manufacturing.

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

    Science.gov (United States)

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

    2016-05-01

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

  2. Improved Classical Simulation of Quantum Circuits Dominated by Clifford Gates.

    Science.gov (United States)

    Bravyi, Sergey; Gosset, David

    2016-06-24

    We present a new algorithm for classical simulation of quantum circuits over the Clifford+T gate set. The runtime of the algorithm is polynomial in the number of qubits and the number of Clifford gates in the circuit but exponential in the number of T gates. The exponential scaling is sufficiently mild that the algorithm can be used in practice to simulate medium-sized quantum circuits dominated by Clifford gates. The first demonstrations of fault-tolerant quantum circuits based on 2D topological codes are likely to be dominated by Clifford gates due to a high implementation cost associated with logical T gates. Thus our algorithm may serve as a verification tool for near-term quantum computers which cannot in practice be simulated by other means. To demonstrate the power of the new method, we performed a classical simulation of a hidden shift quantum algorithm with 40 qubits, a few hundred Clifford gates, and nearly 50 T gates.

  3. Glare suppression by coherence gated negation

    CERN Document Server

    Zhou, Edward Haojiang; Brake, Joshua; Ruan, Haowen; Yang, Changhuei

    2016-01-01

    Imaging of a weak target hidden behind a scattering medium can be significantly confounded by glare. We report a method, termed coherence gated negation (CGN), that uses destructive optical interference to suppress glare and allow improved imaging of a weak target. As a demonstration, we show that by permuting through a set range of amplitude and phase values for a reference beam interfering with the optical field from the glare and target reflection, we can suppress glare by an order of magnitude, even when the optical wavefront is highly disordered. This strategy significantly departs from conventional coherence gating methods in that CGN actively 'gates out' the unwanted optical contributions while conventional methods 'gate in' the target optical signal. We further show that the CGN method can outperform conventional coherence gating image quality in certain scenarios by more effectively rejecting unwanted optical contributions.

  4. Ultrahigh sensitive sub-terahertz detection by InP-based asymmetric dual-grating-gate high-electron-mobility transistors and their broadband characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Kurita, Y.; Satou, A., E-mail: a-satou@riec.tohoku.ac.jp; Kobayashi, K.; Boubanga Tombet, S.; Suemitsu, T.; Otsuji, T. [Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Ducournau, G. [Institut d' Electronique, de Microélectronique et de Nanotechnologie, 59562 Villeneuve d' Ascq Cedex (France); Coquillat, D.; Knap, W. [Laboratoire Charles Coulomb, UMR 5221, Université Montpellier 2 - CNRS, F-34095 Montpellier (France); Meziani, Y. M. [Departamento de Fisica Aplicada, Universidad de Salamanca, Salamanca 37008 (Spain); Popov, V. V. [Kotelnikov Institute of Radio Engineering and Electronics, 410019 Saratov (Russian Federation)

    2014-06-23

    We report on room-temperature plasmonic detection of sub-terahertz radiation by InAlAs/InGaAs/InP high electron mobility transistors with an asymmetric dual-grating-gate structure. Maximum responsivities of 22.7 kV/W at 200 GHz and 21.5 kV/W at 292 GHz were achieved under unbiased drain-to-source condition. The minimum noise equivalent power was estimated to be 0.48 pW/Hz{sup 0.5} at 200 GHz at room temperature, which is the record-breaking value ever reported for plasmonic THz detectors. Frequency dependence of the responsivity in the frequency range of 0.2–2 THz is in good agreement with the theory.

  5. Improved thermal stability and electrical properties of atomic layer deposited HfO{sub 2}/AlN high-k gate dielectric stacks on GaAs

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Yan-Qiang; Li, Xin; Zhu, Lin; Cao, Zheng-Yi; Wu, Di; Li, Ai-Dong, E-mail: adli@nju.edu.cn [National Laboratory of Solid State Microstructures and Department of Materials Science and Engineering, College of Engineering and Applied sciences, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093 (China)

    2015-01-15

    The thermal stability and electrical properties of atomic layer deposited HfO{sub 2}/AlN high-k gate dielectric stacks on GaAs were investigated. Compared to HfO{sub 2}/Al{sub 2}O{sub 3} gate dielectric, significant improvements in interfacial quality as well as electrical characteristics after postdeposition annealing are confirmed by constructing HfO{sub 2}/AlN dielectric stacks. The chemical states were carefully explored by the x-ray photoelectron spectroscopy, which indicates the AlN layers effectively prevent from the formation of defective native oxides at elevated temperatures. In addition, it is found that NH{sub 3} plasma during AlN plasma-enhanced atomic layer deposition also has the self-cleaning effect as Al(CH{sub 3}){sub 3} in removing native oxides. The passivating AlN layers suppress the formation of interfacial oxide and trap charge, leading to the decrease of capacitance equivalent thickness after annealing. Moreover, HfO{sub 2}/AlN/GaAs sample has a much lower leakage current density of 2.23 × 10{sup −4} A/cm{sup 2} than HfO{sub 2}/Al{sub 2}O{sub 3}/GaAs sample of 2.58 × 10{sup −2} A/cm{sup 2}. For the HfO{sub 2}/AlN/GaAs sample annealed at 500 °C, it has a lowest interface trap density value of 2.11 × 10{sup 11} eV{sup −1} cm{sup −2}. These results indicate that adopting HfO{sub 2}/AlN dielectric stacks may be a promising approach for the realization of high quality GaAs-based transistor devices.

  6. Effects of chronic treatment with the eNOS stimulator Impaza on penis length and sexual behaviors in rats with a high baseline of sexual activity.

    Science.gov (United States)

    Chu, X; Zhavbert, E S; Dugina, J L; Kheyfets, I A; Sergeeva, S A; Epstein, O I; Agmo, A

    2014-01-01

    Endothelial nitric oxide synthase (eNOS) has an important role in erection, and it also affects aspects of sexual behavior. In this experiment, we determined whether a compound enhancing the activity of eNOS, Impaza, could stimulate any aspect of sexual behavior and increase penis length in rats with a high baseline of sexual activity. For comparison, the PDE5 inhibitor sildenafil was included. Male rats were orally treated with Impaza or sildenafil for 28 days. Impaza (3 ml kg(-1)) was given daily while sildenafil (3 mg kg(-1)) was given twice weekly. Tests for sexual incentive motivation and copulatory behavior were performed just before drug treatment and at days 7, 14 and 28 of treatment. In addition, the length of the protruding penis at mount, intromission and ejaculation was measured. Impaza but not sildenafil increased penis length at mount after 14 and 28 days of treatment. The compounds failed to modify sexual incentive motivation or copulatory behavior. It is suggested that Impaza enhanced intracavernous pressure, as such a pressure increase is the most likely explanation for enhanced penis length at mount. This effect, together with an absence of motivational actions, suggests that Impaza may be the most valuable treatment for erectile dysfunction.

  7. Serum high-density lipoprotein cholesterol levels, their relationship with baseline functional and cognitive status, and their utility in predicting mortality in nonagenarians.

    Science.gov (United States)

    Formiga, Francesc; Ferrer, Assumpta; Chivite, David; Pinto, Xavier; Cuerpo, Sandra; Pujol, Ramón

    2011-07-01

    Little is known about the role of high-density lipoprotein cholesterol (HDL-C) in oldest-old subjects. The aim of this study is to evaluate the association between HDL-C levels and physical and cognitive performance indicators in nonagenarians, and also to determine the influence of HDL-C levels on the 3-year mortality risk. The data analyzed were taken from the NonaSantfeliu Study. Functional status was determined by the Lawton-Brody Index (LI) for instrumental activities of daily living (IADL) and the Barthel Index (BI) for basic activities (BADL). Cognition was assessed using the Spanish version of the Mini-Mental State Examination (MEC). The sample consisted of 49 women (79%) and 13 men, aged 94.3 ± 2.6 years. Mean HDL-C levels were 60 ± 16 mg/dL, and 16 subjects (25.8%) had low HDL-C values. HDL-C levels did correlate with BI (r = 0.28, P = 0.02) and LI (r = 0.32, P = 0.01), but not with MEC (r = 0.18, P = 0.15). Normal HDL-C levels at baseline were significantly associated with higher BI scores (P < 0.006, odds ratio [OR] = 1.03, 95% confidence interval [CI] = 1.01-1.05) and a lower number of prescription drugs used (P < 0.04, OR = 0.71, 95% CI = 0.49-0.99). Baseline HDL-C levels were significantly lower among the group of nonagenarians who died within the 3 years of follow up (P = 0.02). However, after adjusting for potential confounders, the association between HDL-C and mortality lost significance. Higher levels of HDL-C correlate with better functional status and less use of prescribed drugs in nonagenarians. However, the relationship between low HDL-C levels and long-term mortality in this population remains unclear. © 2011 Japan Geriatrics Society.

  8. Impactful study of dual work function, underlap and hetero gate dielectric on TFET with different drain doping profile for high frequency performance estimation and optimization

    Science.gov (United States)

    Yadav, Dharmendra Singh; Sharma, Dheeraj; Raad, Bhagwan Ram; Bajaj, Varun

    2016-08-01

    This manuscript presents a comparative study of different combination for the dual workfunction gate material, underlap and hetero gate dielectric tunnel field-effect transistors (TFET's). Their performances have been analyzed in terms of ON-state current, ambipolar behaviour and RF response along with different drain doping profile. For this, the Dual work function of gate provides enhancement in ON-state current by reducing the tunnel barrier width at source/channel interface. Whereas, the underlap of gate is done near to the drain region, helps in reduction of ambipolar conduction by creating deficiency of hole for the conduction, which is major hurdle for TFET. Further, the combinations of the dual workfunction and underlap give combine advantages of both such as improve ON-state current and suppressed ambipolar current. Apart from this, the combination of hetero gate dielectric dual workfunction under lapping leads to superior device performance in terms of ON-state current and ambipolar behaviour. The use of hetero gate dielectric and Gaussian doping profile with gate underlap reduces the gate to drain capacitance that also improves the RF parameters of the device.

  9. Baseline characteristics in the Avoiding Cardiovascular events through Combination therapy in Patients Living with Systolic Hypertension (ACCOMPLISH) trial: a hypertensive population at high cardiovascular risk.

    Science.gov (United States)

    Weber, Michael A; Bakris, George L; Dahlöf, Björn; Pitt, Bertram; Velazquez, Eric; Gupte, Jitendra; Lefkowitz, Martin; Hester, Allen; Shi, Victor; Weir, Matthew; Kjeldsen, Sverre; Massie, Barry; Nesbitt, Shawna; Ofili, Elizabeth; Jamerson, Kenneth

    2007-01-01

    ACCOMPLISH is the first trial designed to compare the effects on major fatal and non-fatal cardiovascular endpoints of two forms of antihypertensive combination therapy: benazepril plus hydrochlorothiazide and amlodipine plus benazepril in hypertensive patients at high cardiovascular risk. Enrollment for this trial is now complete and this report describes the clinical characteristics of the study cohort. Patients with hypertension and a previous history of cardiovascular events, strokes or diabetes mellitus were randomized to double-blind treatment with either of the two combination regimens. The data in this report detail the clinical history and demographic characteristics in patients immediately prior to randomization to study drugs. A total of 11,454 patients were randomized. Mean age (+/-SD) was 68.4+/-6.9 years, 60% were men, and 1360 (12%) were African American. Mean body mass index (BMI) was 31.0+/-6.3 kg/m(2). At study entry, 46% of patients had a history of acute coronary syndromes, coronary artery bypass grafts or percutaneous coronary interventions; 13% had a history of stroke. A history of diabetes mellitus was reported in 6928 (60%) of patients. Mean blood pressure at baseline (on prior hypertension therapy) was 145.4/80.0 mmHg; only 38% of patients had a BP less than 140/90 mmHg. Overall, 97% of patients had received previous antihypertensive treatment (74% on at least two drugs); 53% were on oral diabetes therapy or insulin, 68% on anti-lipid therapy and 63% on anti-platelet agents. In summary, the ACCOMPLISH trial has recruited hypertensive patients at high risk of cardiovascular morbidity and mortality. It is noteworthy that the mean BMI of 31 in this cohort is clearly above the accepted diagnostic criterion of obesity and that 60% of patients are diabetic, possibly reflecting secular trends in clinical disease.

  10. Time-gated optical projection tomography.

    Science.gov (United States)

    Bassi, Andrea; Brida, Daniele; D'Andrea, Cosimo; Valentini, Gianluca; Cubeddu, Rinaldo; De Silvestri, Sandro; Cerullo, Giulio

    2010-08-15

    We present an imaging technique that combines optical projection tomography with ballistic imaging using ultrafast time gating. The method provides high-resolution reconstruction of scattering samples and is suitable for three-dimensional (3D) imaging of biological models.

  11. Smart gating membranes with in situ self-assembled responsive nanogels as functional gates

    Science.gov (United States)

    Luo, Feng; Xie, Rui; Liu, Zhuang; Ju, Xiao-Jie; Wang, Wei; Lin, Shuo; Chu, Liang-Yin

    2015-10-01

    Smart gating membranes, inspired by the gating function of ion channels across cell membranes, are artificial membranes composed of non-responsive porous membrane substrates and responsive gates in the membrane pores that are able to dramatically regulate the trans-membrane transport of substances in response to environmental stimuli. Easy fabrication, high flux, significant response and strong mechanical strength are critical for the versatility of such smart gating membranes. Here we show a novel and simple strategy for one-step fabrication of smart gating membranes with three-dimensionally interconnected networks of functional gates, by self-assembling responsive nanogels on membrane pore surfaces in situ during a vapor-induced phase separation process for membrane formation. The smart gating membranes with in situ self-assembled responsive nanogels as functional gates show large flux, significant response and excellent mechanical property simultaneously. Because of the easy fabrication method as well as the concurrent enhancement of flux, response and mechanical property, the proposed smart gating membranes will expand the scope of membrane applications, and provide ever better performances in their applications.

  12. Rapidly Reconfigurable All-Optical Universal Logic Gates

    Energy Technology Data Exchange (ETDEWEB)

    Goddard, L L; Kallman, J S; Bond, T C

    2006-06-21

    We present designs and simulations for a highly cascadable, rapidly reconfigurable, all-optical, universal logic gate. We will discuss the gate's expected performance, e.g. speed, fanout, and contrast ratio, as a function of the device layout and biasing conditions. The gate is a three terminal on-chip device that consists of: (1) the input optical port, (2) the gate selection port, and (3) the output optical port. The device can be built monolithically using a standard multiple quantum well graded index separate confinement heterostructure laser configuration. The gate can be rapidly and repeatedly reprogrammed to perform any of the basic digital logic operations by using an appropriate analog electrical or optical signal at the gate selection port. Specifically, the same gate can be selected to execute one of the 2 basic unary operations (NOT or COPY), or one of the 6 binary operations (OR, XOR, AND, NOR, XNOR, or NAND), or one of the many logic operations involving more than two inputs. The speed of the gate for logic operations as well as for reprogramming the function of the gate is primarily limited to the small signal modulation speed of a laser, which can be on the order of tens of GHz. The reprogrammable nature of the universal gate offers maximum flexibility and interchangeability for the end user since the entire application of a photonic integrated circuit built from cascaded universal logic gates can be changed simply by adjusting the gate selection port signals.

  13. Magic Baseline Beta Beam

    CERN Document Server

    Agarwalla, Sanjib Kumar; Raychaudhuri, Amitava

    2007-01-01

    We study the physics reach of an experiment where neutrinos produced in a beta-beam facility at CERN are observed in a large magnetized iron calorimeter (ICAL) at the India-based Neutrino Observatory (INO). The CERN-INO distance is close to the so-called "magic" baseline which helps evade some of the parameter degeneracies and allows for a better measurement of the neutrino mass hierarchy and $\\theta_{13}$.

  14. Rationing with baselines

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Moreno-Ternero, Juan D.; Østerdal, Lars Peter Raahave

    2013-01-01

    We introduce a new operator for general rationing problems in which, besides conflicting claims, individual baselines play an important role in the rationing process. The operator builds onto ideas of composition, which are not only frequent in rationing, but also in related problems...... such as bargaining, choice, and queuing. We characterize the operator and show how it preserves some standard axioms in the literature on rationing. We also relate it to recent contributions in such literature....

  15. The TDAQ Baseline Architecture

    CERN Multimedia

    Wickens, F J

    The Trigger-DAQ community is currently busy preparing material for the DAQ, HLT and DCS TDR. Over the last few weeks a very important step has been a series of meetings to complete agreement on the baseline architecture. An overview of the architecture indicating some of the main parameters is shown in figure 1. As reported at the ATLAS Plenary during the February ATLAS week, the main area where the baseline had not yet been agreed was around the Read-Out System (ROS) and details in the DataFlow. The agreed architecture has: Read-Out Links (ROLs) from the RODs using S-Link; Read-Out Buffers (ROB) sited near the RODs, mounted in a chassis - today assumed to be a PC, using PCI bus at least for configuration, control and monitoring. The baseline assumes data aggregation, in the ROB and/or at the output (which could either be over a bus or in the network). Optimization of the data aggregation will be made in the coming months, but the current model has each ROB card receiving input from 4 ROLs, and 3 such c...

  16. Getting started with FortiGate

    CERN Document Server

    Fabbri, Rosato

    2013-01-01

    This book is a step-by-step tutorial that will teach you everything you need to know about the deployment and management of FortiGate, including high availability, complex routing, various kinds of VPN working, user authentication, security rules and controls on applications, and mail and Internet access.This book is intended for network administrators, security managers, and IT pros. It is a great starting point if you have to administer or configure a FortiGate unit, especially if you have no previous experience. For people that have never managed a FortiGate unit, the book helpfully walks t

  17. Calibration of submerged multi-sluice gates

    Directory of Open Access Journals (Sweden)

    Mohamed F. Sauida

    2014-09-01

    The main objective of this work is to study experimentally and verify empirically the different parameters affecting the discharge through submerged multiple sluice gates (i.e., the expansion ratios, gates operational management, etc.. Using multiple regression analysis of the experimental results, a general equation for discharge coefficient is developed. The results show, that the increase in the expansion ratio and the asymmetric operation of gates, give higher values for the discharge coefficient. The obtained predictions of the discharge coefficient using the developed equations are compared to the experimental data. The present developed equations showed good consistency and high accuracy.

  18. Evolution of interfacial Fermi level in In{sub 0.53}Ga{sub 0.47}As/high-κ/TiN gate stacks

    Energy Technology Data Exchange (ETDEWEB)

    Carr, Adra; Rozen, John; Frank, Martin M.; Ando, Takashi; Cartier, Eduard A.; Kerber, Pranita; Narayanan, Vijay; Haight, Richard [IBM T. J. Watson Research Center, P.O. Box 218, Yorktown Heights, New York 10598 (United States)

    2015-07-06

    The net charge state was probed of metal-oxide-semiconductor gate stacks consisting of In{sub 0.53}Ga{sub 0.47}As /high-κ dielectric/5 nm TiN, for both Al{sub 2}O{sub 3} and HfO{sub 2} dielectrics, via investigation of band bending at the InGaAs/high-κ interface. Using pump-probe photoelectron spectroscopy, changes to band bending were studied for each sequential layer deposited onto the InGaAs substrate and subsequent annealing up to 600 °C. Two behavioral regions were observed in annealing studies: (1) a lower temperature (<350 °C) region, attributed to changes at the high-κ/TiN interface, and (2) a higher temperature region (> 350 °C), associated with a net positive charge increase within the oxide. These band bending measurements delineate the impact of processing steps inherently inaccessible via capacitance-voltage electrical characterization.

  19. High-permitivity cerium oxide prepared by molecular beam deposition as gate dielectric and passivation layer and applied to AlGaN/GaN power high electron mobility transistor devices

    Science.gov (United States)

    Chiu, Yu Sheng; Liao, Jen Ting; Lin, Yueh Chin; Chien Liu, Shin; Lin, Tai Ming; Iwai, Hiroshi; Kakushima, Kuniyuki; Chang, Edward Yi

    2016-05-01

    High-κ cerium oxide (CeO2) was applied to AlGaN/GaN high-electron-mobility transistors (HEMTs) as a gate insulator and a passivation layer by molecular beam deposition (MBD) for high-power applications. From capacitance-voltage (C-V) measurement results, the dielectric constant of the CeO2 film was 25.2. The C-V curves showed clear accumulation and depletion behaviors with a small hysteresis (20 mV). Moreover, the interface trap density (D it) was calculated to be 5.5 × 1011 eV-1 cm-2 at 150 °C. A CeO2 MOS-HEMT was fabricated and demonstrated a low subthreshold swing (SS) of 87 mV/decade, a high ON/OFF drain current ratio (I ON/I OFF) of 1.14 × 109, and a low gate leakage current density (J leakage) of 2.85 × 10-9 A cm-2 with an improved dynamic ON-resistance (R ON), which is about one order of magnitude lower than that of a conventional HEMT.

  20. Sodium beta-alumina thin films as gate dielectrics for AlGaN/GaN metal-insulator-semiconductor high-electron-mobility transistors

    Institute of Scientific and Technical Information of China (English)

    Tian Ben-Lang; Chen Chao; Li Yan-Rong; Zhang Wan-Li; Liu Xing-Zhao

    2012-01-01

    Sodium beta-alumina (SBA) is deposited on AlGaN/GaN by using a co-deposition process with sodium and Al2O3 as the precursors.The X-ray diffraction (XRD) spectrum reveals that the deposited thin film is amorphous.The binding energy and composition of the deposited thin film,obtained from the X-ray photoelectron spectroscopy (XPS)measurement,are consistent with those of SBA.The dielectric constant of the SBA thin film is about 50.Each of the capacitance-voltage characteristics obtained at five different frequencies shows a high-quality interface between SBA and A1GaN.The interface trap density of metal-insulator-semiconductor high-electron-mobility transistor (MISHEMT)is measured to be (3.5~9.5)× 1010 cm-2.eV-1 by the conductance method.The fixed charge density of SBA dielectric is on the order of 2.7x1012 cm-2.Compared with the AlGaN/GaN metal semiconductor hetcrostructure high-electron-mobility transistor (MESHEMT),the AlGaN/GaN MISHEMT usually has a threshold voltage that shifts negatively.However,the threshold voltage of the AlGaN/GaN MISHEMT using SBA as the gate dielectric shifts positively from -5.5 V to-3.5 V.From XPS results,the surface valence-band maximum (VBM-EF) of AlGaN is found to decrease from 2.56 eV to 2.25 eV after the SBA thin film deposition.The possible reasons why the threshold voltage of AlGaN/GaN MISHEMT with the SBA gate dielectric shifts positively are the influence of SBA on surface valence-band maximum (VBM-EF),the reduction of interface traps and the effects of sodium ions,and/or the fixed charges in SBA on the two-dimensional electron gas (2DEG).

  1. Step buffer layer of Al0.25Ga0.75N/Al0.08Ga0.92N on P-InAlN gate normally-off high electron mobility transistors

    Science.gov (United States)

    Shrestha, Niraj M.; Li, Yiming; Chang, E. Y.

    2016-07-01

    Normally-off AlGaN/GaN high electron mobility transistors (HEMTs) are indispensable devices for power electronics as they can greatly simplify circuit designs in a cost-effective way. In this work, the electrical characteristics of p-type InAlN gate normally-off AlGaN/GaN HEMTs with a step buffer layer of Al0.25Ga0.75N/Al0.1Ga0.9N is studied numerically. Our device simulation shows that a p-InAlN gate with a step buffer layer allows the transistor to possess normally-off behavior with high drain current and high breakdown voltage simultaneously. The gate modulation by the p-InAlN gate and the induced holes appearing beneath the gate at the GaN/Al0.25Ga0.75N interface is because a hole appearing in the p-InAlN layer can effectively vary the threshold voltage positively. The estimated threshold voltage of the normally-off HEMTs explored is 2.5 V at a drain bias of 25 V, which is 220% higher than the conventional p-AlGaN normally-off AlGaN/GaN gate injection transistor (GIT). Concurrently, the maximum current density of the explored HEMT at a drain bias of 10 V slightly decreases by about 7% (from 240 to 223 mA mm-1). At a drain bias of 15 V, the current density reached 263 mA mm-1. The explored structure is promising owing to tunable positive threshold voltage and the maintenance of similar current density; notably, its breakdown voltage significantly increases by 36% (from 800 V, GIT, to 1086 V). The engineering findings of this study indicate that novel p-InAlN for both the gate and the step buffer layer can feature a high threshold voltage, large current density and high operating voltage for advanced AlGaN/GaN HEMT devices.

  2. 基于高速肖特基二极管的100 ps瞬态取样门设计与仿真%Design and simulation of 100 ps transient sampling gate based on high speed Schottky diode

    Institute of Scientific and Technical Information of China (English)

    陈宇晓; 尹显东; 唐丹; 杨谟华

    2006-01-01

    The picosecond transient sampling gate is mainly applied in laser fusion and high energy physics experiments for single high-speed pulse real-time sampling. A new balanced sampling gate based on monolithic Schottky bridge quad diodes is put forward in this paper as well as its model and circuit design. The circuit simulation shows that the symmetric strobe design ensures that the sampling interval is 100 ps and the sampling gate bandwidth is 4.4 GHz when the strobe pulse width is 100 ps. The gate can be used in multi-beam ultrashort laser pulses sampling.%皮秒级瞬态取样门主要应用于激光聚变实验和高能物理实验中,对单次高速脉冲进行实时取样.提出了一种新颖的基于肖特基二极管桥的平衡取样门,给出其模型和具体电路设计.电路仿真结果表明,对称的选通设计保证了选通脉宽为100 ps时,取样间隔也为100 ps,取样门带宽为4.4 GHz,可应用于多路超短激光脉冲取样.

  3. High-performance sidewall damascened tri-gate poly-si TFTs with the strain proximity free technique and stress memorization technique

    Science.gov (United States)

    Hsieh, Dong-Ru; Kuo, Po-Yi; Lin, Jer-Yi; Chen, Yi-Hsuan; Chang, Tien-Shun; Chao, Tien-Sheng

    2017-02-01

    In this paper, strained channel-sidewall damascened tri-gate polycrystalline silicon thin-film transistors (SC-SWDTG TFTs) have been successfully fabricated and then demonstrated by an innovative process flow. This process flow without the use of advanced lithography processes combines the sidewall damascened technique (SWDT) and two strain techniques, namely, the strain proximity free technique (SPFT), and the stress memorization technique (SMT), in the poly-Si channels. It has some advantages: (1) the channel shapes and dimensions can be effectively controlled by the wet etching processes and the deposition thickness of the tetraethoxysilane (TEOS) oxide; (2) the source/drain (S/D) resistance can be significantly decreased by the formation of the raised S/D structures; (3) the SPFT, SMT, and the rapid thermal annealing (RTA) treatment can enhance the performance of the SC-SWDTG TFTs without the limitation of the highly scaling stress liner thickness in deep-submicron TFTs. Thus, the SC-SWDTG TFTs exhibit a steep subthreshold swing (S.S.) ˜ 110 mV/dec., an extremely small drain induced barrier lowing (DIBL) ˜12.2 mV V-1, and a high on/off ratio ˜107 (V D = 1 V) without plasma treatments for future three-dimensional integrated circuits (3D ICs) applications.

  4. Effect of reverse body bias on hot-electron-induced punchthrough reliability of pMOSFETs with thin gate dielectric at high temperatures

    Science.gov (United States)

    Kang, YongHa; Kim, JongKyun; Lee, NamHyun; Oh, MinGeon; Hwang, YuChul; Moon, ByungMoo

    2016-06-01

    The effect of the reverse body bias V SB on the hot-electron-induced punch-through (HEIP) reliability of pMOSFETs with a thin gate dielectric at high temperatures was investigated for the first time. Experimental results indicate that the reverse V SB increased the HEIP degradation for a thin pMOSFET because of the increase in the maximum electric field E m due to the increase in the threshold voltage V th. The sensitivity of HEIP degradation to V SB increased with increasing body effect coefficient γ at a given oxide thickness T ox. However, a thin device (22 Å) showed a much stronger dependence of HEIP degradation on V SB due to the decrease in the velocity saturation length l, although it had a smaller γ than a thick device (60 Å). These new observations suggest that the body bias technique for improving circuit performance can cause a reliability problem of nanoscale pMOSFETs at high temperatures and impose a significant limitation on CMOS device scaling.

  5. Monte Carlo Simulations of High-speed, Time-gated MCP-based X-ray Detectors: Saturation Effects in DC and Pulsed Modes and Detector Dynamic Range

    Energy Technology Data Exchange (ETDEWEB)

    Craig Kruschwitz, Ming Wu, Ken Moy, Greg Rochau

    2008-10-31

    We present here results of continued efforts to understand the performance of microchannel plate (MCP)–based, high-speed, gated, x-ray detectors. This work involves the continued improvement of a Monte Carlo simulation code to describe MCP performance coupled with experimental efforts to better characterize such detectors. Our goal is a quantitative description of MCP saturation behavior in both static and pulsed modes. We have developed a new model of charge buildup on the walls of the MCP channels and measured its effect on MCP gain. The results are compared to experimental data obtained with a short-pulse, high-intensity ultraviolet laser; these results clearly demonstrate MCP saturation behavior in both DC and pulsed modes. The simulations compare favorably to the experimental results. The dynamic range of the detectors in pulsed operation is of particular interest when fielding an MCP–based camera. By adjusting the laser flux we study the linear range of the camera. These results, too, are compared to our simulations.

  6. Allowable Generalized Quantum Gates

    Institute of Scientific and Technical Information of China (English)

    LONG Gui-Lu; LIU Yang; WANG Chuan

    2009-01-01

    In this paper, we give the most general duality gates, or generalized quantum gates in duality quantum computers. Here we show by explicit construction that a n-bit duality quantum computer with d slits can be simulated perfectly with an ordinary quantum computer with n qubits and one auxiliary qudit. Using this model, we give the most general form of duality gates which is of the form Σ(d-1)(i=0)piUi, and the Pi's are complex numbers with module less or equal to I and constrained by |Σipi|≤1.

  7. CDP-choline: effects of the procholine supplement on sensory gating and executive function in healthy volunteers stratified for low, medium and high P50 suppression.

    Science.gov (United States)

    Knott, Verner; Smith, Dylan; de la Salle, Sara; Impey, Danielle; Choueiry, Joelle; Beaudry, Elise; Smith, Meaghan; Saghir, Salman; Ilivitsky, Vadim; Labelle, Alain

    2014-12-01

    Diminished auditory sensory gating and associated neurocognitive deficits in schizophrenia have been linked to altered expression and function of the alpha-7 nicotinic acetycholinergic receptor (α7 nAChR), the targeting of which may have treatment potential. Choline is a selective α7 nAChR agonist and the aim of this study was to determine whether cytidine 5'-diphosphocholine (CDP-choline), or citicoline, a dietary source of choline, increases sensory gating and cognition in healthy volunteers stratified for gating level. In a randomized, placebo-controlled, double-blind design involving acute administration of low, moderate doses (500 mg, 1000 mg) of CDP-choline, 24 healthy volunteers were assessed for auditory gating as indexed by suppression of the P50 event-related potential (ERP) in a paired-stimulus (S1, S2) paradigm, and for executive function as measured by the Groton Maze Learning Task (GMLT) of the CogState Schizophrenia Battery. CDP-choline improved gating (1000 mg) and suppression of the S2 P50 response (500 mg, 1000 mg), with the effects being selective for individuals with low gating (suppression) levels. Tentative support was also shown for increased GMLT performance (500 mg) in low suppressors. These preliminary findings with CDP-choline in a healthy, schizophrenia-like surrogate sample are consistent with a α7 nAChR mechanism and support further trials with choline as a pro-cognitive strategy.

  8. Specific expression of the human voltage-gated proton channel Hv1 in highly metastatic breast cancer cells, promotes tumor progression and metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yifan [The Key Laboratory of Bioactive Materials, Ministry of Education, School of Physics Science, Nankai University, Tianjin 300071 (China); Li, Shu Jie, E-mail: shujieli@nankai.edu.cn [The Key Laboratory of Bioactive Materials, Ministry of Education, School of Physics Science, Nankai University, Tianjin 300071 (China); Pan, Juncheng [The Key Laboratory of Bioactive Materials, Ministry of Education, School of Physics Science, Nankai University, Tianjin 300071 (China); Che, Yongzhe, E-mail: cheli@nankai.edu.cn [The Key Laboratory of Bioactive Materials, Ministry of Education, School of Medicine, Nankai University, Tianjin 300071 (China); Yin, Jian [Cancer Institute and Hospital, Tianjin Medical University, Tianjin 300060 (China); Zhao, Qing [The Key Laboratory of Bioactive Materials, Ministry of Education, School of Physics Science, Nankai University, Tianjin 300071 (China)

    2011-08-26

    Highlights: {yields} Hv1 is specifically expressed in highly metastatic human breast tumor tissues. {yields} Hv1 regulates breast cancer cytosolic pH. {yields} Hv1 acidifies extracellular milieu. {yields} Hv1 exacerbates the migratory ability of metastatic cells. -- Abstract: The newly discovered human voltage-gated proton channel Hv1 is essential for proton transfer, which contains a voltage sensor domain (VSD) without a pore domain. We report here for the first time that Hv1 is specifically expressed in the highly metastatic human breast tumor tissues, but not in poorly metastatic breast cancer tissues, detected by immunohistochemistry. Meanwhile, real-time RT-PCR and immunocytochemistry showed that the expression levels of Hv1 have significant differences among breast cancer cell lines, MCF-7, MDA-MB-231, MDA-MB-468, MDA-MB-453, T-47D and SK-BR-3, in which Hv1 is expressed at a high level in highly metastatic human breast cancer cell line MDA-MB-231, but at a very low level in poorly metastatic human breast cancer cell line MCF-7. Inhibition of Hv1 expression in the highly metastatic MDA-MB-231 cells by small interfering RNA (siRNA) significantly decreases the invasion and migration of the cells. The intracellular pH of MDA-MB-231 cells down-regulated Hv1 expression by siRNA is obviously decreased compared with MDA-MB-231 with the scrambled siRNA. The expression of matrix metalloproteinase-2 and gelatinase activity in MDA-MB-231 cells suppressed Hv1 by siRNA were reduced. Our results strongly suggest that Hv1 regulates breast cancer intracellular pH and exacerbates the migratory ability of metastatic cells.

  9. ECG-based gating in ultra high field cardiovascular magnetic resonance using an independent component analysis approach

    OpenAIRE

    Krug, Johannes W; Rose, Georg; Clifford, Gari D.; Oster, Julien

    2013-01-01

    Background In Cardiovascular Magnetic Resonance (CMR), the synchronization of image acquisition with heart motion is performed in clinical practice by processing the electrocardiogram (ECG). The ECG-based synchronization is well established for MR scanners with magnetic fields up to 3 T. However, this technique is prone to errors in ultra high field environments, e.g. in 7 T MR scanners as used in research applications. The high magnetic fields cause severe magnetohydrodynamic (MHD) effects w...

  10. In situ atomic layer nitridation on the top and down regions of the amorphous and crystalline high-K gate dielectrics

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Meng-Chen [Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Lee, Min-Hung [Institute of Electro-Optical Science and Technology, National Taiwan Normal University, Taipei 11677, Taiwan (China); Kuo, Chin-Lung; Lin, Hsin-Chih [Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Chen, Miin-Jang, E-mail: mjchen@ntu.edu.tw [Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China)

    2016-11-30

    Highlights: • The structural and electrical characteristics of the ZrO{sub 2} high-K dielectrics, treated with the in situ atomic layer doping of nitrogen into the top and down regions (top and down nitridation, TN and DN, respectively), were investigated. • The amorphous DN sample has a lower leakage current density (J{sub g}) than the amorphous TN sample, attributed to the formation of SiO{sub x}N{sub y} in the interfacial layer (IL). • The crystalline TN sample exhibited a lower CET and a similar J{sub g} as compared with the crystalline DN sample, which can be ascribed to the suppression of IL regrowth. • The crystalline ZrO{sub 2} with in situ atomic layer doping of nitrogen into the top region exhibited superior scaling limit, electrical characteristics, and reliability. - Abstract: Amorphous and crystalline ZrO{sub 2} gate dielectrics treated with in situ atomic layer nitridation on the top and down regions (top and down nitridation, abbreviated as TN and DN) were investigated. In a comparison between the as-deposited amorphous DN and TN samples, the DN sample has a lower leakage current density (J{sub g}) of ∼7 × 10{sup −4} A/cm{sup 2} with a similar capacitance equivalent thickness (CET) of ∼1.53 nm, attributed to the formation of SiO{sub x}N{sub y} in the interfacial layer (IL). The post-metallization annealing (PMA) leads to the transformation of ZrO{sub 2} from the amorphous to the crystalline tetragonal/cubic phase, resulting in an increment of the dielectric constant. The PMA-treated TN sample exhibits a lower CET of 1.22 nm along with a similar J{sub g} of ∼1.4 × 10{sup −5} A/cm{sup 2} as compared with the PMA-treated DN sample, which can be ascribed to the suppression of IL regrowth. The result reveals that the nitrogen engineering in the top and down regions has a significant impact on the electrical characteristics of amorphous and crystalline ZrO{sub 2} gate dielectrics, and the nitrogen incorporation at the top of crystalline

  11. Slide Gate Bricks

    Institute of Scientific and Technical Information of China (English)

    Wang Jing; Peng Xigao

    2010-01-01

    @@ 1 Scope This standard specifies the classification,shape,dimension,technical requirements,test methods,quality appraisal procedures,packing,marking,transportation,storage,and quality certificate of slide gate bricks.

  12. Transfer-less flexible and transparent high-κ/metal gate germanium devices on bulk silicon (100)

    KAUST Repository

    Nassar, Joanna M.

    2014-08-01

    Flexible wearable electronics have been of great interest lately for the development of innovative future technology for various interactive applications in the field of consumer electronics and advanced healthcare, offering the promise of low-cost, lightweight, and multifunctionality. In the pursuit of this trend, high mobility channel materials need to be investigated on a flexible platform, for the development of flexible high performance devices. Germanium (Ge) is one of the most attractive alternatives for silicon (Si) for high-speed computational applications, due its higher hole and electron mobility. Thus, in this work we show a cost effective CMOS compatible process for transforming conventional rigid Ge metal oxide semiconductor capacitors (MOSCAPS) into a mechanically flexible and semi-transparent platform. Devices exhibit outstanding bendability with a bending radius of 0.24 cm, and semi-transparency up to 30 %, varying with respect to the diameter size of the release holes array.

  13. Cradle-to-Gate Impact Assessment of a High-Pressure Die-Casting Safety-Relevant Automotive Component

    Science.gov (United States)

    Cecchel, Silvia; Cornacchia, Giovanna; Panvini, Andrea

    2016-09-01

    The mass of automotive components has a direct influence on several aspects of vehicle performance, including both fuel consumption and tailpipe emissions, but the real environmental benefit has to be evaluated considering the entire life of the products with a proper life cycle assessment. In this context, the present paper analyzes the environmental burden connected to the production of a safety-relevant aluminum high-pressure die-casting component for commercial vehicles (a suspension cross-beam) considering all the phases connected to its manufacture. The focus on aluminum high-pressure die casting reflects the current trend of the industry and its high energy consumption. This work shows a new method that deeply analyzes every single step of the component's production through the implementation of a wide database of primary data collected thanks to collaborations of some automotive supplier companies. This energy analysis shows significant environmental benefits of aluminum recycling.

  14. An anti-ferroelectric gated Landau transistor to achieve sub-60 mV/dec switching at low voltage and high speed

    Science.gov (United States)

    Karda, Kamal; Jain, Ankit; Mouli, Chandra; Alam, Muhammad Ashraful

    2015-04-01

    Landau field effect transistors promise to lower the power-dissipation of integrated circuits (ICs) by reducing the subthreshold swing (S) below the Boltzmann limit of 60 mV/dec. The key idea is to replace the classical gate insulator with dielectrics that exhibit negative capacitance (NC) associated with double-well energy landscape, for example, ferroelectrics (FE), air-gap capacitors, or a combination thereof. Indeed, S is dramatically reduced, constrained only by the limits of hysteresis-free operation. Unfortunately, the following limitations apply (i) the need for capacitance matching constrains steep S only to the small subthreshold region for FE based negative capacitance field effect transistor (NCFET) and requires an insulator too thick for sub-20 nm scaling; (ii) the kinetics of mechanical switching for airgap based NCFET obviate high-speed operation; and (iii) the lattice mismatch between the substrate and the dielectric makes defect-free integration difficult. In this article, we demonstrate that a FET integrated with 10 nm HfO2-based anti-ferroelectric and FE hetero stack would achieve ultralow S with ON-current ( Io n) at par with classical transistors at significantly lower voltage and would simplify integration. Our results address the well-known challenges/criticisms of classical Landau transistors, thereby, making them technology relevant for modern ICs.

  15. Preliminary results on low power sigmoid neuron transistor response in 28 nm high-k metal gate Fully Depleted SOI technology

    Science.gov (United States)

    Galy, Ph.; Dehan, P.; Jimenez, J.; Heitz, B.

    2013-11-01

    The purpose of this paper is to describe a preliminary approach to achieve a sigmoid neuron transistor response using the 28 nm high-k metal gate Fully Depleted SOI (FDSOI) technology. It is well known that a neural network is an ambitious way to handle signal and/or data flow. Of interest also is the 'learning phase' of the proposed structure. However, the major difficulty of such structures, where the elementary device is a "Neuron Design (ND)" is in their integration. The elementary ND is based upon a circuit with at least ten interconnected CMOS transistors in order to obtain a sigmoid response activation function (in this example) with multiple inputs typically as per the McCulloch and Pitts model. Given that a large number of NDs are required to build an Artificial Neural Network (ANN), the power consumption of such a structure is a key topic that is also addressed. Another open question concerns the dispersion response due to process variability. This study reports on a new single undoped Formal Neuron Transistor (NT) solution.

  16. Functional proteins involved in regulation of intracellular Ca(2+) for drug development: chronic nicotine treatment upregulates L-type high voltage-gated calcium channels.

    Science.gov (United States)

    Katsura, Masashi; Ohkuma, Seitaro

    2005-03-01

    Neurochemical mechanisms underlying drug dependence and withdrawal syndrome remain unclear. In this review, we discuss how chronic nicotine exposure to neurons affects expression of diazepam binding inhibitor (DBI), an endogenous anxiogenic neuropeptide supposed to be a common substance participating drug dependence, and function of L-type high voltage-gated Ca(2+) channels (HVCCs). We also discuss the functional interaction between DBI and L-type HVCCs in nicotine dependence. Both DBI levels and [(45)Ca(2+)] influx significantly increased in the brain from mice treated with nicotine for long term, which was further enhanced after abrupt cessation of nicotine and was abolished by nicotinic acetylcholine receptor (nAChR) antagonists. Similar responses of DBI expression and L-type HVCC function were observed in cerebral cortical neurons after sustained exposure to nicotine. In addition, increased DBI expression was inhibited by antagonists of nAChR and L-type HVCCs. Sustained exposure of neurons to nicotine significantly enhanced expression of alpha(1) and alpha(2)/delta(1) subunits for L-type HVCCs and caused an increase in the B(max) value of [(3)H]verapamil binding to the particulate fractions. Therefore, it is concluded that the alterations in DBI expression is mediated via increased influx of Ca(2+) through upregulated L-type HVCCs and these neurochemical changes have a close relationship with development of nicotine dependence and/or its withdrawal syndrome.

  17. Synthesizing biomolecule-based Boolean logic gates.

    Science.gov (United States)

    Miyamoto, Takafumi; Razavi, Shiva; DeRose, Robert; Inoue, Takanari

    2013-02-15

    One fascinating recent avenue of study in the field of synthetic biology is the creation of biomolecule-based computers. The main components of a computing device consist of an arithmetic logic unit, the control unit, memory, and the input and output devices. Boolean logic gates are at the core of the operational machinery of these parts, and hence to make biocomputers a reality, biomolecular logic gates become a necessity. Indeed, with the advent of more sophisticated biological tools, both nucleic acid- and protein-based logic systems have been generated. These devices function in the context of either test tubes or living cells and yield highly specific outputs given a set of inputs. In this review, we discuss various types of biomolecular logic gates that have been synthesized, with particular emphasis on recent developments that promise increased complexity of logic gate circuitry, improved computational speed, and potential clinical applications.

  18. 25 GHz embedded-gate graphene transistors with high-k dielectrics on extremely flexible plastic sheets.

    Science.gov (United States)

    Lee, Jongho; Ha, Tae-Jun; Li, Huifeng; Parrish, Kristen N; Holt, Milo; Dodabalapur, Ananth; Ruoff, Rodney S; Akinwande, Deji

    2013-09-24

    Despite the widespread interest in graphene electronics over the past decade, high-performance graphene field-effect transistors (GFETs) on flexible substrates have been rarely achieved, even though this atomic sheet is widely understood to have greater prospects for flexible electronic systems. In this article, we report detailed studies on the electrical and mechanical properties of vapor synthesized high-quality monolayer graphene integrated onto flexible polyimide substrates. Flexible graphene transistors with high-k dielectric afforded intrinsic gain, maximum carrier mobilities of 3900 cm(2)/V·s, and importantly, 25 GHz cutoff frequency, which is more than a factor of 2.5 times higher than prior results. Mechanical studies reveal robust transistor performance under repeated bending, down to 0.7 mm bending radius, whose tensile strain is a factor of 2-5 times higher than in prior studies. In addition, integration of functional coatings such as highly hydrophobic fluoropolymers combined with the self-passivation properties of the polyimide substrate provides water-resistant protection without compromising flexibility, which is an important advancement for the realization of future robust flexible systems based on graphene.

  19. Low-dose adaptive sequential scan for dual-source CT coronary angiography in patients with high heart rate: Comparison with retrospective ECG gating

    Energy Technology Data Exchange (ETDEWEB)

    Xu Lei, E-mail: leixu2001@hotmail.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Yang Lin, E-mail: anna7949@163.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Zhang Zhaoqi, E-mail: zhaoqi5000@vip.sohu.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Li Yu, E-mail: athen06@hotmail.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Fan Zhanming, E-mail: fanzm120@tom.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Ma Xiaohai, E-mail: maxi8238@gmail.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Lv Biao, E-mail: biao_lu2007@sina.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Yu Wei, E-mail: yuwei02@gmail.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China)

    2010-11-15

    Purpose: To explore feasibility of dual-source CT (DS-CT) prospective ECG-gated coronary angiography in patients with heart rate (HR) higher than 70 beat per minute (bpm), and evaluate image quality and radiation dose with comparison to retrospective ECG-gated spiral scan. Materials and methods: One hundred patients who underwent DS-CT coronary angiography (DS-CTCA) with mean HR higher than 70 bpm but below 110 bpm were enrolled in the study, 50 were scanned by adaptive sequential scan and another 50 were analyzed by retrospectively gated CT scan. The imaging quality of coronary artery segments in the two groups was evaluated using a four-point grading scale by two independent reviewers. Patient radiation dose was calculated by multiplying dose length product by conversion coefficient of 0.017. Results: There was no significant difference between the two groups for mean HR (p = 0.305), HR variability (p = 0.103), body mass index (p = 0.472), and scan length (p = 0.208). There was good agreement for image quality scoring between the two reviewers (Kappa = 0.72). Coronary evaluability of adaptive sequential scan was 99.7% (608 of 610 segments), while that of retrospective gated scan was 98.7% (614 of 622 segments), showing similar coronary evaluability (p = 0.061). Effective doses of adaptive sequential scan and retrospective gated scan were 5.1 {+-} 1.6 and 11.8 {+-} 4.5 mSv, respectively (p < 0.001), showing that adaptive sequential scan reduced radiation dose by 57% compared with that of retrospective gated scan. Conclusions: In patients with 70-110 bpm HR, DS-CTCA adaptive sequential scan shows similar image quality as retrospective ECG-gated spiral scan with 57% reduction of radiation dose.

  20. Physical and electrical properties of induced high-k ZrHfO crystallization with ZrN cap by high power impulse magnetron sputtering for metal-gate metal-insulator-semiconductor structures

    Science.gov (United States)

    Tsai, Jung-Ruey; Juan, Pi-Chun; Lin, Cheng-Li; Lin, Guo-Cheng

    2017-01-01

    Metal-gate TiN/ZrN/ZrHfO/p-Si metal-insulator-semiconductor (MIS) structures have been fabricated in this work. The physical and electrical properties were characterized. The crystallization of high-k ZrHfO thin-film is induced by high power impulse magnetron sputtering (HIPIMS) during the deposition of ZrN capping layer. The binding energies and depth profiles were investigated by X-ray photoelectron spectroscopy (XPS). It is found that Zr and Hf out-diffusion from high-k dielectric in samples with HIPIMS is lesser than those in samples with the conventional DC magnetron sputtering (DCMS). The dielectric constant which strongly relates to the tetragonal phase becomes higher and the flatband voltage shift shows smaller by using the HIPIMS method than by the conventional DCMS. The cation and anion vacancies have been investigated by the defect reaction model.

  1. Advanced insulated gate bipolar transistor gate drive

    Science.gov (United States)

    Short, James Evans; West, Shawn Michael; Fabean, Robert J.

    2009-08-04

    A gate drive for an insulated gate bipolar transistor (IGBT) includes a control and protection module coupled to a collector terminal of the IGBT, an optical communications module coupled to the control and protection module, a power supply module coupled to the control and protection module and an output power stage module with inputs coupled to the power supply module and the control and protection module, and outputs coupled to a gate terminal and an emitter terminal of the IGBT. The optical communications module is configured to send control signals to the control and protection module. The power supply module is configured to distribute inputted power to the control and protection module. The control and protection module outputs on/off, soft turn-off and/or soft turn-on signals to the output power stage module, which, in turn, supplies a current based on the signal(s) from the control and protection module for charging or discharging an input capacitance of the IGBT.

  2. Memory and negative-resistance effects in a strained metal-gate high-k n-type field-effect-transistor from 375 K down to 77 K

    Science.gov (United States)

    Gutiérrez-D, E. A.; Vega-G, V. H.; García-R, P. J.; Huerta-G, O. V.

    2016-12-01

    We introduce an experimental alternative way of looking into the charging and discharging mechanism inside a high-k stacked oxide of a metal-gate strained n-type Field-Effect-Transistor (nFET). This alternative way reproduces a memory and negative resistance effect by biasing the nFET device in a non-conventional way. This is achieved by forward-biasing the drain-bulk junction and by setting the gate electrode in a high-impedance mode. The produced negative resistance effect (NRE) has a controllable peak-to-valley current ratio (PVCR) that goes from about 3.0 up to a value of 5.5 at room temperature. The PVCR increases up to 8.35 at T = 225 K and reduces to 2.84 at T = 375 K in a linear trend. The memory effect is observed when the drain-bulk junction voltage is swept from low to high values and back from high to low values. From low to high forward drain-bulk bias the NRE shows up and vanishes when coming back from high to low forward drain-bulk bias. The NRE and memory effects are attributed to a coupled-gate oxide charging/discharging mechanism with an induced bipolar transistor action in the channel of the FET.

  3. Evaluation of three-dimensional navigator-gated whole heart MR coronary angiography: The importance of systolic imaging in subjects with high heart rates

    Energy Technology Data Exchange (ETDEWEB)

    Wu Yenwen [Department of Diagnostic Imaging, Kyoto University Graduate School of Medicine, 54 Shogoinkawahara-cho, Sakyo-ku, Kyoto 606-8507 (Japan); Tadamura, Eiji [Department of Diagnostic Imaging, Kyoto University Graduate School of Medicine, 54 Shogoinkawahara-cho, Sakyo-ku, Kyoto 606-8507 (Japan)]. E-mail: et@kuhp.kyoto-u.ac.jp; Yamamuro, Masaki [Department of Diagnostic Imaging, Kyoto University Graduate School of Medicine, 54 Shogoinkawahara-cho, Sakyo-ku, Kyoto 606-8507 (Japan); Kanao, Shotaro [Department of Diagnostic Imaging, Kyoto University Graduate School of Medicine, 54 Shogoinkawahara-cho, Sakyo-ku, Kyoto 606-8507 (Japan); Nakayama, Kazuki [Department of Radiology, Sakazaki Clinic, 11 Nishinokyoshimoai-cho, Nakagyo-ku, Kyoto 604-8436 (Japan); Togashi, Kaori [Department of Diagnostic Imaging, Kyoto University Graduate School of Medicine, 54 Shogoinkawahara-cho, Sakyo-ku, Kyoto 606-8507 (Japan)

    2007-01-15

    Purpose: To evaluate the influence of heart rate (HR) on magnetic resonance coronary angiography (MRCA) image quality in diastolic and systolic phases. Materials and methods: Twenty-seven healthy volunteers (9 men; 33 {+-} 9 years, HR 53-110 bpm), were evaluated with the electrocardiography and three-dimensional navigator-gating MRCA in a 1.5-T MR scanner (Avanto, Siemens) in diastolic and systolic phases (steady-state free precession; TR/TE/flip angle = 3.2 ms/1.6 ms/90{sup o}). The timing of scanning was individually adapted to the cardiac rest periods obtained in the prescanning, by visually identifying when the movement of right coronary artery was minimized during diastole and systole. Images of two phases were side-by-side compared on a four-point scale (from 1 = poor to 4 = excellent visibility; score of 3 or 4 as diagnostic). Results: Of 13 subjects with HR {<=}65 bpm (low HR group, mean 59.8 {+-} 4.9 bpm, range 53-65), the image quality scores were significantly better than that with higher heart rates (73.9 {+-} 9.0 bpm, range 68-110) in diastolic MRCA. The image quality was significantly improved during systole in high HR group. Overall, 91.3% of low HR group had MRCA image of diagnostic quality acquired at diastole, while 88.3% of high HR group had diagnostic images at systole by segmental analysis (p = NS). Conclusions: MRCA at systole offered superior quality in patients with high heart rates.

  4. Leakage current mechanisms of ultrathin high-k Er{sub 2}O{sub 3} gate dielectric film

    Energy Technology Data Exchange (ETDEWEB)

    Wu Deqi; Yao Jincheng; Zhao Hongsheng; Chang Aimin; Li Feng, E-mail: changam@ms.xjb.ac.c [Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830011 (China)

    2009-10-15

    A series of high dielectric material Er{sub 2}O{sub 3} thin films with different thicknesses were deposited on p-type Si (100) substrate by pulse laser deposition at different temperatures. Phase structures of the films were determined by means of X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). Leakage current density was measured with an HP4142B semiconductor parameter analyzer. The XRD and HRTEM results reveal that Er{sub 2}O{sub 3} thin films deposited below 400 {sup 0}C are amorphous, while films deposited from 400 to 840 {sup 0} are well crystallized with (111)-preferential crystallographic orientation. I-V curves show that, for ultrathin crystalline Er{sub 2}O{sub 3} films, the leakage current density increases by almost one order of magnitude from 6.20 x 10{sup -5} to 6.56 x 10{sup -4} A/cm{sup 2}, when the film thickness decreases by only 1.9 nm from 5.7 to 3.8 nm. However the leakage current density of ultrathin amorphous Er{sub 2}O{sub 3} films with a thickness of 3.8 nm is only 1.73 x 10{sup -5} A/cm{sup 2}. Finally, analysis of leakage current density showed that leakage of ultrathin Er{sub 2}O{sub 3} films at high field is mainly caused by Fowler-Nordheim tunneling, and the large leakage of ultrathin crystalline Er{sub 2}O{sub 3} films could arise from impurity defects at the grain boundary.

  5. Probing Dense Sprays with Gated, Picosecond, Digital Particle Field Holography

    Directory of Open Access Journals (Sweden)

    James Trolinger

    2011-12-01

    Full Text Available This paper describes work that demonstrated the feasibility of producing a gated digital holography system that is capable of producing high-resolution images of three-dimensional particle and structure details deep within dense particle fields of a spray. We developed a gated picosecond digital holocamera, using optical Kerr cell gating, to demonstrate features of gated digital holography that make it an exceptional candidate for this application. The Kerr cell gate shuttered the camera after the initial burst of ballistic and snake photons had been recorded, suppressing longer path, multiple scattered illumination. By starting with a CW laser without gating and then incorporating a picosecond laser and an optical Kerr gate, we were able to assess the imaging quality of the gated holograms, and determine improvement gained by gating. We produced high quality images of 50–200 μm diameter particles, hairs and USAF resolution charts from digital holograms recorded through turbid media where more than 98% of the light was scattered from the field. The system can gate pulses as short as 3 mm in pathlength (10 ps, enabling image-improving features of the system. The experiments lead us to the conclusion that this method has an excellent capability as a diagnostics tool in dense spray combustion research.

  6. Field-Induced Defect Morphology in Ni-gate AlGaN/GaN High Electron Mobility Transistors

    Science.gov (United States)

    2013-07-10

    mobility transistors. VC 2013 AIP Publishing LLC. [http://dx.doi.org/10.1063/1.4813535] AlGaN/ GaN high electron mobility transistors ( HEMTs ) remain...interactions could enhance the reliability of AlGaN/ GaN HEMTs by circumventing the defect formation conditions and preventing device degradation...AlGaN/ GaN HEMTs used for this work were all grown on the same semi-insulating 6H-SiC substrate and received the same processing. An AlN nucleation layer

  7. Gating a ferromagnetic semiconductor

    Science.gov (United States)

    Bove, A.; Altomare, F.; Kundtz, N.; Chang, A. M.; Cho, Y. J.; Liu, X.; Furdyna, J.

    2007-03-01

    Ferromagnetic semiconductors have the potential of revolutionizing the way current electronic devices work: more so, because they are compatible with current fabrication lines and can easily be integrated with today's technology. Particular interest lies in III-V Diluted Magnetic Semiconductor (DMS), where the ferromagnetism is hole-mediated and the Curie temperature can therefore be tuned by changing the concentration of free carriers. In these systems, most of the effort is currently applied toward the fabrication of devices working at room-temperature: this implies high carrier density accompanied by low mobility and short mean free path. We will report our results for a ferromagnetic 2DHG system with low carrier density (˜3.4E12 cm-2) and mobility (˜ 1000 cm^2/(Vs)), and we will discuss the effects of local gating in light of possible applications to the fabrication of ferromagnetic quantum dots. T. Dietl et al., Phys. Rev. B 63, 195205 (2001). H. Ohno et al., Nature 408, 944 (2000)

  8. A Novel Design of Half Subtractor using Reversible Feynman Gate in Quantum Dot cellular Automata

    Directory of Open Access Journals (Sweden)

    Rubina Akter

    2014-12-01

    Full Text Available Quantum Dot cellular Automata (QCA is an emerging, promising alternative to CMOS technology that performs its task by encoding binary information on electronic charge configuration of a cell. All circuit based on QCA has an advantages of high speed, high parallel processing, high integrityand low power consumption. Reversible logic gates are the leading part in Quantum Dot cellular Automata. Reversible logic gates have an extensive feature that does not lose information. In this paper, we present a novel architecture of half subtractor gate design by reversible Feynman gate. This circuit is designedbased on QCA logic gates such as QCA majority voter gate, majority AND gate, majority OR gate and inverter gate. This circuit will provide an effective working efficiency on computational units of the digital circuit system.

  9. Obesogenic dietary intake in families with 1-year-old infants at high and low obesity risk based on parental weight status: baseline data from a longitudinal intervention (Early STOPP)

    OpenAIRE

    Svensson, Viktoria; Sobko, Tanja; Ek, Anna; Forssén, Michaela; Ekbom, Kerstin; Johansson, Elin; Nowicka, Paulina; Westerståhl, Maria; Riserus, Ulf; Marcus, Claude

    2015-01-01

    Purpose To compare dietary intake in 1-year-old infants and their parents between families with high and low obesity risk, and to explore associations between infant dietary intake and relative weight. Methods Baseline analyses of 1-year-old infants (n = 193) and their parents participating in a longitudinal obesity intervention (Early STOPP) were carried out. Dietary intake and diet quality indicators were compared between high- and low-risk families, where obesity risk was based on parental...

  10. Process optimizations to recessed e-SiGe source/drain for performance enhancement in 22 nm all-last high-k/metal-gate pMOSFETs

    Science.gov (United States)

    Qin, Changliang; Wang, Guilei; Hong, Peizhen; Liu, Jinbiao; Yin, Huaxiang; Yin, Haizhou; Ma, Xiaolong; Cui, Hushan; Lu, Yihong; Meng, Lingkuan; Xiang, Jinjuan; Zhong, Huicai; Zhu, Huilong; Xu, Qiuxia; Li, Junfeng; Yan, Jian; Zhao, Chao; Radamson, Henry H.

    2016-09-01

    In this paper, the technology of recessed embedded SiGe (e-SiGe) source/drain (S/D) module is optimized for the performance enhancement in 22 nm all-last high-k/metal-gate (HK/MG) pMOSFETs. Different Si recess-etch techniques were applied in S/D regions to increase the strain in the channel and subsequently, improve the performance of transistors. A new recess-etch method consists of a two-step etch method is proposed. This process is an initial anisotropic etch for the formation of shallow trench followed by a final isotropic etch. By introducing the definition of the upper edge distance (D) between the recessed S/D region and the channel region, the process advantage of the new approach is clearly presented. It decreases the value of D than those by conventional one-step isotropic or anisotropic etch of Si. Therefore, the series resistance is reduced and the channel strain is increased, which confirmed by the simulation results. The physical reason of D reducing is analyzed in brief. Applying this recess design, the implant conditions for S/D extension (SDE) are also optimized by using a two-step implantation of BF2 in SiGe layers. The overlap space between doping junction and channel region has great effect on the device's performance. The designed implantation profile decreases the overlap space while keeps a shallow junction depth for a controllable short channel effect. The channel resistance as well as the transfer ID-VG curves varying with different process conditions are demonstrated. It shows the drive current of the device with the optimized SDE implant condition and Si recess-etch process is obviously improved. The change trend of on-off current distributions extracted from a series of devices confirmed the conclusions. This study provides a useful guideline for developing high performance strained PMOS SiGe technology.

  11. Molecular gate keepers succumb to gene aberrations in colorectal cancer in Kashmiri population, revealing a high incidence area

    Directory of Open Access Journals (Sweden)

    Sameer A

    2009-01-01

    Full Text Available Background/Aim: Colorectal cancer (CRC is one of the leading malignancies worldwide and has been reported to show geographical variation in its incidence, even within areas of ethnic homogeneity. The aim of this study was to identify p53 and K-ras gene mutations in CRC patients in a Kashmiri population, and to assess whether these mutations are linked with clinicopathological parameters. Materials and Methods: Paired tumor and normal tissue samples from a consecutive series of 53 patients undergoing resective surgery for CRC were prospectively studied for p53 and K-ras gene mutations by PCR/single strand conformation polymorphism (SSCP. Results: Less than half (45%, 19/42 of the patients presented mutations in the p53 gene. Twenty eight mutations were found in the p53 gene, which comprised of 23 substitutions (17 transitions + 6 transversions, and five insertions. The 23 substitutions constituted 18 missense mutations, two nonsense mutations, and three silent mutations. Of the 28 mutations (7.14% observed in this study, 2 were not previously reported for CRC samples and were identified as novel p53 mutations. A few patients (22.64%, 12/53 presented with mutations in K-ras, constituting 13 missense mutations, out of which 11 were G→A transitions, one was a G→C transversion, and one a G→T transversion. More than half (61.5% of the mutations occurred in codon 12 whereas a few (38.5% occurred in codon 13. One tumor contained missense mutations in both codons. Comparison of the mutation profiles of our patients with those of other ethnic populations and regions reflected both differences and similarities, indicating co-exposure to a unique set of risk factors. Conclusion: Mutations of the p53 and K-ras genes are some of the most common genetic changes in the development of human CRC. The high frequency of p53 gene mutations implicates p53 as a predominant factor for CRC in the high-risk ethnic Kashmiri population.

  12. The effect of vernal solar UV radiation on serum 25-hydroxyvitamin D concentration depends on the baseline level: observations from a high latitude in Finland.

    Science.gov (United States)

    Karppinen, Toni; Ala-Houhala, Meri; Ylianttila, Lasse; Kautiainen, Hannu; Lakkala, Kaisa; Hannula, Henna-Reetta; Turunen, Esa; Viljakainen, Heli; Reunala, Timo; Snellman, Erna

    2017-01-01

    Humans obtain vitamin D from conversion of 7-dehydrocholesterol in the skin by ultraviolet B (UVB) radiation or from dietary sources. As the radiation level is insufficient in winter, vitamin D deficiency is common at higher latitudes. We assessed whether vernal solar UVB radiation at latitudes 61°N and 67°N in Finland has an impact on serum 25-hydroxyvitamin D [S-25(OH)D] concentrations. Twenty-seven healthy volunteers participated in outdoor activities in snow-covered terrain for 4-10 days in March or April, with their face and hands sun-exposed. The personal UVB doses and S-25(OH)D levels were monitored. A mean UVB dose of 11.8 standard erythema doses (SED) was received during an average of 12.3 outdoor hours. The mean S-25(OH)D concentration in subjects with a baseline concentration below 90.0 nmol/L (n=13) increased significantly, by 6.0 nmol/L from an initial mean of 62.4 nmol/L (pD levels in subjects with a baseline level below 90 nmol/L but not in those with higher levels.

  13. Associated risk factors for silent cerebral infarcts in sickle cell anemia: low baseline hemoglobin, sex, and relative high systolic blood pressure.

    Science.gov (United States)

    DeBaun, Michael R; Sarnaik, Sharada A; Rodeghier, Mark J; Minniti, Caterina P; Howard, Thomas H; Iyer, Rathi V; Inusa, Baba; Telfer, Paul T; Kirby-Allen, Melanie; Quinn, Charles T; Bernaudin, Françoise; Airewele, Gladstone; Woods, Gerald M; Panepinto, Julie Ann; Fuh, Beng; Kwiatkowski, Janet K; King, Allison A; Rhodes, Melissa M; Thompson, Alexis A; Heiny, Mark E; Redding-Lallinger, Rupa C; Kirkham, Fenella J; Sabio, Hernan; Gonzalez, Corina E; Saccente, Suzanne L; Kalinyak, Karen A; Strouse, John J; Fixler, Jason M; Gordon, Mae O; Miller, J Phillip; Noetzel, Michael J; Ichord, Rebecca N; Casella, James F

    2012-04-19

    The most common form of neurologic injury in sickle cell anemia (SCA) is silent cerebral infarction (SCI). In the Silent Cerebral Infarct Multi-Center Clinical Trial, we sought to identify risk factors associated with SCI. In this cross-sectional study, we evaluated the clinical history and baseline laboratory values and performed magnetic resonance imaging of the brain in participants with SCA (HbSS or HbSβ° thalassemia) between the ages of 5 and 15 years with no history of overt stroke or seizures. Neuroradiology and neurology committees adjudicated the presence of SCI. SCIs were diagnosed in 30.8% (251 of 814) participants who completed all evaluations and had valid data on all prespecified demographic and clinical covariates. The mean age of the participants was 9.1 years, with 413 males (50.7%). In a multivariable logistic regression analysis, lower baseline hemoglobin concentration (P blood pressure (P = .018), and male sex (P = .030) were statistically significantly associated with an increased risk of an SCI. Hemoglobin concentration and systolic blood pressure are risk factors for SCI in children with SCA and may be therapeutic targets for decreasing the risk of SCI. This study is registered at www.clinicaltrials.gov as #NCT00072761.

  14. Long Baseline Neutrino Experiments

    Science.gov (United States)

    Mezzetto, Mauro

    2016-05-01

    Following the discovery of neutrino oscillations by the Super-Kamiokande collaboration, recently awarded with the Nobel Prize, two generations of long baseline experiments had been setup to further study neutrino oscillations. The first generation experiments, K2K in Japan, Minos in the States and Opera in Europe, focused in confirming the Super-Kamiokande result, improving the precision with which oscillation parameters had been measured and demonstrating the ντ appearance process. Second generation experiments, T2K in Japan and very recently NOνA in the States, went further, being optimized to look for genuine three neutrino phenomena like non-zero values of θ13 and first glimpses to leptonic CP violation (LCPV) and neutrino mass ordering (NMO). The discovery of leptonic CP violation will require third generation setups, at the moment two strong proposals are ongoing, Dune in the States and Hyper-Kamiokande in Japan. This review will focus a little more in these future initiatives.

  15. Biofuels Baseline 2008

    Energy Technology Data Exchange (ETDEWEB)

    Hamelinck, C.; Koper, M.; Berndes, G.; Englund, O.; Diaz-Chavez, R.; Kunen, E.; Walden, D.

    2011-10-15

    The European Union is promoting the use of biofuels and other renewable energy in transport. In April 2009, the Renewable Energy Directive (2009/28/EC) was adopted that set a 10% target for renewable energy in transport in 2020. The directive sets several requirements to the sustainability of biofuels marketed in the frame of the Directive. The Commission is required to report to the European Parliament on a regular basis on a range of sustainability impacts resulting from the use of biofuels in the EU. This report serves as a baseline of information for regular monitoring on the impacts of the Directive. Chapter 2 discusses the EU biofuels market, the production and consumption of biofuels and international trade. It is derived where the feedstock for EU consumed biofuels originally come from. Chapter 3 discusses the biofuel policy framework in the EU and major third countries of supply. It looks at various policy aspects that are relevant to comply with the EU sustainability requirements. Chapter 4 discusses the environmental and social sustainability aspects associated with EU biofuels and their feedstock. Chapter 5 discusses the macro-economic effects that indirectly result from increased EU biofuels consumption, on commodity prices and land use. Chapter 6 presents country factsheets for main third countries that supplied biofuels to the EU market in 2008.

  16. Methodology of Resonant Equiangular Composite Quantum Gates

    Science.gov (United States)

    Low, Guang Hao; Yoder, Theodore J.; Chuang, Isaac L.

    2016-10-01

    The creation of composite quantum gates that implement quantum response functions U ^(θ ) dependent on some parameter of interest θ is often more of an art than a science. Through inspired design, a sequence of L primitive gates also depending on θ can engineer a highly nontrivial U ^ (θ ) that enables myriad precision metrology, spectroscopy, and control techniques. However, discovering new, useful examples of U ^(θ ) requires great intuition to perceive the possibilities, and often brute force to find optimal implementations. We present a systematic and efficient methodology for composite gate design of arbitrary length, where phase-controlled primitive gates all rotating by θ act on a single spin. We fully characterize the realizable family of U ^ (θ ) , provide an efficient algorithm that decomposes a choice of U ^ (θ ) into its shortest sequence of gates, and show how to efficiently choose an achievable U ^(θ ) that, for fixed L , is an optimal approximation to objective functions on its quadratures. A strong connection is forged with classical discrete-time signal processing, allowing us to swiftly construct, as examples, compensated gates with optimal bandwidth that implement arbitrary single-spin rotations with subwavelength spatial selectivity.

  17. Radiation-Insensitive Inverse Majority Gates

    Science.gov (United States)

    Manohara, Harish; Mojarradi, Mohammad

    2008-01-01

    To help satisfy a need for high-density logic circuits insensitive to radiation, it has been proposed to realize inverse majority gates as microscopic vacuum electronic devices. In comparison with solid-state electronic devices ordinarily used in logic circuits, vacuum electronic devices are inherently much less adversely affected by radiation and extreme temperatures. The proposed development would involve state-of-the-art micromachining and recent advances in the fabrication of carbon-nanotube-based field emitters. A representative three-input inverse majority gate would be a monolithic, integrated structure that would include three gate electrodes, six bundles of carbon nanotubes (serving as electron emitters) at suitable positions between the gate electrodes, and an overhanging anode. The bundles of carbon nanotubes would be grown on degenerately doped silicon substrates that would be parts of the monolithic structure. The gate electrodes would be fabricated as parts of the monolithic structure by means of a double-silicon-on-insulator process developed at NASA's Jet Propulsion Laboratory. The tops of the bundles of carbon nanotubes would lie below the plane of the tops of the gate electrodes. The particular choice of shapes, dimensions, and relative positions of the electrodes and bundles of carbon nanotubes would provide for both field emission of electrons from the bundles of carbon nanotubes and control of the electron current to obtain the inverse majority function, which is described in the paper.

  18. Immunosuppressive cytokine Interleukin-10 (IL-10) is up-regulated in high-grade CIN but not associated with high-risk human papillomavirus (HPV) at baseline, outcomes of HR-HPV infections or incident CIN in the LAMS cohort.

    Science.gov (United States)

    Syrjänen, Stina; Naud, Paulo; Sarian, Luis; Derchain, Sophie; Roteli-Martins, Cecilia; Longatto-Filho, Adhemar; Tatti, Silvio; Branca, Margherita; Erzen, Mojca; Hammes, L S; Costa, S; Syrjänen, Kari

    2009-12-01

    Bypassing the local immunological defense reactions in the cervix is one of the prerequisites for human papillomaviruses (HPV) infections to progress to intraepithelial neoplasia (CIN). The role of potent immunosuppressive cytokines, e.g., interleukin-10 (IL-10), depressing these local virus-specific immunological responses is incompletely studied. To assess, whether IL-10 expression in cervical HPV lesions has any implications in the outcome of HPV infections or disease progression to CIN. Baseline cervical biopsies from 225 women of the LAMS study sub-cohort were analyzed for IL-10 expression using immunohistochemistry, to assess its associations with CIN grade, and high-risk HPV (HR-HPV) at baseline, as well as in predicting outcomes of HR-HPV infections, and development of incident CIN1+ and CIN2+ in this longitudinal setting. Expression of IL-10 in cervical lesions was up-regulated most often in high-grade CIN, and IL-10 over-expression retained its value as independent predictor of CIN2+ (odds ratio (OR) = 4.92) and CIN3+ (OR = 7.51) also in multivariate model, including HR-HPV and several known covariates of IL-10 expression. Up-regulation was not related to HR-HPV detection, and showed no relationship to HR-HPV viral loads. Using longitudinal predictive indicators (SE, SP, PPV, NPV), IL-10 expression was of no value in predicting (1) the outcomes of HR-HPV infections, or (2) the surrogate endpoints (incident CIN1+, CIN2+) of progressive disease. IL-10 over-expression (along with HR-HPV) was one of the independent covariates of CIN2/3. This immunosuppressive cytokine might play an important role in creating a microenvironment that favors progressive cervical disease and immune evasion by HR-HPV.

  19. Low-voltage polymer thin-film transistors with high-k HfTiO gate dielectric annealed in NH3 or N2

    OpenAIRE

    Choi, HW; Lai, PT; Xu, JP; Deng, LF; Liu, YR

    2009-01-01

    OTFTs with P3HT as organic semiconductor and HfTiO as gate dielectric have been studied in this work. The HfTiO dielectric film was prepared by RF sputtering of Hf and DC sputtering of Ti at room temperature. Subsequently, the dielectric film was annealed in an NH3 or N2 ambient at 200 °C. Then a layer of OTS was deposited by spin-coating method to improve the surface characteristics of the gate dielectric. Afterwards, P3HT was deposited by spin-coating method. The OTFTs were characterized by...

  20. High-pass filters and baseline correction in M/EEG analysis. Commentary on: "How inappropriate high-pass filters can produce artefacts and incorrect conclusions in ERP studies of language and cognition".

    Science.gov (United States)

    Maess, Burkhard; Schröger, Erich; Widmann, Andreas

    2016-06-15

    Tanner et al. (2015. Psychophysiology, 52(8), 1009. doi: 10.1111/psyp.12437) convincingly demonstrate how a late deflection like the N400 or the P600 is reflected into both earlier and later latencies by the application of high-pass filters with cutoff frequencies higher than 0.1Hz. It nicely underlines the importance of test-wise application of filters with different parameters to electrophysiological data to identify such unwanted filter effects. In general, we agree with their approach and conclusions, particularly with the notions that the application of a high-pass filter is reasonable if it improves the signal-to-noise ratio (SNR) of the signal of interest, and that low frequency signals may carry important information. However, we disagree in two aspects: First, the test data of Tanner et al. are not optimally suited to demonstrate the benefits of high-pass filtering as they are only minimally contaminated by low frequency noise, and second, the standard baseline correction for particular applications in M/EEG data analysis should be replaced with high-pass filtering-as recommended by Widmann et al. (2015. J Neurosci Methods, 250, 46. doi: 10.1016/j.jneumeth.2014.08.002). Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Role of glycine residues highly conserved in the S2-S3 linkers of domains I and II of voltage-gated calcium channel alpha(1) subunits.

    Science.gov (United States)

    Teng, Jinfeng; Iida, Kazuko; Ito, Masanori; Izumi-Nakaseko, Hiroko; Kojima, Itaru; Adachi-Akahane, Satomi; Iida, Hidetoshi

    2010-05-01

    The pore-forming component of voltage-gated calcium channels, alpha(1) subunit, contains four structurally conserved domains (I-IV), each of which contains six transmembrane segments (S1-S6). We have shown previously that a Gly residue in the S2-S3 linker of domain III is completely conserved from yeasts to humans and important for channel activity. The Gly residues in the S2-S3 linkers of domains I and II, which correspond positionally to the Gly in the S2-S3 linker of domain III, are also highly conserved. Here, we investigated the role of the Gly residues in the S2-S3 linkers of domains I and II of Ca(v)1.2. Each of the Gly residues was replaced with Glu or Gln to produce mutant Ca(v)1.2s; G182E, G182Q, G579E, G579Q, and the resulting mutants were transfected into BHK6 cells. Whole-cell patch-clamp recordings showed that current-voltage relationships of the four mutants were the same as those of wild-type Ca(v)1.2. However, G182E and G182Q showed significantly smaller current densities because of mislocalization of the mutant proteins, suggesting that Gly(182) in domain I is involved in the membrane trafficking or surface expression of alpha(1) subunit. On the other hand, G579E showed a slower voltage-dependent current inactivation (VDI) compared to Ca(v)1.2, although G579Q showed a normal VDI, implying that Gly(579) in domain II is involved in the regulation of VDI and that the incorporation of a negative charge alters the VDI kinetics. Our findings indicate that the two conserved Gly residues are important for alpha(1) subunit to become functional.

  2. High-resolution 3D non-contrast-enhanced, ECG-gated, multi-step MR angiography of the lower extremities: Comparison with contrast-enhanced MR angiography

    Energy Technology Data Exchange (ETDEWEB)

    Mohrs, Oliver K. [University of Heidelberg, Department of Diagnostic and Interventional Radiology, Heidelberg (Germany); Darmstadt Radiology, Department of Cardiovascular Imaging at Alice-Hospital, Darmstadt (Germany); Petersen, Steffen E. [The London Chest Hospital, Centre for Advanced Cardiovascular Imaging, William Harvey Research Institute, Barts and The London NIHR Biomedical Research Unit, London (United Kingdom); Heidt, Martin C. [Cardiovascular Center Darmstadt, Darmstadt (Germany); Schulze, Thomas; Schmitt, Peter [Siemens AG, Healthcare Sector, MR Application and Workflow Development, Erlangen (Germany); Bergemann, Sabine [Darmstadt Radiology, Department of Cardiovascular Imaging at Alice-Hospital, Darmstadt (Germany); Kauczor, Hans-Ulrich [University of Heidelberg, Department of Diagnostic and Interventional Radiology, Heidelberg (Germany)

    2011-02-15

    To determine the diagnostic value of non-contrast-enhanced, 3D-high-resolution, ECG-gated, multi-step MR angiography (non-ceMRA) of the lower extremities using a modified turbo-spin-echo technique in comparison to 1.0-molar contrast-enhanced MR angiography (ceMRA) in patients with suspected peripheral vascular disease (PVD). Fifty consecutive patients underwent non-ceMRA before ceMRA within the same session. We assessed examination time, image quality, localisation and severity of stenosis. Examination time was shorter for ceMRA (12 {+-} 4 min) compared with non-ceMRA (28 {+-} 6 min, p < 0.001). The image quality of the aorta-iliac, femoral and combined popliteal and lower leg arteries was inferior for non-ceMRA (2.8 {+-} 0.8/3.3 {+-} 0.8/3.3 {+-} 0.9) versus ceMRA (4.7 {+-} 0.8/4.8 {+-} 0.6/4.8 {+-} 0.7) on a 5-point scale with 5 for maximum quality (p < 0.01). CeMRA offered more assessable data sets than non-ceMRA (98% vs. 90%). For detecting stenosis >50% or occlusions of pelvic and femoral arteries using non-ceMRA the sensitivity, specificity, positive and negative predictive values were 94%, 86%, 67% and 98% and for popliteal and lower leg arteries 93%, 87%, 69% and 98%, respectively. We demonstrated that 3D non-ceMRA represents a very promising technique in patients with lower extremities PVD and could be used as an alternative if gadolinium-based contrast agents cannot be administered. (orig.)

  3. The effect of vernal solar UV radiation on serum 25-hydroxyvitamin D concentration depends on the baseline level: observations from a high latitude in Finland

    Science.gov (United States)

    Karppinen, Toni; Ala-Houhala, Meri; Ylianttila, Lasse; Kautiainen, Hannu; Lakkala, Kaisa; Hannula, Henna-Reetta; Turunen, Esa; Viljakainen, Heli; Reunala, Timo; Snellman, Erna

    2017-01-01

    ABSTRACT Humans obtain vitamin D from conversion of 7-dehydrocholesterol in the skin by ultraviolet B (UVB) radiation or from dietary sources. As the radiation level is insufficient in winter, vitamin D deficiency is common at higher latitudes. We assessed whether vernal solar UVB radiation at latitudes 61°N and 67°N in Finland has an impact on serum 25-hydroxyvitamin D [S-25(OH)D] concentrations. Twenty-seven healthy volunteers participated in outdoor activities in snow-covered terrain for 4–10 days in March or April, with their face and hands sun-exposed. The personal UVB doses and S-25(OH)D levels were monitored. A mean UVB dose of 11.8 standard erythema doses (SED) was received during an average of 12.3 outdoor hours. The mean S-25(OH)D concentration in subjects with a baseline concentration below 90.0 nmol/L (n=13) increased significantly, by 6.0 nmol/L from an initial mean of 62.4 nmol/L (p<0.001), whereas in those with a basal concentration above 90.0 nmol/L (n=12) it decreased significantly, by 6.7 nmol/L from a mean of 116.9 nmol/L (p<0.01). To conclude, only 7% of total body surface area was exposed to vernal sunlight and this was capable of increasing S-25(OH)D levels in subjects with a baseline level below 90 nmol/L but not in those with higher levels.

  4. The Gates at Pipe Spring National Monument, Arizona (gates)

    Data.gov (United States)

    National Park Service, Department of the Interior — This is an Arc/Info coverage consisting of 7 points representing gates at Pipe Spring National Monument, Arizona. The gates were collected by a Trimble GeoXT GPS...

  5. Amplifying genetic logic gates.

    Science.gov (United States)

    Bonnet, Jerome; Yin, Peter; Ortiz, Monica E; Subsoontorn, Pakpoom; Endy, Drew

    2013-05-03

    Organisms must process information encoded via developmental and environmental signals to survive and reproduce. Researchers have also engineered synthetic genetic logic to realize simpler, independent control of biological processes. We developed a three-terminal device architecture, termed the transcriptor, that uses bacteriophage serine integrases to control the flow of RNA polymerase along DNA. Integrase-mediated inversion or deletion of DNA encoding transcription terminators or a promoter modulates transcription rates. We realized permanent amplifying AND, NAND, OR, XOR, NOR, and XNOR gates actuated across common control signal ranges and sequential logic supporting autonomous cell-cell communication of DNA encoding distinct logic-gate states. The single-layer digital logic architecture developed here enables engineering of amplifying logic gates to control transcription rates within and across diverse organisms.

  6. Highly reliable top-gated thin-film transistor memory with semiconducting, tunneling, charge-trapping, and blocking layers all of flexible polymers.

    Science.gov (United States)

    Wang, Wei; Hwang, Sun Kak; Kim, Kang Lib; Lee, Ju Han; Cho, Suk Man; Park, Cheolmin

    2015-05-27

    The core components of a floating-gate organic thin-film transistor nonvolatile memory (OTFT-NVM) include the semiconducting channel layer, tunneling layer, floating-gate layer, and blocking layer, besides three terminal electrodes. In this study, we demonstrated OTFT-NVMs with all four constituent layers made of polymers based on consecutive spin-coating. Ambipolar charges injected and trapped in a polymer electret charge-controlling layer upon gate program and erase field successfully allowed for reliable bistable channel current levels at zero gate voltage. We have observed that the memory performance, in particular the reliability of a device, significantly depends upon the thickness of both blocking and tunneling layers, and with an optimized layer thickness and materials selection, our device exhibits a memory window of 15.4 V, on/off current ratio of 2 × 10(4), read and write endurance cycles over 100, and time-dependent data retention of 10(8) s, even when fabricated on a mechanically flexible plastic substrate.

  7. Analysis of polling system with high priority queue using twice gated service%中心队列二次门限服务的轮询系统分析

    Institute of Scientific and Technical Information of China (English)

    王明贵; 赵东风; 丁洪伟; 赖裕平

    2009-01-01

    According to the embedded Markov chain theory and the generating function,the paper analyzes a priority queue polling system in discrete time.It is introduced a service that the common queue use gated service and the high priority queue use twice gated service,and the average queue length and average polling period is explicidy obtained.%采用嵌入Markov链和概率母函数的方法时门限服务优先级排队系统进行分析,提出普通队列和高优先级队列分别采用基本门限和二级门限的服务机制,得出了平均排队队长和平均查询周期的解析式.

  8. Engineering Customized TALENs Using the Platinum Gate TALEN Kit.

    Science.gov (United States)

    Sakuma, Tetsushi; Yamamoto, Takashi

    2016-01-01

    Among various strategies for constructing customized transcription activator-like effector nucleases (TALENs), the Golden Gate assembly is the most widely used and most characterized method. The principle of Golden Gate assembly involves cycling reactions of digestion and ligation of multiple plasmids in a single tube, resulting in PCR-, fragmentation-, and purification-free concatemerization of DNA-binding repeats. Here, we describe the protocols for Golden Gate assembly-based TALEN construction using the Platinum Gate TALEN Kit, which allows generation of highly active Platinum TALENs.

  9. Statin use in adults at high risk of cardiovascular disease mortality: cross-sectional analysis of baseline data from The Irish Longitudinal Study on Ageing (TILDA).

    LENUS (Irish Health Repository)

    Murphy, Catriona

    2015-07-01

    This study aims to examine the extent to which statins are used by adults at high risk of cardiovascular disease (CVD) compared to European clinical guidelines. The high-risk groups examined are those with (1) known CVD, (2) known diabetes and (3) a high or very high risk (≥5%) of CVD mortality based on Systematic COronary Risk Evaluation (SCORE).

  10. Scanning Gate Spectroscopy on Nanoclusters

    OpenAIRE

    Gurevich, L.; Canali, L.; Kouwenhoven, L.P.

    1999-01-01

    A gated probe for scanning tunnelling microscopy (STM) has been developed. The probe extends normal STM operations by means of an additional electrode fabricated next to the tunnelling tip. The extra electrode does not make contact with the sample and can be used as a gate. We report on the recipe used for fabricating the tunnelling tip and the gate electrode on a silicon nitride cantilever. We demonstrate the functioning of the scanning gate probes by performing single-electron tunnelling sp...

  11. Risk Factors for Physical Domestic Violence in a High-Prevalence HIV Setting: Findings from Project Accept Baseline Data (HPTN-043).

    Science.gov (United States)

    Kevany, Sebastian; Woelk, Godfrey; Shade, Starley B; Kulich, Michal; Turan, Janet M; Chingono, Alfred; Morin, Stephen F

    2013-06-25

    Zimbabwe faces an acute generalized HIV/AIDS epidemic combined with rapidly deteriorating economic and political conditions, under which levels of domestic violence are on the rise. We aimed to determine possible demographic and behavioral factors associated with physical domestic violence in a rural setting in order to better inform both national and local domestic violence and HIV prevention policies. Using the Project Accept baseline data set, we selected demographic, socio-economic, and behavioral variables that might be associated with physical domestic violence based on a review of the literature. Univariate and multivariate analyses were carried out, and odds ratios (OR) were computed using logistic regression. Women reporting physical domestic violence were significantly more likely to report (i) a history of childhood domestic violence (OR=2.96, Peconomic status as measured by type of homestead (OR=1.4, P=0.04) than women who reported no experience of physical domestic violence. Married women were less likely to experience physical domestic violence than unmarried women (OR=0.65, P=0.011). Women at greatest risk of domestic violence include those with a personal history of violence or sexual abuse, multiple lifetime partners, and low or medium socio-economic status. Risk assessments and joint interventions for both domestic violence reduction and HIV prevention should target these population groups, which are effective both on the public health and global heath diplomacy levels.

  12. Polarimetric Observations of 15 Active Galactic Nuclei at High Frequencies: Jet Kinematics from Bimonthly Monitoring with the Very Long Baseline Array

    CERN Document Server

    Jorstad, S G; Lister, M L; Stirling, A M; Cawthorne, T V; Gear, W K; Gómez, J L; Stevens, J A; Smith, P S; Forster, J R; Gabuzda, D C; Robson, E I; Jorstad, Svetlana G.; Marscher, Alan P.; Lister, Matthew L.; Stirling, Alastair M.; Cawthorne, Timothy V.; Gear, Walter K.; Gomez, Jose L.; Stevens, Jason A.; Smith, Paul S.; Forster, James R.; Gabuzda, Denise C.

    2005-01-01

    We present total and polarized intensity images of 15 active galactic nuclei obtained with the Very Long Baseline Array at 7 mm at 17 epochs from 1998 March to 2001 April. At some epochs the images are accompanied by nearly simultaneous polarization measurements at 3 mm, 1.35/0.85 mm, and optical wavelengths. Here we analyze the 7 mm images to define the properties of the jets of two radio galaxies, five BL Lac objects, and eight quasars on angular scales $\\gtrsim 0.1$ milliarcseconds. We determine the apparent velocities of 109 features in the jets; for many of the features we derive Doppler factors using a new method based on comparison of timescale of decline in flux density with the light-travel time across the emitting region. This allows us to estimate the Lorentz factors, intrinsic brightness temperatures, and viewing angles of 77 superluminal knots, as well as the opening angle of the jet for each source. We analyze the derived physical parameters of the jets. In nine sources we detect statistically m...

  13. Stanford, Duke, Rice,... and Gates?

    Science.gov (United States)

    Carey, Kevin

    2009-01-01

    This article presents an open letter to Bill Gates. In his letter, the author suggests that Bill Gates should build a brand-new university, a great 21st-century institution of higher learning. This university will be unlike anything the world has ever seen. He asks Bill Gates not to stop helping existing colleges create the higher-education system…

  14. Stanford, Duke, Rice,... and Gates?

    Science.gov (United States)

    Carey, Kevin

    2009-01-01

    This article presents an open letter to Bill Gates. In his letter, the author suggests that Bill Gates should build a brand-new university, a great 21st-century institution of higher learning. This university will be unlike anything the world has ever seen. He asks Bill Gates not to stop helping existing colleges create the higher-education system…

  15. The four-gate transistor

    Science.gov (United States)

    Mojarradi, M. M.; Cristoveanu, S.; Allibert, F.; France, G.; Blalock, B.; Durfrene, B.

    2002-01-01

    The four-gate transistor or G4-FET combines MOSFET and JFET principles in a single SOI device. Experimental results reveal that each gate can modulate the drain current. Numerical simulations are presented to clarify the mechanisms of operation. The new device shows enhanced functionality, due to the combinatorial action of the four gates, and opens rather revolutionary applications.

  16. Modeling and estimation of process-induced stress in the nanowire field-effect-transistors (NW-FETs) on Insulator-on-Silicon substrates with high-k gate-dielectrics

    Science.gov (United States)

    Chatterjee, Sulagna; Chattopadhyay, Sanatan

    2016-10-01

    An analytical model including the simultaneous impact of lattice and thermo-elastic constant mismatch-induced stress in nanowires on Insulator-on-Silicon substrate is developed. It is used to calibrate the finite-element based software, ANSYS, which is subsequently employed to estimate process-induced stress in the sequential steps of NW-FET fabrication. The model considers crystal structures and orientations for both the nanowires and substrates. In-plane stress components along nanowire-axis are estimated for different radii and fractions of insertion. Nature of longitudinal stress is observed to change when inserted fraction of nanowires is changed. Effect of various high-k gate-dielectrics is also investigated. A longitudinal tensile stress of 2.4 GPa and compressive stress of 1.89 GPa have been obtained for NW-FETs with 1/4th and 3/4th insertions with La2O3 and TiO2 as the gate-dielectrics, respectively. Therefore, it is possible to achieve comparable values of electron and hole mobility in NW-FETs by judiciously choosing gate-dielectrics and fractional insertion of the nanowires.

  17. Risk factors for physical domestic violence in a high-prevalence HIV setting: findings from Project Accept baseline data (HPTN-043

    Directory of Open Access Journals (Sweden)

    Sebastian Kevany

    2013-07-01

    Full Text Available Zimbabwe faces an acute generalized HIV/AIDS epidemic combined with rapidly deteriorating economic and political conditions, under which levels of domestic violence are on the rise. We aimed to determine possible demographic and behavioral factors associated with physical domestic violence in a rural setting in order to better inform both national and local domestic violence and HIV prevention policies. Using the Project Accept baseline data set, we selected demographic, socio-economic, and behavioral variables that might be associated with physical domestic violence based on a review of the literature. Univariate and multivariate analyses were carried out, and odds ratios (OR were computed using logistic regression. Women reporting physical domestic violence were significantly more likely to report (i a history of childhood domestic violence (OR=2.96, P<0.001, (ii two or more lifetime partners (OR=1.94, P<0.001, (iii some form of sexual abuse as a child (OR=1.82, not significant, and (iv low or medium socio-economic status as measured by type of homestead (OR=1.4, P=0.04 than women who reported no experience of physical domestic violence. Married women were less likely to experience physical domestic violence than unmarried women (OR=0.65, P=0.011. Women at greatest risk of domestic violence include those with a personal history of violence or sexual abuse, multiple lifetime partners, and low or medium socio-economic status. Risk assessments and joint interventions for both domestic violence reduction and HIV prevention should target these population groups, which are effective both on the public health and global heath diplomacy levels.

  18. Biophysics, Pathophysiology and Pharmacology of Ion Channel Gating Pores

    Directory of Open Access Journals (Sweden)

    Adrien eMoreau

    2014-04-01

    Full Text Available Voltage sensor domain (VSDs are a feature of voltage gated ion channel (VGICs and voltage sensitive proteins. They are composed of four transmembrane (TM segments (S1 to S4. Currents leaking through VSDs are called omega or gating pore currents.Gating pores are caused by mutations of the highly conserved positively charged amino acids in the S4 segment that disrupt interactions between the S4 segment and the gating charge transfer center (GCTC. The GCTC separates the intracellular and extracellular water crevices. The disruption of S4–GCTC interactions allows these crevices to communicate and create a fast activating and non-inactivating alternative cation-selective permeation pathway of low conductance, or a gating pore.Gating pore currents have recently been shown to cause periodic paralysis phenotypes. There is also increasing evidence that gating pores are linked to several other familial diseases. For example, gating pores in Nav1.5 and Kv7.2 channels may underlie mixed arrhythmias associated with dilated cardiomyopathy (DCM phenotypes and peripheral nerve hyperexcitability (PNH respectively. There is little evidence for the existence of gating pore blockers. Moreover, it is known that a number of toxins bind to the VSD of a specific domain of Na+ channels. These toxins may thus modulate gating pore currents. This focus on the VSD motif opens up a new area of research centered on developing molecules to treat a number of cell excitability disorders such as epilepsy, cardiac arrhythmias, and pain.The purpose of the present review is to summarize existing knowledge of the pathophysiology, biophysics, and pharmacology of gating pore currents and to serve as a guide for future studies aimed at improving our understanding of gating pores and their pathophysiological roles.

  19. Focal overlap gating in velocity map imaging to achieve high signal-to-noise ratio in photo-ion pump-probe experiments

    Science.gov (United States)

    Shivaram, Niranjan; Champenois, Elio G.; Cryan, James P.; Wright, Travis; Wingard, Taylor; Belkacem, Ali

    2016-12-01

    We demonstrate a technique in velocity map imaging (VMI) that allows spatial gating of the laser focal overlap region in time resolved pump-probe experiments. This significantly enhances signal-to-noise ratio by eliminating background signal arising outside the region of spatial overlap of pump and probe beams. This enhancement is achieved by tilting the laser beams with respect to the surface of the VMI electrodes which creates a gradient in flight time for particles born at different points along the beam. By suitably pulsing our microchannel plate detector, we can select particles born only where the laser beams overlap. This spatial gating in velocity map imaging can benefit nearly all photo-ion pump-probe VMI experiments especially when extreme-ultraviolet light or X-rays are involved which produce large background signals on their own.

  20. Focal overlap gating in velocity map imaging to achieve high signal-to-noise ratio in photo-ion pump-probe experiments

    CERN Document Server

    Shivaram, Niranjan; Cryan, James P; Wright, Travis W; Wingard, Taylor; Belkacem, Ali

    2016-01-01

    We demonstrate a new technique in velocity map imaging (VMI) that allows spatial gating of the laser focal overlap region in time resolved pump-probe experiments. This significantly enhances signal-to-noise ratio by eliminating background signal arising outside the region of spatial overlap of pump and probe beams. This enhancement is achieved by tilting the laser beams with respect to the surface of the VMI electrodes which creates a gradient in flight time for particles born at different points along the beam. By suitably pulsing our microchannel plate detector, we can select particles born only where the laser beams overlap. This spatial gating in velocity map imaging can benefit nearly all photoion pump-probe VMI experiments especially when extreme-ultraviolet (XUV) light or X-rays are involved which produce large background signals on their own.

  1. SEMICONDUCTOR DEVICES: Double gate lateral IGBT on partial membrane

    Science.gov (United States)

    Xiaorong, Luo; Lei, Lei; Wei, Zhang; Bo, Zhang; Zhaoji, Li

    2010-02-01

    A new SOI LIGBT (lateral insulated-gate bipolar transistor) with cathode- and anode-gates on partial membrane is proposed. A low on-state resistance is achieved when a negative voltage is applied to the anode gate. In the blocking state, the cathode gate is shortened to the cathode and the anode gate is shortened to the anode, leading to a fast switching speed. Moreover, the removal of the partial silicon substrate under the drift region avoids collecting charges beneath the buried oxide, which releases potential lines below the membrane, yielding an enhanced breakdown voltage (BV). Furthermore, a high switching speed is obtained due to the absence of the drain-substrate capacitance. Lastly, a combination of uniformity and variation in lateral doping profiles helps to achieve a high BV and low special on-resistance. Compared with a conventional LIGBT, the proposed structure exhibits high current capability, low special on-resistance, and double the BV.

  2. Time-resolved dosimetric verification of respiratory-gated radiotherapy exposures using a high-resolution 2D ionisation chamber array.

    Science.gov (United States)

    King, R B; Agnew, C E; O'Connell, B F; Prise, K M; Hounsell, A R; McGarry, C K

    2016-08-07

    The aim of this work was to track and verify the delivery of respiratory-gated irradiations, performed with three versions of TrueBeam linac, using a novel phantom arrangement that combined the OCTAVIUS(®) SRS 1000 array with a moving platform. The platform was programmed to generate sinusoidal motion of the array. This motion was tracked using the real-time position management (RPM) system and four amplitude gating options were employed to interrupt MV beam delivery when the platform was not located within set limits. Time-resolved spatial information extracted from analysis of x-ray fluences measured by the array was compared to the programmed motion of the platform and to the trace recorded by the RPM system during the delivery of the x-ray field. Temporal data recorded by the phantom and the RPM system were validated against trajectory log files, recorded by the linac during the irradiation, as well as oscilloscope waveforms recorded from the linac target signal. Gamma analysis was employed to compare time-integrated 2D x-ray dose fluences with theoretical fluences derived from the probability density function for each of the gating settings applied, where gamma criteria of 2%/2 mm, 1%/1 mm and 0.5%/0.5 mm were used to evaluate the limitations of the RPM system. Excellent agreement was observed in the analysis of spatial information extracted from the SRS 1000 array measurements. Comparisons of the average platform position with the expected position indicated absolute deviations of  90% when criteria of 0.5%/0.5 mm were used. Results using this novel phantom arrangement indicate that the RPM system is capable of accurately gating x-ray exposure during the delivery of a fixed-field treatment beam.

  3. Time-resolved dosimetric verification of respiratory-gated radiotherapy exposures using a high-resolution 2D ionisation chamber array

    Science.gov (United States)

    King, R. B.; Agnew, C. E.; O'Connell, B. F.; Prise, K. M.; Hounsell, A. R.; McGarry, C. K.

    2016-08-01

    The aim of this work was to track and verify the delivery of respiratory-gated irradiations, performed with three versions of TrueBeam linac, using a novel phantom arrangement that combined the OCTAVIUS® SRS 1000 array with a moving platform. The platform was programmed to generate sinusoidal motion of the array. This motion was tracked using the real-time position management (RPM) system and four amplitude gating options were employed to interrupt MV beam delivery when the platform was not located within set limits. Time-resolved spatial information extracted from analysis of x-ray fluences measured by the array was compared to the programmed motion of the platform and to the trace recorded by the RPM system during the delivery of the x-ray field. Temporal data recorded by the phantom and the RPM system were validated against trajectory log files, recorded by the linac during the irradiation, as well as oscilloscope waveforms recorded from the linac target signal. Gamma analysis was employed to compare time-integrated 2D x-ray dose fluences with theoretical fluences derived from the probability density function for each of the gating settings applied, where gamma criteria of 2%/2 mm, 1%/1 mm and 0.5%/0.5 mm were used to evaluate the limitations of the RPM system. Excellent agreement was observed in the analysis of spatial information extracted from the SRS 1000 array measurements. Comparisons of the average platform position with the expected position indicated absolute deviations of  90% when criteria of 0.5%/0.5 mm were used. Results using this novel phantom arrangement indicate that the RPM system is capable of accurately gating x-ray exposure during the delivery of a fixed-field treatment beam.

  4. Features of Formation of Ohmic Contacts and Gate on Epitaxial Heterostructure of AlGaN / GaN High Electron Mobility Transistor

    Directory of Open Access Journals (Sweden)

    I.A. Rogachev

    2016-06-01

    Full Text Available Reported about study of processes of formation of Ti / Al / Ni / Au ohmic contacts to heterostructures AlGaN / GaN and gate Ni / Au. Investigated of process recess the semiconductor layer for minimum resistance of ohmic contact – 0.4 Ohm·mm. Studied influence of encapsulation ohmic contacts on their surface morphology.

  5. Self-Aligned ALD AlOx T-gate Insulator for Gate Leakage Current Suppression in SiNx-Passivated AlGaN/GaN HEMTs

    Science.gov (United States)

    2010-01-01

    Self-aligned ALD AlOx T-gate insulator for gate leakage current suppression in SiNx-passivated AlGaN/ GaN HEMTs David J. Meyer *, Robert Bass, D...concept metal–insulator–semiconductor (MIS) AlGaN/ GaN high-electron mobility transistor ( HEMT ) that uses a self-aligned 10 nm AlOx gate insulator and...Au gate metal layers to fabri- cate submicron insulated T-gates for AlGaN/ GaN high-electron mobility transistors ( HEMTs ). Metal–insulator

  6. MR-guided percutaneous biopsy of solitary pulmonary lesions using a 1.0-T open high-field MRI scanner with respiratory gating

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ming; Huang, Jie; Xu, Yujun; He, Xiangmeng; Lue, Yubo; Liu, Qiang; Li, Chengli [Department of Interventional MRI, Shandong Medical Imaging Research Institute affiliated to Shandong University, Shandong Key Laboratory of Advanced Medical Imaging Technologies and Applications, Jinan, Shandong (China); Li, Lei [Qingdao Central Hospital, Department of Interventional Radiology, Qingdao, Shandong (China); Blanco Sequeiros, Roberto [Turku University Hospital, The South Western Finland Imaging Centre, Turku (Finland)

    2017-04-15

    To prospectively evaluate the feasibility, safety and accuracy of MR-guided percutaneous biopsy of solitary pulmonary lesions using a 1.0-T open MR scanner with respiratory gating. Sixty-five patients with 65 solitary pulmonary lesions underwent MR-guided percutaneous coaxial cutting needle biopsy using a 1.0-T open MR scanner with respiratory gating. Lesions were divided into two groups according to maximum lesion diameters: ≤2.0 cm (n = 31) and >2.0 cm (n = 34). The final diagnosis was established in surgery and subsequent histology. Diagnostic accuracy, sensitivity and specificity were compared between the groups using Fisher's exact test. Accuracy, sensitivity and specificity of MRI-guided percutaneous pulmonary biopsy in diagnosing malignancy were 96.9 %, 96.4 % and 100 %, respectively. Accuracy, sensitivity and specificity were 96.8 %, 96.3 % and 100 % for lesions 2.0 cm or smaller and 97.1 %, 96.4 % and 100 %, respectively, for lesions larger than 2.0 cm. There was no significant difference between the two groups (P > 0.05). Biopsy-induced complications encountered were pneumothorax in 12.3 % (8/65) and haemoptysis in 4.6 % (3/65). There were no serious complications. MRI-guided percutaneous biopsy using a 1.0-T open MR scanner with respiratory gating is an accurate and safe diagnostic technique in evaluation of pulmonary lesions. (orig.)

  7. Effect of gate dielectrics on the performance of p-type Cu2O TFTs processed at room temperature

    KAUST Repository

    Al-Jawhari, Hala A.

    2013-12-01

    Single-phase Cu2O films with p-type semiconducting properties were successfully deposited by reactive DC magnetron sputtering at room temperature followed by post annealing process at 200°C. Subsequently, such films were used to fabricate bottom gate p-channel Cu2O thin film transistors (TFTs). The effect of using high-κ SrTiO3 (STO) as a gate dielectric on the Cu2O TFT performance was investigated. The results were then compared to our baseline process which uses a 220 nm aluminum titanium oxide (ATO) dielectric deposited on a glass substrate coated with a 200 nm indium tin oxide (ITO) gate electrode. We found that with a 150 nm thick STO, the Cu2O TFTs exhibited a p-type behavior with a field-effect mobility of 0.54 cm2.V-1.s-1, an on/off ratio of around 44, threshold voltage equaling -0.62 V and a sub threshold swing of 1.64 V/dec. These values were obtained at a low operating voltage of -2V. The advantages of using STO as a gate dielectric relative to ATO are discussed. © (2014) Trans Tech Publications, Switzerland.

  8. Hanford Site technical baseline database

    Energy Technology Data Exchange (ETDEWEB)

    Porter, P.E.

    1996-09-30

    This document includes a cassette tape that contains the Hanford specific files that make up the Hanford Site Technical Baseline Database as of September 30, 1996. The cassette tape also includes the delta files that dellinate the differences between this revision and revision 4 (May 10, 1996) of the Hanford Site Technical Baseline Database.

  9. Hanford Site technical baseline database

    Energy Technology Data Exchange (ETDEWEB)

    Porter, P.E., Westinghouse Hanford

    1996-05-10

    This document includes a cassette tape that contains the Hanford specific files that make up the Hanford Site Technical Baseline Database as of May 10, 1996. The cassette tape also includes the delta files that delineate the differences between this revision and revision 3 (April 10, 1996) of the Hanford Site Technical Baseline Database.

  10. Plutonium Immobilization Project Baseline Formulation

    Energy Technology Data Exchange (ETDEWEB)

    Ebbinghaus, B.

    1999-02-01

    A key milestone for the Immobilization Project (AOP Milestone 3.2a) in Fiscal Year 1998 (FY98) is the definition of the baseline composition or formulation for the plutonium ceramic form. The baseline formulation for the plutonium ceramic product must be finalized before the repository- and plant-related process specifications can be determined. The baseline formulation that is currently specified is given in Table 1.1. In addition to the baseline formulation specification, this report provides specifications for two alternative formulations, related compositional specifications (e.g., precursor compositions and mixing recipes), and other preliminary form and process specifications that are linked to the baseline formulation. The preliminary specifications, when finalized, are not expected to vary tremendously from the preliminary values given.

  11. BMC{trademark}: Baseline report; Greenbook (chapter)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-31

    Barrier Membrane Containment (BMC){trademark} is a high-density polyethylene membrane (HDPE) groundwater barrier and pass-through system, with applications ranging from plume control and containment to groundwater manipulation coupled with in-site treatment. BMC{trademark} system can function as a permeable or impermeable reaction wall, a cut-off wall, interceptor trenches, a barrier with collection and/or monitoring system, and a pass-through in a funnel and gate configuration. BMC{trademark} can be inspected with a down-hole video camera, producing a permanent VHS format tape, insuring the integrity of the wall and the interlocking joints.

  12. Optimizing link efficiency for gated DPCCH transmission on HSUPA

    DEFF Research Database (Denmark)

    Zarco, Carlos Ruben Delgado; Wigard, Jeroen; Kolding, T. E.

    2007-01-01

    To minimize the terminal's transmission power in bursty uplink traffic conditions, the evolved High-Speed Uplink Packet Access (HSUPA) concept in 3GPP WCDMA includes a feature known as Dedicated Physical Control Channel (DPCCH) gating. We present here a detailed link level study of gating from...... a link efficiency (LE) perspective; LE being expressed in bits per second per Watt. While the overall gain mechanisms of gating are well known, we show how special challenges related to discontinuous Enhanced Dedicated Channel (E-DCH) transmission can be addressed for high link and system performance. We...... consider the E-DCH performance degradation caused by gating on other radio procedures relying on the DPCCH, such as inner and outer loop power control. Our studies show that gating is beneficial for both for 2 and 10 ms transmission time intervals. The gains in terms of LE with a Vehicular A 30 kmph...

  13. A quantum Fredkin gate.

    Science.gov (United States)

    Patel, Raj B; Ho, Joseph; Ferreyrol, Franck; Ralph, Timothy C; Pryde, Geoff J

    2016-03-01

    Minimizing the resources required to build logic gates into useful processing circuits is key to realizing quantum computers. Although the salient features of a quantum computer have been shown in proof-of-principle experiments, difficulties in scaling quantum systems have made more complex operations intractable. This is exemplified in the classical Fredkin (controlled-SWAP) gate for which, despite theoretical proposals, no quantum analog has been realized. By adding control to the SWAP unitary, we use photonic qubit logic to demonstrate the first quantum Fredkin gate, which promises many applications in quantum information and measurement. We implement example algorithms and generate the highest-fidelity three-photon Greenberger-Horne-Zeilinger states to date. The technique we use allows one to add a control operation to a black-box unitary, something that is impossible in the standard circuit model. Our experiment represents the first use of this technique to control a two-qubit operation and paves the way for larger controlled circuits to be realized efficiently.

  14. Experimental analysis of flow of ductile cast iron in stream lined gating systems

    DEFF Research Database (Denmark)

    Skov-Hansen, Søren; Green, Nick; Tiedje, Niels Skat

    2008-01-01

    Streamlined gating systems have been developed for production of high integrity ductile cast iron parts. Flow of ductile cast iron in streamlined gating systems was studied in glass fronted sand moulds where flow in the gating system and casting was recorded by a digital video camera. These resul...

  15. Plasmonic response of partially gated field effect transistors

    Science.gov (United States)

    Rudin, S.; Rupper, G.; Reed, M. L.; Shur, M.

    2016-09-01

    Electron density oscillations in the transistor channels - plasma waves in the two-dimensional electron gas - determine the high frequency device response. Plasmonic field effect transistors have emerged as very sensitive, tunable, and extremely fast detectors of THz radiation. They have been implemented using silicon (CMOS), AlGaAs/InGaAs HEMTs, and AlGaAs/InGaAs HEMTs, with the HEMTs shown to operate more efficiently at higher THz frequencies. These HEMTs have both gated and ungated sections of the device channel between the source and drain, and the photovoltaic regime of operation requires an asymmetric gate placement in the device channel. The interactions of the plasma waves in the gated and ungated channel regions strongly affect the overall response and have been investigated in numerous publications. This work addresses a new aspect of such interaction - the effect of the relative position of the gated and ungated section. We show this previously unexplored effect plays a dominant role in determining the response. The results of the numerical simulation based on the solution of the complete system of the hydrodynamic equations describing the electron fluid in the device channel show that the inverse response frequency could be approximated by the sum of the gated plasmon transit time in the gated section of the device, the ungated plasmon transit time in the ungated section of the device between the gate and the drain, and the RC gate-to-source constant. Here R and C are the resistance and capacitance of the gate to source section. Hence, the highest speed is achieved when the gate is as close to the source as possible. This suggests a novel plasmonic detector design, where the gate and source electrode overlap, which is shown to have a superior frequency response for the same distance between the source and the drain.

  16. Oscillation Baselining and Analysis Tool

    Energy Technology Data Exchange (ETDEWEB)

    2017-03-27

    PNNL developed a new tool for oscillation analysis and baselining. This tool has been developed under a new DOE Grid Modernization Laboratory Consortium (GMLC) Project (GM0072 - “Suite of open-source applications and models for advanced synchrophasor analysis”) and it is based on the open platform for PMU analysis. The Oscillation Baselining and Analysis Tool (OBAT) performs the oscillation analysis and identifies modes of oscillations (frequency, damping, energy, and shape). The tool also does oscillation event baselining (fining correlation between oscillations characteristics and system operating conditions).

  17. Effect of Gate Length on the DC and RF Performance of GaN HEMT Devices

    Directory of Open Access Journals (Sweden)

    Ahmet Toprak

    2015-09-01

    Full Text Available In this work, we report GaN high-electron-mobility-transistors (HEMTs on SiC with gate lengths of various dimensions for optimum performance. 125 µm gate width, 4 µm drain source spacing AlGaN/GaN HEMTs with gate lengths of 0.3, 0.6, 0.8, and 1.0 µm were fabricated. For devices with the gate lengths in the range of 0.3-0.8 µm, with an increase in gate length, the output power density (Pout at 4 GHz is increased from 1W/mm to 1.5W/mm, although the Ids,max, gm, ft and fmax values are decreased in acceptable limits. The great enhancement in Pout with the increase in the gate length is due to fact that the increase in gate length affects the controllability of the electric field under the channel; hence the peak value of the electric field under gate contact decreases and the electric field variation under the gate contacts is smoother. For the device with the gate length of 1.0 µm Ids,max , gm values are almost the same as the values with the gate length of 0.8 µm, but Pout is decreased, since with this gate length the increase in parasitic capacitances is more effective and this limits the improvement due to the gate length increase.

  18. MR-guided percutaneous biopsy of solitary pulmonary lesions using a 1.0-T open high-field MRI scanner with respiratory gating.

    Science.gov (United States)

    Liu, Ming; Huang, Jie; Xu, Yujun; He, Xiangmeng; Li, Lei; Lü, Yubo; Liu, Qiang; Sequeiros, Roberto Blanco; Li, Chengli

    2017-04-01

    To prospectively evaluate the feasibility, safety and accuracy of MR-guided percutaneous biopsy of solitary pulmonary lesions using a 1.0-T open MR scanner with respiratory gating. Sixty-five patients with 65 solitary pulmonary lesions underwent MR-guided percutaneous coaxial cutting needle biopsy using a 1.0-T open MR scanner with respiratory gating. Lesions were divided into two groups according to maximum lesion diameters: ≤2.0 cm (n = 31) and >2.0 cm (n = 34). The final diagnosis was established in surgery and subsequent histology. Diagnostic accuracy, sensitivity and specificity were compared between the groups using Fisher's exact test. Accuracy, sensitivity and specificity of MRI-guided percutaneous pulmonary biopsy in diagnosing malignancy were 96.9 %, 96.4 % and 100 %, respectively. Accuracy, sensitivity and specificity were 96.8 %, 96.3 % and 100 % for lesions 2.0 cm or smaller and 97.1 %, 96.4 % and 100 %, respectively, for lesions larger than 2.0 cm. There was no significant difference between the two groups (P > 0.05). Biopsy-induced complications encountered were pneumothorax in 12.3 % (8/65) and haemoptysis in 4.6 % (3/65). There were no serious complications. MRI-guided percutaneous biopsy using a 1.0-T open MR scanner with respiratory gating is an accurate and safe diagnostic technique in evaluation of pulmonary lesions. • MRI-guided percutaneous lung biopsy using a 1.0-T open MR scanner is feasibility. • 96.9 % differentiation accuracy of malignant and benign lung lesions is possible. • No serious complications occurred in MRI-guided lung biopsy.

  19. [An autopsy case of amyotrophic lateral sclerosis with prominent muscle cramps, fasciculation, and high titer of anti-voltage gated potassium channel (VGKC) complex antibody].

    Science.gov (United States)

    Sato, Aki; Sakai, Naoko; Shinbo, Junsuke; Hashidate, Hideki; Igarashi, Shuichi; Kakita, Akiyoshi; Yamazaki, Motoyoshi

    2014-01-01

    The patient was a 55-year-old male who had prominent fasciculation and muscle cramps. Muscle weakness and atrophy of the trunk, respiratory system, and extremities gradually progressed. On the basis of these features, we diagnosed this patient as having amyotrophic lateral sclerosis (ALS), however, the upper motor neuron signs were not significant. Following the detection of the anti-voltage gated potassium channel (VGKC) complex antibody at 907.5 pM (normal VGKC complex antibody in the development of cramp-fasciculation syndrome has been speculated. In this ALS patient, the antibodies might be associated with pathomechanisms underlying the characteristic symptoms.

  20. High power terahertz emission from a single gate AlGaN/GaN field effect transistor with periodic Ohmic contacts for plasmon coupling

    Science.gov (United States)

    Onishi, Toshikazu; Tanigawa, Tatsuya; Takigawa, Shinichi

    2010-08-01

    We report on room temperature terahertz (THz) emission by a single, short gate AlGaN/GaN field effect transistor with grating Ohmic contacts. The fingers of metal contacts are fabricated at the nanoscale in length and spacing in order to work as a radiation coupler of electron plasmons in the THz range. Spectrum analysis revealed a broadband emission centered at 1.5 THz with a controlled polarization by the grating contacts. The measured output power is linearly increased with the drain input power and reached up to 1.8 μW.

  1. Impact of gate geometry on ionic liquid gated ionotronic systems

    Science.gov (United States)

    Wong, A. T.; Noh, J. H.; Pudasaini, P. R.; Wolf, B.; Balke, N.; Herklotz, A.; Sharma, Y.; Haglund, A. V.; Dai, S.; Mandrus, D.; Rack, P. D.; Ward, T. Z.

    2017-04-01

    Ionic liquid electrolytes are gaining widespread application as a gate dielectric used to control ion transport in functional materials. This letter systematically examines the important influence that device geometry in standard "side gate" 3-terminal geometries plays in device performance of a well-known oxygen ion conductor. We show that the most influential component of device design is the ratio between the area of the gate electrode and the active channel, while the spacing between these components and their individual shapes has a negligible contribution. These findings provide much needed guidance in device design intended for ionotronic gating with ionic liquids.

  2. Materials Fundamentals of Gate Dielectrics

    CERN Document Server

    Demkov, Alexander A

    2006-01-01

    This book presents materials fundamentals of novel gate dielectrics that are being introduced into semiconductor manufacturing to ensure the continuous scalling of the CMOS devices. This is a very fast evolving field of research so we choose to focus on the basic understanding of the structure, thermodunamics, and electronic properties of these materials that determine their performance in device applications. Most of these materials are transition metal oxides. Ironically, the d-orbitals responsible for the high dielectric constant cause sever integration difficulties thus intrinsically limiting high-k dielectrics. Though new in the electronics industry many of these materials are wel known in the field of ceramics, and we describe this unique connection. The complexity of the structure-property relations in TM oxides makes the use of the state of the art first-principles calculations necessary. Several chapters give a detailed description of the modern theory of polarization, and heterojunction band discont...

  3. Quivira NWR biological baseline data

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This dataset is biological baseline data for Quivira National Wildlife Refuge as of January 2016. It contains data on species found on the refuge, when and where...

  4. 324 Building Baseline Radiological Characterization

    Energy Technology Data Exchange (ETDEWEB)

    R.J. Reeder, J.C. Cooper

    2010-06-24

    This report documents the analysis of radiological data collected as part of the characterization study performed in 1998. The study was performed to create a baseline of the radiological conditions in the 324 Building.

  5. Physical and electrical characteristics of AlGaN/GaN metal-oxide-semiconductor high-electron-mobility transistors with rare earth Er{sub 2}O{sub 3} as a gate dielectric

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Ray-Ming, E-mail: rmlin@mail.cgu.edu.tw; Chu, Fu-Chuan; Das, Atanu; Liao, Sheng-Yu; Chou, Shu-Tsun; Chang, Liann-Be

    2013-10-01

    In this study, the rare earth erbium oxide (Er{sub 2}O{sub 3}) was deposited using an electron beam onto an AlGaN/GaN heterostructure to fabricate metal-oxide-semiconductor high-electron-mobility transistors (MOS–HEMTs) that exhibited device performance superior to that of a conventional HEMT. Under similar bias conditions, the gate leakage currents of these MOS–HEMT devices were four orders of magnitude lower than those of conventional Schottky gate HEMTs. The measured sub-threshold swing (SS) and the effective trap state density (N{sub t}) of the MOS–HEMT were 125 mV/decade and 4.3 × 10{sup 12} cm{sup −2}, respectively. The dielectric constant of the Er{sub 2}O{sub 3} layer in this study was 14, as determined through capacitance–voltage measurements. In addition, the gate–source reverse breakdown voltage increased from –166 V for the conventional HEMT to –196 V for the Er{sub 2}O{sub 3} MOS–HEMT. - Highlights: ► GaN/AlGaN/Er{sub 2}O{sub 3} metal-oxide semiconductor high electron mobility transistor ► Physical and electrical characteristics are presented. ► Electron beam evaporated Er{sub 2}O{sub 3} with excellent surface roughness ► Device exhibits reduced gate leakage current and improved I{sub ON}/I{sub OFF} ratio.

  6. High-resolution imaging of pulmonary ventilation and perfusion with {sup 68}Ga-VQ respiratory gated (4-D) PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Callahan, Jason [Centre for Molecular Imaging, Peter MacCallum Cancer Centre, East Melbourne, VIC (Australia); Hofman, Michael S. [The University of Melbourne, Department of Medicine, Peter MacCallum Cancer Centre, Centre for Molecular Imaging, East Melbourne, VIC (Australia); Siva, Shankar [The University of Melbourne, Peter MacCallum Cancer Centre, Department of Radiation Oncology, East Melbourne, VIC (Australia); The University of Melbourne, Sir Peter MacCallum Department of Oncology, East Melbourne, VIC (Australia); Kron, Tomas [The University of Melbourne, Sir Peter MacCallum Department of Oncology, East Melbourne, VIC (Australia); The University of Melbourne, Peter MacCallum Cancer Centre, Department of Physical Sciences, East Melbourne, VIC (Australia); Schneider, Michal E. [Monash University, Department of Medical Imaging and Radiation Science, Clayton, VIC (Australia); Binns, David; Eu, Peter [Peter MacCallum Cancer Centre, Centre for Cancer Imaging, East Melbourne, VIC (Australia); Hicks, Rodney J. [The University of Melbourne, Sir Peter MacCallum Department of Oncology, Peter MacCallum Cancer Centre, Centre for Molecular Imaging, East Melbourne, VIC (Australia)

    2014-02-15

    Our group has previously reported on the use of {sup 68}Ga-ventilation/perfusion (VQ) PET/CT scanning for the diagnosis of pulmonary embolism. We describe here the acquisition methodology for {sup 68}Ga-VQ respiratory gated (4-D) PET/CT and the effects of respiratory motion on image coregistration in VQ scanning. A prospective study was performed in 15 patients with non-small-cell lung cancer. 4-D PET and 4-D CT images were acquired using an infrared marker on the patient's abdomen as a surrogate for breathing motion following inhalation of Galligas and intravenous administration of {sup 68}Ga-macroaggregated albumin. Images were reconstructed with phase-matched attenuation correction. The lungs were contoured on CT and PET VQ images during free-breathing (FB) and at maximum inspiration (Insp) and expiration (Exp). The similarity between PET and CT volumes was measured using the Dice coefficient (DC) comparing the following groups; (1) FB-PET/CT, (2) InspPET/InspCT, (3) ExpPET/Exp CT, and (4) FB-PET/AveCT. A repeated measures one-way ANOVA with multiple comparison Tukey tests were performed to evaluate any difference between the groups. Diaphragmatic motion in the superior-inferior direction on the 4-D CT scan was also measured. 4-D VQ scanning was successful in all patients without additional acquisition time compared to the nongated technique. The highest volume overlap was between ExpPET and ExpCT and between FB-PET and AveCT with a DC of 0.82 and 0.80 for ventilation and perfusion, respectively. This was significantly better than the DC comparing the other groups (0.78-0.79, p < 0.05). These values agreed with a visual inspection of the images with improved image coregistration around the lung bases. The diaphragmatic motion during the 4-D CT scan was highly variable with a range of 0.4-3.4 cm (SD 0.81 cm) in the right lung and 0-2.8 cm (SD 0.83 cm) in the left lung. Right-sided diaphragmatic nerve palsy was observed in 3 of 15 patients. {sup 68}Ga-VQ 4-D

  7. Exploration of somatosensory P50 gating in schizophrenia spectrum patients

    DEFF Research Database (Denmark)

    Arnfred, Sidse M.; Chen, Andrew C. N.

    2004-01-01

    Originally, the hypothesis of a sensory gating defect in schizophrenia evolved from studies of somatosensory evoked potentials (SEP), although the idea has primarily been pursued in the auditory modality. Gating is the relative attenuation of amplitude following the second stimulus in a stimulus...... pair. Recently, SEP P50 gating was seen when recording the SEP P50 in a paradigm similar to the one used for auditory P50 gating. Hypothetically, abnormality of somatosensory information processing could be related to anhedonia, which is considered a core feature of schizophrenia. Twelve unmedicated......, but no gating defect. The reduced amplitude was particularly evident in subjects with high scores on the Revised Social Anhedonia Scale. Early somatosensory information processing seems abnormal in schizophrenia spectrum patients. This could be in agreement with the theory of loss of the benefit of regularity...

  8. Biofouling surveillance at a power station with seawater intake gates

    Energy Technology Data Exchange (ETDEWEB)

    Sasikumar, N.; Nair, K.V.K. [Indira Gandhi Centre for Atomic Research, Kalpakkam (India)

    1997-04-01

    Biofouling monitoring of the seawater intake gates of Madras` atomic power station (MAPS) in India was carried out for a period of two years. The settlement and growth rates, composition, and biomass of fouling between the intake filter gates and the test panels exposed in the coastal waters were compared and the results showed significant differences. The major foulant of the tunnel -green mussel, Perna viridis, and barnacle, Megabalanus tintinnabulum - though generally absent on test panels, was present on the intake gates. Relatively-high growth rates with heavy biomass were found at the intake gates as compared to the test panel. The study suggests that the intake gates can be used for a reliable fouling prediction in coastal power plants. (Author).

  9. On modeling the digital gate delay under process variation

    Institute of Scientific and Technical Information of China (English)

    Gao Mingzhi; Ye Zuochang; Wang Yan; Yu Zhiping

    2011-01-01

    To achieve a characterization method for the gate delay library used in block based statistical static timing analysis with neither unacceptably poor accuracy nor forbiddingly high cost,we found that general-purpose gate delay models are useful as intermediaries between the circuit simulation data and the gate delay models in required forms.In this work,two gate delay models for process variation considering different driving and loading conditions are proposed.From the testing results,these two models,especially the one that combines effective dimension reduction (EDR) from statistics society with comprehensive gate delay models,offer good accuracy with low characterization cost,and they are thus competent for use in statistical timing analysis (SSTA).In addition,these two models have their own value in other SSTA techniques.

  10. Potential demographic and baselines variables for risk stratification of high-risk post-myocardial infarction patients in the era of implantable cardioverter-defibrillator - a prognostic indicator

    DEFF Research Database (Denmark)

    Yap, Yee Guan; Duong, Trinh; Bland, Martin

    2008-01-01

    , sex, previous MI or angina, hypertension, diabetes, systolic blood pressure, heart rate, NYHA functional class and non-Q wave infarct on electrocardiogram. Distinct survival curves were obtained for 3 risk groups based on the median and inter-quartile range for the prognostic index. In the high-risk......BACKGROUND: Risk stratification after myocardial infarction (MI) remains expensive and disappointing. We designed a prognostic indicator using demographic information to select patients at risk of dying after MI. METHOD AND RESULTS: We combined individual patient data from the placebo arms of EMIAT......, CAMIAT, TRACE and DIAMOND-MI with LVEF 10 ventricular premature beats/hour or a run of ventricular tachycardia). Risk factors for mortality beginning at day 45 post-MI up to 2 years were examined using Cox regression analysis. Risk scores were derived from the equation of a Cox regression model...

  11. Gate complexity using Dynamic Programming

    OpenAIRE

    Sridharan, Srinivas; Gu, Mile; James, Matthew R.

    2008-01-01

    The relationship between efficient quantum gate synthesis and control theory has been a topic of interest in the quantum control literature. Motivated by this work, we describe in the present article how the dynamic programming technique from optimal control may be used for the optimal synthesis of quantum circuits. We demonstrate simulation results on an example system on SU(2), to obtain plots related to the gate complexity and sample paths for different logic gates.

  12. Localizing a gate in CFTR

    OpenAIRE

    Gao, Xiaolong; Hwang, Tzyh-Chang

    2015-01-01

    Cystic fibrosis transmembrane conductance regulator (CFTR), albeit a bona fide member of the ATP-binding cassette (ABC) transporter superfamily, is an ATP-gated chloride channel. However, phylogenetic analysis has led to a popular conjecture that CFTR evolves from a primordial ABC exporter by simply degenerating the cytoplasmic gate. This degraded transporter hypothesis predicts that CFTR’s gate is located at the external end of the substrate translocation pathway as the one documented in the...

  13. High-performance low-leakage regions of nano-scaled CMOS digital gates under variations of threshold voltage and mobility

    Institute of Scientific and Technical Information of China (English)

    Hossein AGHABABA; Behjat FOROUZANDEH; Ali AFZALI-KUSHA

    2012-01-01

    We propose a modeling methodology for both leakage power consumption and delay of basic CMOS digital gates in the presence of threshold voltage and mobility variations.The key parameters in determining the leakage and delay are OFF and ON currents,respectively,which are both affected by the variation of the threshold voltage.Additionally,the current is a strong function of mobility.The proposed methodology relies on a proper modeling of the threshold voltage and mobility variations,which may be induced by any source.Using this model,in the plane of threshold voltage and mobility,we determine regions for different combinations of performance (speed) and leakage.Based on these regions,we discuss the trade-offbetween leakage and delay where the leakage-delay-product is the optimization objective.To assess the accuracy of the proposed model,we compare its predictions with those of HSPICE simulations for both basic digital gates and ISCAS85 benchmark circuits in 45-,65-,and 90-nm technologies.

  14. In situ atomic layer nitridation on the top and down regions of the amorphous and crystalline high-K gate dielectrics

    Science.gov (United States)

    Tsai, Meng-Chen; Lee, Min-Hung; Kuo, Chin-Lung; Lin, Hsin-Chih; Chen, Miin-Jang

    2016-11-01

    Amorphous and crystalline ZrO2 gate dielectrics treated with in situ atomic layer nitridation on the top and down regions (top and down nitridation, abbreviated as TN and DN) were investigated. In a comparison between the as-deposited amorphous DN and TN samples, the DN sample has a lower leakage current density (Jg) of ∼7 × 10-4 A/cm2 with a similar capacitance equivalent thickness (CET) of ∼1.53 nm, attributed to the formation of SiOxNy in the interfacial layer (IL). The post-metallization annealing (PMA) leads to the transformation of ZrO2 from the amorphous to the crystalline tetragonal/cubic phase, resulting in an increment of the dielectric constant. The PMA-treated TN sample exhibits a lower CET of 1.22 nm along with a similar Jg of ∼1.4 × 10-5 A/cm2 as compared with the PMA-treated DN sample, which can be ascribed to the suppression of IL regrowth. The result reveals that the nitrogen engineering in the top and down regions has a significant impact on the electrical characteristics of amorphous and crystalline ZrO2 gate dielectrics, and the nitrogen incorporation at the top of crystalline ZrO2 is an effective approach to scale the CET and Jg, as well as to improve the reliability.

  15. GATE TYPE SELECTION BASED ON FUZZY MAPPING

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Gate type selection is very important for mould design. Improper gate type may lead to poor product quality and low production efficiency. Although numerical simulation approach could be used to optimize gate location, the determination of gate type is still up to designers' experience. A novel method for selecting gate type based on fuzzy logic is proposed. The proposed methodology follows three steps:Design requirements for gate is extracted and generalized; Possible gate types (design schemes) are presented; The fuzzy mapping relationship between gate design requirements and gate design scheme is established based on fuzzy composition and fuzzy relation transition matrices that are assigned by domain experts.

  16. The baseline characteristics and interim analyses of the high-risk sentinel cohort of the Vietnam Initiative on Zoonotic InfectiONS (VIZIONS).

    Science.gov (United States)

    Carrique-Mas, Juan J; Tue, Ngo T; Bryant, Juliet E; Saylors, Karen; Cuong, Nguyen V; Hoa, Ngo T; An, Nguyen N; Hien, Vo B; Lao, Pham V; Tu, Nguyen C; Chuyen, Nguyen K; Chuc, Nguyen T K; Tan, Dinh V; Duong, Hoang Van V; Toan, Tran K; Chi, Nguyen T Y; Campbell, James; Rabaa, Maia A; Nadjm, Behzad; Woolhouse, Mark; Wertheim, Heiman; Thwaites, Guy; Baker, Stephen

    2015-12-10

    The Vietnam Initiative for Zoonotic Infections (VIZIONS) includes community-based 'high-risk sentinel cohort' (HRSC) studies investigating individuals at risk of zoonotic infection due to occupational or residential exposure to animals. A total of 852 HRSC members were recruited between March 2013 and August 2014 from three provinces (Ha Noi, Dak Lak, and Dong Thap). The most numerous group (72.8%) corresponded to individuals living on farms, followed by slaughterers (16.3%) and animal health workers (8.5%). Nasal/pharyngeal and rectal swabs were collected from HRSC members at recruitment and after notifying illness. Exposure to exotic animals (including wild pigs, porcupine, monkey, civet, bamboo rat and bat) was highest for the Dak Lak cohort (53.7%), followed by Ha Noi (13.7%) and Dong Thap (4.0%). A total of 26.8% of individuals reported consumption of raw blood over the previous year; 33.6% slaughterers reported no use of protective equipment at work. Over 686 person-years of observation, 213 episodes of suspect infectious disease were notified, equivalent of 0.35 reports per person-year. Responsive samples were collected from animals in the farm cohort. There was noticeable time and space clustering of disease episodes suggesting that the VIZIONS set up is also suitable for the formal epidemiological investigation of disease outbreaks.

  17. Normal mode gating motions of a ligand-gated ion channel persist in a fully hydrated lipid bilayer model.

    Science.gov (United States)

    Bertaccini, Edward J; Trudell, James R; Lindahl, Erik

    2010-08-18

    We have previously used molecular modeling and normal-mode analyses combined with experimental data to visualize a plausible model of a transmembrane ligand-gated ion channel. We also postulated how the gating motion of the channel may be affected by the presence of various ligands, especially anesthetics. As is typical for normal-mode analyses, those studies were performed in vacuo to reduce the computational complexity of the problem. While such calculations constitute an efficient way to model the large scale structural flexibility of transmembrane proteins, they can be criticized for neglecting the effects of an explicit phospholipid bilayer or hydrated environment. Here, we show the successful calculation of normal-mode motions for our model of a glycine α-1 receptor, now suspended in a fully hydrated lipid bilayer. Despite the almost uniform atomic density, the introduction of water and lipid does not grossly distort the overall gating motion. Normal-mode analysis revealed that even a fully immersed glycine α-1 receptor continues to demonstrate an iris-like channel gating motion as a low-frequency, high-amplitude natural harmonic vibration consistent with channel gating. Furthermore, the introduction of periodic boundary conditions allows the examination of simultaneous harmonic vibrations of lipid in synchrony with the protein gating motions that are compatible with reasonable lipid bilayer perturbations. While these perturbations tend to influence the overall protein motion, this work provides continued support for the iris-like motion model that characterizes gating within the family of ligand-gated ion channels.

  18. Flexural-Phonon Scattering Induced by Electrostatic Gating in Graphene

    DEFF Research Database (Denmark)

    Gunst, Tue; Kaasbjerg, Kristen; Brandbyge, Mads

    2017-01-01

    Graphene has an extremely high carrier mobility partly due to its planar mirror symmetry inhibiting scattering by the highly occupied acoustic flexural phonons. Electrostatic gating of a graphene device can break the planar mirror symmetry, yielding a coupling mechanism to the flexural phonons.......We examine the effect of the gate-induced one-phonon scattering on the mobility for several gate geometries and dielectric environments using first-principles calculations based on density functional theory and the Boltzmann equation. We demonstrate that this scattering mechanism can be a mobility...

  19. High K capacitors and OFET gate dielectrics from self-assembled BaTiO{sub 3} and (Ba,Sr)TiO{sub 3} nanocrystals in the superparaelectric limit

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Limin; O' Brien, Stephen [Department of Chemistry, City University of New York, City College of New York 1131 Marshak Building, New York, NY 10031 (United States); Jia, Zhang; Kymissis, Ioannis [Department of Electrical Engineering, Columbia University New York, NY (United States)

    2010-02-22

    Nanodielectrics is an emerging field with applications in capacitors, gate dielectrics, energy storage, alternatives to Li-ion batteries, and frequency modulation in communications devices. Self-assembly of high k dielectric nanoparticles is a highly attractive means to produce nanostructured films with improved performance - namely dielectric tunability, low leakage, and low loss - as a function of size, composition, and structure. One of the major challenges is conversion of the nanoparticle building block into a reliable thin film device at conditions consistent with integrated device manufacturing or plastic electronics. Here, the development of BaTiO{sub 3} and (Ba,Sr)TiO{sub 3} superparaelectric uniform nanocrystal (8-12 nm) films prepared at room temperature by evaporative driven assembly with no annealing step is reported. Thin film inorganic and polymer composite capacitors show dielectric constants in the tunable range of 10-30, dependent on composition, and are confirmed to be superparaelectric. Organic thin film transistor (TFT) devices on flexible substrates demonstrate the readiness of nanoparticle-assembled films as gate dielectrics in device fabrication. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  20. Ligustrazine inhibits high voltage-gated Ca2+ and TTX-resistant Na+ channels of primary sensory neuron and thermal nociception in the rat:a study on peripheral mechanism

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective Ligustrazine, also named as tetramethylpyrazine, is a compound purified from Ligusticum chuanxiong hort and has ever been testified to be a calcium antagonist. The present investigation was to determine the antinociceptive effect of ligustrazine and, if any, the peripheral ionic mechanism involved. Methods Paw withdrawal Latency(PWL) to noxious heating was measured in vivo and whole-cell patch recording was performed on small dorsal root ganglion (DRG) neurons. Results Intraplantar injection of ligustrazine (0.5 mg in 25 μl) significantly prolonged the withdrawal latency of ipsilateral hindpaw to noxious heating in the rat. Ligustrazine not only reversibly inhibited high-voltage gated calcium current of dorsal root ganglion (DRG) neuron in dose-dependent manner with IC50 of 1.89 mmol/L, but also decreased tetrodotoxin (TTX) -resistant sodium current in relatively selective and dose-dependent manner with IC50 of2.49 mmol/L. Conclusion The results suggested that ligustrazine could elevate the threshold of thermal nociception through inhibiting the high-voltage gated calcium current and TTX-resistant sodium current of DRG neuron .in the rat.

  1. All-optical gates based on photonic crystal resonators

    Science.gov (United States)

    Moille, Grégory; De Rossi, Alfredo; Combrié, Sylvain

    2016-04-01

    We briefly review the technology of advanced nonlinear resonators for all-optical gating with a specific focus on the application of high-performance signal sampling and on the properties of III-V semiconductor photonic crystals

  2. Power Gating Based Ground Bounce Noise Reduction

    Directory of Open Access Journals (Sweden)

    M. Uma Maheswari

    2014-08-01

    Full Text Available As low power circuits are most popular the decrease in supply voltage leads to increase in leakage power with respect to the technology scaling. So for removing this kind of leakages and to provide a better power efficiency many power gating techniques are used. But the leakage due to ground connection to the active part of the circuit is very high rather than all other leakages. As it is mainly due to the back EMF of the ground connection it was called it as ground bounce noise. To reduce this noise different methodologies are designed. In this paper the design of such an efficient technique related to ground bounce noise reduction using power gating circuits and comparing the results using DSCH and Microwind low power tools. In this paper the analysis of adders such as full adders using different types of power gated circuits using low power VLSI design techniques and to present the comparison results between different power gating methods.

  3. High-rate quantum key distribution over 100 km using ultra-low-noise, 2-GHz sinusoidally gated InGaAs/InP avalanche photodiodes.

    Science.gov (United States)

    Namekata, N; Takesue, H; Honjo, T; Tokura, Y; Inoue, S

    2011-05-23

    We have demonstrated quantum key distribution (QKD) over 100 km using single-photon detectors based on InGaAs/InP avalanche photodiodes (APDs). We implemented the differential phase shift QKD (DPS-QKD) protocol with electrically cooled and 2-GHz sinusoidally gated APDs. The single-photon detector has a dark count probability of 2.8 × 10(-8) (55 counts per second) with a detection efficiency of 6 %, which enabled us to achieve 24 kbit/s secure key rate over 100 km of optical fiber. The DPS-QKD system offers better performances in a practical way than those achieved using superconducting single-photon detectors. Moreover, the distance that secure keys against the general individual attacks can be distributed has been extended to 160 km.

  4. High temperature (1000 °C) compatible Y-La-Si-O silicate gate dielectric in direct contact with Si with 7.7 A˚ equivalent oxide thickness

    Science.gov (United States)

    Dubourdieu, C.; Cartier, E.; Bruley, J.; Hopstaken, M.; Frank, M. M.; Narayanan, V.

    2011-06-01

    Yttrium lanthanum silicate was formed in direct contact with silicon after a rapid thermal annealing at 1000 °C in metal-oxide-semiconductor capacitors leading to an equivalent oxide thickness (EOT) of 7.7 Å. This represents one of the lowest EOT value reported for a gate-first process with non Hf-based dielectric. The silicate is formed by interdiffusion of La2O3 and YOx layers and interfacial SiO2 consumption. Yttrium incorporation reduces the leakage current density as well as the large negative flatband voltage (Vfb) shift that is associated with lanthanide-based dielectrics. The Vfb value can be appropriately tuned for n-type field-effect transistor operation by changing the silicate composition.

  5. Hetero-gate-Dielectric Symmetric U-shaped gate tunnel FET

    Science.gov (United States)

    Tajally, Mohammad Bagher; Karami, Mohammad Azim

    2017-10-01

    Heterogeneous gate dielectric is used in a nanoscale symmetric U-shaped gate tunnel FET (SUTFET), which resulted in ION, IOFF, subthreshold swing (SS), and Iambipolar enhancement. ION of 1.5 × 10-5 A/μm, IOFF of 6 × 10-12 A/μm, average subthreshold swing of (SS) 19.83 mV/decade from 0 V high-k dielectric close to the source and low-k dielectric in the vicinity of drain. The gate dielectric engineering shows characteristic enhancement in compare to SUTFET with single gate dielectric material. The strong coupling between the gate and transistor channel near the source results in reduced potential barrier width in tunnel junction, which leads to higher ION and lower subthreshold swing. Moreover, the presence of low-k dielectric near the drain reduces ambipolar current by increasing potential barrier height. This improved SUTFET characteristics makes it suitable for the usage in digital circuits due to reduced ambipolar response.

  6. Piezoconductivity of gated suspended graphene

    NARCIS (Netherlands)

    Medvedyeva, M.V.; Blanter, Y.M.

    2011-01-01

    We investigate the conductivity of graphene sheet deformed over a gate. The effect of the deformation on the conductivity is twofold: The lattice distortion can be represented as pseudovector potential in the Dirac equation formalism, whereas the gate causes inhomogeneous density redistribution. We

  7. Works close to gate B

    CERN Multimedia

    GS Department

    2011-01-01

    In connection to the TRAM project, drainage works will be carried out close to gate B until the end of next week. In order to avoid access problems, if arriving by car, please use gates A and E. Department of General Infrastructure Services (GS) GS-SE Group

  8. Cooperative gating between ion channels.

    Science.gov (United States)

    Choi, Kee-Hyun

    2014-01-01

    Cooperative gating between ion channels, i.e. the gating of one channel directly coupled to the gating of neighboring channels, has been observed in diverse channel types at the single-channel level. Positively coupled gating could enhance channel-mediated signaling while negative coupling may effectively reduce channel gating noise. Indeed, the physiological significance of cooperative channel gating in signal transduction has been recognized in several in vivo studies. Moreover, coupled gating of ion channels was reported to be associated with some human disease states. In this review, physiological roles for channel cooperativity and channel clustering observed in vitro and in vivo are introduced, and stimulation-induced channel clustering and direct channel cross linking are suggested as the physical mechanisms of channel assembly. Along with physical clustering, several molecular mechanisms proposed as the molecular basis for functional coupling of neighboring channels are covered: permeant ions as a channel coupling mediator, concerted channel activation through the membrane, and allosteric mechanisms. Also, single-channel analysis methods for cooperative gating such as the binomial analysis, the variance analysis, the conditional dwell time density analysis, and the maximum likelihood fitting analysis are reviewed and discussed.

  9. Penn State DOE GATE Program

    Energy Technology Data Exchange (ETDEWEB)

    Anstrom, Joel

    2012-08-31

    The Graduate Automotive Technology Education (GATE) Program at The Pennsylvania State University (Penn State) was established in October 1998 pursuant to an award from the U.S. Department of Energy (U.S. DOE). The focus area of the Penn State GATE Program is advanced energy storage systems for electric and hybrid vehicles.

  10. Learning to Baseline Business Technology

    Directory of Open Access Journals (Sweden)

    David Gore

    2013-10-01

    Full Text Available bills, sign multi-­‐year contracts, and make purchasing decisions without having an overall technology plan. That plan includes a technology baseline to fully assess existing technology. A CIO's goal is to align IT with business goals. Businesses must know total cost of ownership and the return on investment for all technology purchases and monthly costs. A business must also be able to manage technology assets and best utilize resources across the business. Teaching students to baseline technology will enable them to track and manage costs, discover errors and waste, and consolidate and improve existing technology.

  11. Logic Gates with Ion Transistors

    CERN Document Server

    Grebel, Haim

    2016-01-01

    Electronic logic gates are the basic building blocks of every computing and micro controlling system. Logic gates are made of switches, such as diodes and transistors. Ion-selective, ionic switches may emulate electronic switches [1-8]. If we ever want to create artificial bio-chemical circuitry, then we need to move a step further towards ion-logic circuitry. Here we demonstrate ion XOR and OR gates with electrochemical cells, and specifically, with two wet-cell batteries. In parallel to vacuum tubes, the batteries were modified to include a third, permeable and conductive mid electrode (the gate), which was placed between the anode and cathode in order to affect the ion flow through it. The key is to control the cell output with a much smaller biasing power, as demonstrated here. A successful demonstration points to self-powered ion logic gates.

  12. Gating system design for the space device case using T-Flex CAD

    Directory of Open Access Journals (Sweden)

    Ayusheev Munkhe-Zul

    2017-01-01

    Full Text Available The judicious selection of gating system for the consumable pattern takes a lot of time, labour and other significant resources. The modern design technologies provide quick and effective ways for gating system calculation and casting process simulation. Gating system modeling allows estimating different kinds of defects which can occur at the developing stage of casting process. Moreover, it is possible to modify the whole gating system configuration if some parameters are changed. Analyzing these data and modifying the gating system characteristics high quality of castings can be achieved.

  13. Enhanced architectures for room-temperature reversible logic gates in graphene

    Science.gov (United States)

    Dragoman, Daniela; Dragoman, Mircea

    2014-09-01

    We show that reversible two- and three-input logic gates, such as the universal Toffoli gate, can be implemented with three tilted gate electrodes patterned on a monolayer graphene flake. These reversible gates are based on the unique properties of ballistic charge carriers in graphene, which induce bandgaps in transmission for properly chosen potential barriers. The enhanced architectures for reversible logic gate implementation proposed in this paper offer a remarkable design simplification compared to standard approaches based on field-effect transistor circuits, as well as potential high-frequency operation.

  14. Universal gates based on targeted phase shifts in a 3D neutral atom array

    Science.gov (United States)

    Kumar, Aishwarya; Wang, Yang; Wu, Tsung-Yao; Weiss, David

    2016-05-01

    We demonstrate a new approach to making targeted single qubit gates using Cesium atoms in a 5x5x5 3D neutral atom array. It combines targeted AC Zeeman phase shifts with global microwave pulses to produce arbitrary single qubit gates. Non-targeted atoms are left virtually untouched by the gates. We have addressed 48 sites, targeted individually, in a 40% full array. We have also performed Randomized Benchmarking to characterize the fidelity and crosstalk errors of this gate. These gates are highly insensitive to addressing beam imperfections and can be applied to other systems and geometries. Supported by NSF.

  15. Electrical characteristics of metal–insulator–semiconductor and metal–insulator–semiconductor–insulator–metal capacitors under different high-$k$ gate dielectrics investigated in the semi-classical and quantum mechanical models

    Indian Academy of Sciences (India)

    SLAH HLALI; NEILA HIZEM; ADEL KALBOUSSI

    2017-02-01

    In this paper the electrical characteristics of metal–insulator–semiconductor (MIS) and metal–insulator–semiconductor–insulator–metal (MISIM) capacitors with (100)-oriented p-type silicon as a substrate under different high-$k$ gate dielectrics (SiO$_2$, HfO$_2$, La$_2$O$_3$ and TiO$_2$) are investigated in the semi-classical and quantum mechanical models. We review the quantum correction in the inversion layer charge density for p-doped structures. The purpose of this paper is to point out the differences between the semi-classical and quantum mechanical charge descriptions at the insulator–semiconductor interface and the effect of the type of oxide and their position (gate oxide or buried oxide) in our structures. In particular, capacitance–voltage ($C–V$), relative position of the sub-band energies and their wavefunctions are studied to examine qualitatively and quantitatively the electron states and charging mechanisms in our devices. We find that parameters such as threshold voltage and device trans-conductance are enormously sensitive to the proper treatment of quantization effects.

  16. Stability control of gate groups in deep wells

    Energy Technology Data Exchange (ETDEWEB)

    Zhi-biao Guo; Ping-ye Guo; Mao-hong Huang; Yin-gen Liu [China University of Mining & Technology, Beijing (China). School of Geotechnical Engineering

    2009-03-15

    In order to study stability control methods for a deep gate group under complex stresses, we conducted field investigations and analyses of reasons for damage in the Xuzhou coal mining district. Three reasons are proposed: deep high stress, improper roadway layout and support technology. The stability control countermeasures of the gate group consist of an intensive design technology and responding bolt-mesh-anchor truss support technology. Our research method has been applied at the -1000 m level gate group in Qishan Coal Mine. Suitable countermeasures have been tested by field monitoring. 16 refs., 9 figs.

  17. Stability control of gate groups in deep wells

    Institute of Scientific and Technical Information of China (English)

    GUO Zhi-biao; GUO Ping-ye; HUANG Mao-hong; LIU Yin-gen

    2009-01-01

    In order to study stability control methods for a deep gate group under complex stresses, we conducted field investiga-tions and analyses of reasons for damage in the Xuzhou mining district. Three reasons are proposed: deep high stress, improper roadway layout and support technology. The stability control countermeasures of the gate group consist of an intensive design technology and responding bolt-mesh-anchor truss support technology. Our research method has been applied at the -1000 m level gate group in Qishan Coal Mine. Suitable countermeasures have been tested by field monitoring.

  18. Fast synthesis of the Fredkin gate via quantum Zeno dynamics

    Science.gov (United States)

    Shao, Xiao-Qiang; Zheng, Tai-Yu; Zhang, Shou

    2012-12-01

    We propose a scheme for fast synthesizing the Fredkin gate with rf SQUID qubits. This scheme utilizes the quantum Zeno dynamics induced by continuous couplings and the non-identical couplings between SQUIDs and superconducting cavity. The effects of decoherence on the performance for the gate are analyzed in virtue of master equation and non-unitary evolution with full Hamiltonian. The strictly numerical simulation shows that the fidelity of this Fredkin gate is relatively high corresponding to current typical experimental parameters. Furthermore, an equivalent physical model is also constructed in an array of coupled cavities.

  19. Unconventional geometric quantum phase gates with a cavity QED system

    Science.gov (United States)

    Zheng, Shi-Biao

    2004-11-01

    We propose a scheme for realizing two-qubit quantum phase gates via an unconventional geometric phase shift with atoms in a cavity. In the scheme the atoms interact simultaneously with a highly detuned cavity mode and a classical field. The atoms undergo no transitions during the gate operation, while the cavity mode is displaced along a circle in the phase space, aquiring a geometric phase conditional upon the atomic state. Under certain conditions, the atoms are disentangled with the cavity mode and thus the gate is insensitive to both the atomic spontaneous emission and the cavity decay.

  20. All-Optical Reversible Hybrid New Gate using TOAD

    Directory of Open Access Journals (Sweden)

    Goutam Kumar Maity

    2014-03-01

    Full Text Available Reversible logic is emerged as a promising computing paradigm with applications in low-power CMOS, quantum computing, optical computing and nanotechnology. Optical logic gates become potential component to work at macroscopic (light pulses carry information, or quantum (single photon carries information levels with high efficiency. In this paper, we propose a novel scheme of Hybrid new gate realization in all-optical domain. Simulation results verify the functionality of the gate as well as reversibility. Approximate insertion power loss in dB is also reported for the Gaussian incident and control pulse.

  1. Baseline Removal From EMG Recordings

    Science.gov (United States)

    2007-11-02

    a time-varying baseline contamination. Acknowledgements: Work funded by the Departamento de Salud del Gobierno de Navarrra and by a Spanish MEC...Name(s) and Address(es) Departamento de Ingenieria Electra y Electronica Universidad Publica de Navarra Pamplona, Spain Performing Organization Report

  2. Redox control of 20S proteasome gating.

    Science.gov (United States)

    Silva, Gustavo M; Netto, Luis E S; Simões, Vanessa; Santos, Luiz F A; Gozzo, Fabio C; Demasi, Marcos A A; Oliveira, Cristiano L P; Bicev, Renata N; Klitzke, Clécio F; Sogayar, Mari C; Demasi, Marilene

    2012-06-01

    The proteasome is the primary contributor in intracellular proteolysis. Oxidized or unstructured proteins can be degraded via a ubiquitin- and ATP-independent process by the free 20S proteasome (20SPT). The mechanism by which these proteins enter the catalytic chamber is not understood thus far, although the 20SPT gating conformation is considered to be an important barrier to allowing proteins free entrance. We have previously shown that S-glutathiolation of the 20SPT is a post-translational modification affecting the proteasomal activities. The goal of this work was to investigate the mechanism that regulates 20SPT activity, which includes the identification of the Cys residues prone to S-glutathiolation. Modulation of 20SPT activity by proteasome gating is at least partially due to the S-glutathiolation of specific Cys residues. The gate was open when the 20SPT was S-glutathiolated, whereas following treatment with high concentrations of dithiothreitol, the gate was closed. S-glutathiolated 20SPT was more effective at degrading both oxidized and partially unfolded proteins than its reduced form. Only 2 out of 28 Cys were observed to be S-glutathiolated in the proteasomal α5 subunit of yeast cells grown to the stationary phase in glucose-containing medium. We demonstrate a redox post-translational regulatory mechanism controlling 20SPT activity. S-glutathiolation is a post-translational modification that triggers gate opening and thereby activates the proteolytic activities of free 20SPT. This process appears to be an important regulatory mechanism to intensify the removal of oxidized or unstructured proteins in stressful situations by a process independent of ubiquitination and ATP consumption. Antioxid. Redox Signal. 16, 1183-1194.

  3. Effects of Ti addition and annealing on high-k Gd{sub 2}O{sub 3} sensing membranes on polycrystalline silicon for extended-gate field-effect transistor applications

    Energy Technology Data Exchange (ETDEWEB)

    Kao, Chyuan Haur [Department of Electronic Engineering, Chang Gung University, Taoyuan 333, Taiwan, ROC (China); Chen, Hsiang, E-mail: hchen@ncnu.edu.tw [Department of Applied Materials and Optoelectronic Engineering, National Chi Nan University, Puli 545, Taiwan, ROC (China); Huang, Chuan-Yu [Department of Electronic Engineering, Chang Gung University, Taoyuan 333, Taiwan, ROC (China)

    2013-12-01

    Gadolinium oxide (Gd{sub 2}O{sub 3}) and gadolinium titanium oxide (Gd{sub 2}TiO{sub 5}) sensing membranes were deposited on polysilicon substrates and applied in the extended-gate field-effect transistor (EGFET) for pH detection. Effects of Ti addition and annealing on the sensing films have been investigated by multiple material analyses and electrical characterizations. The sensing performance could be improved with proper post-annealing and Ti addition because of reinforcements of crystalline structures and electrical reliability. Gd{sub 2}TiO{sub 5} sensing membranes annealed at a temperature of 800 °C could achieve high sensitivity, high linearity, low hysteresis voltage, and a low drift ratio, which is promising for future generation of bio-medical device applications.

  4. Improved linearity and reliability in GaN metal-oxide-semiconductor high-electron-mobility transistors using nanolaminate La2O3/SiO2 gate dielectric

    Science.gov (United States)

    Hsu, Ching-Hsiang; Shih, Wang-Cheng; Lin, Yueh-Chin; Hsu, Heng-Tung; Hsu, Hisang-Hua; Huang, Yu-Xiang; Lin, Tai-Wei; Wu, Chia-Hsun; Wu, Wen-Hao; Maa, Jer-Shen; Iwai, Hiroshi; Kakushima, Kuniyuki; Chang, Edward Yi

    2016-04-01

    Improved device performance to enable high-linearity power applications has been discussed in this study. We have compared the La2O3/SiO2 AlGaN/GaN metal-oxide-semiconductor high-electron-mobility transistors (MOS-HEMTs) with other La2O3-based (La2O3/HfO2, La2O3/CeO2 and single La2O3) MOS-HEMTs. It was found that forming lanthanum silicate films can not only improve the dielectric quality but also can improve the device characteristics. The improved gate insulation, reliability, and linearity of the 8 nm La2O3/SiO2 MOS-HEMT were demonstrated.

  5. Thermally deposited Ag-doped CdS thin film transistors with high-k rare-earth oxide Nd{sub 2}O{sub 3} as gate dielectric

    Energy Technology Data Exchange (ETDEWEB)

    Gogoi, P., E-mail: paragjyoti_g@rediffmail.com [Sibsagar College, Material Science Laboratory, Department of Physics (India)

    2013-03-15

    The performance of thermally deposited CdS thin film transistors doped with Ag has been reported. Ag-doped CdS thin films have been prepared using chemical method. High dielectric constant rare earth oxide Nd{sub 2}O{sub 3} has been used as gate insulator. The thin film trasistors are fabricated in coplanar electrode structure on ultrasonically cleaned glass substrates with a channel length of 50 {mu}m. The thin film transistors exhibit a high mobility of 4.3 cm{sup 2} V{sup -1} s{sup -1} and low threshold voltage of 1 V. The ON-OFF ratio of the thin film transistors is found as 10{sup 5}. The TFTs also exhibit good transconductance and gain band-width product of 1.15 Multiplication-Sign 10{sup -3} mho and 71 kHz respectively.

  6. Gated Si nanowires for large thermoelectric power factors

    Energy Technology Data Exchange (ETDEWEB)

    Neophytou, Neophytos, E-mail: N.Neophytou@warwick.ac.uk [School of Engineering, University of Warwick, Coventry CV4 7AL (United Kingdom); Kosina, Hans [Institute for Microelectronics, Vienna University of Technology, Gusshausstrasse 27-29/E360, Vienna A-1040 (Austria)

    2014-08-18

    We investigate the effect of electrostatic gating on the thermoelectric power factor of p-type Si nanowires (NWs) of up to 20 nm in diameter in the [100], [110], and [111] crystallographic transport orientations. We use atomistic tight-binding simulations for the calculation of the NW electronic structure, coupled to linearized Boltzmann transport equation for the calculation of the thermoelectric coefficients. We show that gated NW structures can provide ∼5× larger thermoelectric power factor compared to doped channels, attributed to their high hole phonon-limited mobility, as well as gating induced bandstructure modifications which further improve mobility. Despite the fact that gating shifts the charge carriers near the NW surface, surface roughness scattering is not strong enough to degrade the transport properties of the accumulated hole layer. The highest power factor is achieved for the [111] NW, followed by the [110], and finally by the [100] NW. As the NW diameter increases, the advantage of the gated channel is reduced. We show, however, that even at 20 nm diameters (the largest ones that we were able to simulate), a ∼3× higher power factor for gated channels is observed. Our simulations suggest that the advantage of gating could still be present in NWs with diameters of up to ∼40 nm.

  7. The curvHDR method for gating flow cytometry samples

    Directory of Open Access Journals (Sweden)

    Wand Matthew P

    2010-01-01

    Full Text Available Abstract Background High-throughput flow cytometry experiments produce hundreds of large multivariate samples of cellular characteristics. These samples require specialized processing to obtain clinically meaningful measurements. A major component of this processing is a form of cell subsetting known as gating. Manual gating is time-consuming and subjective. Good automatic and semi-automatic gating algorithms are very beneficial to high-throughput flow cytometry. Results We develop a statistical procedure, named curvHDR, for automatic and semi-automatic gating. The method combines the notions of significant high negative curvature regions and highest density regions and has the ability to adapt well to human-perceived gates. The underlying principles apply to dimension of arbitrary size, although we focus on dimensions up to three. Accompanying software, compatible with contemporary flow cytometry infor-matics, is developed. Conclusion The method is seen to adapt well to nuances in the data and, to a reasonable extent, match human perception of useful gates. It offers big savings in human labour when processing high-throughput flow cytometry data whilst retaining a good degree of efficacy.

  8. Measurement of time delays in gated radiotherapy for realistic respiratory motions.

    Science.gov (United States)

    Chugh, Brige P; Quirk, Sarah; Conroy, Leigh; Smith, Wendy L

    2014-09-01

    Gated radiotherapy is used to reduce internal motion margins, escalate target dose, and limit normal tissue dose; however, its temporal accuracy is limited. Beam-on and beam-off time delays can lead to treatment inefficiencies and/or geographic misses; therefore, AAPM Task Group 142 recommends verifying the temporal accuracy of gating systems. Many groups use sinusoidal phantom motion for this, under the tacit assumption that use of sinusoidal motion for determining time delays produces negligible error. The authors test this assumption by measuring gating time delays for several realistic motion shapes with increasing degrees of irregularity. Time delays were measured on a linear accelerator with a real-time position management system (Varian TrueBeam with RPM system version 1.7.5) for seven motion shapes: regular sinusoidal; regular realistic-shape; large (40%) and small (10%) variations in amplitude; large (40%) variations in period; small (10%) variations in both amplitude and period; and baseline drift (30%). Film streaks of radiation exposure were generated for each motion shape using a programmable motion phantom. Beam-on and beam-off time delays were determined from the difference between the expected and observed streak length. For the system investigated, all sine, regular realistic-shape, and slightly irregular amplitude variation motions had beam-off and beam-on time delays within the AAPM recommended limit of less than 100 ms. In phase-based gating, even small variations in period resulted in some time delays greater than 100 ms. Considerable time delays over 1 s were observed with highly irregular motion. Sinusoidal motion shapes can be considered a reasonable approximation to the more complex and slightly irregular shapes of realistic motion. When using phase-based gating with predictive filters even small variations in period can result in time delays over 100 ms. Clinical use of these systems for patients with highly irregular patterns of motion is

  9. AlGaN/GaN metal-insulator-semiconductor high-electron mobility transistors with high on/off current ratio of over 5 × 1010 achieved by ozone pretreatment and using ozone oxidant for Al2O3 gate insulator

    Science.gov (United States)

    Tokuda, Hirokuni; Asubar, Joel T.; Kuzuhara, Masaaki

    2016-12-01

    This letter describes DC characteristics of AlGaN/GaN metal-insulator-semiconductor high-electron-mobility transistors (MIS-HEMTs) with Al2O3 deposited by atomic layer deposition (ALD) as gate dielectric. Comparison was made for the samples deposited using ozone (O3) or water as oxidant. The effect of pretreatment, where O3 was solely supplied prior to depositing Al2O3, was also investigated. The MIS-HEMT with O3 pretreatment and Al2O3 gate dielectric deposited using O3 as the oxidant exhibited the most desirable characteristics with an excellent high on/off current ratio of 7.1 × 1010, and a low sub-threshold swing (SS) of 73 mV/dec.

  10. Gated Detection Measurements of Phosphorescence Lifetimes

    Directory of Open Access Journals (Sweden)

    Yordan Kostov

    2004-10-01

    Full Text Available A low-cost, gated system for measurements of phosphorescence lifetimes is presented. An extensive description of the system operating principles and metrological characteristics is given. Remarkably, the system operates without optical filtering of the LED excitation source. A description of a practical system is also given and its performance is discussed. Because the device effectively suppresses high-level background fluorescence and scattered light, it is expected to find wide-spread application in bioprocess, environmental and biomedical fields.

  11. Study on Preparation of High-k Organic-Inorganic Thin Film for Organic-Inorganic Thin Film Transistor Gate Dielectric Application

    Science.gov (United States)

    Lee, Wen-Hsi; Liu, Chao-Te; Lee, Ying-Chieh

    2012-06-01

    A simple solution-based deposition technique combined with spin-coating is a plausible way to prepare ultra-thin organic-inorganic nanocomposite films. In this study, we describe the spin-coating deposition of a colloidal nanoparticle suspension to obtain an ultra-thin organic-inorganic composite film as a gate insulator for organic thin film transistor (O-TFT) application. To obtain a homogenous organic-inorganic composite film, well-dispersed TiO2 nanoparticles in γ-butyrolactone and polyimide are important; therefore, several dispersants were assessed on the basis of the measurement of the rheological behavior of slurries. The thickness of the organic-inorganic composite film is mainly determined by the speed of spin-coating and viscosity of slurries. An approximately 4000-Å-thick nanocomposite film with homogeneous distribution of TiO2 nanoparticles in polyimide and low roughness was obtained after curing at 200 °C, resulting in a low leakage current density of the nano-composite film, when less than 2 vol % TiO2 nanoparticles were well dispersed in polyimide slurry. The dielectric constant of the organic-inorganic nanocomposite increases with increasing TiO2 content in polyimide, being situated in the range between 4 and 5.

  12. Mode S Baseline Radar Tracking.

    Science.gov (United States)

    1982-11-01

    range units and 20 azimuth units) overlaying the position of the beacon reports. In the cases analyzed where beacon reports were not radar reinforced ...82/53 j~ C ~ 7 C _ _ _ _ _ _ 4. Title end Su.btitle 5. Neget at. November 1982 MDDE S BASELINE RADAR TRACKIN4G 6. Poelin Orgeuianti.. Cede ACT-100...Ground Clutter 33 Mode S/ARTS III 100-Scan False Radar Track Summary 74 34 Percent Beacon Radar Reinforcement 77 vii INTRODUCTION PURPOSE. The purpose of

  13. Growth and Current Leakage Characteristics of SrHfON High-k Gate Dielectric Films%SrHfON高κ栅介质薄膜的漏电特性研究

    Institute of Scientific and Technical Information of China (English)

    王雪梅; 刘正堂; 冯丽萍

    2013-01-01

    采用射频反应磁控溅射法在p-Si(100)衬底上成功制备出SrHfON高k栅介质薄膜,并研究了Au/SrHfON/Si MOS电容的漏电流机制及应力感应漏电流(SILC)效应.结果表明,MOS电容的漏电流密度随N2流量的增加而减小.在正栅压下,漏电流主要由Schottky发射机制引起;在负栅压下,漏电流机制在低、中、高栅电场区时分别为Schottky发射、F-P发射和F-N隧穿机制.同时,Au/SrHfON/Si MOS电容表现出明显的SILC效应,经恒压应力后薄膜在正栅压下的漏电流由Schouky发射和F-P发射机制共同作用,且后者占主导地位.%The SrHfON highgate dielectric films,deposited by RF reactive magnetron sputtering on p-type Si (100)substrates,were used to fabricate the Au/SrHfON/Si MOS capacitor.The impacts of the growth conditions on the leakage current density were evaluated with X-ray photoelectron spectroscopy and conventional proves.The leakage current conduction mechanisms and the stress induced leakage current(SILC) effect of the MOS capacitor were studied.The leakage current density of the MOS capacitor was found to decrease with an increase of N2 flow rate.At a positive bias of the metal gate,the leakage current mainly originated from Schottky emission,but at a negative bias,the leakage current in the low-,medium-and high-gate voltage ranges resulted from Schottky emission,Poole-Franel (F-P) emission and Fowler-Nord-heim (F-N) tunneling,respectively.In addition,the SILC effect was found to dominate the Au/SrHfON/Si MOS capacitor;but after being stressel by a constant voltage,Schottky emission outperforms F-P emission in generating the leakage current.

  14. Asbestos Surveillance Program Aachen (ASPA): initial results from baseline screening for lung cancer in asbestos-exposed high-risk individuals using low-dose multidetector-row CT.

    Science.gov (United States)

    Das, Marco; Mühlenbruch, Georg; Mahnken, Andreas H; Hering, K G; Sirbu, H; Zschiesche, W; Knoll, Lars; Felten, Michael K; Kraus, Thomas; Günther, Rolf W; Wildberger, Joachim E

    2007-05-01

    The purpose of this study was to assess the prevalence of lung cancer in a high-risk asbestos-exposed cohort using low-dose MDCT. Of a population of 5,389 former power-plant workers, 316 were characterized as individuals at highest risk for lung cancer according to a lung-cancer risk model including age, asbestos exposure and smoking habits. Of these 316, 187 (mean age: 66.6 years) individuals were included in a prospective trial. Mean asbestos exposure time was 29.65 years and 89% were smokers. Screening was performed on a 16-slice MDCT (Siemens) with low-dose technique (10/20 mAs(eff.); 1 mm/0.5 mm increment). In addition to soft copy PACS reading analysis on a workstation with a dedicated lung analysis software (LungCARE; Siemens) was performed. One strongly suspicious mass and eight cases of histologically proven lung cancer were found plus 491 additional pulmonary nodules (average volume: 40.72 ml, average diameter 4.62 mm). Asbestos-related changes (pleural plaques, fibrosis) were visible in 80 individuals. Lung cancer screening in this high-risk cohort showed a prevalence of lung cancer of 4.28% (8/187) at baseline screening with an additional large number of indeterminate pulmonary nodules. Low-dose MDCT proved to be feasible in this highly selected population.

  15. A chemosensor showing discriminating fluorescent response for highly selective and nanomolar detection of Cu²⁺ and Zn²⁺ and its application in molecular logic gate.

    Science.gov (United States)

    Fegade, Umesh A; Sahoo, Suban K; Singh, Amanpreet; Singh, Narinder; Attarde, Sanjay B; Kuwar, Anil S

    2015-05-04

    A fluorescent based receptor (4Z)-4-(4-diethylamino)-2-hydroxybenzylidene amino)-1,2dihydro-1,5-dimethyl-2-phenylpyrazol-3-one (receptor 3) was developed for the highly selective and sensitive detection of Cu(2+) and Zn(2+) in semi-aqueous system. The fluorescence of receptor 3 was enhanced and quenched, respectively, with the addition of Zn(2+) and Cu(2+) ions over other surveyed cations. The receptor formed host-guest complexes in 1:1 stoichiometry with the detection limit of 5 nM and 15 nM for Cu(2+) and Zn(2+) ions, respectively. Further, we have effectively utilized the two metal ions (Cu(2+) and Zn(2+)) as chemical inputs for the manufacture of INHIBIT type logic gate at molecular level using the fluorescence responses of receptor 3 at 450 nm. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Fabrication of normally-off AlGaN/GaN metal-insulator-semiconductor high-electron-mobility transistors by photo-electrochemical gate recess etching in ionic liquid

    Science.gov (United States)

    Zhang, Zhili; Qin, Shuangjiao; Fu, Kai; Yu, Guohao; Li, Weiyi; Zhang, Xiaodong; Sun, Shichuang; Song, Liang; Li, Shuiming; Hao, Ronghui; Fan, Yaming; Sun, Qian; Pan, Gebo; Cai, Yong; Zhang, Baoshun

    2016-08-01

    We characterized an ionic liquid (1-butyl-3-methylimidazolium nitrate, C8H15N3O3) as a photo-electrochemical etchant for fabricating normally-off AlGaN/GaN metal-insulator-semiconductor high-electron-mobility transistors (MIS-HEMTs). Using the ionic liquid, we achieved an etching rate of ˜2.9 nm/min, which is sufficiently low to facilitate good etching control. The normally-off AlGaN/GaN MIS-HEMT was fabricated with an etching time of 6 min, with the 20 nm low-pressure chemical vapor deposition (LPCVD) silicon nitride (Si3N4) gate dielectric exhibiting a threshold voltage shift from -10 to 1.2 V, a maximum drain current of more than 426 mA/mm, and a breakdown voltage of 582 V.

  17. Reversible logic gates on Physarum Polycephalum

    Energy Technology Data Exchange (ETDEWEB)

    Schumann, Andrew [University of Information Technology and Management, Sucharskiego 2, Rzeszow, 35-225 (Poland)

    2015-03-10

    In this paper, we consider possibilities how to implement asynchronous sequential logic gates and quantum-style reversible logic gates on Physarum polycephalum motions. We show that in asynchronous sequential logic gates we can erase information because of uncertainty in the direction of plasmodium propagation. Therefore quantum-style reversible logic gates are more preferable for designing logic circuits on Physarum polycephalum.

  18. Demonstration of a Quantum Nondemolition Sum Gate

    DEFF Research Database (Denmark)

    Yoshikawa, J.; Miwa, Y.; Huck, Alexander;

    2008-01-01

    The sum gate is the canonical two-mode gate for universal quantum computation based on continuous quantum variables. It represents the natural analogue to a qubit C-NOT gate. In addition, the continuous-variable gate describes a quantum nondemolition (QND) interaction between the quadrature compo...

  19. Obesogenic dietary intake in families with 1-year-old infants at high and low obesity risk based on parental weight status: baseline data from a longitudinal intervention (Early STOPP).

    Science.gov (United States)

    Svensson, Viktoria; Sobko, Tanja; Ek, Anna; Forssén, Michaela; Ekbom, Kerstin; Johansson, Elin; Nowicka, Paulina; Westerståhl, Maria; Riserus, Ulf; Marcus, Claude

    2016-03-01

    To compare dietary intake in 1-year-old infants and their parents between families with high and low obesity risk, and to explore associations between infant dietary intake and relative weight. Baseline analyses of 1-year-old infants (n = 193) and their parents participating in a longitudinal obesity intervention (Early STOPP) were carried out. Dietary intake and diet quality indicators were compared between high- and low-risk families, where obesity risk was based on parental weight status. The odds for high diet quality in relation to parental diet quality were determined. Associations between measured infant relative weight and dietary intake were examined adjusting for obesity risk, socio-demographics, and infant feeding. Infant dietary intake did not differ between high- and low-risk families. The parents in high-risk families consumed soft drinks, French fries, and low-fat spread more frequently, and fish and fruits less frequently (p intake of vegetables and fish increased the odds for children being consumers of vegetables (OR 1.7; 95 % CI 1.0-2.9) and fish, respectively (OR 2.5; 95 % CI 1.4-4.4). Infant relative weight was weakly associated with a high intake of milk cereal drink (r = 0.15; p intake, obesity risk, or early feeding patterns. At the age of one, dietary intake in infants is not associated with family obesity risk, nor with parental obesogenic food intake. Milk cereal drink consumption but no other infant dietary marker reflects relative weight at this young age.

  20. Randomized benchmarking of multiqubit gates.

    Science.gov (United States)

    Gaebler, J P; Meier, A M; Tan, T R; Bowler, R; Lin, Y; Hanneke, D; Jost, J D; Home, J P; Knill, E; Leibfried, D; Wineland, D J

    2012-06-29

    We describe an extension of single-qubit gate randomized benchmarking that measures the error of multiqubit gates in a quantum information processor. This platform-independent protocol evaluates the performance of Clifford unitaries, which form a basis of fault-tolerant quantum computing. We implemented the benchmarking protocol with trapped ions and found an error per random two-qubit Clifford unitary of 0.162±0.008, thus setting the first benchmark for such unitaries. By implementing a second set of sequences with an extra two-qubit phase gate inserted after each step, we extracted an error per phase gate of 0.069±0.017. We conducted these experiments with transported, sympathetically cooled ions in a multizone Paul trap-a system that can in principle be scaled to larger numbers of ions.