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Science china(Technological sciences) 2010年第2期53卷 313-316页

作者： WU ChaoMin1, SHANG JingZhi1, ZHANG BaoPing1,2, ZHANG JiangYong1,3, YU JinZhong1,3 & WANG QiMing1,31 Department of Physics and Semiconductor Photonics Research Center, Xiamen University, Xiamen 361005, china 2 Pen-Tung Sah Micro/Nano Technology Research Center, Xiamen University, Xiamen 361005, china 3 state key laboratory on integrated optoelectronics, institute of semiconductors, chinese academy of sciences, beijing 100083, china 1. Department of Physics and Semiconductor Photonics Research Center Xiamen University Xiamen 361005 China2. Pen-Tung Sah Micro/Nano Technology Research Center Xiamen University Xiamen 361005 China3. State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

We studied the impact of the thickness of GaN buffer layer on the properties of distributed Bragg reflector (DBR) grown by metalorganic chemical vapor deposition (MOCVD). The samples were characterized by using metallographic microscope, transmission electron microscope (TEM), atomic force microscopy (AFM), X-ray diffractometer (XRD) and spectrophotometer. The results show that the thickness of the GaN buffer layer can significantly affect the properties of the DBR structure and there is an optimal thickness of the GaN buffer layer. This work would be helpful for the growth of high quality DBR structures.

关键词： MOCVD DBR high-reflectivity nitride

Impact of thickness of GaN buffer layer on properties of AlN/GaN distributed Bragg reflectors grown by metalorganic chemical vapor deposition

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中国科学:技术科学 2010年第2期 203-203页

We studied the impact of the thickness of GaN buffer layer on the properties of distributed Bragg reflector (DBR) grown by metalorganic chemical vapor deposition (MOCVD). The samples were characterized by using metallographic microscope, transmission electron microscope (TEM), atomic force microscopy (AFM), X-ray diffractometer (XRD) and spectrophoto- meter. The results show that the thickness of the GaN buffer layer can significantly affect the properties of the DBR structure and there is an optimal thickness of the GaN buffer layer. This work would be helpful for the growth of high quality DBR structures.

关键词： MOCVD DBR high-reflectivity nitride

A low-noise fully-differential CMOS preamplifier for neural recording applications

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Science china(Information sciences) 2012年第2期55卷 441-452页

作者： ZHANG Xu,PEI WeiHua,HUANG BeiJu,GUAN Ning & CHEN HongDa state key laboratory on integrated optoelectronics,institute of semiconductors,chinese academy of sciences,beijing 100083,china 1. state key laboratory on integrated optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

A fully-differential bandpass CMOS preamplifier for extracellular neural recording is presented in this *** capacitive-coupled and capacitive-feedback topology is *** describe the main noise sources of the proposed preamplifier and discuss the methods for achieving the lowest input-referred *** preamplifier has a midband gain of 43 dB and a DC gain of ***-3 dB upper cut-off frequency of the preamplifier is 6.8 *** lower cut-off frequency can be adjusted for amplifying the field or action potentials located in different *** has an input-referred noise of 3.36 μVrms integrated from 1 Hz to 6.8 kHz for recording the local field potentials(LFPs)and the mixed neural spikes with a power dissipation of 24.75 μW from 3.3 V *** the passband is configured as 100 Hz-6.8 kHz for only recording spikes,the noise is measured to be 3.01 μ*** 0.115 mm2 prototype chip is designed and fabricated in 0.35-μm N-well CMOS(complementary metal oxide semiconductor)2P4M process.

关键词： neural signal amplifier low noise low power subthreshold circuit design noise efficiency factor(NEF)

A 630dpi dynamic LED display array in standard Si-based CMOS technology

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Science china(Information sciences) 2012年第10期55卷 2409-2416页

作者： DONG Zan ,WANG Wei,HUANG BeiJu,ZHANG Xu,GUAN Ning & CHEN HongDa state key laboratory on integrated optoelectronics,institute of semiconductors,chinese academy of sciences,beijing 100083,china 1. state key laboratory on integrated optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

A novel silicon light emitting diode(LED) display array has been fabricated using 0.35 μm standard CMOS *** this array,an LED and static random access memory(SRAM) are integrated together in a special *** SRAM in each pixel can store the state of the pixel and ensure that the pixel remains lit without persistent *** a result,the control logic is perfectly integrated on the same *** power sources are used to drive the display array because the LEDs operate at high voltage(supply voltage of 9 V),and the current of the whole display array is about 30-60 mA to display common *** display circuit includes digital control logic circuits and SRAM,and requires a supply voltage of 3.3 *** area of a single pixel is 40×40 μm 2,the area of the whole 16×16 LED array is 1 mm 2,and the display density is 630 dpi.

关键词： light emitting diode silicon-based CMOS technology display array

Electron-mediated ferromagnetism in Fe-doped InP:Theory and experiment

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chinese Physics B 2012年第9期21卷 484-488页

作者：董珊朱峰 state key laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of Sciences

We report on the electron-mediated ferromagnetism in Fe-doped InP from both first-principles calculations andexperiments. Theoretically, based on the spin-polarized density functional theory within the Heyd-Scuseria-Ernzerhof （HSE03） approach, we systematically investigate the magnetic properties of Fe-doped InP and predict the existence of electron-mediated ferromagnetism. Experimentally, by diffusing Fe into the n-type InP wafer with thermal annealing at 800 ℃, we observe room-temperature ferromagnetism in InP：Fe, which is in agreement with the theoretical prediction.

关键词： erromagnetism Fe-doped InP first-principles calculations

Dry electrode for the measurement of biopotential signals

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Science china(Information sciences) 2011年第11期54卷 2435-2442页

作者： WANG Yu 1,2,PEI WeiHua 2,GUO Kai 2,GUI Qiang 2,LI XiaoQian 2,CHEN HongDa 2 & YANG JianHong 11 institute of Microelectronics,School of Physical Science and Technology,Lanzhou University Lanzhou 730000,china 2 state key laboratory on integrated optoelectronics,institute of semiconductors,chinese academy of sciences,beijing 100083,china 1. institute of Microelectronics School of Physical Science and Technology Lanzhou University Lanzhou 730000 China2. State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

This paper introduces a kind of silicon-based dry electrode for measuring biological *** uses microneedle arrays to penetrate into the stratum corneum to reduce skin *** dry electrode requires neither skin preparation nor the electrolytic gel,is easy to use and causes no skin *** different technologies are chosen to manufacture microneedle arrays of dry *** is deep dry etching combined with isotropic wet *** other is mechanical dicing combined with chemical wet etching (including isotropic wet etching and anisotropic wet etching).Microneedle arrays are coated with metal and divided into 25 mm 2 as dry electrode *** testing shows that the impedance value of dry electrode can be comparable with that of commercial electrode in the 20 Hz-10 kHz frequency *** steady-state visual evoked potential recording and analysis prove that the dry electrode can be used to detect electroencephalography.

关键词： dry electrode microneedle array dry etching wet etching EEG

Characteristics of InGaN multiple quantum well blue-violet laser diodes

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Science china(Technological sciences) 2006年第6期49卷 727-732页

作者： LI Deyao1, ZHANG Shuming1, WANG Jianfeng1, CHEN Jun1, CHEN Lianghui2, CHONG Ming2, ZHU Jianjun1, ZHAO Degang1, LIU Zongshun1, YANG Hui1 & LIANG Junwu1 1. state key laboratory of integrated optoelectronics, institute of semiconductors, chinese academy of sciences, beijing 100083, china 2. Nano-optoelectronics laboratory, institute of semiconductors, chinese academy of sciences, beijing 100083, china state key laboratory of integrated optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China Nano-optoelectronics laboratory Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

Studies on InGaN multiple quantum well blue-violet laser diodes have been reported. Laser structures with long-period multiple quantum wells were grown by metal-organic chemical vapor deposition. Triple-axis X-ray diffraction (TAXRD) measurements show that the multiple quantum wells were high quality. Ridge waveguide laser diodes were fabricated with cleaved facet mirrors. The laser diodes lase at room temperature under a pulsed current. A threshold current density of 3.3 kA/cm[2]; a characteristic temperature T 0 of 145 K were observed for the laser diode.

关键词： metalorganic chemical vapor deposition (MOCVD), GaN-based laser diodes, multiple quantum well, ridge waveguide, threshold current.

Plastic deformation of nanocrystalline nickel

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Science china(Technological sciences) 2009年第8期52卷 2216-2221页

作者： WU XiaoLei state key laboratory of Nonlinear Mechanics, institute of Mechanics, chinese academy of sciences, beijing 100190, china state key laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

A high-resolution electron microscopy study has uncovered the plastic behavior of accommodating large strains in nanocrystalline (NC) Ni subject to cold rolling at liquid nitrogen temperature. The activation of grain-boundary-mediated-plasticity is evidenced in NC-Ni, including twinning and formation of stacking fault via partial dislocation slips from the grain boundary. The formation and storage of 60? full dislocations are observed inside NC-grains. The grain/twin boundaries act as the barriers of dislocation slips, leading to dislocation pile-up, severe lattice distortion, and formation of sub-grain boundary. The vicinity of grain/twin boundary is where defects preferentially accumulate and likely the favorable place for onset of plastic deformation. The present results indicate the heterogeneous and multiple natures of accommodating plastic strains in NC-grains.

关键词： nanocrystalline metal plastic deformation deformation twinning dislocation microstructure

SILICA-SUPPORTED NICKEL AND ZIRCONIUM CATALYSTS FOR BRANCHED POLYETHYLENE

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chinese Journal of Polymer Science 2003年第4期21卷 453-458页

作者：孙文华 state key laboratory of Engineering Plastics The Center for Molecular sciences institute of Chemistry chinese academy of sciences beijing 100080 china chinese Acad Sci Inst Chem Ctr Mol Sci State Key Lab Engn Plast Beijing 100080 Peoples R China

8-Aminoquinoline nickel dichloride and bis(cyclopentadienyl)zirconium dichloride (Cp_2ZrCl_2) were supportedsimultaneously on silica to produce branched polyethylene successfully by combined polymerization. The supportedpolymerization results showed that the molecular weight of polyethylene increased while the molecular weight distributionbecame wider and the molecular chains of oligomers remaning in the final solution became shorter as compared to theoligomers obtained in polymerization processes with pure 8-aminoquinoline nickel dichloride catalysis, as well as theCp_2ZrCl_2 and nickel combination system. With decreasing amount of Ni catalyst in the supported catalyst, the molecular chains of oligomers in the resulting solution became shorter, while α-olefin selectivity increased.

关键词： 8-Aminoquinoline nickel dichloride, Cp_2ZrCl_2 Silica supported catalysts Branched polyethylene

CORRECTION METHODS FOR STEADY INCOMPRESSIBLE FLOWS

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Journal of Computational Mathematics 1999年第4期17卷 419-424页

作者： Jian Li(state key laboratory of Scientific and Engineering Computing, ICMSEC, chinese academy of sciences, beijing 100080, china) 中科院计算数学与科学工程计算所科学与工程计算国家重点实验室北京

Correction methods for the steady semi-periodic motion of incompressible fluid are investigated. The idea is similar to the influence matrix to solve the lack of vorticity boundary conditions. For any given boundary condition of the vorticity, the coupled vorticity-stream function formulation is solved. Then solve the governing equations with the correction boundary conditions to improve the solution. These equations are numerically solved by Fourier series truncation and finite difference method. The two numerical techniques are employed to treat the non-linear terms. The first method for small Reynolds number R equals 0-50 has the same results as that in M. Anwar and S.C.R. Dennis' report. The second one for R greater than 50 obtains the reliable results. (Author abstract) 4 Refs.

关键词： incompressible flow vorticity stream function numerical solution