958 resultados para Pin.
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The semiconductor photonics and optoelectronics which have a great significance in the development of advanced high technology of information systems will be discussed in this paper. The emphasis will be put on the recent research carried out in our laboratory in enhanced luminescence from low dimensional materials such as SiGe/Si and Er-doped Si-rich SiO2/Si and Er-doped SixNy/Si. A ring shape waveguide structure, used to promote the effective absorption coefficient in PIN photodetector for 1.3 mu m wavelength and a resonant cavity enhanced structure, used to improve the quantum efficiency and response in heterostructure photo-transistor (HPT), are also proposed in this paper.
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本书从光电子器件及其在光通信领域的应用出发,介绍了甚短距离光传输技术的组成、原理、实现方案、技术性能、关键技术以及在高速互连领域内的应用等。本书重点阐述了垂直腔面发射激光器的原理、工艺和特性;10gb/s和40gb/s传输方案的具体实现及其性能指标;甚短距离光传输涉及到的各项关键技术,如新型多模光纤技术、cwdm复用技术、硅探测器技术、高速光电集成(oeic)技术以及相关高速网络技术等。
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微电子技术与光电子技术紧密结合,相互渗透,必将推进信息技术及相关的高新技术进入新的发展阶段。本书共分为9章,从技术基础和实际应用的角度出发,着重对微电子与光电子集成技术相关的工艺基础、基本原理和关键集成技术进行了详细阐述,主要内容包括光发射器件、光电探测器、光波导器件、光电子专用集成电路、硅基光电子集成回路、甚短距离光传输技术以及微电子与光电子混合集成技术等。 微电子与光电子集成技术的实用化进程,必将为21世纪科学技术的发展作出重大贡献。然而,微电子与光电子集成技术是信息技术发展的一个崭新方向,虽然各项关键技术的发展取得了一定的进步,但还存在诸多难题需要进一步解决和完善。 本书主要为从事集成光电子和光通信等相关技术研究的科研人员提供参考。
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We present a new generation 980 nm submarine pump module that consists of a hermitically sealed 8-pin ceramic MiniDIL package without thermo-electric cooler.
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The in-situ p-type doping of 4H-SiC grown on off-oriented (0001) 4H-SiC substrates was performed with trimethylaluminum (TMA) and/or diborane (B2H6) as the dopants. The incorporations of Al and B atoms and their memory effects and the electrical properties of p-type 4H-SiC epilayers were characterized by secondary ion mass spectroscopy (SIMS) and Hall effect measurements, respectively. Both Al- and B-doped 4H-SiC epilayers were p-type conduction. It was shown that the profiles of the incorporated boron and aluminum concentration were in agreement with the designed TMA and B2H6 flow rate diagrams. The maximum hole concentration for the Al doped 4H-SiC was 3.52x10(20) cm(-3) with Hall mobility of about 1 cm(2)/Vs and resistivity of 1.6 similar to 2.2x10(-2) Omega cm. The heavily boron-doped 4H-SiC samples were also obtained with B2H6 gas flow rate of 5 sccm, yielding values of 0.328 Omega cm for resistivity, 5.3x10(18) cm(-3) for hole carrier concentration, and 7 cm(2)/VS for hole mobility. The doping efficiency of Al in SiC is larger than that of B. The memory effects of Al and B were investigated in undoped 4H-SiC by using SIMS measurement after a few run of doped 4H-SiC growth. It was clearly shown that the memory effect of Al is stronger than that of B. It is suggested that p-type 4H-SiC growth should be carried out in a separate reactor, especially for Al doping, in order to avoid the join contamination on the subsequent n-type growth. 4H-SiC PiN diodes were fabricated by using heavily B doped epilayers. Preliminary results of PiN diodes with blocking voltage of 300 V and forward voltage drop of 3.0 V were obtained.
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A new 12 channels parallel optical transmitter module in which a Vertical Cavity Surface Emitting Laser (VCSEL) has been selected as the optical source is capable of transmitting 37.5Gbps date over hundreds meters. A new 12 channels parallel optical receiver module in which a GaAs PIN (p-intrinsic-n-type) array has been selected as the optical receiver unit is capable of responding to 30Gbps date. A transmission system based on a 12 channels parallel optical transmitter module and a 12 channels parallel optical receiver module can be used as a 10Gbps STM-64 or an OC-192 optical transponder. The parallel optical modules and the parallel optical transmission system have passed the test in laboratory.
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This paper describes the design and fabrication process of a two-dimensional GaAs-based photonic crystal nanocavity and analyzes the optical characterization of cavity modes at room temperature. Single InAs/InGaAs quantum dots (QDs) layer was embedded in a GaAs waveguide layer grown on an Al0.7Ga0.3As layer and GaAs substrate. The patterning of the structure and the membrane release were achieved by using electron-beam lithography, reaction ion etching, inductively coupled plasma etching and selective wet etching. The micro-luminescence spectrum is recorded from the fabricated nanocavities, and it is found that some high-order cavity modes are clearly observed besides the lowest-order resonant mode is exhibited in spite of much high rate of nonradiative recombination. The variance of resonant modes is also discussed as a function of r/a ratio and will be used in techniques aimed to improve the probability of achieving spectral coupling of a single QD to a cavity mode.
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随着微电子器件复杂度的提高,空间辐射对于计算机程序的正确性影响正越来越明显。一般情况下,这些影响并不是永久的,而是瞬时故障。无论是太空中的信息处理系统、嵌入式实时控制系统,还是计算机集群、高性能超级计算机都可能由于错误的输出而导致灾难性的后果。 传统的可靠性系统采用抗辐射部件和冗余的硬件来达到可靠性的要求,但是其价格昂贵,性能落后于今天的商用部件(COTS)。针对COTS在容错能力上存在的不足,软件容错技术可以在不改变硬件结构的情况下,有效的提高计算机系统的可靠性。 瞬时故障在软件层面上主要表现为控制流错误和数据流错误,本文主要针对控制流错误进行容错处理。软件实现的控制流容错技术通过在编译时加入冗余的容错逻辑,在程序执行时进行控制流错误的检测和处理。 如何在保证容错能力的同时,尽量降低冗余逻辑所带来的系统开销,是控制流容错需要解决的主要问题。本文从控制流错误的基本概念,容错单元的选择,签名信息的建立,签名点和检测点的插入位置几个角度对控制流容错进行研究,主要内容有: 1.对常见的控制流容错方法进行了分析比较,对其优点和不足予以说明。 2.对控制流错误进行了分类,以此为基础,提出了基于相关前驱基本块的控制流容错方法(CFCLRB)。 3.提出了一种签名流模型,提出了基于签名流模型的控制流容错方法(CFCSF)。该方法能够对基本块间控制流错误进行检测,具有较低的时间开销、空间开销和较高的错误覆盖率。同时,该方法可以根据容错尺度的要求,灵活的插入和删除签名点与检测点,具有极强的扩展性。该方法还可以应对动态函数指针这种编译时难以确定的控制流情况。 4.基于汇编指令对上述方法予以实现,并实现了国际上常用的控制流容错方法Control Flow Checking by Software Signatures(CFCSS)和Control-flow Error Detection through Assertions(CEDA)做为对比。通过加入冗余的指令逻辑,完成了对原程序的容错功能。 5.基于PIN具实现了对控制流错误的注入,在相同的实验环境下对CFCLRB ,CFCSF,CFCSS,CEDA进行了对比实验。实验表明, CFCLRB的时间开销为26.9%,空间开销为27.6%,相比不具容错能力的原程序,其错误覆盖率从66.50%提升到97.32%。CFCSF的时间开销为14.7%,空间开销为22.1%,相比不具容错能力的原程序,其错误覆盖率从66.50%提升到96.79%。相比CFCSS,该方法的时间开销从37.2%下降到14.7%,空间开销从31.2%下降到22.1%,错误覆盖率从95.16%提升到96.79%。相比CEDA,该方法的时间开销从26.9%下降到14.7%,空间开销从27.1%下降到22.1%,错误覆盖率仅从97.39%下降到96.79%。 最后,本文对控制流容错的未来研究方向进行了展望。
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Bacteriorhodopsin (BR) films oriented by an electrophoretic method are deposited on a transparent conductive ITO glass. A counterelectrode of copper and gelose gel is used to compose a sandwich-type photodetector with the structure of ITO/BR film/gelose gel/Cu. A single 30-ps laser pulse and a mode-locked pulse train are respectively used to excite the BR photodetector. The ultrafast failing edge and the bipolar response signal are measured by the digital oscilloscope under seven different time ranges. Marquardt nonlinear least squares fitting is used to fit all the experimental data and a good fitting equation is found to describe the kinetic process of the photoelectric signal. Data fitting resolves six exponential components that can be assigned to a seven-step BR photocycle model: BR-->K-->KL-->L-->M-->N-->O-->BR. Comparing tests of the BR photodetector with a 100-ps Si PIN photodiode demonstrates that this type of BIR photocletector has at least 100-ps response time and can also serve as a fast photoelectric switch. (C) 2003 Society of Photo-Optical Instrumentation Engineers.
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A kind of microstructured polymer optical fiber with elliptical core has been fabricated by adopting in-situ chemical polymerization technology and the secondary sleeving draw-stretching technique. Microscope photography demonstrates the clear hole-structure retained in the fiber. Though the holes distortion is visible, initial laser experiment indicates that light can be strongly confined in the elliptical core region, and the mode field is split obviously and presents the multi-mode characteristic. Numerical modeling is carried out for the real fiber with the measured parameters, including the external diameter of 150 pin, the average holes diameter of 3.3 mu m, and the average hole spacing of 6.3 mu m. by using full-vector plane wave method. The guided mode fields of the numerical simulation are consistent with the experiment result. This fiber shows the strong multi-mode and weak birefringence in the visible and near-infrared band, and has possibility for achieving the fiber mode convertors, mode selective couplers and so on.
OPTICAL BISTABILITY IN A GAAS/GAALAS MULTI-QUANTUM-WELL (MQW) SELF-ELECTROOPTIC EFFECT DEVICE (SEED)
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Based on a GaAs/GaAlAs MQW pin structure grown by a home-made MBE system, we have successfully fabricated a SEED. The optical bistability and related properties of the device under symmetric operation (S-SEED) and asymmetric operation are reported.
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A GaAs/GaAlAs graded-index separate confinement single quantum well heterostructure single-mode ridge waveguide electroabsorption modulator was fabricated and investigated. For the modulator with a quantum well width of 100 angstrom and device length of 700-mu-m, an on/off ratio of 29.7 dB and estimated absorption insertion loss of 3 dB were obtained for TE polarised light with wavelength 8650 angstrom, and for TM polarisation the on/off ratio was 28.5 dB. With a switching voltage of 1 V, an on/off ratio of 15 dB was achieved. Photocurrent spectra exhibited a red shift of 600 angstrom of the absorption edge when the voltage applied to the PIN diode was varied from 0.5 to -7 V. The corresponding shift of the room temperature exciton peak energy was 96 meV.
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研究了STM-64数据帧的转换映射技术,利用垂直腔面发射激光器(VCSEL)列阵光源和PIN阵探测器成功研制出10 Gb/s的甚短距离12信道SDH并行光传输系统,该系统结构紧凑,具有检错和纠错功能。跟传统的10 Gb/s串行光传输系统相比,本系统降低了对单路器件传输性能的要求。经SDH传输测试仪测试,系统能实现无误传输。