转移电子光阴极调制传递函数的理论计算

本文利用蒙特卡罗模拟的方法计算了Ａｇ／ｐ－ＩｎＰ／ｐ－ＩｎＡｇＡｓＰ／ＩｎＰ转移电子光阴极的调制传递函数，计算结果表明转移电子光阴极具有较高的空间分辨率，并与阴极材料的吸收系数，有源层厚度有场助偏压有关，为获得较高的调制传递函数，应当昼降低吸收系数和缩短有源层厚度，提高场助电压。     

非故意掺杂吸收层InP/InGaAs异质结探测器研究

为了获得低噪声铟镓砷（InGaAs）焦平面,需要采用高质量的非故意掺杂InGaAs（u-InGaAs）吸收层进行探测器的制备。采用闭管扩散方式,实现了Zn元素在u-InGaAs吸收层晶格匹配InP/In_0.53Ga_0.47As异质结构材料中的P型掺杂,利用扫描电容显微技术(SCM)对Zn在材料中的扩散过程进行了研究,结果表明,随着扩散温度和时间增加,p-n结结深显著增加,u-InGaAs吸收层材料的扩散界面相比较高吸收层浓度材料（5×1016 cm?3）趋于缓变。根据实验结果计算了530 ℃下Zn在InP中的扩散系数为1.27×10?12 cm2/s。采用微波光电导衰退法(μ-PCD)提取了InGaAs吸收层的少子寿命为5.2 μs。采用激光诱导电流技术(LBIC)研究了室温下u-InGaAs吸收层器件的光响应分布,结果表明:有效光敏面积显著增大,对实验数据的拟合求出了少子扩散长度L_D为63 μm,与理论计算基本一致。采用u-InGaAs吸收层研制的器件在室温(296 K)下暗电流密度为7.9 nA/cm2,变温测试得到激活能E_a为0.66 eV,通过拟合器件的暗电流成分,得到器件的吸收层少子寿命τ_p约为5.11 μs,与微波光电导衰退法测得的少子寿命基本一致。     

近红外响应的III-V族半导体光电阴极材料及工艺

随着GaAs负电子亲和势(NEA)半导体光电阴极在我国的成熟和应用,半导体光电阴极的进一步研究将往更长波的近红外发展。针对透射式半导体光电阴极器件,系统总结了近红外波段响应良好的GaAs、InGaAs、InGaAsP Ⅲ-V族外延材料特性及相应商业化产品的应用领域和性能。通过文献调研本文进一步归纳了不同波段NEA光电阴极和转移电子光阴极适用的材料结构,并结合传统GaAs NEA光电阴极工艺讨论了InGaAs、InGaAsP材料及阴极工艺的难点。     

InGaAs／InP短时间液相外延层厚度与生长时间的数学拟合

在液相外延（ＬＰＥ）工艺中，采用常规的过冷降温技术，在６４０℃下进行短时间的液相外延ＩｎＧａＡｓ／ＩｎＰ的生长实验，用扫描电镜测量不同生长时间下的外延层厚，对实验曲线进行数学拟合，得到ｄ＝０．２＋０．１３２ｔ０．７５７５的短时间生长厚度与时间的表达式．结果表明，短时间ＬＰＥ生长ＩｎＧａＡｓ／ＩｎＰ和ＩｎＧａＡｓ／ＧａＡｓ相类似，有着相同的初始快速生长阶段．     

近红外响应的Ⅲ-V族半导体光电阴极材料及工艺北大核心

随着GaAs负电子亲和势(NEA)半导体光电阴极在我国的成熟和应用,半导体光电阴极的进一步研究将往更长波的近红外发展。针对透射式半导体光电阴极器件,系统总结了近红外波段响应良好的GaAs、InGaAs、InGaAsP Ⅲ-V族外延材料特性及相应商业化产品的应用领域和性能。通过文献调研本文进一步归纳了不同波段NEA光电阴极和转移电子光阴极适用的材料结构,并结合传统GaAs NEA光电阴极工艺讨论了InGaAs、InGaAsP材料及阴极工艺的难点。     

基于InP/InGaAs HBT技术的单片集成长波长光接收OEIC

采用InP/InGaAs HBT与PIN光探测器单片集成方案,对光接收光电集成电路(OEIC)的外延材料结构和生长、电路设计、制作工艺和性能测试进行了研究.基于自对准InP/InGaAs HBT工艺,实现了1.55μm波长单片集成光接收OEIC.发射极尺寸2μm×8μm的InP/InGaAs HBT直流增益为40,截止频率和最高振荡频率分别为45和54GHz;集成InGaAs PIN光探测器在-5V下响应度为0.45A/W@1.55/μm,暗电流小于10nA,-3dB带宽达到10.6GHz;研制的HBT/PIN单片集成光接收OEIC在2.5和3.0Gb/s速率非归零223-1伪随机码传输工作时可以观察到张开的眼图,灵敏度≤-15.2dBm@BER=10-9.     

基于InP/InGaAs HBT技术的单片集成长波长光接收OEIC

采用InP/InGaAs HBT与PIN光探测器单片集成方案,对光接收光电集成电路(OEIC)的外延材料结构和生长、电路设计、制作工艺和性能测试进行了研究.基于自对准InP/InGaAs HBT工艺,实现了1.55μm波长单片集成光接收OEIC.发射极尺寸2μm×8μm的InP/InGaAs HBT直流增益为40,截止频率和最高振荡频率分别为45和54GHz;集成InGaAs PIN光探测器在-5V下响应度为0.45A/W@1.55/μm,暗电流小于10nA,-3dB带宽达到10.6GHz;研制的HBT/PIN单片集成光接收OEIC在2.5和3.0Gb/s速率非归零223-1伪随机码传输工作时可以观察到张开的眼图,灵敏度≤-15.2dBm@BER=10-9.     

单片集成InGaAs PIN-JFET光接收器的设计与研制

本文报告了一种OEIC器件:单片集成InGaAs PIN-JFET光接收器的设计与研制结果.为解决光电器件与电子器件在集成上的兼容性,采用了在结构衬底上进行平面化外延的新工艺,达到了器件的准平面结构,并对器件的主要参数进行了计算,选取了较佳的载流子浓度.制成的单片集成器件中,PIN光探测器的量子效率在1.3μm处为57％,暗电流在-5V下小于100nA,JFET的跨导为34ms/mm,与计算植相符.对器件进行光接收功能测试获得了预期的结果.     

InP/InGaAs/InP红外光电阴极时间响应特性的模拟研究

文中理论研究了InP/In0.53Ga0.47As/InP异质结透射式红外光电阴极的时间响应特性,光谱响应范围1.0～1.7 m。在场助偏压的作用下,模拟计算了光激发的电子在阴极内部的传输特性。模拟计算表明,光电阴极的响应速度随场助偏压的增大而加快;随光吸收层厚度的增大而减慢;随光吸收层掺杂浓度的增大,光电阴极的响应速度变慢。发射层厚度及掺杂浓度的增大都会使得阴极的响应时间加长。经过对阴极结构参数和掺杂浓度的优化,得到在吸收层和发射层厚度分别为2 m、0.5 m,掺杂浓度分别为1.51015 cm-3、1.01016 cm-3时,在适当场助偏压下光电阴极的响应时间可优于100 ps。     

一种InGaAs/InP复合沟道高电子迁移率晶体管模拟的新方法

采用一种新方法对InGaAs/InP复合沟道高电子迁移率晶体管进行了模拟.该方法通过流体力学模型和密度梯度模型的联合求解,得到了沟道内的电子密度分布.与一些传统方法相比,该方法收敛性更好,速度更快,且同样适用于其他类型高电子迁移率晶体管器件的模拟.利用仿真对InGaAs/InP复合沟道高电子迁移率晶体管进行了深入研究.     

Optimization of the spacer layer thickness in AlInAs/InGaAs/InP MODFETs

The effects of spacer layer thickness variations on single atomic planar doped (APD) AlInAs/InGaAs modulation doped field effect transistors grown by solid source molecular beam epitaxy have been studied and characterized. The thickness of the AlInAs spacer layer was varied between 0 and 100Å. Room temperature Hall measurements found the mobility exhibited an exponential relationship ranging from 6500 to 10800 cm²/Vs. The sheet charge varied linearly from 3.46 × 10¹² cm^?2 to 2.24 × 10¹² cm^?2. An optimum spacer layer thickness based on maximum channel conductance was found to be 40Å with a mobility of 9600 cm²/Vs and a sheet charge of 3.0 × 10¹² cm^?2. The loss of mobility due to remote ion scattering was examined. This loss was related to the distribution of the Si atoms in the atomic planar doped layer in order to obtain the standard deviation of the interface. This relationship will allow various growth parameters, such as substrate temperature, growth rate, and V/III ratio to be altered to determine the optimum conditions independent of the growth chamber used to create the structures.     

InGaAs/InP单光子雪崩光电二极管InP顶层掺杂研究

通过理论计算和对比实验研究了InGaAs/InP单光子雪崩光电二极管中InP顶层掺杂浓度对于器件性能的影响.理论结果显示,InP顶层的掺杂浓度越低越有利于抑制边缘击穿,降低隧穿暗载流子产生速率,提高雪崩击穿几率.实验结果显示,顶层非故意掺杂的器件在223K下获得了20%的单光子探测效率和1kHz的暗计数率,其单光子探测效率比顶层掺杂浓度为5×10~(15)/cm~3的器件高3%~8%,而暗计数率低一个量级.结果表明,降低InP顶层的掺杂浓度有利于提高器件性能.     

Design and characteristics of InGaAs/InP composite-channel HFET's

A design for composite-channel structures consisting of an InGaAs channel and an InP subchannel for use as heterostructure field-effect transistors is presented for the first time. This novel channel structure takes advantage of both the high drift velocity and low impact ionization of InP at high electric fields as well as the high electron mobility of InGaAs at low electric fields. It is shown that the doping density of the InP subchannel is the key parameter to realize the advantages of the composite channel. A very high transconductance of 1.29 S/mm and a current gain cutoff frequency of 68.7 GHz are achieved with 0.6 and 0.7 /spl mu/m gates, respectively. The average velocity of electrons in the composite channel is 2.9/spl times/10/sup 7/ cm/s. The devices have no kink phenomena in their I-V characteristics possibly due to low impact ionization in the InP subchannel.<>     

High-speed InP/InGaAs avalanche photodiodes with a compositionallygraded quaternary layer

InP/InGaAs avalanche photodiodes (APDs) with a compositionally graded quaternary layer at the heterointerface between the InGaAs absorption and InP multiplication regions were fabricated and tested. A comparison of samples with the graded layer and with conventional three quaternary layers showed that the frequency characteristics for samples with the graded layer did not deteriorate at a low bias voltage even below -100°C, unlike APDs with three InGaAsP layers. Thus, no hole trapping occurred at the InP/InGaAs heterointerface with the graded layer. A sample with the graded layer showed a cutoff frequency exceeding 9 GHz at a low multiplication factor of 2. The authors found InP/InGaAs APDs with the compositionally graded quaternary layer to be useful over a wide temperature range     

New type InGaAs/InP heterostructure avalanche photodiode with buffer layer

A new type heterostructure avalanche photodiode (HAPD) is proposed and successfully fabricated by liquid phase epitaxy and Zn-diffusion. The HAPD has been made from a successively grown wafer which consists of In0.53Ga0.47As light absorption layer, InGaAsP buffer layers and InP avalanche multiplication layer on n-InP substrate. Dark current density of 1 × 10^-4Acm^-2at 0.9 VBis achieved. When illuminating with 1.15 µm light, the diode has a maximum multiplication gain of 880 and an external quantum efficiency of 40%. The quantum efficiency is markedly improved than that of previously reported HAPD.     

InP/InGaAs异质结双极晶体管研究

阐述了ＩｎＰ／ＩｎＧａＡｓ异质结双极晶体管的最新发展动态,重点讨论了ＨＢＴ的结构与性能以及ＨＢＴＩＣ的高速性能与可靠性问题     

InP/InGaAs SHBT器件自对准结构设计和工艺实现

从InP湿法腐蚀各向异性特性实验出发,利用传统的基极-发射极自对准工艺和改进的基极-发射极工艺制作了两种InP/InGaAs SHBT自对准结构,比较了两种自对准工艺对减小基极与发射极台面间距的效果,为制作高频率特性InP/InGaAs SHBT提供了工艺途径.     

InP/InGaAs SHBT器件自对准结构设计和工艺实现

从InP湿法腐蚀各向异性特性实验出发，利用传统的基极-发射极自对准工艺和改进的基极-发射极工艺制作了两种InP/InGaAs SHBT自对准结构，比较了两种自对准工艺对减小基极与发射极台面间距的效果，为制作高频率特性InP/InGaAs SHBT提供了工艺途径.