非晶态半导体的现状与展望

本文将使搬地介绍了非晶态半导体的发展悄况，阐述了当前非晶态半导体的前沿课题以及器件应用情况，井预期非晶态半导体将有较大的发展．     

非晶硅半导体及其在传感技术中的应用

叙述了非晶硅半导体的结构、制备方法及特性，介绍了非晶硅在制作光电传感器、色敏传咸器、放射线（Ｘ射线等）传感器及应变传感器等方面的应用。并介绍了这些传感器的大致结构、输出特性及有关的应用．     

用于Rb原子冷却系统的半导体激光放大(TPA)装置

报道了我们最近研制的780 13m半导体激光放大装置.激光放大管采用Eagleyard公司生产的(EYP-TPA-0780-01000)半导体锥形放大器,当输入的种子源激光功率为25 mW时,放大器输出的激光功率达600mW左右,该光束经过透镜整形,声光调制器频移,然后耦合到单模保偏光纤后,输出功率达110 mW.该激光放大装置可很好的用于高密度冷原子的俘获.     

Transition of the True Ground State in a Coupled Three—Layer Quantum Dot

Low-lying states of a vertically coupled three-layer quantum-dot system are studied.Each layer contains one electron,and the tunnelling of electrons between layers is neglected.Effects of the interlayer separation d and the external magnetic field B are evaluated by numerical calculations.In the strong coupling case (i.e.d is small),as in a single dot,transitions of the angular momentum L of the true ground states occur when B increases, whereas in the weak coupling case the transition does not occur and L remains zero.Furthermore,it is found that the variation of d may also induce the L transition.As a result,a phase diagram of L of the true ground state is given in the d-B plane.     

Na/Si(111)3×1表面的NEXAFS研究

利用同步辐射光源测量Na2s二次电子部分产额谱得到Na诱导Si（111）3×1结构的近边Ｘ射线吸收精细结构（NEXAFS）谱，并用原子集团多重散射方法对几种可能的模型进行计算，与实验结果比较，认为Na/Si（111）3×1吸附结构与Mnch模型相一致．Na原子吸附在Si的顶位，Na—Si键长为0.3nm． 关键词：     

Role of Interactions in Electronic Structure of a Two-Electron Quantum Dot Molecule

We have studied a two-electron quantum dot molecule in a magnetic field. The electron interaction is treated accurately by the direct diagonalization of the Hamiltonian matrix. We calculate two lowest energy levels of the two-electron quantum dot molecule in a magnetic field. Our results show that the electron interactions are significant, as they can change the total spin of the two-electron ground state of the system by adjusting the magnetic field between S = 0 and S = 1. The energy difference AE between the lowest S = 0 and S = 1 states is shown as a function of the axial magnetic field. We found that the energy difference between the lowest S = 0 and S = 1 states in the strong-B S = 0 state varies linearly. Our results provide a possible realization for a qubit to be fabricated by current growth techniques.     

半导体材料科学发展的历史回顾

半导体科学技术是２０世纪中最伟大和最重要的科技成就之一。在高新技术迅速发展的今天，重温其发展历程，总结其发展规律和认识其发展特点，具有重要的现实意义。作者着重评述了近半个世纪以来，半导体科学技术在材料、物理、器件与工艺四个领域内所取得的一系列重大进展。     

高功率微波作用下金属氧化物半导体场效应管响应

采用基于半导体漂移扩散模型的数值模拟软件对高功率微波(HPM)作用下金属氧化物半导体场效应管(MOSFET)的响应进行了数值模拟研究。对MOSFET在HPM作用下的输出特性以及器件内部响应进行了数值模拟。计算结果表明,在MOSFET栅极加载HPM后,随着注入HPM幅值的增大,会使得器件的正向电压小于开启电压,从而使得输出电流的波形发生形变。在器件内部,导电沟道靠近源极一端的电场强度最大,热量产生集中在这一区域。在脉冲正半周期时,温度峰值位于沟道源极一端,负半周期时,器件内部几乎没有电流,器件内的温度峰值在热扩散效应的影响下趋向于导电沟道中部。     

非晶半导体基本理论及目前发展概况

 一、非晶半导体基本理论非晶态半导体是一门发展极为迅速的新兴学科,是凝聚态物理学中最为活跃的领域之一,已成为材料学科的一个组成部分.大量的事实说明,研究非晶态半导体的意义不仅在技术上能够产生新材料和新器件,而且对于认识固体理论中的许多基本问题也会产生深远的影响.晶态半导体的基本特征是:组成它的原子或分子作周期性排列,叫作长程有序性.基于这样的特征,利用能带理论,使得晶态半导体中的许多物理问题和半导体器件的基本原理得到了比较满意的解决.而非晶态半导体,结构上是一种共价网络,没有周期性排列的约束,所以它在结构上、光学电学性质上很不同于晶态半导体.因此,在应用上也显示了自己的特征,已呈现了巨大的应用前景.     

Dynamic Localization of a One—Dimensional Quantum Dot Array in an ac Electric Field

We investigate the dynamics of two interaction electrons confined to one-dimensional quantum dot array in an ac electric field.We find that initially localized electrons will remain localized in the absence of coulomb interaction if the ratio of the ac field magnitude to the frequency is a root of the ordinary zero-order Bessel function.In contrast to the case without Coulomb interaction,no matter what the value is,the electrons are delocalized and the delocalization effect depends on the ratio U/ω and eaE/ω,where U is the strength of Coulomb interaction,a is the lattice constant,and E and ω are the ac field amplitude and frequency,respectively.     

稀释磁性半导体

稀释磁性半导体是指Ⅱ－Ⅵ族、Ⅳ－Ⅵ族、Ⅱ－Ⅴ族或Ⅲ－Ⅴ族化合物中，由磁性过渡族金属离子或稀土金属离子部分地替代非磁性阳离子所形成的新的一类半导体材料。这类材料的突出特点是磁性离子磁矩和能带电子自旋之间存在交换相互作用。由此引起材料性质发生一系列重要变化。本文系统介绍这类材料的各种物理性质，包括能带结构，ｓｐ－ｄ和ｄ－ｄ交换作用，磁性质和自旋玻璃特性，光学和磁学性质，输运特性等。最后简单介绍这类材料     

极性／非极性半导体异质结构

由极性半导体ＧａＡｓ，ＧａＰ 等和非极性半导体Ｇｅ，Ｓｉ等构成的异质结构，为高速集成和光电子集成技术的发展提供了新的机会，同时也为基础物理研究提出了新的课题．本文简要介绍极性／非极性半导体异质结构的制备和特性方面的一些基本问题及其在器件应用方面的发展现状．     

甲壳胺膜中MS(M=Cd,Zn)半导体纳米微粒形成机理的探讨

采用红外光谱（ＩＲ）和原子力显微镜（ＡＦＭ）对甲壳胺中纳米微晶生长过程进行了监测,并对测试结果进行了分析与讨论,提出甲壳胺膜中ＭＳ（Ｍ＝Ｃｄ,Ｚｎ）半导体纳米微晶可能的生长机制。同时还利用ＡＦＭ对甲壳胺中纳米微晶的形貌和尺度进行了测定。     

我国半导体物理研究进展

简单地回顾了近年来我国半导体物理研究的进展,它包括三个方面,半导体超晶格、微结构;半导体表面、界面和杂质、缺陷;以及半导体新材料、新结构,这些进展说明,半导体物理研究在当代物理学和高技术的发展中都占有突出的地位,它仍是一门年轻的、富有生命力的学科,预期在将来有更大的发展。     

GaN基半导体新热点:从半导体照明到功率电子器件

Ⅲ族氮化物(又称GaN基)宽禁带半导体属于新兴的第三代半导体体系,在短波长光电子器件和功率电子器件领域具有重大应用价值。过去10多年,以蓝光和白光LED为核心的半导体照明技术和产业飞速发展,形成了对国家经济和人民生活产生显著影响的高技术产业。近年来GaN基功率电子器件受到了学术界和产业界的高度重视,形成了新的研发和产业化热点。首先介绍了半导体照明技术和产业的发展历程和现状,分析了当前GaN基LED芯片技术面临的关键科学和技术问题;然后重点介绍了GaN基微波功率器件和电力电子器件的发展历程和动态,包括微波功率器件已经取得的突破性进展和产业化现状,电力电子器件相对Si和SiC同类器件的优势和劣势,并对GaN基功率电子器件当前面临的关键科学和技术挑战进行了较详细的分析。     

Investigation of the characteristics of GIDL current in 90nm CMOS technology

A specially designed experiment is performed for investigating gate-induced drain leakage (GIDL) current in 90nm CMOS technology using lightly-doped drain (LDD) NMOSFET. This paper shows that the drain bias $V_{\rm D}$ has a strong effect on GIDL current as compared with the gate bias $V_{\rm G}$ at the same drain--gate voltage $V_{\rm DG}$. It is found that the difference between $I_{\rm D}$ in the off-state $I_{\rm D}-V_{\rm G}$ characteristics and the corresponding one in the off-state $I_{\rm D}-V_{\rm D}$ characteristics, which is defined as $I_{\rm DIFF}$, versus $V_{\rm DG}$ shows a peak. The difference between the influences of $V_{\rm D}$ and $V_{\rm G}$ on GIDL current is shown quantitatively by $I_{\rm DIFF}$, especially in 90nm scale. The difference is due to different hole tunnellings. Furthermore, the maximum $I_{\rm DIFF }$($I_{\rm DIFF,MAX})$ varies linearly with $V_{\rm DG}$ in logarithmic coordinates and also $V_{\rm DG}$ at $I_{\rm DIFF,MAX}$ with $V_{\rm F}$ which is the characteristic voltage of $I_{\rm DIFF}$. The relations are studied and some related expressions are given.     

窄台衬底内条形半导体激光器

研制了一种新型结构双异质结半导体激光器,这种激光器是利用非平面衬底液相外延的特点,使电流阻挡层和四层双异质结构在腐蚀成窄台的衬底上一次外延完成生长,内条形电流通路在外延生长中自然形成.工艺特别简单,且具有良好线性输出和稳定基横模式振荡等特点.     

利用霍尔效应区分P型与N型半导体的理论诠释

从理论上对利用霍尔效应区分产型与Ｎ型半导体作出了诠释．     

Power dissipation characteristics of great power and super high speed semiconductor switch

The power dissipation characteristics of pulsed power switch reversely switched dynistors （RSDs） are investigated in this paper. According to the expressions of voltage on RSD, derived from the plasma bipolar drift model and the RLC circuit equations of RSD main loop, the simulation waveforms of current and voltage on RSD are acquired through iterative calculation by using the fourth order Runge-Kutta method, then the curve of transient power on RSD versus time is obtained. The result shows that the total dissipation on RSD is trivial compared with the pulse discharge energy and the commutation dissipation can be nearly ignored compared with the quasi-static dissipation. These characteristics can make the repetitive frequency of RSD increase largely. The experimental results prove the validity of simulation calculations. The influence factors on power dissipation are discussed. The power dissipation increases with the increase of the peak current and the n-base width and with the decrease of n-base doping concentration. In order to keep a low power dissipation, it is suggested that the n-base width should be smaller than 320μm when doping concentration is 1.0×10^14cm^-3 while the doping concentration should be higher than 5.8×10^13cm^-3 when n-base width is 270μm.     

基于FPGA的半导体激光器温度控制系统设计

介绍了半导体激光器的温度控制原理,设计了基于FPGA的半导体激光器温度控制系统。系统采用数字温度传感器DS18820作为温度测量器件,TEC作为控温执行元件,并采用模糊控制算法、PWM机制来控制TEC的驱动电流从而实现温控。基于QuartusⅡ开发平台采用Verilog HDL设计了软件部分,最后进行了功能仿真。整个系统对硬件要求不高,实现简单。从仿真结果可以看出,控制系统能够满足半导体激光器温度控制的精度和稳定度的要求。