半导体量子器件物理讲座-第七讲 半导体异质结光电探测器

光电探测器是一类用于接收光波并转变为电信号的专门器件。文章描述了PIN光电二极管、雪崩光电二极管、MSM（金属-半导体-金属）光电二极管的器件结构和工作原理，并对它们的响应度、噪声、带宽等特性进行了讨论。这类器件已在光通信、光信息处理等许多系统中得到广泛的应用。

一种新型SOI Mach-Zehnder干涉型电光调制器的设计

在超紧缩双曲锥形3 dB多模干涉耦合器的基础上，设计了一种新的Silicon-on-insulator (SOI) Mach-Zehnder干涉型电光调制器。与传统的Y分支器相比，双曲锥形3 dB耦合器的制作容差大，而长度缩短了近30％，使得整个器件的尺寸大幅减小。调制区采用横向注入的PIN结构，模拟结果表明

镜面起伏对1.55 μm Si基MEMS光滤波器的影响

用传输矩阵方法，在简化的光学模型基础上，分别讨论了分布式Bragg反射镜DBR（Distributed Bragg Reflector）的生长精度及镜面起伏对1.55 μm Si基MEMS（Micro-Electro-Mechanical-System）可调谐光滤波器透射谱的影响。计算表明

双折射对基于半导体光放大器的干涉型器件性能影响的模拟分析研究

分析了半导体光放大器中双折射对基于半导体光放大器的干涉型器件性能的影响，对基于半导体光放大器的马赫－曾德尔型波长转换器的理论计算表明，当半导体光放大器有双折射存在时，消光比不仅要比无双折射的要低，而且还随着探测光的偏振态而改变，变化幅度可大于10 dB。提出了减小双折射对干涉型器件影响的方案，并且分析了实现对增益和对相位变化同时具有偏振不灵敏的半导体光放大器的可能性。

SOI梯形截面光波导的模式分析

采用有效折射率和转移矩阵理论相结合的方法得到了SOI梯形光波导的本征模方程。计算得到的有效折射率与WKB法相比误差不超过10~(-5)，其垂直方向电场分布与BPM模拟结果基本相符。首次得到了SOI梯形波导的单模曲线和其近似解析表达式，此结果与修正的WKB法一致。

一种具有平顶陡边响应的新型谐振腔增强型（RCE）光电探测器的理论分析及模拟

提出了一种适用于波分复用系统的具有平顶陡边响应的新型谐振腔强型（RCE）光电探测器结构，模拟得到了量子效率从峰值下降0.5dB的线宽1.8 nm，10 dB的线宽5.6 nm，20 dB的线宽10.4 nm，量子效率峰值99.7%，几乎没有凹陷的响应曲线。

3μm GaInNAs/GasAs Quantum Well Resonant Cavity Enhanced Photodetector

A 1.3μm GaInNAs resonant cavity enhanced (RCE) photodetector (PD) has been grown by molecular beam epitaxy (MBE) monolithically on (100) GaAs substrate using a home-made ion-removed dc-plasma cell as nitrogen source. A transfer matrix method was used to optimize the device structure. The absorption region is composed of three GaInNAs quantum wells separated by GaAs layers. Devices were isolated by etching 130μm-diameter mesas and filling polyamide into grooves. The maximal quantum efficiency of the device is about 12% at 1.293μm. Full width at half maximum (FWHM) is 5.8nm and 3dB bandwidth is 304MHz. Dark current is 2 * 10~(-11) A at zero bias voltage. Further improvement of the performance of the RCE PD can be obtained by optimizing of the structure design and MBE growth conditions.

BPM方法在SOI结构中的应用

采用交错隐式算子分裂（ADI）算法，设计、实现了一种高速、高精度的波束传播方法（BPM）来模拟SOI波导中不同偏振态的光传输，研究了PML边界层的选取对虚传播计算基模和基模传播常数的影响，给出了大光腔SOI波导结构不同偏振的基模传播常数。

4 * 4区域调制多模干涉耦合器SOI光波导开关的设计

根据区域调制多模干涉耦合器光开关的工作原理，以2 * 2区域调制多模干涉光开关为基础，采用级联的方式设计了4 * 4区域调制多模干涉SOI光波导开关。用有限差分二维BPM方法模拟了器件在不同工作状态下的光场传输情况。器件工作波长为1.55 μm，在不计耦合损耗时器件的平均插入损耗小于2.0 dB/cm。

平顶陡边响应的谐振腔增强型（RCE）光电探测器的分析

报道了一种具有平顶陡边响应的谐振腔增强型（RCE）光电探测器。使用数值模拟的方法对这种新型谐振腔增强型（RCE）光电探测器与传统的RCE光电探测器的响应曲线和串扰特性进行了分析和对比，分析了在半导体材料生长时厚度偏差对平顶陡边响应的RCE光电探测器响应曲线的影响，还分析了入射光的入射角和偏振态对平顶陡边响应的RCE光电探测器响应曲线的影响。

In_(0.4)Ga_(0.6)As/GaAs自组织量子点的光伏谱温度特性

采用无需在样品上制备电极的电容耦合的光伏谱方法,实验测量了In_(0.4)Ga_(0.6)As/GaAs自组织量子点在不同的温度下的光伏谱,对测量谱峰进行了指认,研究了量子点谱峰能量位置随温度的依赖关系。实验结果表明,量子点具有与体材料及二维体系不同的温度特性,对实验所测样品,其激子峰能量随温度增加而红移的速率约为GaAs体材料带隙变化的1.4倍。

GaAs脊形量子线结构的MBE生长机理研究

报道了非平面衬底上分子束外延生长GaAs脊形量子线结构的实验研究。已成功地在GaAs(001)刻蚀条形衬底上生长出了由(111)面和(113)面构成的两种脊形量子线结构。讨论了非平面衬底上MBE生长脊形结构的形成机制,认为在一定的生长条件下,脊形结构的表面取向是由两个原始交界面上生长速率的相对差异决定的;而生长速率的差异是由表面再构的不同决定的。

Using photoluminescence as optimization criterion to achieve high-quality InGaAs/AlGaAs pHEMT structure

The single delta -doped InGaAs/AlGaAs pseudomorphic HEMT structure materials were grown by molecular beam epitaxy. The photoluminescence spectra of the materials were studied. There are two peaks in the photoluminescence spectra of the materials, corresponding to two sub energy levels of InGaAs quantum well. The ratio of the two peak's intensity was used as criterion to optimize the layer structures of the materials. The material with optimized layer ;tructures exhibits the 77 It mobility and two-dimensional electron gas density of 16 500 cm(2)/Vs and 2.58 x 10(12) cm(-2) respectively, and the 300 K mobility and two-dimensional electron gas density of 6800 cm(2)/Vs and 2.55 x 10(12) cm(-2) respectively. The pseudomorphic HEMT devices with gate length of 0.2 mum were fabricated using this material. The maximum transconductance of 650 mS/mm and the cut-off frequency of 81 GHz were achieved. (C) 2001 Elsevier Science B.V. All rights reserved.

High-quality metamorphic HEMT grown on GaAs substrates by MBE

Metamorphic high electron mobility transistor (M-HEMT) structures have been grown on GaAs substrates by molecular beam epitaxy (MBE). Linearly graded and the step-graded InGaAs and InAlAs buffet layers hal e been compared, and TEM, PL and low-temperature Hall have been used to analyze the properties of the buffer layers and the M-HEMT structure. For a single-delta-doped M-HEMT structure with an In0.53Ga0.47As channel layer and a 0.8 mum step-graded InAlAs buffer layer, room-temperature mobility of 9000 cm(2)/V s and a sheet electron density as high as 3.6 x 10(12)/cm(2) are obtained. These results are nearly equivalent to those obtained for the same structure grown on an InP substrate. A basic M-HEMT device with 1 mum gate was fabricated, and g(m) is larger than 400 mS/mm. (C) 2001 Elsevier Science B.V. All rights reserved.