雪崩光电二极管的边击穿抑制及过剩噪声因子测试

发布时间：2018-02-16 10:53

本文关键词： 雪崩光电二极管电场分布暗电流过剩噪声因子　出处：《华中科技大学》2015年硕士论文　论文类型：学位论文

【摘要】：雪崩光电二极管具有内部增益、高灵敏度等特性,目前在量子保密通信、国防、天文探测和其他光通信领域得到了越来越广泛的关注。雪崩光电二极管的应用发展受到噪声的影响,其主要来源是散粒噪声,散粒噪声对APD信噪比有很大的影响,而信噪比的主要影响因素是暗电流和APD特有的过剩噪声。本文分别对APD暗电流和过剩噪声特性进行了模拟仿真和实验测试研究,对高速低噪声APD的研制具有指导意义。首先,我们研究了APD电场分布对暗电流的影响。针对目前应用比较广泛的平面型InGaAs/InP APD存在的边缘提前击穿问题,我们通过COMSOL半导体模块仿真对已存在的一种抑制边缘提前击穿的方法即添加深保护环法进行了更深入的研究,研究了深保护环的深度、位置对APD暗电流的影响,发现在低偏压下深保护环的深度对APD的暗电流有一定的影响,但随着偏压增大差异逐渐减小,而改变深保护环与中央结的距离对APD的暗电流基本没有影响,并利用深保护环的优势将其应用到垂直入射平面型Si/Ge APD里,从而降低Ge吸收层的隧穿电流。其次,为了研究APD的过剩噪声特性,我们搭建了分别基于噪声分析仪和锁相放大器的两种测试系统,对同一APD进行噪声测试。我们通过实验数据对比分析了两种测试的方案存在的问题,研究了激光器引入的相对强度噪声对APD过剩噪声测试产生的影响,并提出了相应的测试处理方案。最后在此基础上我们提出了一种可以消除光源噪声的基于平衡探测的新的测试方案,从理论上对其存在的问题以及可行的解决方案进行了分析研究。
[Abstract]:Avalanche photodiodes with internal gain, high sensitivity and other characteristics, currently in quantum secure communications, defense, The application of avalanche photodiodes is affected by noise, the main source of which is shot noise, which has a great influence on the signal-to-noise ratio (SNR) of APD. The main influencing factors of signal-to-noise ratio are dark current and excess noise characteristic of APD. In this paper, the characteristics of dark current and excess noise of APD are simulated and tested respectively, which is of guiding significance to the development of high-speed low-noise APD. We study the influence of APD electric field distribution on dark current. Aiming at the edge breakdown problem of plane InGaAs/InP APD, which is widely used at present, Through the simulation of COMSOL semiconductor module, we have done more in-depth research on the existing method of restraining edge early breakdown, that is, adding deep protection loop, and studied the influence of the depth and position of deep protection ring on the dark current of APD. It is found that the depth of the deep protection ring has a certain effect on the dark current of APD at low bias voltage, but the difference decreases gradually with the increase of bias voltage, but changing the distance between the deep protection ring and the central junction has little effect on the dark current of APD. In order to reduce the tunneling current of GE absorption layer, the deep protection loop is applied to the vertical incident planar Si/Ge APD. Secondly, in order to study the excess noise characteristics of APD, Two kinds of test systems based on noise analyzer and phase-locked amplifier are built to test the noise of the same APD, and the problems of the two testing schemes are analyzed by comparing the experimental data. The influence of the relative intensity noise introduced by the laser on the measurement of APD excess noise is studied. Finally, we propose a new test scheme based on balanced detection, which can eliminate the noise of light source. The existing problems and feasible solutions are analyzed and studied theoretically.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN312.7

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