雪崩光电探测器的击穿效应模型分析

Model Analysis of Breakdown Effects in Avalanche Photodetectors

基于CMOS工艺制备了空穴触发的Si基雪崩探测器(APD),基于不同工作温度下器件的击穿特性,建立空穴触发的雪崩器件的击穿效应模型。根据雪崩击穿模型和击穿电压测试结果,拟合曲线得到击穿电场与温度的关系参数(dE/dT),器件在250~320 K区间内,击穿电压与温度是正温度系数,器件发生雪崩击穿为主,dV/dT=23.3 mV/K,其值是由倍增区宽度以及载流子碰撞电离系数决定的。在50~140 K工作温度下,击穿电压是负温度系数,器件发生隧道击穿,dV/dT=-58.2 mV/K,其值主要受雪崩区电场的空间延伸和峰值电场两方面因素的影响。

In this paper,a hole-triggered Si avalanche detector(APD)was prepared based on CMOS process.And the breakdown effect model of the hole-triggered avalanche device was established based on the breakdown characteristics of the device at different operating temperatures.Based on the avalanche breakdown model and the breakdown voltage test results,the parameter of breakdown electric field versus temperature(dE/dT)was obtained by fitting the curve.The breakdown voltage and temperature are positive temperature coefficients at 250~320K.And the device undergoes avalanche breakdown dominated by dV/dT=23.3mV/K.The value is determined by the width of the multiplication region as well as the carrier collision ionization coefficient.At 50~140K operating temperature,the breakdown voltage is a negative temperature coefficient and the device undergoes tunnel breakdown with dV/dT=-58.2mV/K.The value is mainly influenced by both the spatial extension of the electric field in the avalanche region and the peak electric field.