硅基锗PIN红外探测器的数值模拟研究  

Study of Si-based Ge PIN Infrared Detector with Numerical Simulation

作　　者：徐敏杰[1] 魏莹[1] 蔡雪原[1] 杨建红[1] 

机构地区：[1]兰州大学物理科学与技术学院微电子研究所,甘肃兰州730000

出　　处：《红外》2009年第11期35-39,共5页Infrared

摘　　要：本文基于漂移扩散模型,对硅基锗PIN红外探测器的电流特性随应变、Ge吸收层厚度、吸收层掺杂浓度的变化进行了数值模拟,并给出了一种器件优化设计方案。研究结果表明,当Ge应变从0增加到0.3%时,器件的暗电流增大了约50%;当Ge吸收层厚度从1μm增加到4μm时,器件的暗电流降低了近80%,量子效率增大了近1倍;当吸收层的掺杂浓度由1×10^(14)cm^(-3)增大2个量级时,器件的光电流降低了近60%。综合考虑吸收层厚度对器件量子效率和暗电流的影响以及吸收层掺杂浓度对光电流的影响,对硅基锗PIN红外探测器的外延锗吸收层进行了设计:外延生长厚度为4μm,掺杂浓度为1×10^(14)cm^(-3),以期能为提高器件性能和制备实际器件提供良好的依据。The variation of the current characteristics of a Si-based Ge PIN infrared detector with the strain, thickness and doping concentration of a Ge absorption layer is numerically simulated on the basis of a drift-diffusion model and an optimized device design scheme is given. The research result shows that when the tensile strain of the Ge absorption layer is increased from 0 to 0.3%, the dark current of the device is increased by about 50%; when the thickness of the Ge absorption layer is increased from 1μm to 4μm, the dark current of the device is decreased by about 80% and its quantum efficency is nearly doubled; and when the doping concentration of the Ge absorption layer is increased from 1 × 10^14cm-3 to 1×10^16cm-3, the dark current of the device is decreased by about 60%. In view of the effect of absorption layer thickness on the quantum efficiency and dark current of the device and the effect of doping concentration of the absorption layer on photocurrent, the Ge absorption layer of the Si-based Ge PIN infrared detector is designed to have a thickness of 4μm and a doping concentration of 1×10^14cm-3. It is expected that this design can provide a good basis for the improvement of device performance and the fabrication of practical devices.

关 键 词：红外探测器 PIN 硅锗 暗电流 应变 

分 类 号：TN215[电子电信—物理电子学]