基于异质结倍增层的InAlAsSb SACM雪崩光电二极管的优化

Optimization of InAlAsSb SACM APD with a heterojunction multiplication layer

使用低工作电压的雪崩光电二极管(APD)有利于提高集成电路的稳定性和降低功耗.文章建立了一个分离吸收、电荷、倍增(SACM)型的雪崩光电二极管的模型,为了在低偏压下获得高增益同时不降低工作电压范围,这个模型采用了具有高低禁带宽度的异质结倍增层.同时,文章研究了异质结倍增层的厚度和掺杂浓度对暗电流和增益的影响.通过对掺杂浓度的优化,击穿电压和穿通电压可以同时下降.

For avalanche photodiodes (APDs), low operation voltage is required for integrated circuit stability and low power consumption. In this paper, a model for InAlAsSb separate absorption, charge, and multiplication (SACM) APD is established. To get higher gain at lower reversed bias voltage without sacrificing the operating voltage range, a high/low band gap multiplication layer is adopted. The effects of the thickness and doping concentration of the multiplication layer on the dark-current and the break-down voltage have been investigated. By optimization of the doping concentration, the break-down voltage and punch-through voltage can be decreased simultaneously.