Modeling of a Back-Illuminated HgCdTe MWIR Avalanche Photodiode with Alloy Gradients

19th International Conference on Electron Dynamics in Semiconductors, Optoelectronics and Nanostructures

Storebø, A.K.^1 ; Brudevoll, T.^1

Norwegian Defence Research Establishment, PO Box 25, Kjeller

2007, Norway^1

关键词: Back-illuminated;    Excess noise factor;    Excitation position;    Gradient electric fields;    Gradient fields;    Mid wave infrared (MWIR);    Multiplication gain;    Naturally occurring;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/647/1/012051/pdf
DOI  :  10.1088/1742-6596/647/1/012051

来源: IOP

【 摘 要 】

We present results from 2D Monte Carlo simulations of a mid-wave infrared (MWIR) back-illuminated planar n-on-p HgCdTe electron-initiated avalanche photodiode (e- APD). The main objective of this work has been to study the dependence of the multiplication gain, excess noise factor, and response time on the position where the incident photon is absorbed. We also quantify the effects of the naturally occurring vertical alloy gradient electric fields in APDs grown by liquid phase epitaxy. The simulated gain is relatively independent of the excitation position, but a small increase is observed near the edges of the APD. The excess noise factor is around 1.2 for all positions. It is found that the alloy gradient field helps to speed up the response of the device, especially for excitation positions far away from the multiplication region.