Modeling Of Avalanche Multiplication And Excess Noise Factor In Ln_(0.52)al_(0.48) As Avalanche Photodiodes Using A Simple Monte Carlo Model

摘要

A simple Monte Carlo model has been, developed to simulate the avalanche multiplication process in In_(0.52)Al_(0.48)As. The model reproduces avalanche multiplication and excess noise factor measured on a wide range of In_(0.52)Al_(0.48) As p~+-n-n~+, n~+-n-p~+, and p~+-n~+ diodes and confirms that very low excess noise factor can be obtained using pure electron injection ia,very thick diodes with avalanche region greater than 2.21 μm or in very thin diodes with avalanche region lesser than 0.11 μm. In addition we investigated the effect of an electric field gradient in the avalanche region of avalanche photodiodes and found that the excess noise factor can be reduced with electric field gradients. However in thin diodes with avalanche region lesser than 0.20 μm, the onset of tunneling current negates the excess noise reduction achieved using the electric field gradient. Therefore ideal p~+-i-n~+rndiodes still provide the overall preferred structure.