A Device Model Simulation of Neutron Radiation Effects in Avalanche Photodiodes

A one-dimensional ( 1-D) steady state drift-diffusion model that incorporates impact ionisation has been developed for the simulation of avalanche photodiodes. The model uses finite difference analysis to solve the time-independent semiconductor equations across a user specified structure. The model includes DC illumination, allowing wavelength dependent effects to be modelled. The effect of neutron radiation damage is included via the introduction of deep acceptor levels subject to Shockley-Read-Hall statistics. Preliminary analysis of an EG&G reverse reach through APD structure has been performed.