Effect of Soft Dead Space on the Mean Gain of Avalanche Photodiodes in Submicron Ranges

A novel modified model which accounts for both the effect of dead space and soft ionization rate in the multiplication process of avalanche photodiodes (APDs) is proposed. The application of the suggested model is intended to be mainly beneficial in simulating gain characteristics of thin APDs in which considering the realistic ionization events and physical multiplication phenomena is inevitable. Based on the proposed soft dead space model, renewal arguments governing mean multiplication gain of APDs have been achieved.