Simulation and Design of a High Responsibility PIN Photodetector

A silicon-based PIN photodetector structure with the characteristics of high responsibility and high cut-off frequency fabricated with the PERL(the passivated emitter and the rear locally-diffused)technologies is introduced in this paper.After making some tiny adjustments of the structure,Silvaco software is used to simulate three similar structures of PIN photodetector by measuring the spectral response,dark current,cut-off frequency and dc characteristics.From the results,it is concluded that PIN photodetector with the middle shallow diffusion area is superior to the other two ones in dark current,at least 35% lower.The responsibility of these three kinds of detector reaches the degree of 0.3A/W,and the highest spectral response is around 600nm.Their cut-off frequencies are all over 108Hz.