A new p⁺-i-n⁺ photodiode SPICE model for CMOS pixel applications

In this paper we discuss and model the effects of the density of defects in hydrogenated amorphous silicon from an electronics point of view. To this end, we have created a SPICE model that accounts for the two main field effects, Poole-Frenkel and tunnel, responsible for the leakage current. The comparison between our model and the experimental data shows that our approach allows a quick evaluation of the quality of the device with no need to run a complete steady state measurement. Also, we have validated our SPICE photodiode model by implementing it into a three CMOS simple pixel structure.