Crosstalk effects of avalanche CMOS photodiodes

This work explores crosstalk effects of avalanche CMOS photodiodes in a 3D sensor array where photodiodes were implemented under different shapes, perimeters, areas, structures and array sizes using the TSMC 0.35μm technology. The breakdown voltages are increased with areas and depths of p-n junctions, and decreased as perimeters of p-n junctions and array sizes increasing. The preferred shape of a photodiode tends to be a circle. Particularly, the breakdown voltage of an avalanche CMOS photodiode with the crosstalk effect is derived based on its physical characteristics. The proposed mathematical model can be beneficial to the design of avalanche CMOS photodiodes in a sensor array.