Advanced Design of Schottky Photodiodes in Bulk CMOS for High Speed Optical Receivers

Abstract

This paper provides theoretical insight on how circular Schottky photodiodes in bulk CMOS can be optimized for certain integrated receiver applications. An optimal photodiode size is analytically demonstrated and the effects of a metal plate reflector are simulated using a transfer-matrix method, both for frontside and backside illumination. Finally, a distributed circuit model is presented, which deviates from the classical lumped model for large photodiodes or sheet resistances. The presented methodologies can also be extended to other types of photodetectors.