Monolithically Integrated Photo-Diodes in Standard CMOS Technology for high speed optical communication: General Consideration and Analysis

Photodiodes designed in standard CMOS technology which can be monolithically integrated in high-speed optical receivers are analyzed and the advantages and drawbacks concerning bandwidth with respect to the diode geometry and structure, are discussed. Studied photodiode structures that can be realized in standard CMOS technology are:\ud 1) N-well/Psubstrate,\ud 2) lateral N-well/P-substrate (exploiting only depletion region in between)\ud 3) N+/P-substrate and\ud 4) P+/N-well/P-substrate diodes.\ud The maximal operating frequency as well as the impulse response of the diodes are calculated using 2-D model semiconductor device analysis