On optimal structure and geometry of high-speed integrated photodiodes in a standard CMOS technology

Analyses of the influence of different geometries (layouts) and structures of high-speed CMOS photodiodes on their intrinsic (physical) and electrical bandwidths are presented. Three photodiode structures are studied: nwell/p-substrate, p+/nwell/p-substrate and p+/nwell. According to the author´s knowledge, this is a first time that the influence of various structures and geometries (layouts) of CMOS photodiodes on their bandwidth is analytically analysed.