Patent ID: 6943051

Claim:
A method of fabricating a photodiode module monolithically integrated with a CMOS structure in a semiconductor substrate, comprising the steps of: (a) In said semiconductor substrate, forming at least one photo-diode active area surrounded by field oxide (FOX) regions, using any isolation technologies of CMOS processes, said photo-diode active area containing at least one embedded well semiconductor region implanted therein, said embedded well semiconductor region having a defined polarity, said embedded semiconductor well being surrounded laterally and underneath by semiconductor regions implanted with doping impurities of the opposite polarity, said embedded semiconductor well extending itself under a selected portion of the surrounding field oxide regions and overlapping at least a fraction of a selected adjacent active area, said overlapped fraction of adjacent active area including a surface region with high doping concentration of the same polarity of the embedded semiconductor well; (b) epitaxially growing photosensitive layers on said at least one photo-diode active area, said photosensitive layers comprising at least a doped semiconductor material having the opposite polarity as that of the embedded well semiconductor region underneath; (c) forming an ohmic contact region on at least one selected area of each of said epitaxially grown photosensitive layers; (d) forming a columnar metal interconnect layer on top of each selected area of said epitaxially grown photosensitive layer; and (e) forming a planarized dielectric layer on the non-selected areas of said epitaxially grown photosensitive layers up to the top level of said metal interconnect layer.