CMOS IMAGER PHOTODIODE WITH ENHANCED CAPACITANCE

摘要

A method for manufacturing a pixel sensor cell that includes a photosensitive element having a non-laterally disposed charge collection region. The method includes forming a trench recess in a substrate of a first conductivity type material, and filling the trench recess with a material having second conductivity type material. The second conductivity type material is then diffused out of the filled trench material to the substrate region surrounding the trench to form the non-laterally disposed charge collection region. The filled trench material is removed to provide a trench recess, and the trench recess is filled with a material having a first conductivity type material. A surface implant layer is formed at either side of the trench having a first conductivity type material. A collection region of a trench-type photosensitive element is formed of the outdiffused second conductivity type material and is isolated from the substrate surface.