Patent ID: 6372537
Filing Date: 2002-04-16
Classification: H01L

Abstract:
A method of forming an active pixel sensor, on a semiconductor substrate, comprising the steps of:forming a gate structure, for a reset transistor, on an underlying gate insulator layer, located on a first portion of a semiconductor substrate, of a first conductivity type; performing a first ion implantation procedure, of a second conductivity type simutaneously to form a source/drain region for said reset transistor, in an area of said first portion of said semiconductor substrate, not covered by said gate structure, and forming a readout region, in a section of a second portion of said semiconductor substrate; performing a second ion implantation procedure, of said second conductivity type to form a bottom segment of a pinned photodiode structure, in said second portion of said semiconductor substrate; performing a third ion implantation procedure, of said first conductivity type, to form a top segment of said pinned photodiode structure adjacent to the sides of the readout region, in an area of said second portion of said semiconductor substrate, not occupied by said readout region; and forming a metal contact structure, overlying and contacting, a top portion of said readout region.