Patent ID: 8158453

Claim:
A method for forming an active pixel sensor (APS) cell structure comprising the steps of: providing a substrate of a first conductivity type material; forming a transfer gate device comprising a gate dielectric layer formed on the substrate and a dual workfunction gate conductor layer formed on the gate dielectric layer, said dual workfunction gate conductor layer comprising a first doped region of first conductivity type material and a second doped region of a second conductivity type material; forming a photosensing device at or below a substrate surface adjacent said first doped region of said transfer gate device for collecting charge carriers in response to light incident thereto; forming a diffusion region of a second conductivity type material at said substrate surface adjacent said second doped region of said transfer gate device, said transfer gate device forming a conducting channel region enabling charge transfer between said photosensing device and said diffusion region; and, forming a silicide structure atop said dual workfunction gate conductor layer for electrically coupling said first doped region of first conductivity type material of said transfer gate device and said second doped region of second conductivity type material of said transfer gate device, wherein said formed silicide structure is smaller in area dimension than an area dimension of said dual workfunction gate conductor layer.