Patent ID: 7387908
Filing Date: 2008-06-17
Classification: H01L

Abstract:
1. A method of forming a pixel sensor cell, said method comprising: forming a charge collection region and a floating diffusion region in a substrate; forming a gate of a transfer transistor, over said substrate, for transferring charge from said charge collection region to said floating diffusion region; forming a non-uniformly doped region having a lateral dopant gradient of a first conductivity type in said substrate and below said gate, said dopant gradient decreasing in conductivity from said charge collection region to said floating diffusion region; forming a first doped layer of said first conductivity type in said substrate, said first doped layer being displaced laterally from an electrically active portion of said gate by a predetermined distance; and wherein said charge collection region is of a second conductivity type and is formed in said substrate below said first doped layer.