Patent ID: 7883973
Filing Date: 2011-02-08
Classification: H01L

Abstract:
1. A method of forming a semiconductor device, comprising: patterning a first mask layer over a dielectric layer formed on a substrate; removing exposed portions of said dielectric layer; implanting a first dopant into a first and a second unprotected region of said substrate through openings in said dielectric layer, resulting in a first and a second doped region; patterning a second mask layer over said dielectric layer, exposing said second doped region and a portion of said dielectric layer, but leaving a remaining portion of said second mask layer over said first doped region; implanting a second dopant into said second doped region through an opening in said dielectric layer; and implanting a third dopant into said second doped region through said opening, and into said substrate through said exposed portion of said dielectric layer, resulting in a third doped region.