Patent ID: 6207540
Filing Date: 2001-03-27
Classification: H01L

Abstract:
A method for manufacturing a semiconductor device, comprising the steps of:(a) providing a substrate;(b) doping a surface of the substrate to a first depth to form a diffusion layer;(c) forming a trench in the surface of the substrate wherein the trench has sidewalls, a bottom, and a depth greater than the first depth; and(d) doping the substrate adjacent the sidewalls of the trench and under a portion of the bottom of the trench to form a diffusion extension extending from the diffusion layer, along the sidewalls of the trench, and under the portion of the bottom of the trench by depositing a diffusible dopant layer containing a diffusible element in the trench and causing the diffusion of the diffusible element into the substrate adjacent the sidewalls of the trench and the portion of the bottom of the trench.