Patent ID: 7041561
Filing Date: 2006-05-09
Classification: H01L

Abstract:
1. A method of forming a semiconductor structure in a semiconductor wafer, the method comprising the steps of: forming an epitaxial layer on a least a portion of a semiconductor substrate of a first conductivity type; forming at least one trench in an upper surface of the semiconductor wafer and partially into the epitaxial layer; forming at least one diffusion region between a bottom wall of the at least one trench and the substrate, the at least one diffusion region providing an electrical path between the bottom wall of the at least one trench and the substrate; doping at least one or more sidewalls of the at least one trench with a first impurity so as to form an electrical path between an upper surface of the epitaxial layer and the at least one diffusion region; and substantially filling the at least one trench with a filler material; wherein the step of doping at least one or more sidewalls of the at least one trench is performed after the step of forming the at least one diffusion region.