Patent ID: 8247296

Claim:
A method of forming a semiconductor device comprising the steps of: providing a semiconductor substrate having a major surface; forming a dielectric stack overlying the major surface, wherein the dielectric stack comprises a first layer and second layer overlying the first layer, and wherein one layer comprises an oxidation blocking layer; forming a first opening in the dielectric stack; forming a trench in the semiconductor substrate through the opening and extending from the major surface; forming an insulated shield electrode within the trench; removing the second layer; forming an insulated gate electrode within the trench, wherein the insulated gate electrode includes a conductive gate material; removing a portion of the conductive gate material to form a first recessed region above the insulated gate electrode; forming a dielectric plug within the first recessed region, wherein the dielectric plug comprises a material different than the first layer; forming a body region in the semiconductor substrate; removing the first layer; forming a source region in the body region self-aligned to the dielectric plug; forming dielectric spacers adjacent the dielectric plug; forming second recessed regions in the semiconductor substrate self-aligned to the spacers; and forming a first conductive layer coupled to the semiconductor substrate through the second recessed regions.