Patent ID: 7507630

Claim:
A method of fabricating a semiconductor device with a semiconductor body and a trench gate formed in a cell area thereof, comprising: forming an insulating film on the semiconductor body to cover a termination area surrounding the cell area; forming a mask material film to cover the cell area and the insulating film; forming a resist film to cover the mask material film; patterning the resist film to have an opening serving as a gate-use resist pattern above the cell area and another opening serving as a dummy resist pattern above the insulating film; selectively etching the mask material film by use of the patterned resist film as a mask so that the insulating film is remained under the dummy resist pattern; selectively etching the semiconductor body by use of the patterned mask material film as another mask to form a trench in the cell area as corresponding to the gate-use resist pattern; and burying gate material in the trench to form the trench gate.