Patent ID: 6194273
Filing Date: 2001-02-27
Classification: H01L

Abstract:
A manufacturing method of an insulated-gate type semiconductor device comprising the steps of:sequentially forming a silicon oxide film of a predetermined film thickness and a silicon nitride film of a predetermined film thickness on a semiconductor body, said predetermined thickness of said silicon oxide film being in a range of 400 to 600 .ANG. and said predetermined thickness of said silicon nitride film being in a range of 600 to 1000 .ANG.;forming an initial groove on said semiconductor body by etching;forming an LOCOS oxide film on an inner surface of said initial groove by thermal oxidization at 1100 to 1200.degree. C. using said nitride film as a mask, thereby forming and deforming said initial groove into a U-shaped groove; andremoving said LOCOS oxide film and sequentially forming a gate oxide film and a polysilicon gate electrode on an inner surface of said U-shaped groove and a shoulder.