Patent ID: 6864128

Claim:
A method of manufacturing a semiconductor device comprising the steps of: (a) forming a gate insulating film on a semiconductor substrate; (b) forming a first polysilicon film containing n-type impurities on said gate insulating film; (c) forming a second polysilicon film on said first polysilicon film, said second polysilicon film being a polysilicon film containing said impurities and having a concentration of said impurities lower than that of said first polysilicon film or a non-doped polysilicon film; (d) forming a gate electrode including said first and second polysilicon films on said gate insulating film by partly etching said first and second polysilicon films from the above of said second polysilcon film; and (e) forming a sidewall on a side surface of said gate electrode after accomplishing said step (d), wherein the etching applied to said first and second polysilicon films in said step (d) forms an etched side surface of said first polysilicon film recessed compared with that of said second polysilicon film, thereby leaving a notch on said side surface of said gate electrode, and said step (e) is performed in such a manner that said notch is filled with said sidewall.