Patent ID: 7022594

Claim:
A method for manufacturing a gate electrode structure comprising: a step for forming an insulating film on a surface of a semiconductor substrate; a step for forming an impurity diffused polysilicon film on said insulating film; a step of forming an impurity diffusion preventing film on said impurity diffused polysilicon film; a step for forming a refractory metal silicide film on said impurity diffusion preventing film; a step for forming a nitride film on said refractory metal silicide film; a step for patterning said impurity diffused polysilicon film, said impurity diffusion preventing film, said refractory metal silicide film and said nitride film as a gate electrode; a step for forming a first spacer constituted by a silicon-based film on side surfaces of said gate electrode; and an oxidation step for forming said first spacer into an oxide film, wherein said silicon-based film is a polysilicon film.