Manufacturing method which prevents abnormal gate oxidation

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 an amorphous silicon film.

A method for manufacturing a gate electrode structure, comprising:

• forming an insulating film on a surface of a semiconductor substrate;
• forming an impurity diffused polysilicon film on said insulating film;
• forming an impurity diffusion preventing film on said impurity diffused polysilicon film;
• forming a refractory metal silicide film on said impurity diffusion preventing film;
• forming a nitride film on said refractory metal silicide film;
• patterning said impurity diffused polysilicon film, said impurity diffusion preventing film, said refractory metal silicide film and said nitride film as a gate electrode;
• forming a first spacer constituted by a silicon-based film on side surfaces of said gate electrode;
• and
• oxidizing said first spacer into an oxide film,
• wherein said silicon-based film is a polysilicon film.

A method for manufacturing a gate electrode structure, comprising:

• forming an insulating film on a surface of a semiconductor substrate;
• forming an impurity diffused polysilicon film on said insulating film;
• forming an impurity diffusion preventing film on said impurity diffused polysilicon film;
• forming a refractory metal suicide film on said impurity diffusion preventing film;
• forming a nitride film on said refractory metal suicide film;
• patterning said impurity diffused polysilicon film, said impurity diffusion preventing film, said refractory metal silicide film and said nitride film as a gate electrode;
• forming a first spacer constituted by a silicon-based film on side surfaces of said gate electrode;
• and
• oxidizing said first spacer into an oxide film,
• wherein said silicon-based film is an amorphous silicon film.