SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD THEREOF

摘要

PROBLEM TO BE SOLVED: To form a stable gate electrode even in the manufacturing case of material for gate insulating film which is impossible to set a large selection ratio for etching with polysilicon. SOLUTION: An oxidation treatment of a polysilicon 31 is performed to form an oxide layer 32 with a silicide layer 4 and a nitride film 5 on the polysilicon 31 as a mask. The polysilicon is left only around the center of the lower silicide layer 4 and surrounded with the oxide layer 32 in the periphery thereof. In other words, the polysilicon is shaped using the silicide layer 4 in the self-aligning manner. Therefore, no etching is required to the polysilicon 31.