Patent ID: 7282429

Claim:
A method of manufacturing an IC device, comprising: providing a substrate; forming a gate oxide layer on said substrate; forming a polysilicon layer on said gate oxide layer; partially oxidizing said polysilicon layer to form a poly oxide layer on said polysilicon layer; forming and defining a photoresist layer on said poly oxide layer for exposing parts of said poly oxide layer; executing a first etch via said photoresist layer to etch the exposed parts of said poly oxide layer for forming a poly oxide structure; executing a second etch via said photoresist layer to etch said polysilicon layer and said gate oxide layer for forming a polysilicon structure and a gate oxide structure; removing said photoresist layer and executing an ion implantation process to form a first implanted region in said substrate and a second implanted region in said polysilicon structure respectively; and forming a conducting structure on said first implanted region, said second implanted region and said poly oxide structure for obtaining said IC device; wherein said gate oxide layer is formed by a first thermal oxidation, said polysilicon layer is formed by an LPCVD process, and said polysilicon layer is partially oxidized by a second thermal oxidation, and wherein said second thermal oxidation is performed under a mixed gas of oxygen and hydrogen in a ratio ranging from about 1:1 to about 3:5.