Method and system for forming a stacked gate insulating film

摘要

A stacked gate insulating film comprises a silicon oxide film and a tantalum oxide film which is stacked on the silicon oxide film and whose dielectric constant is higher than a dielectric constant of the silicon oxide film. The stacked gate insulating film is formed in accordance with the following steps. A semiconductor wafer is heated up, and the surface thereof is heat-oxidized. The silicon oxide film is formed on the semiconductor wafer (heat oxidation process). The silicon oxide film is etched back so as to be made thin (etch back process). The tantalum oxide film is stacked on the thin silicon oxide film (dielectric film formation process), thereby to form the stacked gate insulating film.