METHOD FOR FORMING GATE OXIDE FILM IN SEMICONDUCTOR DEVICES

摘要

PURPOSE: A gate oxide formation method in semiconductor devices is provided to be capable of increasing reliability by NO-oxynitride film as an underlying oxide film and easily controlling the thickness of the oxide film due to a low growth ratio. CONSTITUTION: An underlying oxide film is first grown using NO gas in the furnace. A Ta2O5 film(6) is then deposited on the underlying oxide film. After depositing a silicon nitride film(7) on the Ta2O5 film, annealing process is performed under N2O atmosphere in the furnace. Next, polysilicon(8) is deposited on the silicon nitride film.