METHOD FOR FORMING STACKED GATE ELECTRODE OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for forming a stacked gate electrode of a semiconductor device is provided to prevent RC delay by preventing the formation of an interface oxide layer between a polysilicon layer and a metal film. CONSTITUTION: A gate oxide layer(22) is formed on a semiconductor substrate(21). A silicon layer(23) is formed on the gate oxide layer. A tungsten nitride layer(24) is formed on the silicon layer. A stacked gate electrode is formed by patterning the tungsten nitride layer and the silicon layer. A spacer forming layer containing Si is formed on the resultant structure. A spacer is formed at both sidewalls of the stacked gate electrode by etch-back of the spacer forming layer. By performing selective oxidation processing, a GGO(Graded Gate Oxide) layer(22a) and an oxide spacer(26b) are simultaneously formed.