STACKED GATE ELECTRODE AND METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE WITH THE SAME

摘要

PURPOSE: A stacked gate electrode and a method for manufacturing a semiconductor device with the same are provided to reduce sheet resistance by preventing the formation of an interface oxide layer between a silicon layer and a metal film using a diffusion barrier layer. CONSTITUTION: A gate oxide layer(22) is formed on a substrate(21). A silicon layer(23) is formed on the gate oxide layer. A diffusion barrier layer(28) containing metal element capable of reacting oxygen is formed on the silicon layer. A metal film(25) is formed on the diffusion barrier layer. A stacked gate electrode is formed by etching the metal film, the diffusion barrier layer, the silicon layer. By performing selective oxidation processing, a GGO(Graded Gate Oxide) layer(22a) is formed at edges of the gate electrode.