US Patent 7666785 Method for fabricating semiconductor device with interface barrier

A method for fabricating a semiconductor memory device includes forming a first layer, injecting a tungsten source gas and a silicon source gas simultaneously to form a tungsten silicide layer over the first layer, forming a tungsten nitride layer over the tungsten silicide layer without a post purge process of additionally supplying the silicon source gas, and forming a second layer over the tungsten nitride layer.