| 摘要 |
PURPOSE: A gate electrode is to prevent damage of a gate oxide film by placing an etching stop layer between a conductive layer and a polycrystalline silicide layer to prevent a polysilicon layer from being etched when the conductive layer is etched. CONSTITUTION: A semiconductor substrate(210) is defined by an active region and an inactive region by a shallow trench isolation region(212) and has a gate oxide film(220) formed thereon. A polysilicon layer(232), an etching stop layer(233) and a tungsten silicide layer(234) are sequentially deposited on the semiconductor substrate. A titanium silicide(TiSi), a cobalt silicide(CoSi) or a tungsten is applicable instead of the tungsten silicide. Then, a nitriding silicon mask pattern(236) is formed on the tungsten silicide layer. The tungsten silicide layer is anisotropically etched to be selectively etched with regard to the etching stop layer using a mask pattern as an etching mask. Since a selective etching ratio of the tungsten silicide layer to the etching stop layer is large, etching of the polysilicon layer is prevented.
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