METHOD FOR MANUFACTURING GATE OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for manufacturing a gate of a semiconductor device is provided to obtain a superior interface smoothness between a polysilicon layer and a titanium silicide layer of a crystalline state, by forming a titanium silicide layer of a high composition ratio by a chemical vapor deposition(CVD) process and without generating particles. CONSTITUTION: A gate oxide layer(42) and a polysilicon layer(43) are sequentially formed on a semiconductor substrate(41). A titanium silicide layer having an amorphous state and a composition ratio more than 2.3 is formed on the polysilicon layer by a chemical vapor deposition(CVD) process. A heat treatment is performed regarding the substrate to transform the titanium silicide layer to a titanium silicide layer(44A) of a crystalline state. A hard mask layer(45) is formed on the titanium silicide layer of the crystalline state. The hard mask layer, the titanium silicide layer of the crystalline state and the polysilicon layer are etched to form a gate electrode(400) of a polycide structure. The substrate is oxidized by a gate re-oxidation process to form a re-oxidation layer on the sidewall of the gate electrode and on the substrate.