METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE AND SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing a semiconductor device and a semiconductor device, capable of compatibly achieving a low 1/f noise and a high operation speed in product units.SOLUTION: A method for manufacturing a semiconductor device comprises steps of: forming a gate oxide film 4 on a silicon substrate 1; forming a polysilicon film 5 on the gate oxide film 4; forming a tungsten silicide 6 on the polysilicon film 5; forming a gate electrode 51 of a single layer structure composed of the polysilicon film 5 in a first element region R1 of the silicon substrate 1 by sequentially patterning the tungsten silicide 6 and the polysilicon film 5 and forming a gate electrode 61 of a double-layer structure composed of the polysilicon film 5 and the tungsten silicide 6 in a second element region R2; and forming an impurity diffusion layer 10 by injecting BFinto the silicon substrate 1 using the first gate electrode 51 and a second gate electrode 61 as a mask.