A structure of a MIS transistor for realizing a CMOS circuit capable of simultaneously achieving the high ON current and the low power consumption is provided. Each of the gate insulators of a n channel MIS transistor and a p channel MIS transistor is composed of a hafnium oxide film. Also, the gate electrode is composed of a Pt silicide film with a ratio of Si atoms to Pt atoms of approximately 1 (PtSix: x=1) in the vicinity of a region in contact with the gate insulator. Also, the gate electrode of the p channel MIS transistor is composed of a Pt silicide film with a ratio of Si atoms to Pt atoms of less than 1 (PtSix: x