Patent ID: 8415753

Claim:
A semiconductor device, which comprises a field effect transistor provided on a silicon substrate and having a gate insulating film and a first gate electrode provided on the gate insulating film, wherein the gate insulating film has a high-permittivity insulating film formed of a metal oxide, a metal silicate, a metal oxide introduced with nitrogen, or a metal silicate introduced with nitrogen, the first gate electrode has a first metal nitride layer provided on the gate insulating film and containing Ti and N, a second metal nitride layer provided on the first metal nitride layer and containing Ti and N, and a first polycrystalline silicon layer provided on the second metal nitride layer, in the first metal nitride layer, a molar ratio of N to Ti (N/Ti) is not less than 1.1, and a first crystalline orientation X1 is 1.1<X1<1.8, where X1 is a first ratio of C200 to C111, and C200 and C111 are the peak intensity measurements of the respective 200 and 111 crystal orientations from the x-ray diffraction of the first metal nitride layer, and in the second metal nitride layer, the molar ratio of N to Ti (N/Ti) is not less than 1.1, and a second crystalline orientation X2 is 1.8≦X2, where X2 is a second ratio of C200 to C111, and C200 and C111 are the peak intensity measurements of the respective 200 and 111 crystal orientations from the x-ray diffraction of the second metal nitride layer.