Patent ID: 7960793

Claim:
A semiconductor device, comprising: a semiconductor substrate having a first semiconductor layer and a second semiconductor layer separated from each other; an nMIS transistor including, a first source region and a first drain region, formed in the first semiconductor layer and separated from each other, a first gate dielectric film covering a first channel region which is the first semiconductor layer between the first source region and the first drain region, and a first gate electrode formed on the first gate dielectric film and including an Hf oxide film or a Zr oxide film in which a first element selected from a first group comprising Nb and W is added, and a second element selected from a second group comprising N, C, B, Mg, Ca, Sr, Ba, Al, Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu is added; and a pMIS transistor including, a second source region and a second drain region, formed in the second semiconductor layer and separated from each other, a second gate dielectric film covering a second channel region which is the second semiconductor layer between the second source region and the second drain region, and a second gate electrode formed on the second gate dielectric film and including an Hf oxide film or a Zr oxide film in which the first element is added, and the second element is added in a larger amount than that in the first gate electrode.