Patent ID: 8384160

Claim:
A semiconductor device comprising: a first nMIS transistor having a first nMIS threshold voltage; and a second nMIS transistor having a second nMIS threshold voltage, wherein the first nMIS transistor includes: a first nMIS channel region provided over a semiconductor substrate; a first nMIS high-k film provided over the first nMIS channel region and containing at least either of lanthanum and magnesium; and a first nMIS metal electrode provided over the first nMIS high-k film, wherein the second nMIS transistor includes: a second nMIS channel region provided over a semiconductor substrate; a second nMIS high-k film provided over the second nMIS channel region; and a second nMIS metal electrode provided over the second nMIS high-k film, wherein the absolute value of the second nMIS threshold voltage is greater than the absolute value of the first nMIS threshold voltage, and wherein the sum of the concentration of lanthanum atom and the concentration of magnesium atom in the second nMIS high-k film is lower than the sum of the concentration of lanthanum atom and the concentration of magnesium atom in the first nMIS high-k film.