Semiconductor device and method of manufacturing same

A semiconductor device comprising:

• a first pMIS transistor having a first pMIS threshold voltage;
• and
• a second pMIS transistor having a second pMIS threshold voltage,
• wherein the first pMIS transistor includes:
• a first pMIS channel region provided over a semiconductor substrate;
• a first pMIS high-k film provided over the first pMIS channel region and containing aluminum;
• and
• a first pMIS metal electrode provided over the first pMIS high-k film,
• wherein the second pMIS transistor includes:
• a second pMIS channel region provided over a semiconductor substrate;
• a second pMIS high-k film provided over the second pMIS channel region;
• and
• a second pMIS metal electrode provided over the second pMIS high-k film,
• wherein the absolute value of the second pMIS threshold voltage is greater than the absolute value of the first pMIS threshold voltage, and
• wherein the concentration of aluminum atom in the second pMIS high-k film is lower than the concentration of aluminum atom in the first pMIS high-k film.

A method of manufacturing a semiconductor device comprising the steps of:

• forming a first and a second nMIS channel region having a p-type conductive type by injecting p-type impurities onto a semiconductor substrate;
• forming a high-k film over the first and second nMIS channel regions;
• forming an nMIS cap film containing at least either of lanthanum and magnesium so as to cover the part over the first nMIS channel region of the high-k film and to expose the part over the second nMIS channel region of the high-k film;
• forming a first nMIS metal electrode over the first nMIS channel region via the high-k film and the nMIS cap film and forming a second nMIS metal electrode over the second nMIS channel region via the high-k film;
• and
• diffusing at least either of lanthanum and magnesium contained in the nMIS cap film into the part over the first nMIS channel region of the high-k film.

A method of manufacturing a semiconductor device comprising the steps of:

• forming a first and a second pMIS channel region having an n-type conductive type by injecting n-type impurities onto a semiconductor substrate;
• forming a high-k film over the first and second pMIS channel regions;
• forming a pMIS cap film containing aluminum so as to cover the part over the first pMIS channel region of the high-k film and to expose the part over the second pMIS channel region of the high-k film;
• forming a first pMIS metal electrode over the first pMIS channel region via the high-k film and the pMIS cap film and forming a second pMIS metal electrode over the second pMIS channel region via the high-k film;
• and
• diffusing aluminum contained in the pMIS cap film into the part over the first pMIS channel region of the high-k film.