Semiconductor device

A method of manufacturing a semiconductor device, comprising:

• forming an n-type semiconductor region and a p-type semiconductor region on a semiconductor substrate;
• forming a second gate dielectric layer above the n-type semiconductor region and the p-type semiconductor region;
• forming a first gate dielectric layer above the n-type semiconductor region, the first gate dielectric layer being made of an insulating material different from that of the second gate dielectric layer, the first gate dielectric layer and the second gate dielectric layer being formed of an oxide layer including a first element of at least one metal element selected from the group consisting of Zr, Hf, Ti, Ta, Nb, V, Sc, Y, a lanthanoide series and a actinide series;
• and
• forming a gate electrode layer over the n-type semiconductor region and the p-type semiconductor region, after said forming a first gate dielectric layer and said forming a second gate dielectric layer, wherein an atomic density of the first element in a portion of the second pate gate dielectric layer in contact with the gate electrode layer is lower than an atomic density of the first element in a portion of the first pate gate dielectric layer in contact with the gate electrode layer.

A semiconductor device comprising:

• a semiconductor substrate;
• an nMISFET including a first dielectric disposed above the semiconductor substrate and a first metal gate electrode formed on the first dielectric;
• and
• a pMISFET including a second dielectric disposed above the semiconductor substrate and a second metal gate electrode disposed above the second dielectric,
• wherein the first dielectric in contact with the first metal gate electrode and the second dielectric in contact with the second metal gate electrode include a first element of at least one element selected from the group consisting of Zr, Hf, Ti, Ta, Nb, V, Sc, Y, a lanthanoide series and an actinide series, and at least the first dielectric includes a second element selected from a group consisting of Al, Si and Ge, and an atomic density of the second element in the second dielectric is lower than an atomic density of the second element in the first dielectric.

A method of manufacturing a semiconductor device, comprising:

• forming an nMISFET including a first dielectric disposed above a semiconductor substrate and a first metal gate electrode formed on the first dielectric;
• and
• forming a pMISFET including a second dielectric disposed above the semiconductor substrate and a second metal gate electrode disposed above the second dielectric,
• wherein the first dielectric in contact with the first metal gate electrode and the second dielectric in contact with the second metal gate electrode include a first element of at least one element selected from the group consisting of Zr, Hf, Ti, Ta, Nb, V, Sc, Y, a lanthanoide series and an actinide series, and at least the first dielectric includes a second element selected from a group consisting of Al, Si and Ge, and an atomic density of the second element in the second dielectric is lower than an atomic density of the second element in the first dielectric.