Patent ID: 8232605

Claim:
A complementary metal-oxide-semiconductor (CMOS) device, comprising: a semiconductor substrate comprising a P type metal-oxide-semiconductor (PMOS) region and an N type metal-oxide-semiconductor (NMOS) region; a first gate dielectric layer on the PMOS region and a second gate dielectric layer on the NMOS region of the semiconductor substrate; and a first gate structure and a second gate structure on the first gate dielectric layer and the second gate dielectric layer, respectively; wherein the semiconductor substrate of the PMOS region comprises a first dopant of a first concentration, the semiconductor substrate of the NMOS region comprises a second dopant of a second concentration, each of the first dopant and the second dopant is selected from the group consisting of fluorine and carbon; and the first concentration of the PMOS region and the second concentration of the NMOS region are different.