Patent ID: 7741169

Claim:
A method of forming a complementary MOSFET consisting of a PMOSFET and an NMOSFET, comprising: providing a semiconductor substrate with regions of a PMOSFET and an NMOSFET; forming a compressively strained film overlying the PMOSFET channel; forming gate dielectric layers on the NMOSFET region and the compressively strained film, respectively; forming gate electrodes on the gate dielectric layers; and forming a cap layer overlying the NMOSFET region for producing a local tensile stress on a channel of the NMOSFET; wherein formation of the compressively strained film overlying the PMOSFET region comprises: forming an amorphous layer overlying the semiconductor substrate, including the PMOSFET and the NMOSFET regions; removing the amorphous layer overlying the PMOSFET region; and forming the compressively strained film overlying the PMOSFET region by selective epitaxy.