Patent ID: 8729627

Claim:
A device comprising: a substrate having a first strained channel region and a second strained channel region therein, the second channel region being strained in a different manner than the first channel region; a first gate structure including: a dielectric layer disposed at least partly over the first channel region, the dielectric layer including an interfacial layer physically in contact with the first channel region; a barrier layer disposed at least partly over the first channel region and physically in contact with the dielectric layer; a first conductive layer disposed over the barrier layer, and having a characteristic with a first value; a strain-inducing conductive layer disposed over the first conductive layer, and having the characteristic with a second value, wherein the second value is different from the first value; and a second conductive layer disposed over the strain-inducing conductive layer, and having the characteristic with the first value; and a second gate structure including: a high-k dielectric layer disposed at least partly over the second channel region; a U-shaped work function metal layer disposed over the high-k dielectric layer, the U-shaped work function metal layer forming an opening having opposing surfaces therein; and a metal fill layer disposed at least partially within the opening such that the metal fill layer is in physical contact with the opposing surfaces.