Strained channel integrated circuit devices

A device comprising:

• a substrate;
• first and second projections extending upwardly from the substrate, the first projection having a tensile-strained first channel region therein and the second projection having a compression-strained second channel region therein;
• and
• first and second gate structures engaging the first and second projections adjacent to the first and second channel regions, respectively;
• wherein the first gate structure includes:
• a dielectric layer adjacent the first channel region;
• a first conductive layer disposed over the dielectric layer;
• a strain-inducing conductive layer disposed over the first conductive layer;
• and
• a second conductive layer disposed over the strain-inducing conductive layer;
• and
• wherein the second gate structure includes:
• a high-k dielectric layer adjacent the second channel region;
• and
• a metal layer disposed over the high-k dielectric layer.

A device comprising:

• a substrate;
• a first fin-like field effect transistor (FinFET) disposed on the substrate, the first FinFET including:
• a first strained channel region;
• a first dielectric layer disposed at least partly over the first strained channel region, the first dielectric layer including an interfacial layer physically in contact with the first strained channel region;
• a barrier layer disposed at least partly over the first strained channel region and physically in contact with the first dielectric layer;
• a first polysilicon layer disposed at least partly over the first strained channel region and physically in contact with the barrier layer;
• a strain-inducing layer disposed at least above the first strained channel region and imparting at least a portion of the strain in the first strained channel region;
• and
• a second polysilicon layer disposed at least partly over the first strained channel region and physically in contact with the strain-inducing layer;
• and
• a second FinFET disposed on the substrate, the second FinFET including:
• a second strained channel region, the second strained channel region being strained in a different manner than the first strained channel region;
• a high-k second dielectric layer disposed at least above the second strained channel region;
• a U-shaped work function metal layer disposed over the high-k second 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.