Adjusting of strain caused in a transistor channel by semiconductor material provided for threshold adjustment

A method, comprising:

• forming a threshold-adjusting semiconductor material on a silicon-containing semiconductor region;
• providing a strain-adjusting species at least in said threshold-adjusting semiconductor material;
• and
• forming a gate electrode structure of a transistor above said threshold-adjusting semiconductor material, said gate electrode structure comprising a high-k dielectric material formed at least above said threshold-adjusting semiconductor material, said gate electrode structure further comprising a metal-containing electrode material formed above said high-k dielectric material.

A transistor, comprising:

• a silicon-containing semiconductor region formed above a substrate;
• a gate electrode structure formed above said silicon-containing semiconductor region, said gate electrode structure comprising a high-k gate insulation layer and a metal-containing electrode material formed on said high-k gate insulation layer;
• and
• a channel region comprising a threshold-adjusting semiconductor material comprising a first tetravalent non-silicon species that is in contact with said high-k gate insulation layer, said channel region further comprising a strain adjustment tetravalent non-silicon species that is different from a said first non-silicon species.