US Patent 7119403 High performance strained CMOS devices

A semiconductor device and method of manufacture provide an n-channel field effect transistor (nFET) having a shallow trench isolation with overhangs that overhang Si—SiO2 interfaces in a direction parallel to the direction of current flow and in a direction transverse to current flow. The device and method also provide a p-channel field effect transistor (pFET) having a shallow trench isolation with an overhang that overhangs Si—SiO2 interfaces in a direction transverse to current flow. However, the shallow trench isolation for the pFET is devoid of overhangs, in the direction parallel to the direction of current flow.