Patent ID: 8389316

Claim:
A method of forming a semiconductor structure, the method comprising: forming an isolation region in a semiconductor substrate, wherein the isolation region adjoins an active region in the semiconductor substrate; forming a metal-oxide-semiconductor (MOS) device comprising: forming a gate electrode over the active region; and forming a source region and a drain on opposing sides of the gate electrode; forming a stressor layer over the active region and the isolation region; and forming a strain bar overlaying the isolation region, wherein the strain bar is encircled by the stressor layer, wherein the steps of forming the stressor layer and the strain bar comprise: blanket forming a dummy stressor layer having an opposite stress type than the stressor layer; etching the dummy stressor layer to leave the strain bar; forming the stressor layer over the strain bar and the MOS device; and etching a portion of the stressor layer directly over the strain bar.