Patent ID: 7851325

Claim:
A method of manufacturing a semiconductor device, comprising: providing a substrate, forming a buried stressor layer over the substrate and forming an active layer over the buried stressor layer, the buried stressor layer between the substrate and the active layer, the buried stressor layer formed in a stressed state in comparison to the substrate when the buried stressor layer is formed, the buried stressor layer having a stressed surface adjacent the active layer when the active layer is formed; forming a sacrificial stressor layer over the active layer, the sacrificial stressor layer formed in a stressed state in comparison to the active layer when the sacrificial stressor layer is formed; and etching trenches through the active layer, through the buried stressor layer and into at least a portion of the substrate so that the etching trenches stresses at least a portion of the active layer and relaxes stress in at least portions of the buried stressor layer.