Patent ID: 7575975
Filing Date: 2009-08-18
Classification: H01L,Y10S

Abstract:
1. A method for forming a semiconductor structure, the method comprising: providing a substrate, said substrate comprising a strained semiconductor layer overlying an insulating layer; providing a first device region for forming a first plurality of devices having a first conductivity type; providing a second device region for forming a second plurality of devices having a second conductivity type, wherein the second conductivity type is different than the first conductivity type; wherein the first plurality of devices comprise planar devices and the second plurality of devices comprise vertical devices; thickening the strained semiconductor layer in the second device region to form a thickened strained semiconductor layer so that the thickened strained semiconductor layer in the second device region has less strain than the strained semiconductor layer in the first device region; wherein said step of thickening comprises: epitaxially growing a same semiconductor material as the strained semiconductor layer directly on the strained semiconductor layer to form the thickened semiconductor layer; wherein said step of thickening comprises: forming a masking layer overlying the first device region, and performing selective epitaxial growth to thicken the strained semiconductor layer in the second device region and not in the first device region; wherein a thickness of a portion of the strained semiconductor layer which is epitaxially grown is thicker than a thickness of the masking layer; and forming the first plurality of devices in the first device region and the second plurality of devices in the second device region, wherein source/drain regions of the first plurality of devices are formed within the strained semiconductor layer and source/drain regions of the second plurality of devices are formed within the thickened strained semiconductor layer, wherein said step of forming the second plurality of devices in the second device region comprises: