Abstract: A structure for an integrated circuit is disclosed. The structure includes a crystalline substrate and four crystalline layers. The first crystalline layer of first lattice constant is positioned on the crystalline substrate. The second crystalline layer has a second lattice constant different from the first lattice constant, and is positioned on said first crystalline layer. The third crystalline layer has a third lattice constant different than said second lattice constant, and is positioned on said second crystalline layer. The strained fourth crystalline layer includes, at least partially, a MOSFET device.

Abstract: A structure for an integrated circuit is disclosed. The structure includes a crystalline substrate and four crystalline layers. The first crystalline layer of first lattice constant is positioned on the crystalline substrate. The second crystalline layer has a second lattice constant different from the first lattice constant, and is positioned on said first crystalline layer. The third crystalline layer has a third lattice constant different than said second lattice constant, and is positioned on said second crystalline layer. The strained fourth crystalline layer includes, at least partially, a MOSFET device.

Abstract: A method of forming a strained silicon layer on a relaxed, low defect density semiconductor alloy layer such as SiGe is provided.

Abstract: A method of forming a strained silicon layer on a relaxed, low defect density semiconductor alloy layer such as SiGe, has been developed. In a first embodiment of this invention the relaxed, low density SiGe layer is epitaxially grown on an silicon layer which in turn is located on an underlying SiGe layer. During the epitaxial growth of the overlying SiGe layer defects are formed in the underlying silicon layer resulting in the desired, relaxation, and decreased defect density for the SiGe layer. A second embodiment features an anneal procedure performed during growth of the relaxed SiGe layer, resulting in additional relaxation and decreased defect density, while a third embodiment features an anneal procedure performed to the underlying silicon layer prior to epitaxial growth of the relaxed SiGe layer, again allowing optimized relaxation and defect density to be realized for the SiGe layer.