Patent ID: 7202142

Claim:
A method for forming a strained silicon layer device with improved wafer throughput and low defect density comprising the steps of: providing a silicon substrate; epitaxially growing a first silicon layer using at least one deposition precursor selected from the group consisting of disilane, trisilane, dichlorosilane, and silane; epitaxially growing a step-grade SiGe buffer layer over and contacting the first silicon layer using at least one deposition precursor selected from the group consisting of disilane and trisilane; epitaxially growing a SiGe capping layer over and contacting the step-grade SiGe buffer layer using at least one deposition precursor selected from the group consisting of disilane and trisilane; epitaxially growing a second silicon layer using at least one deposition precursor selected from the group consisting of disilane, trisilane, dichlorosilane, and silane; and forming a gate oxide and polysilicon gate electrode over the second silicon layer.