Patent ID: 8440550

Claim:
A method for forming a semiconductor structure, comprising steps of: providing a first wafer comprising a first substrate and a relaxed SiGe layer formed on the first substrate; forming a first strained layer on the relaxed SiGe layer, wherein the first strained layer comprises a first strained SiGe layer with low Ge content; implanting H ions to form an H-ion implanting layer below the first strained layer; flipping the first wafer and the first strained layer and bonding the first strained layer to a second wafer, wherein the second wafer comprises a second substrate and an insulation layer formed on the second substrate; stripping the first wafer by annealing; forming a second strained layer with high Ge content on the first strained layer; and forming a third strained layer on the second strained layer, wherein the third strained layer comprises a third strained SiGe layer with low Ge content, wherein the first, second, and third stained layers form a Si—Ge—Si structure.