| 摘要 |
A method of fabricating a semiconductor structure. According to one aspect of the invention, on a first semiconductor substrate, a first compositionally graded Si<SUB>1-x</SUB>Ge<SUB>x </SUB>buffer is deposited where the Ge composition x is increasing from about zero to a value less than about 20%. Then a first etch-stop Si<SUB>1-y</SUB>Ge<SUB>y </SUB>layer is deposited where the Ge composition y is larger than about 20% so that the layer is an effective etch-stop. A second etch-stop layer of strained Si is then grown. The deposited layer is bonded to a second substrate. After that the first substrate is removed to release said first etch-stop Si<SUB>1-y</SUB>Ge<SUB>y </SUB>layer. The remaining structure is then removed in another step to release the second etch-stop layer. According to another aspect of the invention, a semiconductor structure is provided. The structure has a layer in which semiconductor devices are to be formed. The semiconductor structure includes a substrate, an insulating layer, a relaxed SiGe layer where the Ge composition is larger than approximately 15%, and a device layer selected from a group consisting of, but not limited to, strained-Si, relaxed Si<SUB>1-y</SUB>Ge<SUB>y </SUB>layer, strained S<SUB>1-z</SUB>Ge<SUB>z </SUB>layer, Ge, GaAs, III-V materials, and II-VI materials, where Ge compositions y and z are values between 0 and 1. |
