Patent ID: 7081399

Claim:
A method for producing a high quality useful layer of semiconductor material on a substrate, which comprises: implanting at least two different atomic species into a face of a donor substrate to a controlled mean implantation depth to form a weakened zone therein and to define a useful layer; bonding a support substrate to the face of the donor substrate; detaching the useful layer from the donor substrate along the weakened zone to form a structure that includes the useful layer on the support substrate with the useful layer presenting a useful layer surface for further processing, wherein the different atomic species are implanted so that the useful layer surface is provided with a low-frequency roughness of less than about 5 Å measured over a sweep area of about 40×40 μm 2 after the detachment of the useful layer at the weakened zone without chemical mechanical polishing; and thermally treating the structure to minimize high-frequency roughness of the useful layer surface to thus provide sufficient smoothness so that chemical mechanical polishing of the useful layer surface is not required.