Process for manufacturing a composite structure comprising a single-crystal thin layer on a support substrate

A method for producing a composite structure comprises providing a donor substrate including a single-crystal material, and a support substrate having a first alignment pattern on a face or edge of the support substrate. A heat treatment is applied at least to the donor substrate to bring about a surface reorganization on at least one face of the donor substrate. The surface reorganization results in formation of first steps of nanometric amplitude, which are parallel to a first main axis. The donor substrate and the support substrate are optically aligned, to better than ±0.1° between a locating mark indicating the first main axis on the donor substrate and at least one alignment pattern of the support substrate. The donor substrate and the support substrate are then assembled together, and a thin layer is transferred from the donor substrate onto the support substrate.