| 摘要 |
The invention relates to a composite support (10) intended to receive a transferred layer (20) made of a material chosen from crystalline materials, so that the assembly forms a substrate (30) for epitaxy, characterized in that it has a longitudinal plane of symmetry (100) parallel to its principal surfaces and in that it consists of: . a central first layer (1) having a first thermal expansion coefficient at a defined temperature T, the said layer extending transversely on either side of the plane of symmetry; and . at least one pair of lateral layers (2, 2', 3, 3'), the layers of each pair having, facing each other: -arrangements in the composite support (10) that are substantially symmetrical with respect to the plane of symmetry; - second thermal expansion coefficients at the temperature T that are substantially identical to each other; and - thicknesses substantially identical to each other; and in that the materials constituting the layers of the composite support (10) are chosen in such a way that the composite support (10) has an overall thermal expansion coefficient at the temperature T close to the thermal expansion coefficient of the material of the transferred layer (20) at the temperature T. The invention also relates to processes for forming a useful layer on the said composite support and to structures comprising substrates for epitaxy. |
