Method for producing a high quality useful layer on a substrate
A method for producing a high quality useful layer of semiconductor material on a substrate. The method includes 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. The implanting step is conducted to minimize low-frequency roughness at the weakened zone. Next, the method includes bonding a support substrate to the face of the donor substrate, and detaching the useful layer from the donor substrate along the weakened zone. A structure is thus formed that includes the useful layer on the support substrate with the useful layer presenting a surface for further processing. The technique also includes thermally treating the structure to minimize high-frequency roughness of the surface of the useful layer. The result is a surface having sufficient smoothness so that chemical mechanical polishing (CMP) is not needed.
1 . 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 to minimize low-frequency roughness of the useful layer surface; and
thermally treating the structure to minimize high-frequency roughness of the useful layer surface to thus provide the surface having sufficient smoothness to be suitable for use in microelectronic or optoelectronic applications without conducting a chemical mechanical polishing of the useful layer surface.
2 . The method of claim 1 , wherein the different atomic species are implanted so that the detachment of the useful layer at the weakened zone provides the useful layer surface with a low-frequency roughness of less than about 5 Å.
3 . The method of claim 2 , wherein the low-frequency roughness if measured over spatial periods of substantially between 3 and 15 μm.
4 . The method of claim 1 , further comprising conducting at least one of a simple or stabilized oxidation process on the useful layer surface after the thermal treatment, wherein a chemical mechanical polishing step is not conducted prior to the thermal treatment and the oxidation process.
5 . The method of claims 1 , wherein the at least two different atomic species comprises helium species and hydrogen species, and implanting comprises sequentially implanting the helium species and then the hydrogen species.
6 . The method of claim 1 , wherein the thermal treatment is a rapid thermal annealing process carried out at a temperature of between about 800° C. and 1400° C.
7 . The method of claim 6 , wherein the rapid thermal annealing process is conducted in an atmosphere comprising pure argon or hydrogen or a mixture thereof.
8 . The method of claim 1 , which further comprises conducting at least one stabilized oxidation process on the structure.
9 . The method of claim 8 , wherein the stabilized oxidation process comprises successive implementations of an oxidation operation, an annealing operation, and a deoxidation operation.
10 . The method of claim 9 , wherein the annealing operation comprises conducting the annealing operation for about two hours at a temperature of about 1100° C.
11 . The method of claim 8 , which further comprises conducting a rapid thermal annealing process on the structure prior to or after the stabilized oxidation process.
12 . The method of claim 8 , which further comprises conducting a plurality of both rapid thermal annealing and stabilized oxidation processes on the structure.
13 . The method of claim 1 , which further comprises at least one simple oxidation operation including an oxidation operation followed by a deoxidation operation of the structure.
14 . The method of claim 13 , which further comprises conducting a rapid thermal annealing process on the useful layer surface.
15 . A method for producing a high quality useful layer of semiconductor material on a substrate, which comprises:
sequentially implanting at least helium species and then hydrogen 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 to minimize low-frequency roughness of the useful layer surface; 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.
16 . The method of claim 15 , wherein the helium species is implanted at a dose of between about 0.5×10 16 cm −2 and about 1.5×10 16 cm −2 .
17 . The method of claim 16 , wherein the helium species is implanted at a dose of about 0.9×10 16 cm −2 or less.
18 . The method of claim 17 , wherein the hydrogen species is implanted at a dose of between about 0.5×10 16 cm −2 and about 0.9×10 16 cm −2 .
19 . The method of claim 15 , wherein the hydrogen species is implanted at a dose of between about 0.5×10 16 cm −2 and about 2.5×10 16 cm −2 .