Semiconductor on insulator structure made using radiation annealing

• US 20070281172A1
• Filed: 03/21/2007
• Published: 12/06/2007
• Est. Priority Date: 05/31/2006
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Couillard, James Gregory, Lehuede, Philippe, Vallon, Sophie A.
• Granted Patent: US 7,579,654 B2
• Time in Patent Office: Days
• US Class Current: 428/446
• CPC Class Codes: G02F 2202/09 inorganic glass
• CPC Class Codes: G02F 2202/104 poly-Si
• CPC Class Codes: H01L 21/268 using electromagnetic radiation, e.g. laser radiation
• CPC Class Codes: H01L 21/302 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
• CPC Class Codes: H01L 21/324 Thermal treatment for modifying the properties of semiconductor bodies, e.g. annealing, sintering H01L21/20 - H01L21/288 and H01L21/302 - H01L21/322 take precedence
• CPC Class Codes: H01L 21/3247 for altering the shape, e.g. smoothing the surface
• CPC Class Codes: H01L 21/67115 mainly by radiation
• CPC Class Codes: H01L 21/7624 using semiconductor on insulator [SOI] technology H01L21/76297 takes precedence; manufacture of integrated circuits on insulating substrates H01L21/84; silicon on sapphire [SOS] technology H01L21/86
• CPC Class Codes: H01L 21/76254 with separation/delamination along an ion implanted layer, e.g. Smart-cut, Unibond

Abstract

Systems and methods for and products of a semiconductor-on-insulator (SOI) structure including subjecting at least one unfinished surface to a laser annealing process. Production of the SOI structure further may include subjecting an implantation surface of a donor semiconductor wafer to an ion implantation process to create an exfoliation layer in the donor semiconductor wafer; bonding the implantation surface of the exfoliation layer to an insulator substrate; separating the exfoliation layer from the donor semiconductor wafer, thereby exposing at least one cleaved surface; and subjecting the at least one cleaved surface to the laser annealing process.

Claims

1. A method of forming a semiconductor-on-insulator structure, comprising:

subjecting an at least one unfinished surface of a crystalline layer to a radiation annealing process.

2. The method of claim 1, wherein the radiation annealing process includes subjecting the at least one unfinished surface to microwave radiation.

3. The method of claim 1, wherein the radiation annealing process comprises a laser annealing process.

4. The method of claim 1, further comprising:

subjecting an implantation surface of a crystalline donor semiconductor wafer to an ion implantation process to create an exfoliation layer of the donor semiconductor wafer;

bonding the implantation surface of the exfoliation layer to an insulator substrate; and

separating the exfoliation layer from the donor semiconductor wafer, thereby exposing at least one cleaved surface;

wherein the subjecting an at least one unfinished surface to a radiation annealing process follows the separating the exfoliation layer, and wherein the at least one unfinished surface comprises the at least one cleaved surface.

5. The method of claim 4, wherein the at least one cleaved surface includes a first cleaved surface of the donor semiconductor wafer and a second cleaved surface of the exfoliation layer.

6. The method of claim 5, wherein the radiation annealing process is applied to at least the second cleaved surface of the exfoliation layer.

7. The method of claim 5, wherein the radiation annealing process is applied to at least the first cleaved surface of the donor semiconductor wafer.

8. The method of claim 4, wherein the radiation annealing process includes subjecting the at least one unfinished surface to laser radiation.

9. The method of claim 8, wherein the at least one unfinished surface comprises crystalline silicon.

10. The method of claim 8, wherein the subjecting the at least one unfinished surface to laser radiation comprises:

first subjecting the at least one unfinished surface to a first laser radiation, and afterwards subjecting the at least one unfinished surface to a second laser radiation that has a higher intensity than the first laser radiation.

11. The method of claim 1, wherein prior to the step of subjecting an at least one unfinished surface of a crystalline layer to a radiation annealing process, the whole crystalline layer is heated to an elevated temperature from 100°

C. to T_sp-100°

C., where T_sp is the strain point of a glass contained in the semiconductor-on-insulator structure, or the melting point of the component in the semiconductor-on-insulator structure with the lowest melting temperature.

12. The method of claim 1, wherein prior to subjecting the at least one unfinished surface of a crystalline layer to the radiation annealing process, the at least one unfinished surface is cleaned and/or a surface layer of oxide is removed.

13. The method of claim 12, wherein the laser radiation has an energy level sufficient to temporarily melt at least part of the at least one unfinished surface.

14. The method of claim 4, wherein the step of bonding includes:

heating at least one of the insulator substrate and the donor semiconductor wafer;

bringing the insulator substrate into direct or indirect contact with the exfoliation layer of the donor semiconductor wafer; and

applying a voltage potential across the insulator substrate and the donor semiconductor wafer to induce the bond.

15. The method of claim 4, wherein the donor semiconductor wafer is selected from:

silicon (Si), germanium-silicon (SiGe), silicon carbide (SiC), germanium (Ge), gallium arsenide (GaAs), gallium phosphide (GaP), and indium phosphide (InP).

16. The method of claim 4, wherein the donor semiconductor wafer includes a substantially single-crystal donor semiconductor wafer, and the separated layer is formed substantially from the single-crystal donor semiconductor wafer material.

17. The method of claim 4, wherein the donor semiconductor wafer includes a donor semiconductor wafer and an epitaxial semiconductor layer disposed on the donor semiconductor wafer, and the separated layer is formed substantially from the epitaxial semiconductor layer.

18. A semiconductor-on-insulator structure, comprising:

an insulator structure; and

a semiconductor layer bonded on the insulator structure, wherein the semiconductor layer comprises a radiation annealed surface.

19. The semiconductor-on-insulator structure of claim 18, wherein the radiation annealed surface comprises a laser annealed surface.

20. The semiconductor-on-insulator structure of claim 18, wherein the radiation annealed surface comprises a microwave annealed surface.

21. The semiconductor-on-insulator structure of claim 18, wherein the semiconductor layer comprises an underside bonded to the insulator structure, and wherein the radiation annealed surface is opposite to the underside.

22. The semiconductor-on-insulator structure of claim 18, wherein the insulator structure comprises an insulator substrate, and wherein the semiconductor layer comprises crystalline silicon.

23. A system for the formation of semiconductor-on-insulator structures, the system comprising:

a semiconductor-on-insulator handling assembly, and

a radiation annealing assembly,

wherein the radiation annealing assembly comprises a radiation source for irradiation of semiconductor-on-insulator structures being handled by the semiconductor-on-insulator handling assembly.

24. The system of claim 23, wherein the radiation source comprises a laser.

25. The system of claim 24, wherein the laser comprises an excimer laser.

26. The system of claim 25, wherein the excimer laser is a xenon chloride (XeCl) laser.

27. The system of claim 23, wherein the radiation source comprises a microwave emitter.

28. The system of claim 23, wherein the radiation annealing assembly operates in a vacuum.

29. The system of claim 23, wherein the radiation annealing assembly operates in a controlled atmosphere.