Systems and methods for annealing semiconductor structures

• US 9,418,871 B2
• Filed: 08/06/2015
• Issued: 08/16/2016
• Est. Priority Date: 10/30/2013
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Tsai, Chun-Hsiung, Fang, Zi-Wei, Wang, Chao-Hsiung
• Primary Examiner(s): Lebentritt, Michael
• Assistant Examiner(s): KLEIN, JORDAN M
• Application Number:
  US14/819,536
• Publication Number:
  US 20150340244A1
• Time in Patent Office: 376 Days
• Field of Search: None
• US Class Current: 1/1
• 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 21/67115 mainly by radiation
• CPC Class Codes: H05B 6/6482 combined with radiant heating, e.g. infrared heating
• CPC Class Codes: H05B 6/6491 combined with the use of susceptors H05B6/80 and subgroups takes precedence
• CPC Class Codes: H05B 6/80 Apparatus for specific applications stoves or ranges F24C7/02
• CPC Class Codes: H05B 6/806 for laboratory use

Abstract

Systems and methods are provided for annealing a semiconductor structure. In one embodiment, the method includes providing an energy-converting structure proximate a semiconductor structure, the energy-converting structure comprising a material having a loss tangent larger than that of the semiconductor structure; providing a heat reflecting structure between the semiconductor structure and the energy-converting structure; and providing microwave radiation to the energy-converting structure and the semiconductor structure. The semiconductor structure may include at least one material selected from the group consisting of boron-doped silicon germanium, silicon phosphide, titanium, nickel, silicon nitride, silicon dioxide, silicon carbide, n-type doped silicon, and aluminum capped silicon carbide. The heat reflecting structure may include a material substantially transparent to microwave radiation and having substantial reflectivity with respect to infrared radiation.

Claims

1. A method, comprising:

providing an energy-converting structure proximate a semiconductor structure, the energy-converting structure comprising a material having a loss tangent larger than that of the semiconductor structure;

providing a heat reflecting structure between the semiconductor structure and the energy-converting structure; and

providing microwave radiation to the energy-converting structure and the semiconductor structure.

2. The method of claim 1, wherein providing the heat reflecting structure comprises providing a heat reflecting structure that includes a material substantially transparent to microwave radiation and having substantial reflectivity with respect to infrared radiation.

3. The method of claim 2, wherein the heat reflecting structure comprises a material having a reflectivity of no less than about 95% with respect to infrared radiation.

4. The method of claim 1, further comprising adjusting a distance between the heat reflecting structure and the semiconductor structure to improve an infrared radiation reflection to the semiconductor structure.

5. The method of claim 1, wherein providing the heat reflecting structure comprises forming the heat reflecting structure on the energy-converting structure.

6. The method of claim 5, wherein forming the heat reflecting structure on the energy-converting structure comprises epitaxially growing the heat reflecting structure on the energy-converting structure.

7. The method of claim 1, wherein providing the energy-converting structure comprises providing an energy-converting structure having a size larger than the semiconductor structure, thereby facilitating substantially uniform electric field density over the semiconductor structure.

8. The method of claim 1, wherein providing the energy-converting structure comprises providing an energy-converting structure that includes at least one material selected from the group consisting of boron-doped silicon germanium, silicon phosphide, titanium, nickel, silicon nitride, silicon dioxide, silicon carbide, n-type doped silicon, and aluminum capped silicon carbide.

9. The method of claim 8, wherein providing an energy-converting structure comprises providing a first energy-converting structure on a first side of the semiconductor structure.

10. The method of claim 9, wherein providing an energy-converting structure comprises providing a second energy-converting structure on a second side of the semiconductor structure.

11. The method of claim 1, further comprising keeping a temperature of the semiconductor structure within a range of about 300°

C. to about 600°

C. to reduce dopant diffusion.

12. The method of claim 11, wherein keeping the temperature of the semiconductor structure within a range comprises applying the microwave radiation for a time period within a range of about 40 seconds to about 300 seconds.

13. A system for annealing a semiconductor structure, comprising:

a first energy-converting structure arranged proximate the semiconductor structure to be annealed, comprising a material having a loss tangent larger than that of the semiconductor structure;

a heat reflecting structure arranged between the semiconductor structure and the first energy-converting structure; and

a microwave source for generating microwave radiation to anneal the semiconductor structure.

14. The system of claim 13, wherein the heat reflecting structure comprises a material substantially transparent to microwave radiation and having substantial reflectivity with respect to infrared radiation.

15. The system of claim 14, wherein the heat reflecting structure comprises a material having a reflectivity of no less than about 95% with respect to infrared radiation.

16. The system of claim 13, wherein the first energy-converting structure is arranged on a first side of the semiconductor structure, and the system further comprises a second energy-converting structure arranged on a second side of the semiconductor structure.

17. The system of claim 13, wherein the heat reflecting structure is arranged on the first energy-converting structure.

18. The system of claim 13, wherein the heat reflecting structure comprises a selectively doped blank semiconductor layer.

19. The system of claim 13, wherein each of the first and the second energy-converting structures include at least one material selected from the group consisting of boron-doped silicon germanium, silicon phosphide, titanium, nickel, silicon nitride, silicon dioxide, silicon carbide, n-type doped silicon, and aluminum capped silicon carbide.

20. A method of annealing a semiconductor structure using a microwave system, comprising:

arranging an energy-converting structure proximate the semiconductor structure, the semiconductor structure comprising at least one material selected from the group consisting of boron-doped silicon germanium, silicon phosphide, titanium, nickel, silicon nitride, silicon dioxide, silicon carbide, n-type doped silicon, and aluminum capped silicon carbide;

arranging a heat reflecting structure between the semiconductor structure and the energy-converting structure, the heat reflecting structure comprising a material substantially transparent to microwave radiation and having substantial reflectivity with respect to infrared radiation; and

generating microwave radiation with a microwave source to anneal the semiconductor structure.