Systems and methods for annealing semiconductor structures

• US 9,129,918 B2
• Filed: 10/30/2013
• Issued: 09/08/2015
• 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, Wang, Chao-Hsiung, Fang, Zi-Wei
• Primary Examiner(s): Lebentritt, Michael
• Assistant Examiner(s): KLEIN, JORDAN M
• Application Number:
  US14/066,756
• Publication Number:
  US 20150118866A1
• Time in Patent Office: 678 Days
• 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. For example, a semiconductor structure is provided. An energy-converting material capable of increasing the semiconductor structure'"'"'s absorption of microwave radiation is provided. A heat reflector is provided between the energy-converting material and the semiconductor structure, the heat reflector being capable of reflecting thermal radiation from the semiconductor structure. Microwave radiation is applied to the energy-converting material and the semiconductor structure to anneal the semiconductor structure for fabricating semiconductor devices.

Claims

1. A method for annealing a semiconductor structure, the method comprising:

providing a semiconductor structure;

providing an energy-converting material capable of increasing the semiconductor structure'"'"'s absorption of microwave radiation;

providing a heat reflector between the energy-converting material and the semiconductor structure, the heat reflector being capable of reflecting thermal radiation from the semiconductor structure; and

applying microwave radiation to the energy-converting material and the semiconductor structure to anneal the semiconductor structure for fabricating semiconductor devices.

2. The method of claim 1, wherein the heat reflector includes a semiconductor wafer.

3. The method of claim 1, wherein the thermal radiation includes infrared radiation.

4. The method of claim 3, wherein the heat reflector has a reflectivity larger than 95% with respect to infrared radiation.

5. The method of claim 1, wherein the heat reflector is approximately transparent to the microwave radiation.

6. The method of claim 1, wherein the energy-converting material is capable of increasing an electric field density associated with the semiconductor structure.

7. The method of claim 6, wherein the energy-converting material increases the electric field density in response to the microwave radiation to further activate dopants through interfacial polarization.

8. The method of claim 6, wherein:

the semiconductor structure includes one or more dopant clusters; and

the semiconductor structure'"'"'s absorption of microwave radiation is increased in response to the increased electric field density so as to dissolve the dopant clusters.

9. The method of claim 1, wherein the heat reflector is disposed at a distance from the semiconductor structure.

10. The method of claim 9, wherein the distance is adjusted to improve the heat reflector'"'"'s reflection of thermal radiation from the semiconductor structure.

11. The method of claim 1, wherein the heat reflector is disposed at a distance from the energy-converting material.

12. The method of claim 1, wherein the heat reflector is formed on the energy-converting material.

13. The method of claim 1, wherein the energy-converting material includes boron-doped silicon germanium, silicon phosphide, titanium, nickel, silicon nitride, silicon dioxide, silicon carbide, n-type doped silicon, or aluminum capped silicon carbide.

14. The method of claim 1, further comprising:

providing a second energy-converting material so that the semiconductor structure is disposed between the heat reflector and the second energy-converting material, the second energy-converting material being capable of increasing the semiconductor structure'"'"'s absorption of microwave radiation.

15. The method of claim 1, wherein the microwave radiation has a frequency within a range of approximately 2 GHz to approximately 10 GHz.

16. The method of claim 1, wherein the energy-converting material has a loss tangent in a range of approximately 0.01 to approximately 2.

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

an energy-converting material configured to increase a semiconductor structure'"'"'s absorption of microwave radiation;

a heat reflector configured to reflect thermal radiation from the semiconductor structure, the heat reflector being disposed between the energy-converting material and the semiconductor structure; and

a microwave-radiation source configured to apply microwave radiation to the energy-converting material and the semiconductor structure to anneal the semiconductor structure for fabricating semiconductor devices.

18. The system of claim 17, wherein the thermal radiation includes infrared radiation.

19. The system of claim 17, wherein the heat reflector includes a semiconductor wafer.

20. The system of claim 17, wherein the heat reflector is approximately transparent to the microwave radiation.