Systems and methods for reducing copper contamination due to substrate processing chambers with components made of alloys including copper

• US 9,397,011 B1
• Filed: 04/13/2015
• Issued: 07/19/2016
• Est. Priority Date: 04/13/2015
• Status: Active Grant

• Current Assignee: Lam Research Corporation
• Original Assignee: Lam Research Corporation
• Inventors: Ting, Yuk-Hong, Fang, Haoquan, Cheung, David
• Primary Examiner(s): Choudhry, Mohammad
• Application Number:
  US14/684,870
• Time in Patent Office: 463 Days
• US Class Current: 1/1
• CPC Class Codes: C23C 16/4404 Coatings or surface treatment on the inside of the reaction chamber or on parts thereof
• CPC Class Codes: C23C 16/4408 by purging residual gases from the reaction chamber or gas lines
• CPC Class Codes: H01J 37/32853 Hygiene
• CPC Class Codes: H01J 37/32862 In situ cleaning of vessels and/or internal parts
• CPC Class Codes: H01J 37/32871 Means for trapping or directing unwanted particles
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/31138 by dry-etching

Abstract

Systems and methods for reducing copper contamination in a substrate processing system include performing a plasma process on a substrate in a processing chamber of a substrate processing system. A component is located in the processing chamber and is made of an alloy including copper. The plasma process uses a process gas mixture including molecular hydrogen. Prior to performing the plasma process on the substrate and before the substrate is arranged in the processing chamber, the component is conditioned in the processing chamber using a conditioning plasma process that includes a process gas mixture including molecular oxygen and forming gas.

Claims

1. A method for reducing copper contamination in a substrate processing system, comprising:

performing a plasma process on a substrate in a processing chamber of a substrate processing system,

wherein a component located in the processing chamber is made of an alloy including copper,

wherein the plasma process uses a process gas mixture including molecular hydrogen; and

prior to performing the plasma process on the substrate and before the substrate is arranged in the processing chamber, conditioning the component in the processing chamber using a conditioning plasma process that includes a process gas mixture including molecular oxygen and forming gas.

2. The method of claim 1, wherein the alloy includes aluminum.

3. The method of claim 1, wherein the alloy comprises 6061 aluminum alloy.

4. The method of claim 1, wherein the process gas mixture includes forming gas.

5. The method of claim 4, wherein the forming gas includes 4% molecular hydrogen and 96% molecular nitrogen.

6. The method of claim 1, further comprising arranging a dummy substrate on a substrate support in the processing chamber during the conditioning plasma process.

7. The method of claim 1, wherein the substrate includes a semiconductor wafer.

8. The method of claim 1, wherein the plasma process includes a photoresist strip process.

9. The method of claim 1, wherein copper contamination in the processing chamber before the conditioning plasma process as compared to copper contamination after the conditioning plasma process is reduced by a factor of 10.

10. The method of claim 1, wherein the conditioning plasma process includes N plasma processing cycles each including a plasma ON time, and wherein N is an integer greater than one.

11. A substrate processing system, comprising:

a processing chamber;

a component located in the processing chamber that is made of an alloy including copper;

a plasma generator configured to generate plasma in the processing chamber;

a gas delivery system configured to selectively deliver forming gas, molecular oxygen and/or molecular hydrogen to the processing chamber; and

a controller that communicates with the gas delivery system and the plasma generator, and that is configured to;

prior to performing a plasma process on a substrate in the processing chamber using a process gas mixture including molecular hydrogen and before the substrate is arranged in the processing chamber, condition the component in the processing chamber using a conditioning plasma process that includes a process gas mixture including the molecular oxygen and the forming gas; and

perform the plasma process on the substrate.

12. The substrate processing system of claim 11, wherein the alloy includes aluminum.

13. The substrate processing system of claim 11, wherein the alloy comprises 6061 aluminum alloy.

14. The substrate processing system of claim 11, wherein the process gas mixture includes forming gas.

15. The substrate processing system of claim 14, wherein the forming gas includes 4% molecular hydrogen and 96% molecular nitrogen.

16. The substrate processing system of claim 11, wherein the controller is configured to arrange a dummy substrate on a substrate support in the processing chamber during the conditioning plasma process.

17. The substrate processing system of claim 11, wherein the substrate includes a semiconductor wafer.

18. The substrate processing system of claim 11, wherein the plasma process includes a photoresist strip process.

19. The substrate processing system of claim 11, wherein copper contamination in the processing chamber before the conditioning plasma process as compared to copper contamination after the conditioning plasma process is reduced by a factor of 10.

20. The substrate processing system of claim 11, wherein the conditioning plasma process includes N plasma processing cycles each including a plasma ON time, and wherein N is an integer greater than one.