Method for cleaning a plasma chamber

• US 20040103914A1
• Filed: 05/22/2003
• Published: 06/03/2004
• Est. Priority Date: 12/02/2002
• Status: Active Grant

• Current Assignee: AU Optronics Corporation
• Original Assignee: AU Optronics Corporation
• Inventors: Wu, Shu-Feng, Cheng, Chao-Yun, Chuang, Chih-Chung, Kuo, Shin-Jien
• Granted Patent: US 6,926,014 B2
• Time in Patent Office: Days
• US Class Current: 134/1.1
• CPC Class Codes: B08B 7/0035 by radiant energy, e.g. UV, laser, light beam or the like
• CPC Class Codes: H01J 37/32862 In situ cleaning of vessels and/or internal parts
• CPC Class Codes: Y10S 134/902 Semiconductor wafer
• CPC Class Codes: Y10S 438/905 Cleaning of reaction chamber

Abstract

A method for cleaning a plasma chamber after metal etching. First, a substrate having a metal layer thereon is placed in a plasma chamber. Next, the metal layer is etched. Finally, the substrate is removed from the plasma chamber to perform a dry cleaning which includes the following steps. First, the inner wall of the plasma chamber is cleaned by plasma etching using oxygen as a process gas. Next, the top and bottom electrode plates in the plasma chamber are cleaned by plasma etching using chlorine and boron chloride as process gases. Next, the inner wall of the plasma chamber is cleaned again by plasma etching using sulfur hexafluoride and oxygen as process gases. Finally, oxygen and helium used as purging gases are injected into the plasma chamber and exhausted from therein.

Claims

1. A method for cleaning a plasma chamber, comprising the steps of:

performing a first plasma etching in the plasma chamber to clean the inner wall of the plasma chamber;

performing a second plasma etching in the plasma chamber to clean the top and bottom of the electrode plates in the plasma chamber; and

performing a third plasma etching in the plasma chamber to clean the inner wall of the plasma chamber.

2. The method as claimed in claim 1, further comprising injecting a purging gas into the plasma chamber and exhausting from therein.

3. The method as claimed in claim 2, wherein the purging gas is injected for about 20˜

40 sec.

4. The method as claimed in claim 2, wherein the purging gas is a mixture of oxygen and helium and the flow rates of oxygen and helium are about 800˜

1000 sccm, respectively.

5. The method as claimed in claim 1, wherein the first plasma etching is performed using oxygen as a process gas and the flow rate of oxygen is about 600˜

800 sccm.

6. The method as claimed in claim 5, wherein the first plasma etching is performed under a pressure of about 3˜

10 mTorr.

7. The method as claimed in claim 5, wherein the first plasma etching is performed under a pressure of about 15˜

40 mTorr.

8. The method as claimed in claim 1, wherein the second plasma etching is performed using chlorine and boron chloride as process gases and the flow rate of chlorine is about 100˜

500 sccm and that of boron chloride is about 50˜

150 sccm.

9. The method as claimed in claim 8, wherein the second plasma etching is performed under a pressure of about 3˜

6 mTorr.

10. The method as claimed in claim 1, wherein the third plasma etching is performed using sulfur hexafluoride and oxygen as process gases and the flow rates of sulfur hexafluoride and oxygen are about 600˜

800 sccm, respectively.

11. The method as claimed in claim 10, wherein the third plasma etching is performed under a pressure of about 50˜

70 mTorr.

12. A method for cleaning a plasma chamber after metal etching, comprising the steps of:

placing a substrate having a metal layer thereon in a plasma chamber;

etching the metal layer;

removing the substrate from the plasma chamber; and

performing a dry cleaning in the plasma chamber, wherein the dry cleaning comprises;

performing a first plasma etching in the plasma chamber to clean the inner wall of the plasma chamber;

performing a second plasma etching in the plasma chamber to clean the top and bottom of the electrode plates in the plasma chamber; and

performing a third plasma etching in the plasma chamber to clean the inner wall of the plasma chamber.

13. The method as claimed in claim 12, wherein the dry cleaning further comprises injecting a purging gas into the plasma chamber and exhausting from therein.

14. The method as claimed in claim 13, wherein the purging gas is injected for between 20˜

40 seconds.

15. The method as claimed in claim 14, wherein the purging gas is a mixture of oxygen and helium and the flow rates of oxygen and helium is between 800˜

1000 sccm, respectively.

16. The method as claimed in claim 12, wherein the metal layer is a molybdenum-aluminum-neodymium (MoAlNd) alloy layer.

17. The method as claimed in claim 16, wherein the first plasma etching is performed using oxygen as a process gas and the flow rate of oxygen is between 600˜

800 sccm.

18. The method as claimed in claim 17, wherein the first plasma etching is performed under a first pressure between 3˜

10 mTorr.

19. The method as claimed in claim 17, wherein the first plasma etching is performed under a second pressure between 15˜

40 mTorr.

20. The method as claimed in claim 16, wherein the second plasma etching is performed using chlorine and boron chloride as process gases and the flow rate of chlorine is between 100˜

500 sccm and that of boron chloride is between 50˜

150 sccm.

21. The method as claimed in claim 20, wherein the second plasma etching is performed under a pressure between 3˜

6 mTorr.

22. The method as claimed in claim 16, wherein the third plasma etching is performed using sulfur hexafluoride and oxygen as process gases and the flow rates of sulfur hexafluoride and oxygen are between 600˜

800 sccm, respectively.

23. The method as claimed in claim 22, wherein the third plasma etching is performed under a pressure between 50˜

70 mTorr.