Multi-fluid polishing process

• US 6,572,453 B1
• Filed: 05/18/2000
• Issued: 06/03/2003
• Est. Priority Date: 09/29/1998
• Status: Expired due to Fees

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Bennett, Doyle E., Redeker, Fred C., Brown, Brian J., Tsai, Stan D., Wijekoon, Kapila, Wang, Yuchun, Chandrachood, Madhavi
• Primary Examiner(s): Hail, III, Joseph J.
• Assistant Examiner(s): Thomas, David B.
• Application Number:
  US09/575,218
• Time in Patent Office: 1,111 Days
• Field of Search: 451/56, 451/285, 451/287, 451/443, 451/444
• US Class Current: 451/56
• CPC Class Codes: B08B 1/32 using rotary cleaning members
• CPC Class Codes: B24B 37/04 designed for working plane surfaces
• CPC Class Codes: B24B 57/02 for feeding of fluid, sprayed, pulverised, or liquefied grinding, polishing or lapping agents
• CPC Class Codes: C11D 2111/22 Electronic devices, e.g. PCBs or semiconductors
• CPC Class Codes: C11D 7/06 Hydroxides
• CPC Class Codes: C11D 7/08 Acids
• CPC Class Codes: C11D 7/265 Carboxylic acids or salts thereof
• CPC Class Codes: C11D 7/3209 Amines or imines with one to four nitrogen atoms; Quaternized amines
• CPC Class Codes: H01L 21/3212 by chemical mechanical polishing [CMP]

Abstract

A polishing method is provided which simultaneously supplies both a polishing fluid and a conditioning fluid to a polishing pad, while a substrate is in moving contact with the polishing pad.

Claims

1. A method of polishing a substrate comprising:

placing a substrate, having a material to be polished, in contact with a polishing pad;

generating relative movement between the substrate and the polishing pad, while the substrate and polishing pad are in contact, and

supplying a polishing chemical and a conditioning fluid to the polishing pad while the polishing pad and substrate are in moving contact, wherein the conditioning fluid etches polishing by products comprising the material.

2. The method of claim 1 further comprising conditioning the polishing pad with an abrasive conditioning surface while supplying the polishing chemical and the conditioning fluid to the polishing pad.

3. The method of claim 1 wherein the material to be polished is one that, absent the conditioning fluid, would build up on the polishing pad, and wherein the conditioning fluid is one that prevents such build up.

4. The method of claim 3 further comprising conditioning the polishing pad with an abrasive conditioning surface while supplying the polishing chemical and the conditioning fluid to the polishing pad.

5. The method of claim 3 wherein the conditioning fluid is diluted with deionized water.

6. The method of claim 5 further comprising conditioning the polishing pad with an abrasive conditioning surface while supplying the polishing chemical and the conditioning fluid to the polishing pad.

7. The method of claim 1 wherein the material to be polished is copper.

8. The method of claim 7 further comprising conditioning the polishing pad with an abrasive conditioning surface while supplying the polishing chemical and the conditioning fluid to the polishing pad.

9. The method of claim 7 wherein the conditioning fluid comprises citric acid and ammonium hydroxide.

10. The method of claim 9 further comprising conditioning the polishing pad with an abrasive conditioning surface while supplying the polishing chemical and the conditioning fluid to the polishing pad.

11. The method of claim 1 wherein the polishing chemical is diluted with an oxidizing agent.

12. The method of claim 7 wherein the polishing by products comprise copper oxide.

13. The method of claim 9 wherein the polishing by products comprise copper oxide.

14. The method of claim 1 wherein the polishing by products comprise copper compounds.

15. The method of claim 1 wherein the conditioning fluid comprises a carboxylic salt.

16. The method of claim 1 wherein the conditioning fluid comprises an ammonium compound.

17. The method of claim 2 wherein the conditioning fluid comprises a carboxylic salt.

18. The method of claim 2 wherein the conditioning fluid comprises an ammonium compound.

19. The method of claim 1 wherein the conditioning fluid comprises citric acid and ammonium hydroxide.

20. The method of claim 2 wherein the conditioning fluid comprises citric acid and ammonium hydroxide.