System and method for polishing substrate

Patent metadata

Field	Value
Publication number	US-10272540-B2
Application number	US-201715596160-A
Country	US
Kind code	B2
Filing date	May 16, 2017
Priority date	May 29, 2015
Publication date	Apr 30, 2019
Grant date	Apr 30, 2019

Abstract

Polishing systems and methods for polishing a substrate are provided. The method includes polishing a substrate using a polishing pad and monitoring a thickness of the polishing pad. The monitoring of the thickness of the polishing pad is performed by detecting an eddy current generated from a conductor element below a bottom surface of the polishing pad. The method also includes replacing the polishing pad with a second polishing pad if the thickness of the polishing pad is smaller than a predetermined value.

First claim

What is claimed is:

1. A method for performing a polishing process, comprising:
polishing a substrate using a polishing pad;
monitoring a thickness of the polishing pad, wherein the monitoring of the thickness of the polishing pad is performed by detecting an eddy current generated from a conductor element dispersed in the polishing pad, wherein the conductor element comprises conductive fibers, conductive particles, or a combination thereof; and
replacing the polishing pad with a second polishing pad if the eddy current is smaller than a predetermined value.

2. The method for performing a polishing process as claimed in claim 1 , wherein the monitoring of the thickness of the polishing pad is performed during the polishing of the substrate.

3. The method for performing a polishing process as claimed in claim 1 , further comprising:
conditioning the polishing pad using a conditioning disc; and
reducing a force applied to the polishing pad from the conditioning disc if the eddy current is smaller than a second predetermined value, wherein the second predetermined value is greater than the predetermined value.

4. The method for performing a polishing process as claimed in claim 1 , wherein the eddy current is detected by a thickness sensing assembly, wherein at least a portion of the polishing pad is positioned between the thickness sensing assembly and the conductor element.

5. The method for performing a polishing process as claimed in claim 1 , wherein the eddy current is detected by a thickness sensing assembly, wherein the thickness sensing assembly is positioned outside of the polishing pad.

6. The method for performing a polishing process as claimed in claim 1 , wherein the eddy current is detected by a thickness sensing assembly, wherein the thickness sensing assembly is positioned below the polishing pad.

7. The method for performing a polishing process as claimed in claim 1 , wherein the eddy current is detected by a thickness sensing assembly, wherein the thickness sensing assembly is positioned in a platen on which the polishing pad is placed.

8. The method for performing a polishing process as claimed in claim 1 , wherein the conductor element comprises carbon particles, carbon fibers, or a combination thereof.

9. A method for performing a chemical mechanical polishing (CMP) process, comprising:
polishing a substrate using a polishing pad;
providing a slurry between the substrate and the polishing pad;
conditioning the polishing pad;
monitoring a thickness of the polishing pad, wherein the monitoring of the thickness of the polishing pad is performed by detecting an eddy current generated from a conductor element dispersed in an upper portion of the polishing pad, wherein the conductor element comprises carbon-containing conductive particles, carbon-containing conductive fibers, or a combination thereof; and
replacing the polishing pad with a second polishing pad if the thickness of the polishing pad is smaller than a predetermined value.

10. The method for performing a CMP process as claimed in claim 9 , wherein the monitoring of the thickness of the polishing pad is performed during the polishing of the substrate.

11. The method for performing a CMP process as claimed in claim 9 , wherein the conditioning of the polishing pad is performed during the polishing of the substrate.

12. The method for performing a CMP process as claimed in claim 9 , further comprising reducing a force applied to the polishing pad during the conditioning of the polishing pad if the thickness of the polishing pad is smaller than a second predetermined value, wherein the second predetermined value is greater than the predetermined value.

13. The method for performing a CMP process as claimed in claim 9 , wherein the conductor element is dispersed evenly in the upper portion of the polishing pad.

14. A method for performing a polishing process, comprising:
polishing a substrate using a polishing pad;
monitoring a thickness of the polishing pad during the polishing of the substrate by detecting an eddy current generated from conductor elements positioned under a top surface of the polishing pad, wherein the conductor elements comprises carbon-containing conductive fibers, carbon-containing conductive fibers, or a combination thereof; and
stopping the polishing of the substrate if the thickness of the polishing pad is smaller than a predetermined value.

15. The method for performing a polishing process as claimed in claim 14 , further comprising replacing the polishing pad with a second polishing pad after the polishing of the substrate is stopped.

16. The method for performing a polishing process as claimed in claim 14 , further comprising:
conditioning the polishing pad using a conditioning disc during the polishing of the substrate; and
reducing a force applied to the polishing pad from the conditioning disc if the thickness of the polishing pad is smaller than a second predetermined value, wherein the second predetermined value is greater than the predetermined value.

17. The method for performing a polishing process as claimed in claim 14 , wherein the polishing pad comprises a top pad and a bottom pad, and the conductor elements are positioned between a portion of the top pad and the bottom pad.

18. The method for performing a polishing process as claimed in claim 14 , further comprising reducing a force applied to the polishing pad during a conditioning of the polishing pad if the thickness of the polishing pad is smaller than a second predetermined value, wherein the second predetermined value is greater than the predetermined value.

19. The method for performing a polishing process as claimed in claim 14 , wherein the conductor elements are dispersed in the polishing pad.

20. The method for performing a polishing process as claimed in claim 19 , wherein the conductor elements are dispersed evenly in an upper portion of the polishing pad.

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Lai Jiun-Yu
• Tsai Ying-Hsiu
• Chang Wei-Chen
• Chiou Yi-Ching

Classifications

• B24B37/04 Primary

  designed for working plane surfaces · CPC title

• B24B37/34

  Accessories · CPC title

• B24B37/005

  Control means for lapping machines or devices · CPC title

• B24B53/017

  Devices or means for dressing, cleaning or otherwise conditioning lapping tools · CPC title

• B24B37/042

  operating processes therefor · CPC title