CHEMICAL MECHANICAL POLISHING APPARATUS HAVING SCRAPING FIXTURE

• US 20200130132A1
• Filed: 12/12/2018
• Published: 04/30/2020
• Est. Priority Date: 10/24/2018
• Status: Active Grant

• Current Assignee: Yangtze Memory Technologies Co., Ltd. (Yangtze River Storage Technology Holdings Co. , Ltd.)
• Original Assignee: Yangtze Memory Technologies Co., Ltd. (Yangtze River Storage Technology Holdings Co. , Ltd.)
• Inventors: Gao, Lin, Jiang, Yangbo, Wang, Guangyi, Yang, Juncheng
• Granted Patent: US 11,396,080 B2
• Time in Patent Office: Days
• CPC Class Codes: B24B 37/107 in a rotary movement only, about an axis being stationary during lapping
• CPC Class Codes: B24B 37/20 Lapping pads for working plane surfaces
• CPC Class Codes: B24B 37/32 Retaining rings
• CPC Class Codes: H01L 21/67092 Apparatus for mechanical treatment or grinding or cutting, see the relevant groups in subclasses B24B or B28D

Abstract

Embodiments of apparatus and method for chemical mechanical polishing (CMP) are disclosed. In an example, an apparatus for CMP includes a platen, a slurry supply, and at least one scraping fixture. The platen is configured to rotate a pad thereon about a central axis of the pad. The slurry supply is configured to supply a slurry onto the pad while the pad rotates. The at least one scraping fixture is configured to scrape the slurry off the pad when the slurry travels a distance between the slurry supply and the at least one scraping fixture in a circumferential direction of the pad as the pad rotates.

Claims

1. An apparatus for chemical mechanical polishing (CMP), comprising:

a platen configured to rotate a pad thereon about a central axis of the pad;

a slurry supply configured to supply a slurry onto the pad while the pad rotates; and

at least one scraping fixture configured to scrape the slurry off the pad when the slurry travels a distance between the slurry supply and the at least one scraping fixture in a circumferential direction of the pad as the pad rotates.

2. The apparatus of claim 1, wherein the at least one scraping fixture comprises a scraper including a lower end abutting a top surface of the pad while the pad rotates.

3. The apparatus of claim 2, wherein the lower end of the scraper is made of polymer.

4. The apparatus of claim 2, wherein the scraper is configured to apply a pressure against the top surface of the pad to stop the slurry from rotating with the pad, such that the slurry flows off the pad along the scraper.

5. The apparatus of claim 1, wherein the at least one scraping fixture comprises a conductor electrically coupled to the pad to ground the pad while the pad rotates.

6. The apparatus of claim 5, wherein the conductor of the at least one scraping fixture is electrically coupled to the slurry supply.

7. The apparatus of claim 1, wherein the at least one scraping fixture is attached to the slurry supply.

8. The apparatus of claim 1, wherein the at least one scraping fixture comprises a plurality of scraping fixtures spaced apart along the circumferential direction of the pad.

9. The apparatus of claim 1, further comprising a carrier configured to hold a wafer on the pad between the slurry supply and the at least one scraping fixture in the circumferential direction of the pad while the pad rotates.

10. The apparatus of claim 9, wherein the slurry is scraped off the pad after being used for polishing the wafer.

11. An apparatus for chemical mechanical polishing (CMP), comprising:

a platen configured to rotate a pad thereon about a central axis of the pad;

a slurry supply configured to supply a fresh slurry onto the pad while the pad rotates;

a carrier configured to hold a wafer on the pad while the pad rotates, wherein the fresh slurry flows between the wafer and the pad as the pad rotates and thereby becomes a used slurry; and

at least one scraping fixture configured to scrape the used slurry off the pad while the pad rotates.

12. The apparatus of claim 11, wherein the at least one scraping comprises a scraper including a lower end abutting a top surface of the pad while the pad rotates.

13. The apparatus of claim 12, wherein the lower end of the scraper is made of polymer.

14. The apparatus of claim 12, wherein the scraper is configured to apply a pressure against the top surface of the pad to stop the used slurry from rotating with the pad, such that the used slurry flows off the pad along the scraper.

15. The apparatus of claim 11, wherein the at least one scraping fixture comprises a conductor electrically coupled to the pad to ground the pad while the pad rotates.

16. The apparatus of claim 15, wherein the conductor of the at least one scraping fixture is electrically coupled to the slurry supply.

17. The apparatus of claim 11, wherein the at least one scraping fixture is attached to the slurry supply.

18. The apparatus of claim 11, wherein the at least one scraping fixture comprises a plurality of scraping fixtures spaced apart along the circumferential direction of the pad.

19. The apparatus of claim 11, wherein the at least one scraping fixture is disposed between the carrier and the slurry supply in a circumferential direction of the pad as the pad rotates.

20. A method for chemical mechanical polishing (CMP), comprising:

rotating a pad about a central axis of the pad;

supplying a fresh slurry onto the pad while the pad rotates;

holding a wafer on the pad while the pad rotates;

polishing the wafer by the fresh slurry when the fresh slurry flows between the wafer and the pad as the pad rotates, thereby becoming a used slurry; and

scraping, by a scraping fixture, the used slurry off the pad while the pad rotates.