CMP polishing head design for improving removal rate uniformity
US11529712B2 · kind B2 · utility
1Cited by
12References
17Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 19, 2018 |
| Grant date | Dec 20, 2022 |
| Priority date | — |
| Expiry date | Dec 23, 2040 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB24B37/32
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
An apparatus for performing chemical mechanical polish on a wafer includes a polishing head that includes a retaining ring. The polishing head is configured to hold the wafer in the retaining ring. The retaining ring includes a first ring having a first hardness, and a second ring encircled by the first ring, wherein the second ring has a second hardness smaller than the first hardness.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.