Substrate retaining ring for CMP
US8393936B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 24, 2009 |
| Grant date | Mar 12, 2013 |
| Priority date | — |
| Expiry date | Mar 28, 2031 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB24B37/32
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
The edge effect or variation in polishing edge profile on a substrate undergoing CMP is reduced by structuring a retaining ring, housed in a carrier head for retaining the substrate, such that the polishing edge profile shifts back and forth with respect to the center of the substrate. Embodiments include structuring the retaining ring such that the width between inner and outer surfaces varies by an amount sufficient to compensate for polishing edge profile variation. Embodiments also include structuring the retaining ring such that the distance from the outer surface to the geometric inner surface varies. Embodiments further include structuring the retaining ring such that the distance between the outer surface to the perimeter of the substrate retained by the inner surface of the retaining ring varies.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.