Preparation of high performance silica slurry using a centrifuge
US6802983B2 · kind B2 · utility
25Cited by
9References
16Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 17, 2001 |
| Grant date | Oct 12, 2004 |
| Priority date | — |
| Expiry date | Sep 17, 2021 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB24B57/02
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method and system for separating impurities, such as large abrasive particles and foreign matter from an abrasive polishing slurry prior to a Chemical Mechanical Polishing (CMP) procedure performed on a surface of a semiconductor wafer. Impurities greater than about 25 microns are removed by an initial filtration process. The filtrate is then introduced to a solid bowl, sedimentation-type centrifuge to remove particles greater than 0.5 microns thereby providing a polishing slurry for final utilization in a CMP procedure that reduces damage to the surface of the polished semiconductor wafer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.