Method to remove residue in wolfram CMP
US6153526A · kind A · utility
12Cited by
10References
37Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 27, 1999 |
| Grant date | Nov 28, 2000 |
| Priority date | — |
| Expiry date | May 27, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/3212
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A new method for removing particle residue from the surface of semiconductor wafers that contain wolfram plugs. A series of polishing and buffing steps is performed; the first of this is a wolfram CMP using a hard polishing pad. An oxide buffing operation is further performed on the wafer surface; a soft pad is used for this buffing operation. The buffing operation is followed by a wolfram CMP that is applied for a short period of time using a soft polishing pad thereby removing the protruding top of the wolfram plug and the oxide particles from the vicinity of the wolfram plugs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.