Wafer and method of producing the same
US7951716B2 · kind B2 · utility
0Cited by
4References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 16, 2007 |
| Grant date | May 31, 2011 |
| Priority date | — |
| Expiry date | Feb 11, 2029 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB24D13/147
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A wafer is produced at a step of polishing a predetermined face of a wafer to flatten the predetermined face while supplying a polishing liquid onto a bonded abrasive cloth, wherein the bonded abrasive cloth comprises a urethane bonding material consisting of a soft segment having a polyfunctional isocyanate and a hard segment having a polyfunctional polyol and having an expansion ratio of 1.1-4 times and silica having an average particle size of 0.2-10 μm and a hydroxy group, and has a given ratio of the hard segment occupied in the urethane bonding material, a given volume ratio of silica and a given Shore D hardness.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.