Apparatus for polishing wafers
US5588902A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 1995 |
| Grant date | Dec 31, 1996 |
| Priority date | — |
| Expiry date | Feb 13, 2015 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB24B37/30
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
The present invention provides an apparatus for polishing wafers, wherein high work efficiency in handling a polishing plate is achieved with high flatness finish of the polished wafers. The apparatus has a polishing plate composed of two plates, which are superimposed in tight adhesion with each other. The thickness of the polishing plate is adjusted to such a value that the polished wafers may be finished with high flatness across the polished surface. An upper plate is mounted to a top ring by means of a a plurality of rigid supporting member consisting of a hook-shaped plate holding portion and a top ring fixing portion such that a predetermined clearance is left between the upper surface of the upper plate and a flexible thin plate arranged on the lower portion of the top ring. The upper and lower plates are polished to be flat and smooth across one side surface to be superimposed of each thereof and then the upper plate and lower plate are superimposed with each other in tight adhesion by surface tension of a liquid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.