Polishing pad with controlled abrasion rate
US5297364A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 9, 1991 |
| Grant date | Mar 29, 1994 |
| Priority date | — |
| Expiry date | Oct 9, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S451/921
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A polishing pad is provided, having its face shaped to produce controlled nonuniform removal of material from a workpiece. Non-uniformity is produced as a function of distance from the pad's rotational axis (the working radius). The pad face is configured with both raised, contact regions and voided, non-contact regions such that arcuate abrasive contact varies nonuniformly as a function of distance from the pad's rotational axis. Void density at any distance may be produced by several techniques such as varying void size as a function of working radius or varying the number of voids per unit area as a function of working radius. Either technique produces variation in voided area per total unit area for rings of pad surface concentric with the rotational axis having infintesimally small width.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.