Patent · US Expired

Polishing pad with uniform abrasion

US5020283A · kind A · utility

214Cited by
4References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 3, 1990
Grant dateJun 4, 1991
Priority date
Expiry dateAug 3, 2010

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S451/921
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A polishing pad for semiconductor wafers, having a face shaped by a series of voids. The voids are substantially the same size, but the frequency of the voids increases with increasing radial distance to provide a constant, or nearly constant, surface contact rate to a workpiece such as a semiconductor wafer, in order to effect improved planarity of the workpiece.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.