Patent · US Expired

Wafer polishing device with movable window

US6254459A · kind A · utility

86Cited by
63References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 6, 1999
Grant dateJul 3, 2001
Priority date
Expiry dateDec 6, 2019

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB24B49/12
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A wafer polishing device with movable window can be used for in-situ monitoring of a wafer during CMP processing. During most of the CMP operation, the window remains below a polishing surface of a polishing device to protect the window from the deleterious effects of the polishing process. When the window moves into position between the wafer and a measurement sensor, the window is moved closer to the polishing surface. In this position, at least some polishing agent collected in the recess above the window is removed, and an in-situ measurement can be taken with reduced interference from the polishing agent. After the window is positioned away from the wafer and measurement sensor, the window moves farther away from the wafer and polishing surface. With such a movable window, the limitations of current polishing devices are overcome.

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