Patent · US Expired

Method and apparatus for detecting an end-point in chemical mechanical polishing of metal layers

US6652355B2 · kind B2 · utility

38Cited by
17References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 4, 2001
Grant dateNov 25, 2003
Priority date
Expiry dateDec 6, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/3212
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

An apparatus, as well as a method, determines an endpoint of chemical mechanical polishing a metal layer on a substrate. The method of the apparatus includes bringing a surface of a substrate into contact with a polishing pad that has a window; causing relative motion between the substrate and the polishing pad; directing a light beam through the window, the motion of the polishing pad relative to the substrate causing the light beam to move in a path across the substrate; detecting light beam reflections from the substrate and a retaining ring; generating reflection data associated with the light beam reflections; dividing the reflection data into a plurality of radial ranges; and identifying the predetermined pattern from the reflection data in the plurality of radial ranges to establish the endpoint.

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