Apparatus for chemical mechanical polishing

Abstract

The present invention provides a chemical mechanical polishing apparatus for polishing a wafer. The chemical mechanical polishing apparatus comprises a platen, a polishing pad, a transparent element (transparent window), a slurry providing system, and a rotating carrier. The platen comprises a light source for projecting a light and a light detector for detecting the light reflected by the wafer. The polishing pad has a first opening on the platen. The transparent element is detachably located on the first opening to admit light. The slurry providing system provides slurry to the surface of the polishing pad. The rotating carrier holds the wafer and contacts the surface of the wafer with the slurry and the polishing pad to carry out the chemical mechanical polishing process.

Dependencies are inferred from the claim text.