Polishing pad

Abstract

A polishing pad includes a pad body; and a transparent window integrally formed in the pad body. The window is formed of a material which is more susceptible to abrasion than a material of the pad body. The pad body has a plurality of grooves formed in a surface thereof, and the window has no grooves in a surface thereof. A surface of the window is recessed with respect to a surface of the pad. The polishing pad prevents a slurry from settling on the window so as to improve the detection precision of the polishing rate. Furthermore, the polishing pad prevents the window from gradually projecting with respect to the pad body by dressing during polishing so as to substantially eliminate adverse effect on the polishing characteristic.

Dependencies are inferred from the claim text.