Patent ID: 7857683

Claim:
A retaining ring for use in a chemical mechanical polishing operation, comprising: an annular backbone portion having one or more circumferential and axially projecting backbone portion ribs with one or more channels defined by the one or more ribs, the ribs having an axial length substantially greater than a corresponding width and the backbone portion comprising a rigid polymer material; and a wear-resistant polymer base portion having a flat bottom surface, one or more circumferential and axially projecting base portion ribs with one or more channels defined by the one or more ribs, the ribs having an axial length substantially greater than a corresponding width and a plurality of grooves in the bottom surface extending between an inner edge and an outer edge of the retaining ring, the grooves adapted to facilitate transfer of slurry during the polishing operation, wherein the backbone portion and the base portion are bonded together by an overmolding process such that the backbone portion ribs mate to the base portion channels and the base portion ribs mate to the backbone portion channels such that they are directly interlacing and completely conforming with each other, and wherein the backbone portion ribs and the base portion ribs extend a substantial portion of an axial thickness of the bonded backbone portion and base portion.