Polishing head, retaining ring for use therewith and method fo polishing a substrate

摘要

A polishing apparatus is provided for removing material from a surface of a substrate. The apparatus includes a polishing head for positioning a surface of a substrate against a polishing surface of the apparatus. The polishing head includes a subcarrier adapted to hold the substrate during a polishing operation, and a retaining ring having an inner edge disposed about the subcarrier and a lower surface in contact with the polishing surface during the polishing operation, the lower surface of the retaining ring having a number of radial recesses formed therein to distribute a chemical between the substrate held on the subcarrier and the polishing surface when there is relative motion between the substrate and the polishing surface, thereby inhibiting non-planar polishing of the surface of the substrate. Preferably, the number of radial recesses comprise at least one groove adapted to transport the chemical from an area near an outer edge of the retaining ring to an area near an inner edge of the retaining ring. More preferably, the groove comprises a chevron shape between the outer and inner edge of the retaining ring.