Chemical-mechanical polishing apparatus and method

摘要

A method and apparatus for limiting or eliminating the edge effect in a chemical mechanical polishing apparatus comprising a substrate holder and a retaining ring spaced from and around the holder, a rotatable platen and a polishing pad on the platen, by essentially flattening the pad in the area in which it normally tends to deform. The invention is carried out by applying a fluid under pressure, preferably the polishing slurry, to the pad in the region of the gap between the retaining ring and the holder to substantially flatten the pad in the area around the edge of the substrate.