Polishing apparatus

摘要

A polishing apparatus comprising:
a polishing pad having a polishing surface;
a top ring body configured to press a substrate against said polishing surface;
a retainer ring (502) configured to press said polishing surface, said retainer ring being provided at a peripheral portion of said top ring body;
a pusher (800) operable to receive the substrate from and deliver the substrate to said top ring body; and ·
a retainer ring wear detector (840) for detecting wear of said retainer ring, said retainer ring wear detector being provided in said pusher.