Polishing head of a chemical and mechanical polishing apparatus

摘要

A polishing head of a chemical and mechanical polishing apparatus includes a retainer ring which adheres more uniformly to a polishing pad. The retainer ring surrounds and protects a wafer chucked to the polishing head. The bottom surface of the retainer ring is inclined by a predetermined angle from the outer periphery thereof towards the inner periphery thereof. A resilient fixing plate disposed against the upper surface of the inner peripheral portion of the retainer ring provides a seal between the retainer ring and the carrier. Therefore, when the retainer ring is pressed against a polishing pad and the inner peripheral portion of the retainer ring is pushed downwardly due to the resiliency of the fixing plate, the retainer ring flexes such that uniform pressure is produced between the bottom surface of the retainer ring and the polishing pad. Hence, the wafer will be polished uniformly.