MULTILAYER RETAINING RING FOR CHEMICAL MECHANICAL POLISHING

摘要

A carrier head (100) for a chemical mechanical polishing apparatus includes a retaining ring (110) having a flexible lower portion (108) and a rigid upper portion (184). A shim (202) can be inserted between the retaining ring (110) and a base (104) of the carrier head to improve the retaining ring (110) lifetime. A seal (200) may be inserted between the retaining ring (110) and a flexible membrane to seal the chamber (190) between the flexible membrane and the base.