TWO-PART PLASTIC RETAINING RING

摘要

A retaining ring includes a generally annular lower portion and a generally annular upper portion. The lower portion has a bottom surface for contacting a polishing pad during polishing and a top surface. The upper portion has a bottom surface secured to the top surface of the lower portion and a top surface configured to be mechanically affixed to and abut a rigid base of a carrier head. The lower portion is a first plastic, and the upper portion is a different second plastic that is about the same or more rigid than the first plastic.