IMPROVED RETAINING RING FOR WAFER CARRIERS

摘要

A long-lasting retaining ring for wafer carriers used in chemical mechanical planarization. A groove is disposed around the retaining ring, with the groove opening facing the mounting plate. A ridge is disposed in the groove. A bladder is disposed in the groove and is pressed between the ridge and the mounting plate. Pressure in the bladder can be maintained or adjusted to deform the bladder and thereby force the retaining ring onto the polishing pad as the retaining ring is worn.