Workpiece carrier retaining element

摘要

A wafer carrier retaining ring includes a first annular surface that contacts a polishing surface during a polishing process and an inner diameter surface adjoining the first annular surface thereby forming a first annular corner. The first annular corner has a radius in the range of from no less than about 0.010 inches to less than a radius that would result in damage to a wafer being polished. In another embodiment of the invention, a wafer carrier retaining ring includes an inner diameter surface and a second annular surface adjoining said inner diameter surface thereby forming a second annular corner. The second annular corner has a radius of no less than 0.030 inches. In a further embodiment of the invention, a wafer carrier retaining ring is formed of a ceramic material and has a first annular surface having a surface finish of no greater than 2 microinches rms.