Laboratory for Manufacturing and Sustainability

In this study, surface topographies of different pad samples from varying in-situ conditioning processes and differing pad life stages have been measured by white light interferometer. Copper removal rate and within wafer non-uniformity was monitored during pad degradation test. Pad surface height distribution, measured from white light interferometer, was more dependent on the plastic deformation and wear at the retaining ring and wafer contact region than on in-situ conditioning. Also, the overall removal rate in copper CMP was more dependent on the slurry flow than on pad surface height distribution.