A method of operating a chemical mechanical planarization (CMP) tool includes attaching a polishing pad to a first surface of a platen of the CMP tool using a glue; removing the polishing pad from the platen, wherein after removing the polishing pad, residue portions of the glue remain on the first surface of the platen; identifying locations of the residue portions of the glue on the first surface of the platen using a fluorescent material; and removing the residue portions of the glue from the first surface of the platen.