End-point detection apparatus

摘要

An apparatus is provided for polishing a substrate. The apparatus includes a polishing pad configured to traverse from at least a first point to a second point. A first sensor is located near the first point and oriented so as to sense an incoming temperature of the polishing pad. A second sensor is located near the second point and oriented so as to sense an outgoing temperature of the polishing pad. A difference between the incoming temperature and the outgoing temperature is then used to determine endpoint of a polishing operation.