Polishing apparatus and polishing method

摘要

A polishing apparatus is used for polishing and planarizing a substrate such as a semiconductor wafer on which a conductive film such as a copper (Cu) layer or a tungsten (W) layer is formed. The polishing apparatus includes a polishing table having a polishing surface, a motor for rotating the polishing table, a top ring for holding a substrate and pressing the substrate against the polishing surface, a film thickness measuring sensor disposed in the polishing table for scanning a surface of the substrate, and a computing device for processing signals of the film thickness measuring sensor to compute a film thickness of the substrate.