Method and apparatus for in-situ endpoint detection using electrical sensors

The present invention relates generally to the art of monitoring a wafer's surface during a planarization process, and more particularly, relates to an improved apparatus whereby a plurality of electrical probes are used to detect endpoint during a chemical-mechanical planarization process. A method and apparatus for determining the endpoint of a planarization process during chemical mechanical planarization (CMP) and more specifically for determining endpoint of a planarization process for a thin metal film deposited on a wafer's surface and/or a method of altering the plating and deplating of the thin metal film during the planarization process. The apparatus includes one or more probes embedded in a working surface. The probes are in electrical communication with the thin film on the wafer's surface as it is planarized against the working surface. The probes measure the thickness of the thin metal film and/or induce a current in the thin metal film to adjust the plating and deplating that occurs during the planarization process.