Patent attributes
A method and apparatus for the removal of a deposited conductive layer along an edge of a substrate using an electrode configured to electro polish a substrate edge are disclosed. The electro polishing of the substrate edge may occur simultaneously during electrochemical mechanical processing (Ecmp) of a substrate face. In one embodiment, a power source applies a bias between the substrate and at least two electrodes. The electrodes form a first electrode zone proximate the substrate edge at a sufficient potential to electro polish the substrate edge, thereby removing the conductive layer from the substrate edge. A second electrode zone with a lower potential than the first electrode zone is aligned proximate the substrate face during processing to enable Ecmp of the substrate face.