Patent ID: 7909960

Claim:
A plasma etch processing chamber configured to clean a bevel edge of a substrate, the plasma etch processing chamber comprising: a bottom edge electrode surrounding a substrate support in the plasma processing chamber, having at least a portion of a top surface at the same lever as a top surface of the substrate support, wherein the substrate support is configured to receive the substrate; a bottom dielectric ring disposed between the bottom edge electrode and the substrate support, the bottom dielectric ring surrounding the substrate support, the bottom dielectric ring electrically separating the substrate support and the bottom edge electrode; a gas distribution plate opposing the substrate support, the gas distribution plate including at least a gas feed for supplying a gas; a top dielectric ring surrounding the gas distribution plate; a top edge electrode surrounding the gas distribution plate opposing the substrate support, wherein the top dielectric ring is disposed between the top edge electrode and the gas distribution plate, and the top edge electrode and the gas distribution plate are electrically isolated from each other by the top dielectric ring; and a bottom insulating ring surrounding and coupled to the bottom edge electrode, wherein the bottom edge electrode is disposed between the bottom insulating ring and the bottom dielectric ring, and wherein an inner portion of the bottom insulating ring is taller than an outer portion of the bottom insulating ring, the inner portion of the bottom insulating ring being disposed closer to the bottom edge electrode than the outer portion of the bottom insulating ring.