US Patent 7981262 Process kit for substrate processing chamber

A process kit comprises a shield and ring assembly positioned about a substrate support in a processing chamber to reduce deposition of process deposits on internal chamber components and an overhang edge of the substrate. The shield comprises a cylindrical band having a top wall that surrounds a sputtering target and a bottom wall that surrounds the substrate support, a support ledge, a sloped step, and a U-shaped channel with gas conductance holes. The ring assembly comprises a deposition ring and cover ring, the cover ring having a bulb-shaped protuberance about the periphery of the ring.