Patent ID: 8580092

Claim:
A shield for encircling a sputtering surface of a sputtering target that faces a substrate support in a substrate processing chamber, the shield comprising: a cylindrical outer band having a first diameter sized to encircle the sputtering surface of the sputtering target, the cylindrical outer band having a top end sized to surround the sputtering surface and a bottom end sized to surround the substrate support, a sloped step having a second diameter greater than the first diameter that extends radially outward from the top end of the cylindrical outer band; a mounting flange extending radially outward from the sloped step; a base plate coupled to and extending radially inward from the bottom end of the cylindrical outer band; and a cylindrical inner band coupled with the base plate, the base plate coupled between the bottom end of the cylindrical outer band and a bottom end of the cylindrical inner band, the cylindrical inner band sized to encircle a peripheral edge of the substrate support, wherein the cylindrical inner band has a plurality of holes each for containing a centering mechanism having a cylindrical holder to maintain a controlled gap between the shield and a cover ring evenly around a diameter of the shield, wherein the centering mechanism comprises a ball for providing point contact with the cover ring.