Patent ID: 9123650
Filing Date: 2015-09-01
Classification: H01J,H01L

Abstract:
1. A plasma confinement ring assembly for a plasma processing chamber, comprising: a mounting ring comprising an inner ring of RF transparent material adapted to be supported on an outer ring, the inner ring including a vertically extending plasma-exposed inner surface, a vertically extending outer surface opposite to the inner surface, and a coating of an electrically-conductive, low-emissivity material on the outer surface wherein the coating is not on the inner surface; and at least two plasma confinement rings arranged in a stack and suspended from the mounting ring; wherein the outer ring comprises a plurality of circumferentially-spaced depressions; a support element removably received in each of the respective plurality of circumferentially-spaced depressions; and the inner ring is adapted to be supported on the support elements; wherein the support elements are round balls of polytetrafluoroethylene or polyetheretherketone which are configured to reduce contact area between the support elements and the inner ring.