Patent ID: 8703249

Claim:
A method of supporting a lower electrode on a chamber wall during plasma processing a substrate in a plasma processing chamber, comprising: positioning a clamping ring of electrically insulating material adjacent to the chamber wall of the plasma processing chamber, said clamping ring having a plurality of holes for accommodating a plurality of fasteners, said clamping ring including a plurality of flanges disposed around an outer periphery of said clamping ring, each flange of said plurality of flanges protruding radially outward from said outer periphery of said clamping ring, two adjacent flanges of said plurality of flanges being disposed such that a hole of said plurality of holes that is disposed in between said two adjacent flanges is equidistant from said two adjacent flanges; mating said plurality of flanges with the chamber wall such that gaps between adjacent ones of said plurality of flanges separate surfaces of the clamping ring between the adjacent flanges from the chamber wall; and clamping the lower electrode to the chamber wall by tightening the fasteners.