Patent ID: 7166166

Claim:
A baffle plate for a plasma processing system, comprising: a canted ring comprising an upper surface and a lower surface, said canted ring further including a first section and a second section, wherein said second section extends at an angle with respect to said first section such that said second section is inclined with respect to said first section, and wherein said canted ring includes an outer radial edge associated with said first section and an inner radial edge associated with said second section, said inner radial edge including an inner edge surface; wherein said second section comprises at least one passageway extending through said second section from said upper surface to said lower surface and configured to permit the flow of a gas there through, each of said at least one passageway comprising an internal passageway surface, and wherein said first section comprises: a first mating surface on the upper surface of the canted ring proximate said outer radial edge and configured to mate with the plasma processing system, and a second mating surface on the lower surface of the canted ring proximate said outer radial edge and configured to mate with the plasma processing system, and wherein: an upper surface in said first section of said canted ring includes a recess outside an area of the first mating surface which extends partially but not completely through a thickness of said first section, a lower surface in said first section of said canted ring includes another recess outside an area of the second mating surface which extends partially but not completely through a thickness of said first section, and a protrusion positioned adjacent to and radially inward of said another recess and extending from said lower surface in the first section; and a protective barrier provided on a plurality of exposed surfaces of said baffle plate, wherein said exposed surfaces comprise said upper surface including a portion of said recess but excluding said first mating surface, said lower surface including said protrusion and a portion of said another recess but excluding said second mating surface, said inner edge surface of said inner radial edge, and said internal passageway surface of each of said at least one passageway.