Patent ID: 7743730

Claim:
An electrode assembly configured to provide a ground path for a plasma processing chamber of a plasma processing system, said electrode assembly comprising: an electrode configured to be exposed to a plasma; a heater plate disposed above said electrode, wherein said heater plate is configured to heat said electrode; a cooling plate disposed above said heater plate, wherein said cooling plate is configured to cool said electrode; a plasma chamber lid configured to confine said plasma in said plasma chamber, wherein said plasma chamber lid includes a ground; a clamp ring configured to secure said electrode to said plasma chamber lid, wherein said clamp ring and said electrode form a basket with at least said heater plate being placed inside said basket such that said clamp ring surrounds said heater plate, said basket is configured to allow longitudinal and lateral tolerances for thermal expansion of said heater plate from repetitive thermal cycling, said clamp ring being further configured to provide said ground path from said electrode to said chamber lid; and a shield shielding at least a portion of a bottom of said clamp ring, said portion of said bottom of said clamp ring being disposed between said shield and said electrode, said shield including a ledge disposed under said portion of said bottom of said clamp ring, said portion of said clamp ring disposed under an outer annular portion of said electrode.