Uniformly cooled plasma etching electrode

摘要

A planar electrode (17) having a plurality of concentric channels (34-34) therein through which coolant fluid passes to cool the electrode during a plasma etching process. The coolant is directed through at least two of the adjacent channels in opposite directions with the inputs (31) and outputs (32) located in close spaced relation to one another to provide a substantially uniform temperature on the surface of the electrode proximate thereto.