A COMPOSITE SHOWERHEAD ELECTRODE ASSEMBLY FOR A PLASMA PROCESSING APPARATUS

摘要

The showerhead electrode for the plasma processing apparatus includes an interface gel between the electrode plate and the opposing faces of the backing plate. The interface gel maintains thermal conductivity during transverse displacement caused during temperature cycling due to mismatch in thermal expansion coefficient. The interface gel includes, for example, a silicone-based composite filled with aluminum oxide microspheres. The interface gel can conform to irregularly shaped features and maximize the surface contact area between mating surfaces. The interface gel may be pre-applied to the consumable top electrode.