US Patent 8636872 Upper electrode and plasma processing apparatus

Plasma uniformity can be improved. An upper electrode 105 for use in a parallel plate type plasma processing apparatus includes a base 105a made of a dielectric material; and a conductive layer 110 formed on at least a part of a surface of the base 105a facing a lower electrode 210 provided in the plasma processing apparatus. Further, the conductive layer 110 having a dense and sparse pattern such that the dense and sparse pattern at an outer portion of the surface of the base 105a facing the lower electrode 210 is denser than at an inner portion thereof.