ELECTRODE PLATE FOR PLASMA-ETCHING

摘要

PURPOSE:To perform uniform etching, to eliminate unsatisfactory etching rates and to increase the life of an electrode plate. CONSTITUTION:An electrode plate for plasma-etching has a disclike electrode plate body 1 made of vitreous carbon of high purity and formed with many through holes 4 each having a miniature diameter. A plurality of spherical recesses 5 are formed on an inner peripheral surface of each hole 4 thereby to facilitate concentration of charge and to increase a charge area on the plate.