PLASMA PROCESSING METHOD AND PLASMA PROCESSING APPARATUS

摘要

PURPOSE: A plasma processing method and a plasma processing apparatus are provided to improve the selectivity of an etching rate of a polysilicon layer to a silicon oxide layer by reducing a duty ratio below 50%. CONSTITUTION: Plasma is easily generated by a plasma discharge. Power of an on cycle of high frequency power easily generates plasma by a continuous discharge. The average power of one cycle of the high frequency power becomes power in a region in which the plasma is not generated by the continuous discharge with the duty ratio of the plasma discharge. [Reference numerals] (AA) Polysilicon/silicon oxide film selection ratio; (BB) Holding Vpp 350V; (CC) Duty 20%; (DD) Duty 50%; (EE) Duty 65%; (FF) Average microwave power(W)