PLASMA PROCESSING METHOD AND PLASMA PROCESSING APPARATUS

A plasma processing method including disposing a wafer to be processed on a sample stage disposed in a processing chamber within a vacuum vessel, supplying an electric field using first high frequency power for plasma forming into the processing chamber and forming plasma, and supplying second high frequency power for bias potential forming to electrodes disposed within the sample stage and processing a film on a top surface of the wafer. At least the first or second high frequency power repeats a change of becoming a plurality of predetermined amplitudes for predetermined periods with a predetermined repetition period. In the processing of the film, supply of the high frequency power is changed by finally increasing a predetermined magnitude of amplitude among the repetition period, ratio of the period, and amplitude of the at least the first or second high frequency power, or first decreasing a predetermined magnitude of the amplitude.