US Patent 12112925 Plasma processing apparatus

A plasma processing apparatus includes: a plasma processing chamber; a radio frequency power source; a sample stage on which a sample is mounted; an electrode which is arranged inside the sample stage and electrostatically chucks the sample; a DC power source which applies a DC voltage to the electrode; and a control device which controls an output voltage of the DC power source so that an electric potential difference between an electric potential of the sample and an electric potential of an inner wall of the plasma processing chamber is reduced to an electric potential difference within a predetermined range during interruption of plasma discharge.