Patent attributes
In a plasma processing apparatus, a controller controls one or both of a first high frequency power supply and a second high frequency power supply to periodically stop the supply of one or both of the first high frequency power and the second high frequency power. The controller also controls a switching unit to apply a DC voltage to a focus ring from a first time after a predetermined period of time in which a self-bias voltage of a lower electrode is decreased from a start point of each period in which one or both of the first high frequency power and the second high frequency power are supplied and to stop the application of the DC voltage to the focus ring during each period in which the supply of one or both of the first high frequency power and the second high frequency power is stopped.
