Patent ID: 7169255

Claim:
A plasma processing apparatus for providing a plasma processing to an object to be processed disposed within a vacuum processing chamber, the plasma processing apparatus comprising: a vacuum processing chamber; a process gas feeding device for feeding process gas into the vacuum processing chamber; a wafer electrode placed within the vacuum processing chamber for mounting the object to be processed; a wafer bias power generator for applying self-bias voltage to the wafer electrode; a plasma generating means for generating plasma within the vacuum processing chamber; and a clip circuit provided for the wafer bias power generator for clipping at least either a positive side voltage or a negative side voltage of a high frequency voltage applied to the wafer electrode for mounting the object to be processed so that the absolute value of voltage applied to the wafer electrode increases in an inclined manner with time, and so that a voltage waveform of a high frequency voltage generated to the object to be processed which is mounted on the wafer electrode is controlled to be flattened at an arbitrary voltage either on a positive side voltage or a negative side voltage wherein the clip circuit comprises a diode and a DC voltage unit that are mutually connected in series, and adapted to control the voltage of the DC power supply unit in the clip circuit in order to adjust the inclination of the clip voltage so that the absolute value of voltage increases with time.