Plasma processing apparatus and plasma processing method

A plasma processing apparatus, comprising:

• a processing chamber that is disposed inside a vacuum container;
• a sample stage that is disposed inside the processing chamber and on an upper surface of which a wafer to be processed is placed;
• a ring-shaped electrode made of a conductor, which is disposed on an outer peripheral side of the upper surface of the sample stage so as to surround the sample stage and to which radio frequency power is supplied;
• a dielectric cover that is placed above the ring-shaped electrode and covers the ring-shaped electrode;
• a base material that has a disc or cylindrical shape and forms the sample stage, the base material being configured to receive a first radio frequency power from a first radio frequency power source during processing of the wafer;
• a rod that is suspended and disposed in a through hole disposed on an outer peripheral side portion of the base material, and has a connector portion on an upper end portion of the rod connected to the ring-shaped electrode and positioned at the ring-shaped electrode and at a lower end portion exposed in a space below a bottom surface of the base material;
• a beam-shaped member that is disposed below the sample stage below the through hole with a gap therebetween and extends in a horizontal direction, one end of the beam-shaped member is connected to the lower end portion of the rod and a position of another end at least in an upper and lower direction is fixed with respect to the sample stage, and the another end is configured to urge the rod upward with respect to the ring-shaped electrode;
• and
• a second radio frequency power source that is connected to the rod via a power supply path and which supplies second radio frequency power to the ring-shaped electrode.