Plasma processing apparatus and plasma generation method

A plasma generation method for a plasma processing apparatus, wherein the plasma processing apparatus includes:

• a chamber having a plasma generation space, an emitter formed in an annular shape and disposed above the chamber, and a resonator configured to supply an electromagnetic wave to the emitter,
• wherein the resonator includes a waveguide through which the electromagnetic wave which is generated based on radio-frequency power supplied by a radio-frequency power supply propagates, and a plurality of slots configured to electromagnetically couple the waveguide and the emitter,
• wherein the plurality of slots are formed of a plurality of partial grooves extending in a circumferential direction of the emitter above the emitter,
• wherein a plurality of impedance varying mechanisms for changing an impedance of each of the plurality of slots are disposed so as to correspond to each of the plurality of slots,
• wherein a plurality of coaxial tubes are each disposed between each of the impedance varying mechanisms and the corresponding slots, and
• wherein each of the impedance varying mechanisms is attached to an end of the coaxial tube opposite the corresponding slot, and
• the plasma generation method comprises:
• generating the electromagnetic wave based on the radio-frequency power supplied by the radio-frequency power supply;
• and
• emitting the electromagnetic wave from the emitter into the plasma generation space,
• wherein the impedance of the corresponding slot is changed by the impedance varying mechanism.