Plasma processing apparatus

A plasma processing apparatus comprising:

• a chamber;
• a coaxial waveguide including an outer conductor of a cylindrical shape and an inner conductor provided inward of the outer conductor to provide a gas flow path in the inner conductor;
• an introducer provided to introduce electromagnetic waves from the coaxial waveguide into the chamber;
• a shower head connected to the gas flow path and configured to provide a plurality of gas holes that are open toward an internal space of the chamber;
• one or more conductor parts made of a metal and provided to extend in a direction crossing the coaxial waveguide so as to be connected to the inner conductor between a first end and a second end of the inner conductor, the one or more conductor parts including a gas pipe connected to the gas flow path;
• and
• one or more filters configured to prevent the electromagnetic waves from propagating around the one or more conductor parts, wherein each of the one or more filters includes a cylindrical cover conductor provided to surround a corresponding conductor part among the one or more conductor parts, and the cover conductor includes a third end connected to the outer conductor and a fourth end that is a short-circuit end connected to the corresponding conductor part,
• wherein the one or more conductor parts includes a plurality of conductor parts,
• wherein the one or more filters includes a plurality of filters, and
• wherein the plurality of conductor parts and the plurality of filters are evenly arranged in a circumferential direction around the coaxial waveguide.