There is included a process container; a gas supply system; and a coil provided with a section between a first grounding point and a second grounding point of the coil so as to be spirally wound a plurality of times along an outer periphery of the process container, wherein the coil is configured so that a coil separation distance, which is a distance from an inner periphery of the coil to an inner periphery of the process container, in a partial section of a first winding section, which is a section where the coil winds once along the outer periphery of the process container in a direction from the first grounding point toward the second grounding point, is longer than a coil separation distance in another partial section of the first winding section continuous with the partial section of the first winding section.