Patent ID: 11948776
Assignee: HITACHI HIGH-TECH CORPORATION
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A plasma processing apparatus comprising:
a process chamber in which a specimen is plasma treated;
a radio frequency power source for supplying microwave frequency power for plasma production;
a rectangular waveguide for transmitting microwaves;
a circular waveguide connected to the rectangular waveguide and transmitting the microwaves to the process chamber; and
a specimen support on which a specimen is placed,
wherein the rectangular waveguide includes: an upper rectangular waveguide and a lower rectangular waveguide formed by vertically dividing the rectangular waveguide; and a cutoff section which cuts off the microwave frequency power supplied from the radio frequency power source, and which is provided with a dielectric body,
the circular waveguide includes: an inner waveguide connected to the upper rectangular waveguide and formed inside; and an outer waveguide connected to the lower rectangular waveguide and formed on an outer side of the inner waveguide, and
a width of the cutoff section is narrower than those of the rectangular waveguides except the cutoff section.