Patent ID: 7728251

Claim:
A plasma processing apparatus comprising: a processing chamber configured to enclose and process a substrate; an electromagnetic source configured to output electromagnetic waves; a plurality of waveguides configured to propagate the electromagnetic waves; a waveguide antenna including a plurality of slots formed in each of the plurality of waveguides and configured to radiate the electromagnetic waves; a plurality of dielectric windows formed of a dielectric material to transmit the electromagnetic waves, associated with the plurality of slots, and form a surface that is oriented towards an inner space of the processing chamber and are supported air tightly by metallic beams; and a plurality of dielectric plates arranged between the plurality of dielectric windows and the processing chamber, sidewalls of adjacent dielectric plates of the plurality of dielectric plates being in direct contact with each other, the plurality of dielectric plates provided on inner surfaces of the plurality of dielectric windows and metallic beams, which support the plurality of dielectric windows in the processing chamber, such that plasma is continuously and uniformly produced in the processing chamber, and a thickness of each of the dielectric plates in direction of propagation of the electromagnetic waves is set substantially at a half a wavelength or more of the electromagnetic waves inside the dielectric plates, wherein the plasma processing apparatus is configured to generate plasma by the electromagnetic waves that are radiated from the slots into the processing chamber via the plurality of dielectric windows, and the generated plasma is configured to process the substrate inside the processing chamber, and wherein the plurality of dielectric plates are arranged such that a location where the plates are laterally in contact with each other is located under the plurality of dielectric windows, and is centered between the side edges of the plurality of dielectric windows so as not to be under a seam of adjacent dielectric windows, and the plurality of dielectric plates are attached to a lower surface of the metallic beams by fixing members.