Patent ID: 7325511

Claim:
A microwave plasma processing apparatus for applying plasma processing to a substrate, said apparatus comprising: a processing vessel accommodating therein a stage for supporting said substrate; a microwave generator; a waveguide connected to said microwave generator, said waveguide adapted to guide a microwave generated by said microwave generator; a microwave emitting member comprising a retardation plate disposed over a slot antenna member, adapted to emit said microwave into a space in said processing vessel after wavelength compression by the retardation plate; and a dielectric plate sealably mounted on an upper opening of said processing vessel, wherein said microwave emitting member is disposed over said dielectric plate and said slot antenna member is disposed over said dielectric plate, and wherein said waveguide has a portion having an outer surface that is in physical contact with said retardation plate and a respective inner surface opposed to and parallel to said outer surface that is exposed to microwaves, said portion of said waveguide being a rectangular waveguide and having a microwave outlet opening at a location corresponding to a center of said microwave emitting member.