Patent ID: 7670454

Claim:
A plasma processing apparatus, comprising: a processing vessel defined by an outer wall and having a stage for holding a substrate to be processed: an evacuation system coupled to said processing vessel; a microwave transparent window provided on said processing vessel as a part of said outer wall, and opposite said substrate held on said stage; a plasma gas supplying part for supplying plasma gas to said processing vessel; a microwave antenna provided on said processing vessel in correspondence to said microwave; and a microwave power source electrically coupled to said microwave antenna, wherein said microwave antenna comprises: a coaxial waveguide connected to said microwave power source, said coaxial waveguide having an inner conductor core and an outer conductor tube surrounding said inner conductor core; and an antenna body provided to a point of said coaxial waveguide; said antenna body comprising: a first conductor surface forming a microwave radiation surface coupled with said microwave transparent window provided thereunder; a dielectric plate provided upon said first conductor surface; and a second conductor surface provided upon said dielectric plate and being connected to said first conductor surface at a peripheral part of said dielectric plate, wherein said inner conductor core is connected to said first conductor surface by a first joint unit and said outer conductor tube is connected to said second conductor surface by a second joint unit; wherein said first joint unit forms a first taper unit in which an outer diameter of said inner conductor core increases toward said first conductor surface and said second joint unit forms a second taper unit in which an inner diameter of said outer conductor tube increases toward said first conductor surface; wherein said first taper unit is defined by a first curved surface and said second taper unit is defined by a second curved surface; a dielectric member is provided in a space between said inner conductor core, and said outer conductor tube, said dielectric member being defined by a first edge face and a second edge face opposing said first edge face, said dielectric member being immediately proximate said dielectric plate, a permittivity of said dielectric member being lower than a permittivity of said dielectric plate and higher than a permittivity of air; wherein the microwave plasma processing apparatus further comprising another dielectric member in a space between said inner conductor core and said outer conductor tube, adjacent to said second edge face of said dielectric member, a permittivity of said other dielectric member being lower than a permittivity of said dielectric member and higher than a permittivity of air; and wherein said dielectric member is made of silicon oxide, and said other dielectric member is made of Teflon.