Patent ID: 7305934

Claim:
A plasma processing apparatus comprising: a pedestal on which a substrate is to be placed; a process chamber where said pedestal is to be accommodated; a power feed unit to supply a 2.45-GHz high-frequency electromagnetic field, wherein said power feed unit has: a cylindrical waveguide which conducts the high-frequency electromagnetic field; a waveguide having one surface connected to one end of said cylindrical waveguide and where the one surface of the waveguide includes a circular polarization antenna which is arranged at a first end of said cylindrical waveguide, and introduces into said cylindrical waveguide the high-frequency electromagnetic field as a rotating electromagnetic field which rotates in a plane perpendicular to a traveling direction of the high-frequency electromagnetic field and where the circular polarization antenna includes two slots which have different lengths and intersect each other at centers thereof whose frequency characteristics with respect to 2.45 GHz relatively differ by 55° to 70° and which emit electric fields whose amplitudes are equal; and a radial waveguide which is interposed between said cylindrical waveguide and the process chamber and has two opposing surfaces, wherein a second end of said cylindrical waveguide is open to one of the two opposing surfaces, a slot antenna formed in the other one of the two surfaces, and the radial waveguide supplies the high-frequency electromagnetic field introduced from said cylindrical waveguide into said process chamber through said slot antenna.