Patent ID: 7562638

Claim:
A plasma system comprising: a microwave waveguide assembly; an upstream plurality of hollow center electrically conductive, disks; a downstream plurality of hollow center electrically conductive disks; and a plasma tube assembly intersecting said microwave waveguide assembly, said plasma tube assembly having a plasma-sustaining region defined between said upstream plurality of hollow center electrically conductive disks and said downstream plurality of hollow center electrically conductive disks, wherein a first hollow center electrically conductive disk among at least one of said upstream plurality of hollow center electrically conductive disk and said downstream plurality of hollow center electrically conductive disks includes a first downstream corrugated outer surface and a first upstream corrugated outer surface disposed opposite to said first downstream corrugated outer surface, said first hollow center electrically conductive disk further including a first plurality of corrugated peaks disposed on said first downstream corrugated outer surface, said first hollow center electrically conductive disk further including a second plurality of corrugated peaks disposed on said first upstream corrugated outer surface, and a second hollow center electrically conductive disk among at least one of said upstream plurality of hollow center electrically conductive disk and said downstream plurality of hollow center electrically conductive disks includes a second upstream corrugated outer surface and a second downstream corrugated outer surface disposed opposite to said second upstream outer surface, said second hollow center electrically conductive disk further including a third plurality of corrugated peaks disposed on said second downstream corrugated outer surface, said second hollow center electrically conductive disk further including a fourth plurality of corrugated peaks disposed on said second upstream corrugated outer surface, said second upstream corrugated outer surface facing said first downstream corrugated outer surface.