COAXIAL MICROWAVE APPLICATOR FOR PLASMA PRODUCTION

摘要

The disclosure includes a coaxial microwave applicator for plasma production, including a coaxial tube formed by a central core and an outer conductor separated from the central core by an annular space allowing propagation of microwaves. The applicator includes: a cylindrical permanent magnet disposed at the end of the central core; and at least one annular permanent magnet disposed at the end of the outer conductor, all of the magnets disposed at the end of the coaxial tube having the same direction of magnetisation. The magnetisation of the magnets forms a magnetic field suitable for generating, in a zone away from the end of the applicator, an electronic cyclotronic resonance coupling with the electric microwave field of the applicator. The external radius and the magnetisation of the annular magnet are selected such that the magnetic field lines generated by the magnets pass through the coupling zone in a direction substantially parallel to the axis of the applicator.

主权项

1. A coaxial microwave applicator for plasma production, including an electrically conductive coaxial tube comprising a central core and of an outer conductor surrounding the central core and separated therefrom by an annular volume for propagation of microwaves, the applicator comprising:
a cylindrical permanent magnet, magnetization whereof being parallel to an axis of the applicator, positioned at an end of the central core; and at least one annular permanent magnet, a magnetization direction whereof being parallel to the axis of the applicator, and concurrent with the magnetization of the central cylindrical magnet, positioned at an end of the outer conductor; wherein all the magnets positioned at an end of the coaxial tube have the same magnetization direction; wherein the magnetization of the magnets is selected so as to form a magnetic field suited to providing, in a region remote from an end of the applicator, electron cyclotron resonance coupling with a microwave electric field generated by the applicator; and wherein an outer radius and the magnetization of the annular magnet are further being selected so that magnetic field lines generated by the magnets pass through the electron cyclotron resonance coupling region in a direction substantially parallel to the axis of the applicator.