The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 23, 1993
Filed:
Oct. 03, 1989
Thomas D Mantei, Cincinnati, OH (US);
University of Cincinnati, Cincinnati, OH (US);
Abstract
An apparatus is provided for the production of plasma. An evacuable chamber is operatively connected to a microwave waveguide, down which microwave energy at approximately 2.45 GHz is transported. The microwave energy enters the evacuable chamber through an opening in the upper wall of the chamber covered by microwave transparent material. Centrally located above the opening in the upper wall of the chamber and outside the waveguide, a permanent magnet is provided. The strong downward magnetic field of the magnet enters the chamber in the same direction as the propagation path of the microwaves. The downward magnetic field component is at a right angle to the electric field associated with the microwaves. A working gas is introduced to the chamber by a plurality of gas inlets operatively connected to the chamber. At some point within the vacuum of the chamber, the electrons rotating about the downward magnetic field component are in phase with the electric field of the microwaves. These electrons acquire sufficient energy at this point to dissociate molecules of the working gas into atoms and to remove electrons from atoms to form ions and free electrons. This plasma of ions, electrons and atoms is then used to perform work on a workpiece provided on a support with the chamber.