Skip to Content
Find More Like This
Return to Search

Large area atmospheric-pressure plasma jet

United States Patent

July 17, 2001
View the Complete Patent at the US Patent & Trademark Office
Los Alamos National Laboratory - Visit the Technology Transfer Division Website
Large area atmospheric-pressure plasma jet. A plasma discharge that can be operated at atmospheric pressure and near room temperature using 13.56 MHz rf power is described. Unlike plasma torches, the discharge produces a gas-phase effluent no hotter than C. at an applied power of about 300 W, and shows distinct non-thermal characteristics. In the simplest design, two planar, parallel electrodes are employed to generate a plasma in the volume therebetween. A "jet" of long-lived metastable and reactive species that are capable of rapidly cleaning or etching metals and other materials is generated which extends up to 8 in. beyond the open end of the electrodes. Films and coatings may also be removed by these species. Arcing is prevented in the apparatus by using gas mixtures containing He, which limits ionization, by using high flow velocities, and by properly spacing the rf-powered electrode. Because of the atmospheric pressure operation, there is a negligible density of ions surviving for a sufficiently long distance beyond the active plasma discharge to bombard a workpiece, unlike the situation for low-pressure plasma sources and conventional plasma processing methods.
Selwyn; Gary S. (Los Alamos, NM), Henins; Ivars (Los Alamos, NM), Babayan; Steve E. (Huntington Beach, CA), Hicks; Robert F. (Los Angeles, CA)
The Regents of the University of California (Los Alamos, NM)
09/ 295,942
April 21, 1999
FIELD OF THE INVENTION The present invention relates generally to the generation of plasma discharges and, more particularly, to an apparatus for generating large-area atmospheric-pressure plasmas suitable for materials processing, solvent-free surface cleaning and decontamination. This invention was made with government support under Contract No. W-7405-ENG-36 awarded by the U.S. Department of Energy to The Regents of the University of California. The government has certain rights in the invention.