DOE Patents title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Atmospheric-pressure plasma jet

Abstract

Atmospheric-pressure plasma jet. A .gamma.-mode, resonant-cavity 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 250.degree. C. at an applied power of about 300 W, and shows distinct non-thermal characteristics. In the simplest design, two concentric cylindrical electrodes are employed to generate a plasma in the annular region 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 shaping the rf-powered electrode. Because of the atmospheric pressure operation, no ions survive for a sufficiently long distance beyond the active plasma discharge to bombard a workpiece, unlike low-pressure plasma sources and conventional plasma processing methods.

Inventors:
 [1]
  1. Los Alamos, NM
Issue Date:
Research Org.:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
OSTI Identifier:
872560
Patent Number(s):
5961772
Assignee:
Regents of University of California (Los Alamos, NM)
Patent Classifications (CPCs):
H - ELECTRICITY H01 - BASIC ELECTRIC ELEMENTS H01J - ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
H - ELECTRICITY H05 - ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR H05H - PLASMA TECHNIQUE
DOE Contract Number:  
W-7405-ENG-36
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
atmospheric-pressure; plasma; jet; gamma; -mode; resonant-cavity; discharge; operated; atmospheric; pressure; near; temperature; 13; 56; mhz; rf; power; described; unlike; torches; produces; gas-phase; effluent; hotter; 250; degree; applied; 300; distinct; non-thermal; characteristics; simplest; design; concentric; cylindrical; electrodes; employed; generate; annular; region; therebetween; long-lived; metastable; reactive; species; capable; rapidly; cleaning; etching; metals; materials; generated; extends; films; coatings; removed; arcing; prevented; apparatus; gas; mixtures; containing; limits; ionization; flow; velocities; properly; shaping; rf-powered; electrode; operation; survive; sufficiently; distance; active; bombard; workpiece; low-pressure; sources; conventional; processing; methods; concentric cylindrical; flow velocities; atmospheric-pressure plasma; processing methods; processing method; pressure plasma; plasma sources; plasma discharge; gas mixtures; plasma source; atmospheric pressure; gas mixture; plasma process; rf power; plasma processing; plasma torch; annular region; reactive species; mixtures containing; plasma jet; thermal characteristics; active species; mhz rf; conventional plasma; cylindrical electrodes; cylindrical electrode; unlike plasma; plasma torches; active plasma; /156/118/315/

Citation Formats

Selwyn, Gary S. Atmospheric-pressure plasma jet. United States: N. p., 1999. Web.
Selwyn, Gary S. Atmospheric-pressure plasma jet. United States.
Selwyn, Gary S. Fri . "Atmospheric-pressure plasma jet". United States. https://www.osti.gov/servlets/purl/872560.
@article{osti_872560,
title = {Atmospheric-pressure plasma jet},
author = {Selwyn, Gary S},
abstractNote = {Atmospheric-pressure plasma jet. A .gamma.-mode, resonant-cavity 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 250.degree. C. at an applied power of about 300 W, and shows distinct non-thermal characteristics. In the simplest design, two concentric cylindrical electrodes are employed to generate a plasma in the annular region 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 shaping the rf-powered electrode. Because of the atmospheric pressure operation, no ions survive for a sufficiently long distance beyond the active plasma discharge to bombard a workpiece, unlike low-pressure plasma sources and conventional plasma processing methods.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 1999},
month = {Fri Jan 01 00:00:00 EST 1999}
}

Works referenced in this record:

The Electric Characteristics of the Ozonator Discharge
journal, January 1943