skip to main content

Title: One-dimensional Ar-SF{sub 6} hydromodel at low-pressure in e-beam generated plasmas

A one-dimensional steady-state hydrodynamic model of electron beam generated plasmas produced in Ar-SF{sub 6} mixtures at low pressure in a constant magnetic field was developed. Simulations were performed for a range of SF{sub 6} partial pressures at constant 30 mTorr total gas pressure to determine the spatial distribution of species densities and fluxes. With the addition of small amount of SF{sub 6} (∼1%), the confining electrostatic field sharply decreases with respect to the pure argon case. This effect is due to the applied magnetic field inhibiting electron diffusion. The hallmark of electronegative discharge plasmas, positive ion—negative ion core and positive ion—electron edge, was not observed. Instead, a plasma with large electronegativity (∼100) is formed throughout the volume, and only a small fraction (≈30%) of the parent SF{sub 6} molecules were dissociated to F{sub 2}, SF{sub 2}, and SF{sub 4}. Importantly, F radical densities were found to be very low, on the order of the ion density. Model predictions for the electron density, ion density, and plasma electronegativity are in good agreement with experimental data over the entire range of SF{sub 6} concentrations investigated.
Authors:
; ; ;  [1]
  1. Plasma Physics Division, Naval Research Laboratory, 4555 Overlook Ave. SW, Washington DC 20375-5346 (United States)
Publication Date:
OSTI Identifier:
22489794
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 34; Journal Issue: 2; Other Information: (c) 2016 U.S. Government; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 36 MATERIALS SCIENCE; ARGON; CATIONS; DENSITY; ELECTRON BEAMS; ELECTRON DENSITY; HYDRODYNAMIC MODEL; ION DENSITY; PLASMA; SULFUR FLUORIDES