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Title: Charge-state-resolved ion energy distribution functions of cathodic vacuum arcs: A study involving the plasma potential and biased plasmas

Abstract

Charge-state-resolved ion energy distribution functions were measured for pulsed cathodic arcs taking the sheath into account that formed between the plasma and the entrance of a combined energy and mass spectrometer. An electron emitting probe was employed to independently determine the plasma potential. All results were obtained by averaging over several individual measurements because the instantaneous energy distributions and the plasma potential show large amplitude fluctuations due to the explosive nature of the arc plasma generation. It was found that the ion energy distribution functions in the plasma were independent of the ion charge state. This is in contrast to findings with continuously operating, direct-current arcs that employ a magnetic field at the cathode to steer the cathode spot motion. The different findings indicate the important role of the magnetic steering field for the plasma properties of direct-current arcs. The results are further supported by experiments with 'biased plasmas' obtained by shifting the potential of the anode. Finally, it was shown that the ion energy distributions were broader and shifted to higher energy at the beginning of each arc pulse. The characteristic time for relaxation to steady state distributions is about 100 {mu}s.

Authors:
;  [1];  [2]
  1. Lawrence Berkeley National Laboratory, University of California, 1 Cyclotron Road, Berkeley, California 94720 (United States)
  2. (Russian Federation)
Publication Date:
OSTI Identifier:
20982699
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 4; Other Information: DOI: 10.1063/1.2561226; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANODES; CATHODES; CHARGE STATES; DIRECT CURRENT; ELECTRONS; ENERGY SPECTRA; EXPLOSIVES; IONS; MAGNETIC FIELDS; MASS SPECTROMETERS; PLASMA; PLASMA POTENTIAL; PLASMA SHEATH; RELAXATION; STEADY-STATE CONDITIONS

Citation Formats

Anders, Andre, Oks, Efim, and State University of Control Systems and Radioelectronics, Tomsk 634050. Charge-state-resolved ion energy distribution functions of cathodic vacuum arcs: A study involving the plasma potential and biased plasmas. United States: N. p., 2007. Web. doi:10.1063/1.2561226.
Anders, Andre, Oks, Efim, & State University of Control Systems and Radioelectronics, Tomsk 634050. Charge-state-resolved ion energy distribution functions of cathodic vacuum arcs: A study involving the plasma potential and biased plasmas. United States. doi:10.1063/1.2561226.
Anders, Andre, Oks, Efim, and State University of Control Systems and Radioelectronics, Tomsk 634050. Thu . "Charge-state-resolved ion energy distribution functions of cathodic vacuum arcs: A study involving the plasma potential and biased plasmas". United States. doi:10.1063/1.2561226.
@article{osti_20982699,
title = {Charge-state-resolved ion energy distribution functions of cathodic vacuum arcs: A study involving the plasma potential and biased plasmas},
author = {Anders, Andre and Oks, Efim and State University of Control Systems and Radioelectronics, Tomsk 634050},
abstractNote = {Charge-state-resolved ion energy distribution functions were measured for pulsed cathodic arcs taking the sheath into account that formed between the plasma and the entrance of a combined energy and mass spectrometer. An electron emitting probe was employed to independently determine the plasma potential. All results were obtained by averaging over several individual measurements because the instantaneous energy distributions and the plasma potential show large amplitude fluctuations due to the explosive nature of the arc plasma generation. It was found that the ion energy distribution functions in the plasma were independent of the ion charge state. This is in contrast to findings with continuously operating, direct-current arcs that employ a magnetic field at the cathode to steer the cathode spot motion. The different findings indicate the important role of the magnetic steering field for the plasma properties of direct-current arcs. The results are further supported by experiments with 'biased plasmas' obtained by shifting the potential of the anode. Finally, it was shown that the ion energy distributions were broader and shifted to higher energy at the beginning of each arc pulse. The characteristic time for relaxation to steady state distributions is about 100 {mu}s.},
doi = {10.1063/1.2561226},
journal = {Journal of Applied Physics},
number = 4,
volume = 101,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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