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Title: Characterization of a low-pressure argon plasma using optical emission spectroscopy and a global model

Abstract

The excitation mechanisms of the lower lying excited levels in a low-ionized, low-pressure, argon plasma are modeled and studied in order to characterize the plasma through optical emission spectroscopy. It is found that the lower lying excited states of argon play an important role in the excitation and that they must be taken explicitly into account for an accurate determination of the excitation rates. The possible influence of radiative cascades from upper argon excited states, which are not included in the model, has been studied by introducing an effective level in the description and studying its influence on the results. The model has been used to calculate the electron density and electron temperature in an argon magnetron sputtering plasma produced at different electromagnetic powers and gas pressures, as a function of the intensity of the optical emission lines {lambda}{sub 1}=750.38 nm and {lambda}{sub 2}=696.54 nm. The results obtained from the model have been compared with Langmuir probe measurements, showing a good agreement. It is hereby demonstrated that optical emission spectroscopy can be used to monitor the plasma properties during the deposition process when applying a nonlinear model.

Authors:
; ; ;  [1]
  1. Surfaces, Interfaces and Devices, Department of Physics and Astronomy, Utrecht University, P.O. Box 80.000, 3508TA Utrecht (Netherlands)
Publication Date:
OSTI Identifier:
20982721
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 5; Other Information: DOI: 10.1063/1.2559790; (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; 36 MATERIALS SCIENCE; ARGON; DEPOSITION; ELECTRON DENSITY; ELECTRON TEMPERATURE; EMISSION SPECTROSCOPY; EXCITATION; EXCITED STATES; ION TEMPERATURE; LANGMUIR PROBE; MATHEMATICAL MODELS; NONLINEAR PROBLEMS; PLASMA; PLASMA DENSITY; PLASMA SIMULATION; SPUTTERING

Citation Formats

Palmero, A., Hattum, E. D. van, Rudolph, H., and Habraken, F. H. P. M.. Characterization of a low-pressure argon plasma using optical emission spectroscopy and a global model. United States: N. p., 2007. Web. doi:10.1063/1.2559790.
Palmero, A., Hattum, E. D. van, Rudolph, H., & Habraken, F. H. P. M.. Characterization of a low-pressure argon plasma using optical emission spectroscopy and a global model. United States. doi:10.1063/1.2559790.
Palmero, A., Hattum, E. D. van, Rudolph, H., and Habraken, F. H. P. M.. Thu . "Characterization of a low-pressure argon plasma using optical emission spectroscopy and a global model". United States. doi:10.1063/1.2559790.
@article{osti_20982721,
title = {Characterization of a low-pressure argon plasma using optical emission spectroscopy and a global model},
author = {Palmero, A. and Hattum, E. D. van and Rudolph, H. and Habraken, F. H. P. M.},
abstractNote = {The excitation mechanisms of the lower lying excited levels in a low-ionized, low-pressure, argon plasma are modeled and studied in order to characterize the plasma through optical emission spectroscopy. It is found that the lower lying excited states of argon play an important role in the excitation and that they must be taken explicitly into account for an accurate determination of the excitation rates. The possible influence of radiative cascades from upper argon excited states, which are not included in the model, has been studied by introducing an effective level in the description and studying its influence on the results. The model has been used to calculate the electron density and electron temperature in an argon magnetron sputtering plasma produced at different electromagnetic powers and gas pressures, as a function of the intensity of the optical emission lines {lambda}{sub 1}=750.38 nm and {lambda}{sub 2}=696.54 nm. The results obtained from the model have been compared with Langmuir probe measurements, showing a good agreement. It is hereby demonstrated that optical emission spectroscopy can be used to monitor the plasma properties during the deposition process when applying a nonlinear model.},
doi = {10.1063/1.2559790},
journal = {Journal of Applied Physics},
number = 5,
volume = 101,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2007},
month = {Thu Mar 01 00:00:00 EST 2007}
}
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