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Title: Electron energy distributions and electron impact source functions in Ar/N{sub 2} inductively coupled plasmas using pulsed power

Abstract

In plasma materials processing, such as plasma etching, control of the time-averaged electron energy distributions (EEDs) in the plasma allows for control of the time-averaged electron impact source functions of reactive species in the plasma and their fluxes to surfaces. One potential method for refining the control of EEDs is through the use of pulsed power. Inductively coupled plasmas (ICPs) are attractive for using pulsed power in this manner because the EEDs are dominantly controlled by the ICP power as opposed to the bias power applied to the substrate. In this paper, we discuss results from a computational investigation of EEDs and electron impact source functions in low pressure (5–50 mTorr) ICPs sustained in Ar/N{sub 2} for various duty cycles. We find there is an ability to control EEDs, and thus source functions, by pulsing the ICP power, with the greatest variability of the EEDs located within the skin depth of the electromagnetic field. The transit time of hot electrons produced in the skin depth at the onset of pulse power produces a delay in the response of the EEDs as a function of distance from the coils. The choice of ICP pressure has a large impact on the dynamicsmore » of the EEDs, whereas duty cycle has a small influence on time-averaged EEDs and source functions.« less

Authors:
;  [1]
  1. Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Ave., Ann Arbor, Michigan 48109-2122 (United States)
Publication Date:
OSTI Identifier:
22412985
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 4; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ELECTROMAGNETIC FIELDS; ELECTRONS; ENERGY SPECTRA; PLASMA; PRESSURE DEPENDENCE; PULSES; SUBSTRATES; SURFACES

Citation Formats

Logue, Michael D., E-mail: mdlogue@umich.edu, and Kushner, Mark J., E-mail: mjkush@umich.edu. Electron energy distributions and electron impact source functions in Ar/N{sub 2} inductively coupled plasmas using pulsed power. United States: N. p., 2015. Web. doi:10.1063/1.4904935.
Logue, Michael D., E-mail: mdlogue@umich.edu, & Kushner, Mark J., E-mail: mjkush@umich.edu. Electron energy distributions and electron impact source functions in Ar/N{sub 2} inductively coupled plasmas using pulsed power. United States. doi:10.1063/1.4904935.
Logue, Michael D., E-mail: mdlogue@umich.edu, and Kushner, Mark J., E-mail: mjkush@umich.edu. Wed . "Electron energy distributions and electron impact source functions in Ar/N{sub 2} inductively coupled plasmas using pulsed power". United States. doi:10.1063/1.4904935.
@article{osti_22412985,
title = {Electron energy distributions and electron impact source functions in Ar/N{sub 2} inductively coupled plasmas using pulsed power},
author = {Logue, Michael D., E-mail: mdlogue@umich.edu and Kushner, Mark J., E-mail: mjkush@umich.edu},
abstractNote = {In plasma materials processing, such as plasma etching, control of the time-averaged electron energy distributions (EEDs) in the plasma allows for control of the time-averaged electron impact source functions of reactive species in the plasma and their fluxes to surfaces. One potential method for refining the control of EEDs is through the use of pulsed power. Inductively coupled plasmas (ICPs) are attractive for using pulsed power in this manner because the EEDs are dominantly controlled by the ICP power as opposed to the bias power applied to the substrate. In this paper, we discuss results from a computational investigation of EEDs and electron impact source functions in low pressure (5–50 mTorr) ICPs sustained in Ar/N{sub 2} for various duty cycles. We find there is an ability to control EEDs, and thus source functions, by pulsing the ICP power, with the greatest variability of the EEDs located within the skin depth of the electromagnetic field. The transit time of hot electrons produced in the skin depth at the onset of pulse power produces a delay in the response of the EEDs as a function of distance from the coils. The choice of ICP pressure has a large impact on the dynamics of the EEDs, whereas duty cycle has a small influence on time-averaged EEDs and source functions.},
doi = {10.1063/1.4904935},
journal = {Journal of Applied Physics},
number = 4,
volume = 117,
place = {United States},
year = {Wed Jan 28 00:00:00 EST 2015},
month = {Wed Jan 28 00:00:00 EST 2015}
}
  • Cited by 2
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