Diagnostics of an inductively coupled plasma in oxygen

Masahiro Tadokoro, Akihiko Itoh, Nobuhiko Nakano, Zoran Lj, Toshiaki Makabe

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

-Spatial time-integrated and space-time resolved proflies of excited atoms of oxygen were measured by optical emission spectroscopy for inductively coupled plasma (ICP) in oxygen. Discharge was sustained by a single turn coil supplied by 13.56 MHz RF generator delivering 100 and 200 W of power. The spatial emission profiles give the anatomy of the discharge required in order to understand the basic kinetics of ICP. Two types of nonuniformities are observed, azimuthal anisotropy and radial nonuniformity, both caused by spatially dependent energy supply to the electrons. Our experimental results show that oxygen is much more affected by azimuthal anisotropy and radial nonuniformity than argon. It is due to a different role of metastable atoms in kinetics of excitation, whereby stepwise excitation in oxygen is less probable than in argon. Optical emission data are supplemented by Langmuir probe measurements of electron densities and plasma potentials. Electrons gain energy from the time varying fields close to the coil, and the energy is not redistributed along the radius before it is dissipated in excitation, thus the observations are not consistent with the nonlocal theory predictions for the range of pressures, geometry, and power covered in this paper.

Original languageEnglish
Pages (from-to)1724-1732
Number of pages9
JournalIEEE Transactions on Plasma Science
Volume26
Issue number6
DOIs
Publication statusPublished - 1998

Fingerprint

nonuniformity
oxygen
coils
argon
excitation
anisotropy
metastable atoms
plasma potentials
anatomy
kinetics
optical emission spectroscopy
electrostatic probes
light emission
energy
electrons
generators
radii
profiles
geometry
predictions

Keywords

  • CT image
  • Inductively coupled plasma
  • Plasma ashing
  • Plasma diagnostics
  • Radon inversion

ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Condensed Matter Physics

Cite this

Diagnostics of an inductively coupled plasma in oxygen. / Tadokoro, Masahiro; Itoh, Akihiko; Nakano, Nobuhiko; Lj, Zoran; Makabe, Toshiaki.

In: IEEE Transactions on Plasma Science, Vol. 26, No. 6, 1998, p. 1724-1732.

Research output: Contribution to journalArticle

Tadokoro, Masahiro ; Itoh, Akihiko ; Nakano, Nobuhiko ; Lj, Zoran ; Makabe, Toshiaki. / Diagnostics of an inductively coupled plasma in oxygen. In: IEEE Transactions on Plasma Science. 1998 ; Vol. 26, No. 6. pp. 1724-1732.
@article{e5254cc5355f467ca08ceb047fc66f9a,
title = "Diagnostics of an inductively coupled plasma in oxygen",
abstract = "-Spatial time-integrated and space-time resolved proflies of excited atoms of oxygen were measured by optical emission spectroscopy for inductively coupled plasma (ICP) in oxygen. Discharge was sustained by a single turn coil supplied by 13.56 MHz RF generator delivering 100 and 200 W of power. The spatial emission profiles give the anatomy of the discharge required in order to understand the basic kinetics of ICP. Two types of nonuniformities are observed, azimuthal anisotropy and radial nonuniformity, both caused by spatially dependent energy supply to the electrons. Our experimental results show that oxygen is much more affected by azimuthal anisotropy and radial nonuniformity than argon. It is due to a different role of metastable atoms in kinetics of excitation, whereby stepwise excitation in oxygen is less probable than in argon. Optical emission data are supplemented by Langmuir probe measurements of electron densities and plasma potentials. Electrons gain energy from the time varying fields close to the coil, and the energy is not redistributed along the radius before it is dissipated in excitation, thus the observations are not consistent with the nonlocal theory predictions for the range of pressures, geometry, and power covered in this paper.",
keywords = "CT image, Inductively coupled plasma, Plasma ashing, Plasma diagnostics, Radon inversion",
author = "Masahiro Tadokoro and Akihiko Itoh and Nobuhiko Nakano and Zoran Lj and Toshiaki Makabe",
year = "1998",
doi = "10.1109/27.747892",
language = "English",
volume = "26",
pages = "1724--1732",
journal = "IEEE Transactions on Plasma Science",
issn = "0093-3813",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
number = "6",

}

TY - JOUR

T1 - Diagnostics of an inductively coupled plasma in oxygen

AU - Tadokoro, Masahiro

AU - Itoh, Akihiko

AU - Nakano, Nobuhiko

AU - Lj, Zoran

AU - Makabe, Toshiaki

PY - 1998

Y1 - 1998

N2 - -Spatial time-integrated and space-time resolved proflies of excited atoms of oxygen were measured by optical emission spectroscopy for inductively coupled plasma (ICP) in oxygen. Discharge was sustained by a single turn coil supplied by 13.56 MHz RF generator delivering 100 and 200 W of power. The spatial emission profiles give the anatomy of the discharge required in order to understand the basic kinetics of ICP. Two types of nonuniformities are observed, azimuthal anisotropy and radial nonuniformity, both caused by spatially dependent energy supply to the electrons. Our experimental results show that oxygen is much more affected by azimuthal anisotropy and radial nonuniformity than argon. It is due to a different role of metastable atoms in kinetics of excitation, whereby stepwise excitation in oxygen is less probable than in argon. Optical emission data are supplemented by Langmuir probe measurements of electron densities and plasma potentials. Electrons gain energy from the time varying fields close to the coil, and the energy is not redistributed along the radius before it is dissipated in excitation, thus the observations are not consistent with the nonlocal theory predictions for the range of pressures, geometry, and power covered in this paper.

AB - -Spatial time-integrated and space-time resolved proflies of excited atoms of oxygen were measured by optical emission spectroscopy for inductively coupled plasma (ICP) in oxygen. Discharge was sustained by a single turn coil supplied by 13.56 MHz RF generator delivering 100 and 200 W of power. The spatial emission profiles give the anatomy of the discharge required in order to understand the basic kinetics of ICP. Two types of nonuniformities are observed, azimuthal anisotropy and radial nonuniformity, both caused by spatially dependent energy supply to the electrons. Our experimental results show that oxygen is much more affected by azimuthal anisotropy and radial nonuniformity than argon. It is due to a different role of metastable atoms in kinetics of excitation, whereby stepwise excitation in oxygen is less probable than in argon. Optical emission data are supplemented by Langmuir probe measurements of electron densities and plasma potentials. Electrons gain energy from the time varying fields close to the coil, and the energy is not redistributed along the radius before it is dissipated in excitation, thus the observations are not consistent with the nonlocal theory predictions for the range of pressures, geometry, and power covered in this paper.

KW - CT image

KW - Inductively coupled plasma

KW - Plasma ashing

KW - Plasma diagnostics

KW - Radon inversion

UR - http://www.scopus.com/inward/record.url?scp=0032312254&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0032312254&partnerID=8YFLogxK

U2 - 10.1109/27.747892

DO - 10.1109/27.747892

M3 - Article

VL - 26

SP - 1724

EP - 1732

JO - IEEE Transactions on Plasma Science

JF - IEEE Transactions on Plasma Science

SN - 0093-3813

IS - 6

ER -