skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Nickel atom and ion densities in an inductively coupled plasma with an internal coil

Abstract

The nickel atom density was measured in an inductively coupled argon plasma with an internal Ni coil, as a function of pressure and power, using optical absorption spectroscopy. Nickel atoms were sputtered from the coil and from a separate Ni target under optional target bias. A fraction of the atoms was ionized in the high-density plasma. The gas temperature was determined by analyzing the rovibrational spectra of the second positive system of nitrogen actinometer gas. The electron density was determined by optical emission spectroscopy in combination with a global model. For a pressure of 8-20 mTorr and coil power of 40-200 W, the Ni atom density ranged from 2.7x10{sup 9} to 1.5x10{sup 10} cm{sup -3}, increasing strongly with pressure. The Ni atom density first increased with power but saturated at high power levels. The measured Ni atom density agreed fairly well with the predictions of a global model, in particular, at the higher pressures. The model also predicted that the Ni{sup +} ion density greatly increased at higher powers and pressures. Applying 70 W bias on the target electrode increased the Ni atom density by 60%.

Authors:
; ; ;  [1];  [2];  [3]
  1. Plasma Processing Laboratory, Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204-4004 (United States)
  2. (France)
  3. (United States)
Publication Date:
OSTI Identifier:
20884960
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 1; Other Information: DOI: 10.1063/1.2401659; (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; ABSORPTION SPECTROSCOPY; ARGON; ELECTRODES; ELECTRON DENSITY; ELECTRON TEMPERATURE; EMISSION SPECTROSCOPY; ION DENSITY; IONIZATION; NICKEL; NICKEL IONS; NITROGEN; PLASMA; PLASMA DENSITY; PLASMA DIAGNOSTICS; PRESSURE DEPENDENCE; PRESSURE RANGE PA

Citation Formats

Xu Lin, Sadeghi, Nader, Donnelly, Vincent M., Economou, Demetre J., Laboratoire de Spectrometrie Physique, University Joseph Fourier-Grenoble and CNRS, 38042, Grenoble, and Plasma Processing Laboratory, Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204-4004. Nickel atom and ion densities in an inductively coupled plasma with an internal coil. United States: N. p., 2007. Web. doi:10.1063/1.2401659.
Xu Lin, Sadeghi, Nader, Donnelly, Vincent M., Economou, Demetre J., Laboratoire de Spectrometrie Physique, University Joseph Fourier-Grenoble and CNRS, 38042, Grenoble, & Plasma Processing Laboratory, Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204-4004. Nickel atom and ion densities in an inductively coupled plasma with an internal coil. United States. doi:10.1063/1.2401659.
Xu Lin, Sadeghi, Nader, Donnelly, Vincent M., Economou, Demetre J., Laboratoire de Spectrometrie Physique, University Joseph Fourier-Grenoble and CNRS, 38042, Grenoble, and Plasma Processing Laboratory, Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204-4004. Mon . "Nickel atom and ion densities in an inductively coupled plasma with an internal coil". United States. doi:10.1063/1.2401659.
@article{osti_20884960,
title = {Nickel atom and ion densities in an inductively coupled plasma with an internal coil},
author = {Xu Lin and Sadeghi, Nader and Donnelly, Vincent M. and Economou, Demetre J. and Laboratoire de Spectrometrie Physique, University Joseph Fourier-Grenoble and CNRS, 38042, Grenoble and Plasma Processing Laboratory, Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204-4004},
abstractNote = {The nickel atom density was measured in an inductively coupled argon plasma with an internal Ni coil, as a function of pressure and power, using optical absorption spectroscopy. Nickel atoms were sputtered from the coil and from a separate Ni target under optional target bias. A fraction of the atoms was ionized in the high-density plasma. The gas temperature was determined by analyzing the rovibrational spectra of the second positive system of nitrogen actinometer gas. The electron density was determined by optical emission spectroscopy in combination with a global model. For a pressure of 8-20 mTorr and coil power of 40-200 W, the Ni atom density ranged from 2.7x10{sup 9} to 1.5x10{sup 10} cm{sup -3}, increasing strongly with pressure. The Ni atom density first increased with power but saturated at high power levels. The measured Ni atom density agreed fairly well with the predictions of a global model, in particular, at the higher pressures. The model also predicted that the Ni{sup +} ion density greatly increased at higher powers and pressures. Applying 70 W bias on the target electrode increased the Ni atom density by 60%.},
doi = {10.1063/1.2401659},
journal = {Journal of Applied Physics},
number = 1,
volume = 101,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
  • The effect of magnetic filtering on the electron energy distribution function is studied in an inductive discharge with internal coil coupling. The coil is placed inside the plasma and driven by a low-frequency power supply (5.8 MHz) which leads to a very high power transfer efficiency. A permanent dipole magnet may be placed inside the internal coil to produce a static magnetic field around 100 Gauss. The coil and the matching system are designed to minimize the capacitive coupling to the plasma. Capacitive coupling is quantified by measuring the radiofrequency (rf) plasma potential with a capacitive probe. Without the permanentmore » magnet, the rf plasma potential is significantly smaller than the electron temperature. When the magnet is present, the rf plasma potential increases. The electron energy distribution function is measured as a function of space with and without the permanent magnet. When the magnet is present, electrons are cooled down to low temperature in the downstream region. This region of low electron temperature may be useful for plasma processing applications, as well as for efficient negative ion production.« less
  • Measured relative densities as a function of O{sub 2} addition in a CH{sub 3}F/O{sub 2} inductively coupled plasma changed abruptly for H, O, and particularly F atoms (factor of 4) at 48% O{sub 2}. A corresponding transition was observed in electron density, effective electron temperature, and gas temperature, as well as in C, CF, and CH optical emission. These abrupt transitions were attributed to the reactor wall reactivity, changing from a polymer-coated surface to a polymer-free surface and vice-versa, as the O{sub 2} content in the feed gas crossed 48%.
  • The authors have developed a new inductively coupled plasma source (ICPS), using a multispiral coil with 1/3 the inductance of the conventional ICPS coil. This source can produce plasma of 10{sup 11} cm{sup {minus}3} or higher density with {plus_minus}5% fluctuation, at pressures below 10 mTorr. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.
  • The radial distributions of the electron density and the relative atomic argon excited state density have been investigated by means of Langmuir probes and optical emission spectroscopy, respectively, in planar inductively coupled plasmas. The plasma source is a modified Gaseous Electronics Conference RF Reference Cell [P. J. Hargis {ital et al.}, Rev. Sci. Instrum. {bold 65}, 140 (1994)]. Two different planar coil geometries, a five-turn spiral coil and a one-turn circular coil, were investigated for a variety of plasma parameters. Additionally, we investigated the effect of different powering configurations of the spiral coil and an electrostatic shield between the coilmore » and the plasma. We found that the coil geometry and power configuration of the coil influences the radial distribution of the electron density in the region close to the coil only, while in the region close to the lower electrode the radial distribution is dominated by diffusion. {copyright} {ital 1997} {ital The American Physical Society}« less