Radial characterization of the electron energy distribution in a helicon source terminated by a double layer
Date
2008
Authors
Takahashi, Kazunori
Charles, Christine
Boswell, Rod
Hatakeyama, Rikizo
Journal Title
Journal ISSN
Volume Title
Publisher
American Institute of Physics (AIP)
Abstract
Electron energy probability functions (EEPFs) are measured across the radius (0 ≤ r < 6.85 cm) of
a low pressure (0.3 mTorr) helicon plasma source terminated by a current-free double layer. The
source field of about 130 G is generated using a Helmholtz coil pair and the radio frequency (rt)
power is maintained at 250 W. All EEPFs exhibit a distribution with a temperature Te bulk out to a
break energy ebreak and a relatively depleted distribution for higher energies with a lower
temperature Te tail· Te bulk and Te tail are about 8 eV and 5 eV, respectively, for r<4 cm and increase
up to about 14 eV and 9 eV near the source wall, i.e., near the rf antenna. ebreak is found to
correspond to the potential drop of the double layer for the central part of the source and to the
sheath potential near the wall.
Description
Keywords
Electron energy probability functions (EEPFs), radius (0 ≤ r < 6.85 cm), helicon plasma, low pressure (0.3 mTorr), Helmholtz coil, radio frequency (rt)
Citation
Collections
Source
Physics of Plasmas
Type
Journal article