Titill: | On singlet metastable states, ion flux and ion energy in single and dual frequency capacitively coupled oxygen discharges |
Höfundur: |
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Útgáfa: | 2017-03-27 |
Tungumál: | Enska |
Umfang: | 175201 |
Háskóli/Stofnun: | Háskóli Íslands University of Iceland |
Svið: | Verkfræði- og náttúruvísindasvið (HÍ) School of Engineering and Natural Sciences (UI) |
Deild: | Raunvísindastofnun (HÍ) Science Institute (UI) |
Birtist í: | Journal of Physics D: Applied Physics;50(17) |
ISSN: | 0022-3727 1361-6463 (eISSN) |
DOI: | 10.1088/1361-6463/aa65ed |
Efnisorð: | Capactively coupled discharge; Oxygen; Particle-in-cell/Monte Carlo collisions; Efnafræði; Súrefni; Rafeindir |
URI: | https://hdl.handle.net/20.500.11815/614 |
Tilvitnun:Hannesdottir, H., & Gudmundsson, J. T. (2017). On singlet metastable states, ion flux and ion energy in single and dual frequency capacitively coupled oxygen discharges. Journal of Physics D: Applied Physics, 50(17), 175201. doi:10.1088/1361-6463/aa65ed
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Útdráttur:We apply particle-in-cell simulations with Monte Carlo collisions to study the influence of the
singlet metastable states on the ion energy distribution in single and dual frequency capacitively
coupled oxygen discharges. For this purpose, the one-dimensional object-oriented particlein-cell
Monte Carlo collision code oopd1 is used, in which the discharge model includes the
following nine species: electrons, the neutrals O(3
P) and O ( Σ− 2 X g
3 ), the negative ions O−, the
positive ions O+ and O+
2 , and the metastables O(1
D), O2( ) a ∆g
1 and O2(b Σ+
g
1 ). Earlier, we have
explored the effects of adding the species O2(a ∆g
1 ) and O2(b Σ+
g
1 ), and an energy-dependent
secondary electron emission yield for oxygen ions and neutrals, to the discharge model. We
found that including the two molecular singlet metastable states decreases the ohmic heating and
the effective electron temperature in the bulk region (the electronegative core). Here we explore
how these metastable states influence dual frequency discharges consisting of a fundamental
frequency and the lowest even harmonics. Including or excluding the detachment reactions of the
metastables O2(a ∆g
1 ) and O2(b Σ+
g
1 ) can shift the peak electron temperature from the grounded
to the powered electrode or vice versa, depending on the phase difference of the two applied
frequencies. These metastable states can furthermore significantly influence the peak of the ion
energy distribution for O+
2 -ions bombarding the powered electrode, and hence the average ion
energy upon bombardment of the electrode, and lower the ion flux.
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Leyfi:Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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