Electron heating modes and frequency coupling effects in dual-frequency capacitive CF₄plasmas

• Autorzy: Aranka Derzsi , Edmund Schüngel , Zoltán Donkó , Julian Schulze
• Języki publikacji: EN

Abstrakty

EN

Two types of capacitive dual-frequency discharges, used in plasma processing applications to achieve the separate control of the ion flux, Гi, and the mean ion energy, , at the electrodes, operated in CF4, are investigated by particle-in-cell simulations: (i) In classical dual-frequency discharges, driven by significantly different frequencies (1.937 MHz + 27.12 MHz), and Гi are controlled by the voltage amplitudes of the low-frequency and high-frequeny components, ΦLF and ΦHF, respectively. (ii) In electrically asymmetric (EA) discharges, operated at a fundamental frequency and its second harmonic (13.56 MHz + 27.12 MHz), ΦLF and ΦHF control Гi, whereas the phase shift between the driving frequencies, θ, is varied to adjust . We focus on the effect of changing the control parameter for on the electron heating and ionization dynamics and on Гi. We find that in both types of dual-frequency strongly electronegative discharges, changing the control parameter results in a complex effect on the electron heating and ionization dynamics: in classical dual-frequency discharges, besides the frequency coupling affecting the sheath expansion heating, additional frequency coupling mechanisms influence the electron heating in the plasma bulk and at the collapsing sheath edge; in EA dual-frequency discharges the electron heating in the bulk results in asymmetric ionization dynamics for values of θ around 45°, i.e., in the case of a symmetric applied

Słowa kluczowe

EN

dual-frequency RF discharges; electronegative plasmas; electrical asymmetry effect; frequency-coupling effects; electron heating modes

• Czasopismo: Open Chemistry
• Rocznik: 2015
• Tom: 13
• Numer: 1

Daty

otrzymano

2014-01-31

zaakceptowano

2014-04-03

online

2014-12-09

Twórcy

autor

Aranka Derzsi

• Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences,
  1121 Budapest, Hungary

autor

Edmund Schüngel

• Department of Physics, West Virginia University, Morgantown, WV 26506, USA

autor

Zoltán Donkó

• Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences,
  1121 Budapest, Hungary

autor

Julian Schulze

• Department of Physics, West Virginia University, Morgantown, WV 26506, USA

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Identyfikatory

DOI

10.1515/chem-2015-0044