Kinetic interpretation of resonance phenomena in low pressure capacitively coupled radio frequency plasmas

Sebastian Wilczek, Jan Trieschmann, Denis Eremin, Ralf Peter Brinkmann, Julian Schulze, Edmund Schuengel, Aranka Derzsi, I. Korolov, Peter Hartmann, Z. Donkó, Thomas Mussenbrock

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Low pressure capacitive radio frequency (RF) plasmas are often described by equivalent circuit models based on fluid approaches that predict the self-excitation of resonances, e.g., high frequency oscillations of the total current in asymmetric discharges, but do not provide a kinetic interpretation of these effects. In fact, they leave important questions open: How is current continuity ensured in the presence of energetic electron beams generated by the expanding sheaths that lead to a local enhancement of the conduction current propagating through the bulk? How do the beam electrons interact with cold bulk electrons? What is the kinetic origin of resonance phenomena? Based on kinetic simulations, we find that the energetic beam electrons interact with cold bulk electrons (modulated on a timescale of the inverse local electron plasma frequency) via a time dependent electric field outside the sheaths. This electric field is caused by the electron beam itself, which leaves behind a positive space charge, that attracts cold bulk electrons towards the expanding sheath. The resulting displacement current ensures current continuity by locally compensating the enhancement of the conduction current. The backflow of cold electrons and their interaction with the nonlinear plasma sheath cause the generation of multiple electron beams during one phase of sheath expansion and contribute to a strongly non-sinusoidal RF current. These kinetic mechanisms are the basis for a fundamental understanding of the electron power absorption dynamics and resonance phenomena in such plasmas, which are found to occur in discharges of different symmetries including perfectly symmetric plasmas.

Original languageEnglish
Article number063514
JournalPhysics of Plasmas
Volume23
Issue number6
DOIs
Publication statusPublished - Jun 1 2016

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radio frequencies
low pressure
sheaths
kinetics
electron beams
electrons
continuity
self excitation
conduction
plasma sheaths
electric fields
augmentation
plasma frequencies
electron plasma
equivalent circuits
leaves
space charge
oscillations
expansion
causes

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Wilczek, S., Trieschmann, J., Eremin, D., Brinkmann, R. P., Schulze, J., Schuengel, E., ... Mussenbrock, T. (2016). Kinetic interpretation of resonance phenomena in low pressure capacitively coupled radio frequency plasmas. Physics of Plasmas, 23(6), [063514]. https://doi.org/10.1063/1.4953432

Kinetic interpretation of resonance phenomena in low pressure capacitively coupled radio frequency plasmas. / Wilczek, Sebastian; Trieschmann, Jan; Eremin, Denis; Brinkmann, Ralf Peter; Schulze, Julian; Schuengel, Edmund; Derzsi, Aranka; Korolov, I.; Hartmann, Peter; Donkó, Z.; Mussenbrock, Thomas.

In: Physics of Plasmas, Vol. 23, No. 6, 063514, 01.06.2016.

Research output: Contribution to journalArticle

Wilczek, S, Trieschmann, J, Eremin, D, Brinkmann, RP, Schulze, J, Schuengel, E, Derzsi, A, Korolov, I, Hartmann, P, Donkó, Z & Mussenbrock, T 2016, 'Kinetic interpretation of resonance phenomena in low pressure capacitively coupled radio frequency plasmas', Physics of Plasmas, vol. 23, no. 6, 063514. https://doi.org/10.1063/1.4953432
Wilczek S, Trieschmann J, Eremin D, Brinkmann RP, Schulze J, Schuengel E et al. Kinetic interpretation of resonance phenomena in low pressure capacitively coupled radio frequency plasmas. Physics of Plasmas. 2016 Jun 1;23(6). 063514. https://doi.org/10.1063/1.4953432
Wilczek, Sebastian ; Trieschmann, Jan ; Eremin, Denis ; Brinkmann, Ralf Peter ; Schulze, Julian ; Schuengel, Edmund ; Derzsi, Aranka ; Korolov, I. ; Hartmann, Peter ; Donkó, Z. ; Mussenbrock, Thomas. / Kinetic interpretation of resonance phenomena in low pressure capacitively coupled radio frequency plasmas. In: Physics of Plasmas. 2016 ; Vol. 23, No. 6.
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