Particle-in-cell simulations of the alpha and gamma modes in collisional nitrogen capacitive discharges
| Autor: | Emi Kawamura, Pascal Chabert, Allan J. Lichtenberg, Michael A. Lieberman |
|---|---|
| Přispěvatelé: | Laboratoire de Physique des Plasmas (LPP), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École polytechnique (X)-Sorbonne Université (SU)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) |
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
010302 applied physics
Materials science Capacitive sensing chemistry.chemical_element Alpha (ethology) Condensed Matter Physics 01 natural sciences Nitrogen 010305 fluids & plasmas chemistry [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph] 0103 physical sciences Particle-in-cell Atomic physics ComputingMilieux_MISCELLANEOUS |
| Zdroj: | Plasma Sources Science and Technology Plasma Sources Science and Technology, IOP Publishing, 2021, 30 (3), pp.035001. ⟨10.1088/1361-6595/abde22⟩ |
| ISSN: | 0963-0252 1361-6595 |
| Popis: | We perform one-dimensional (1D) particle-in-cell (PIC) simulations to study the α and γ modes in an intermediate pressure 1.6 Torr, 2.5 cm gap capacitive nitrogen discharge driven at 13.56 MHz with current density amplitudes J 0 = 7 to 150 A m−2. In the α-mode, ion-induced secondary electron emission has minimal effects on the discharge equilibrium, while in the γ-mode, it is essential for sustaining the discharge. As in a previous study of a comparable argon discharge, [Kawamura et al 2020, J. Vac. Sci. Technol. A 38, 023003], the nitrogen discharge in the α-mode can be described by a ‘passive bulk’ model in which the ionization is negligible in the central bulk region and is due solely to electron sheath heating. The nitrogen discharge undergoes an α to γ transition in the applied J 0 range, characterized by an increase in density and a decrease in electron temperature, sheath widths and sheath voltages. For the γ-mode, we calculate the scalings of the maximum sheath width s m and the rf sheath voltage amplitude V 1 with J 0. We compare the PIC results in the α-mode to the passive bulk model (modified for nitrogen), and, in the γ-mode with the expected J 0-V 1 and s m-V 1 curves. We find good agreement with the simulations in both the α and γ regimes, and the α to γ transition is well predicted by the models. |
| Databáze: | OpenAIRE |
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