1D parallel plate discharge

Parallel plate discharge in argon using dual frequency excitation

We validated our PIC-MC implementation with that from Donko08¹ by comparing our results for a 1d3v simulated parallel plate discharge in argon. Hereby a dual frequency excitation is applied, i.e. a 13.56 MHz and a 27.12 MHz cosine signal is superposed with an amplitude of 315 volts.

Figure 1: Left: GMSH geometry model for the 1D simulation setup. Right: Applied voltage on powered (top) electrode.

Parameter	Setting	Unit
Argon pressure	0.2	[Torr]
Amplitude	315	[V]
Frequency	13.56 + 27.12	[MHz]
Electrode distance	6.5	[cm]
Electron time step	1e-11	[s]
Cell spacing	1 x 1 x 1	[mm3 ]
Charge weighting	1e6	[-]
Secondary electron yield	0.2 (> 0.1 to approximate electron reflection)	[-]
Electron reflection on wall	None	[-]
Electron energy partitioning	one-takes-it-all	[-]

Table 1: PIC-MC settings and simulation parameters used for the dual frequency discharge.

The results are nearly identical for both PIC-MC implementations, like seen for example in the ar+ hit histogram on the powered and grounded electrode, respectively. However, we had some discrepancies at first as we used a more simplified ar+ collision model as in Donko08. Thus, we adjusted our model to that of Donko08 using the more sophisticated ar+ collision model from Phelps.

Ar+ histogram from Donko08	Ar+ histogram from IST	Ar+ histogram from IST using simplified ar+ collision scheme

Figure 2: Ar+ hit histogram for different PIC-MC implementations and ar+ collision models, respectively.

Footnotes

1. Z. Donkó, PIC simulations of the separate control of ion flux and energy in CCRF discharges via the electrical asymmetry effec, 2008 ↩