Numerical investigation of dual frequency capacitively coupled hydrogen plasmas

Abstract

In this paper, a two-dimensional fluid model is used to investigate capacitively coupled hydrogen plasmas produced by a combination of two rf sources. We have tested the case when one electrode is simultaneously driven by the rf sources, as well as the case when two sources are connected to different electrodes. The results suggest that, according to the factor between the frequencies, either one or other configuration allows higher power coupling to the discharge. A simple analysis of the sheath dynamics is also performed. The simulations show an important modulation of the sheath width. In agreement with other analytical and numerical calculations, the results indicate that the amplitude of the modulation is stronger when the sheath thickness is small.

Modeling of Capacitively Coupled RF Plasmas in H2

“…Pioneering studies of this kind are those by Novikova et al16 and Kalache et al25 where 1D fluid models where coupled to a very simplified description of the vibrational energy reservoir. Neglecting the kinetics of molecules, a 2D fluid model was developed by Salabaş et al26 and recently applied to the study of dual frequency CC hydrogen plasmas 27…”

Hybrid simulation of a dc-enhanced radio-frequency capacitive discharge in hydrogen

“…Such chemical kinetics models played an important role in clarifying the hydrogen plasma chemistry, particularly by providing a quantitative account of the mechanisms of vibrational excitation, molecular dissociation, and ion production, but they were unable to account for the effects of space charge which are necessary in particular for a proper description of CCRF hydrogen discharges. As a result, models were developed coupling species transport and chemical reaction [7,[27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45]. These models varied in the type of formulation (kinetic, fluid or hybrid), the number of spatial dimensions, the degree of self-consistency, and the completeness of the chemical reaction scheme.…”

Phase-shift effect in capacitively coupled plasmas with two radio frequency or very high frequency sources

“…In the simulations, the density of background gas argon N is assumed to be constant, and the ion temperature T i is assumed being constant as room temperature. 3,5,9,11,22,23 The boundary conditions for ions and electrons are as follows ͑which is usually used in the fluid model, for example, Refs. 19.…”