Modeling characteristics of nonequilibrium processes during breakdown of capacitive rf argon glow discharge

A self-consistent, diffusion-drift approximated fluid model including ion and electron continuity equations and an electron energy equation is presented for simulating the nonequilibrium characteristics during breakdown of argon rf glow discharge. The nonlinear partial differential equations of the model are solved numerically by using a so-called finite volume method. The numerical results indicate that there exist two different phases on the breakdown curves, i.e., the low p⋅d phase and high p⋅d phase. The breakdown voltage, analyzed for three different gaps, varies little in low p⋅d phase while in the high p⋅d phase, it increases linearly with pressure increase. Time evolution of Ohmic heating and energy loss during breakdown are presented in detail. Analysis yields that the heating mechanisms are the dominant factors in breakdown. Moreover, the steady discharge characteristics are also studied specifically under breakdown voltage of 10Torr. The charged particle densities are on the order of 1015∕m3 and the electron energy has two characteristic values at different rf phases.