Self-consistent kinetic simulations of inductively coupled low-pressure discharges

Abstract

Summary form only given. A self-consistent system of equations is presented for the kinetic description of nonlocal, non-uniform, nearly collisionless plasmas of low-pressure discharges. In low-pressure discharges, where the electron mean free path is larger than or comparable to the discharge length, the electron dynamics is essentially nonlocal. Moreover, the electron energy distribution function (EEDF) deviates considerably from a Maxwellian. Therefore, an accurate kinetic description of the low-pressure discharges requires knowledge of the nonlocal conductivity operator and calculation of the non-Maxwellian EEDF. The previous treatments made use of simplifying assumptions: a uniform density profile and a Maxwellian EEDF. In the present study we derive a self-consistent system of equations for the kinetic description of nonlocal, non-uniform, nearly collisionless plasmas of low-pressure. The system consists of a nonlocal conductivity operator, and an averaged over fast electron bounce motions kinetic equation for the EEDF. A fast Fourier transform method was applied to speed up the numerical simulations. The importance of accounting for the non-uniform plasma density profile for computing the current density profile and the EEDF is demonstrated. Effects of plasma non-uniformity on electron heating in the rf electric field were also studied. An enhancement of the electron heating due to the bounce resonance between the electron bounce motion and the rf electric field has been observed.