Numerical study of a direct current plasma sheath based on kinetic theory

A fully kinetic theory model was developed to study plasma properties of the sheath of a direct current glow discharge. This model includes a direct numerical solution of the Boltzmann equations for electron and ion distribution functions with a self-consistent electric field obtained from the Poisson equation. The calculated profiles of density, drift velocity, temperature, and electric potential were used to show the structure of the plasma sheath. The results of the direct numerical solution were compared with a particle-in-cell Monte Carlo simulation. It was also demonstrated that for a small Debye length to the ion mean-free path ratio, results obtained using the continuum sheath model, which includes two parameters, can be matched to the kinetic theory simulations.