Boundary Effects in Solution of Boltzmann's Equation for Electron Swarms

Abstract

The combined effect of interaction of electrons with walls, neutral molecules and an electrostatic field is considered through analytic solution of Boltzmann's equation. In the first instance, we discuss a half-range decomposition in velocity space, corresponding to electrons moving to and from the walls, which is valid for all types of electron-molecule interactions. The half-range equations are solved in the steady state for zero field and the constant mean free path model, and it is shown that the familiar full-range 'two-term' approximation equations are adequate in this case, as far as estimating bulk properties of the electrons is concerned. For the nonzero field, again in the steady state, the full-range equations are solved for the constant collision frequency model.