A microscopic model for charge transfer between dielectric surfaces in dielectric barrier discharge plasmas

In field emission plasmas, electrons that initiate plasma come from the surface of a metallic electrode, or wall; emission is controlled by the workfunction of the wall, and computed via the Fowler-Nordheim formula. Impinging ions modify the rate of electron emission, which is accounted via the coefficient of secondary electron emission. However, in the case of dielectric surfaces, the microscopic mechanism by which electrons are emitted is not as well understood. Here we consider electron emission from dielectric surfaces in the context of dielectric barrier discharges. The configuration of interest consists of two parallel-plate metallic electrodes, each covered by a dielectric layer. We present a quantum mechanics based computation of the rates of charge transfer between dielectric surfaces, under moderate strength AC fields with frequencies in the kilohertz range. We compute the rate of charge transfer between surfaces, which is necessary condition, but not sufficient, for plasma formation. The microscopic model of electron transfer described here has potential applications in the design of micro and nano-scale plasma generators.