The mechanism of metal conductivity over the interface between organic insulators

The hopping mobility of charge carriers (both at the surface and in the bulk) is analyzed theoretically in the presence of electron-hole pairs. A physical model is suggested for the metal conductivity over the interface between organic materials, each being an insulator by itself. The conductivity is due to the rather high surface density of geminate pairs formed at the interface. Conditions are established wherein the transitions of a significant portion of charge carriers between molecules do not require thermal activation or tunneling. The surface conductivity and mobility of charge carriers are estimated by numerical simulation.