Emission Limited Current in Low-Mobility Solids

Results of computer-calculated solutions of a set of equations describing emission-limited currents (ELC) in low-mobility solids are presented. The continuity of current equation with electric field-dependent mobility is used to calculate the field dependence of ELC under various injection conditions. Its shape and steepness are found to change strongly with decreasing scattering length of injected carriers, approaching the standard description of the one-dimensional Onsager model with field-independent mobility. The recombination of the charge carriers at the contact is shown to reduce the current without remarkable change of its functional dependence on practically accessible electric fields.