Charge carrier transport in conducting polymers on the metal side of the metal-insulator transition: A review

The advances achieved in the field of the synthesis of conducting polymer films and the results of experimental investigations of the mechanism of charge carrier transport in heavily doped conducting polymer films on the metal side of the metal-insulator transition have been considered. The samples studied belong to the last generation of conducting polymers with a low degree of structural disorder, which makes it possible to dope samples to a highly conducting state characterized by an increased stability. Apart from the study of the morphology, structure, and doping conditions, the mechanism of low-temperature transport in these polymers has been investigated in detail. The results of investigations of the transport at low temperatures (T < 1 K) have been described, and a phenomenological model of charge carrier transfer in these systems has been proposed. The polymers under investigation have been widely used as injecting and accumulating layers in light-emitting organic diodes and solar cells.