Temperature dependence of hopping transport in polymeric semiconductors

Abstract

We report the results of measurement and analysis of the electrical conductivity of two synthetic highly purified copolymers of the polyacene quinone radical (PAQR) type. The dc conductivity was examined as a function of temperature and pressure. The conductivity-pressure relation is observed to go as log σ versus P 1 2 . The conductivities under moderate pressure (400–5000 atm) show linear relationships on log σ versus T − 1 4 plots in the temperature range 70 K < T < 300 K. The possible interpretations as variable range hopping or as nearest neighbour hopping with distributions of activation energies are discussed.