Meyer-Neldel rule in fullerene field-effect transistors

The temperature dependence of the field-effect mobility is investigated in vacuum evaporated C-60-based organic field-effect transistors. The results show a thermally activated behavior with an activation energy that depends on the field-induced charge carrier density in the transistor channel. Upon extrapolation of the data in an Arrhenius plot we find an empirical relation, termed the Meyer-Neldel rule, which states that the mobility prefactor increases exponentially with the activation energy. Based on this analysis a characteristic temperature is extracted. The possible implications of this observation in terms of charge transport in fullerene-based field-effect transistors are discussed.