Tunneling Model for Electron Transport and Its Temperature Dependence in Crystals of Low Carrier Mobility. Example: Anthracene

Abstract

A tunneling model is used to explain electron transport in crystals of low carrier mobility. Temperature is incorporated into the model by allowing the barrier width to vary sinusoidally as a result of lattice vibrations. The maximum amplitude of vibration is proportional to T^½. The resulting expression for the mobility exhibits a linear temperature dependence. The model can also be used to estimate the width of the conduction band. The calculated results are compared with experimental results on anthracene, and the agreement is quite good for the mobility but not as good for the temperature dependence.