Dispersion Relation and General Charge-Transport Model for Organic Semiconductors

Although organic semiconductors have been widely applied in many fields, their charge-transport mechanism has not been definitively confirmed. A dispersion relation is proposed herein for organic semiconductors, and the corresponding density of states (DOS) derived. The derived DOS can model experimental data for typical materials. The dispersion relation is combined with a general transport model based on the Boltzmann transport equation and considering the transport edge, then main transport properties can be evaluated. The numerical results for mobility versus carrier density and Seebeck coefficient versus conductivity are in good agreement with experimental data.