Impact Of Device Structure On Field Dependence Of Carrier Mobility

In this study, we have used the impedance measurement to investigate the carrier transport in different diode structures fabricated with a well characterized organic hole transport material, m-MTDATA. It is demonstrated that the carrier injection level can be controlled by properly designing the device structures. In such devices, the field dependence of carrier mobility is observed to be very different since the injected carriers experienced distinct disordered during the transport due to varying carrier injection level. With a proper control of the device structure, the field dependence is observed to have negative P-F coefficient for carriers injected into high energy transport states. Finally, all the transport parameters involved in the classical Gaussian Disorder Model is derived successfully under certain assumption.