Hole Mobility Studies on Thiophene-Based Conjugated Polymers Developed for Use in Organic Electronic Devices

In optimizing organic electronic devices, such as solar cells and field effect transistors, the mobility plays a crucial role affecting many aspects of performance, including: charge separation efficiencies, carrier densities, and drain currents. By fabricating hole-dominated devices and fitting the measured current-voltage characteristics to the field-dependent space-charge-limited mobility model we were able to measure hole mobilities in a set of conjugated polymers including p-Pt-BTD-Th, p-Pt-BTD-EDOT, and both regio-regular and regio-randem P3HT. These materials have been shown to exhibit promise as active layers in organic solar cells, light-emitting diodes, and field effect transistors. We present the results of these measurements and the effects induced by thermal annealing.