Effect of trap position on the electrical properties of unipolar organic semiconductor devices

We investigated the electrical properties of a unipolar organic device by intentionally inserting traps at specific positions within the device. Our findings demonstrate that the trap position has a considerable impact on the charge distribution, electric field, and charge transport behavior of the device. In particular, when the traps are positioned closer to a charge-injection electrode, the organic layer containing the traps experiences more significant band bending, resulting in a higher charge injection barrier. We propose an electrical model that fully explains the observed changes in the electrical properties of the device as a function of trap position.