Charge carrier extraction dynamics for organic field effect transistor structures

We present experimental data and a model for charge carrier extraction from the channel of a device structure resembling an organic field effect transistor. The initially accumulated channel is depleted by a sudden change of the gate voltage. The measured discharge current transient decreases either as a power law or exponentially if the final state of the channel is completely or partially depleted, respectively. The extraction process is modeled with a capacitor/resistor circuit with a time-dependent resistance that increases with decreasing channel carrier density. Analytical and numerical results are discussed and compared with the experimental data. (C) 2011 American Institute of Physics. [doi:10.1063/1.3625945]