Modeling the effect of top gate voltage on the threshold of a double gate organic field effect transistor

In this paper we have investigated theoretically the effect of top gate voltage on the threshold voltage of a double gate organic field effect transistor. We have solved the 1-D Poisson's equation in organic semiconductor active layer of this structure. Using the calculated local potential profile in the active layer, the total surface charge density was obtained. By considering the linear variation of this charge quantity with bottom gate voltage, the modulation of threshold voltage was studied as a function of different top gate voltages. It appears that the shielding effect of the top gate charges attenuates the effect of top gate voltage on the threshold voltage. In situations where shielding charges do not exist, the top gate voltage drastically affects the threshold voltage. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4754807]