Control of threshold voltage of organic field-effect transistors with double-gate structures

We fabricated pentacene field-effect transistors with planar-type double-gate structures, where the top- and bottom-gate electrodes can independently apply voltage biases to channel layers. The threshold voltage of organic transistors is changed systematically in a wide range from -16 to -43 V when the voltage bias of the top-gate electrode is changed from 0 to +60 V. The mobility in the linear regime is almost constant (0.2 cm(2)/V s) at various voltage biases of the top-gate electrode and the on/off ratio is 10(6). (c) 2005 American Institute of Physics.