Ultralow contact resistance in electrolyte-gated organic thin film transistors

We show that the parasitic contact resistance in staggered organic thin film transistors employing a solid electrolyte as the gate dielectric is around R(C) = 10 Omega cm, two orders of magnitude lower than in conventional devices. Moreover, this parameter is only weakly dependent on the thickness of the semiconductor and on the nature of the metal/semiconductor pair. This unique feature of an electrolyte-gated transistor results from the electrochemical doping of the active layer occurring under the influence of the applied gate bias. (C) 2010 American Institute of Physics. [doi:10.1063/1.3518075]