A nanoparticulate indium tin oxide field-effect transistor with solid electrolyte gating

Reversible tuning of the transport properties of metallic conducting systems is not reported widely in the literature. Here, we report a junction field-effect transistor (FET) based on a transparent conducting oxide (TCO) nanoparticle channel and a solid polymer electrolyte as a gate. The device principle is based on the variation of the drain current induced by the capacitive double layer charging at the electrolyte/nanoparticle interfaces. A device with a metallic conducting channel made of indium tin oxide (ITO) nanoparticles exhibits an on/off ratio of 2 x 10(3) even when the gate potential is limited within the electrochemical capacitive region to avoid redox reactions at the interface. An FET device with metal-like conductance is always favored for the low dimensions of the device and a high on-state current. The field-effect mobility is calculated to be 24.3 cm(2) V(-1) s(-1). A subthreshold swing between 230 and 425 mV dec(-1) is observed.