All-solid-state electric-double-layer transistor based on oxide ion migration in Gd-doped CeO2 on SrTiO3 single crystal

Abstract

An all-solid-state electric-double-layer transistor (EDLT) with a Gd-doped CeO2 (GDC) oxide ion conductor/SrTiO3 (STO) insulator structure has been developed. At 473 K, the drain current of the EDLT was well controlled, from less than nA order to μA order, by electrostatic carrier doping at the GDC/STO interface due to oxide ion (O2−) migration in the GDC, in contrast to an inactiveness at room temperature. The EDL capacitance at the interface, measured with an ac impedance spectroscopy, was 14 μF cm−2, higher than that reported for a microporous-SiO2 EDLT and comparable to that of an ionic-liquid-gated EDLT.