PEDOT-PSS nanoribbon and cast film field effect transistors with ferroelectric gating

Abstract

Poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonic acid) – PEDOT-PSS was electro-spun to produce high aspect ratio nano-ribbons. Individual nano-ribbons and cast films of varying thicknesses were electrically characterized in a field effect transistor configuration with ferroelectric poly(vinylidene fluoride-trifluoroethylene)-PVDF-TrFE as the gate insulator. The devices showed p-type behavior consistent with hole transport, and a ferroelectric memory effect. Thinner films exhibited stronger field effect compared to thicker films. As the thicknesses increased, relative changes in the gate induced currents decreased, while the threshold voltage and memory window width increased. The mobility was ∼0.5 cm2/V-s and the induced charge density was 2.3 x 1018/cm2 for the 10nm film device. A simple application of non-volatile charge storage was demonstrated via the use of ± 50V erase/write pulses applied to the gate. The device operated successfully with no degradation in the write/erase functionality, and is the first demonstrating a ferroelectric field effect in PEDOT-PSS thin films.