Ambipolar field-effect transistor characteristics of (BEDT-TTF)(TCNQ) crystals and metal-like conduction induced by a gate electric field

Ambipolar carrier conduction has been observed in a metal-insulator-semiconductor field-effect transistor made using (BEDT-TTF)(TCNQ) crystals. The temperature dependence of the source current with the applied positive gate voltage exhibits metal-like behavior at around room temperature. The metal-like conduction transforms into thermal-activation-type behavior below 240 K. The I-S-V-DS curve for an applied gate voltage of 80 V exhibited a corresponding change in the curvature below 240 K.