Double-gate organic field-effect transistor

We present a novel double-gate structure for polymeric field-effect transistors produced from a solution of [9,9]-dioctylfluorene-co-bithiophene copolymer (F8T2) as the p-type organic semiconductor. The double-gate geometry adapts to different bias configurations and shows improved performances and higher flexibility of operation with respect to single-gate devices. The device characteristics show an increased on/off ratio and demonstrate the possibility to control the threshold voltage as well as the off current. The maximum hole mobility of 8×10−2cm2∕Vs measured for the F8T2 layer, in combination with the features of the double-gate structure, suggest the possibility to produce optimized devices with very high performances.