Organic/inorganic interfaced field-effect transistor properties with a novel organic semiconducting material

Abstract

A novel 1,3,4-oxadiazole-substituted benzo[b]triphenylene was synthesized by three-step synthetic procedure and OFET device design was successfully designed after theoretical calculations made using Gaussian software. For investigating the field-effect properties of designed organic electronic device, a SiO2 (300nm) was thermally grown on p-Si wafer at 1000 degrees C as a dielectric layer and gate, source and drain contacts have been deposited using Au metal with physical vapour deposition. 1,3,4-Oxadiazole-substituted benzo[b]triphenylene was spin coated on the source and drain electrodes of our device, forming organic/inorganic interfaced field-effect transistors. Surface morphology and thin film properties were investigated using AFM. All electrical measurements were done in air ambient. The device showed a typical p-type channel behaviour with increasing negative gate bias voltage values. Our results have surprisingly shown that the saturation regime of this device has high mobility (mu(FET)), excellent on/off ratio (I-on/I-off), high transconductance (g(m)) and a small threshold voltage (V-Th). The values of mu(FET), I-on/I-off, g(m) and V-Th were found as 5.02cm(2)/Vs, 0.7x10(3), 5.64 mu S/mm and 1.37V, respectively. These values show that our novel organic material could be a potential candidate for organic electronic device applications in the future.