High-performance flexible organic field-effect transistor based on highly ordered poly(3-hexylthiophene) nanowires

Flexible organic field-effect transistors (FOFETs) based on organic semiconductor nanowires show great potential, due to their excellent mobility and uniform device performance. However, the current nanowire fabrication processes lack effective control over the organic semiconductor crystallization, which resulted in poor crystal orientation and nonuniform surface quality, causing notable variations in device performance. In this regard, a universal method known as nano-restricted coaxial focused electrohydrodynamic (NCFE) printing technology was developed, to fabricate high-performance and highly ordered nanowires. The method utilizes high-viscosity silicone oil as a sacrificial layer, which shears and refines the organic semiconductor ink under the action of an electric field, creating a nano-restriction effect that improving the printing resolution. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) revealed that the prepared P3HT nanowires possess exceptionally smooth surfaces with a roughness of only 0.3 nm. Furthermore, they exhibit an increased degree of structural order, as evidenced by UV-Vis absorption spectroscopy and grazing-incidence X-ray diffraction (GIXD). Using poly(3-hexylthiophene) (P3HT) as example material, wafer-scale, large-area of nanowires was prepared. It was found that the mobility of FOFETs based on P3HT nanowires is 6 times higher than that of conventional thin-film. This technology is expected to be applicable to the fabrication of nanowires from various materials, it provides a new manufacturing process for high-performance, highly integrated organic electronics.