Aligned Circular-Type Nanowire Transistors Grown on Multilayer Graphene Film

High-performance transistors using semiconducting nanowires are very promising devices for flexible or transparent electronic applications. However, nanowire-based transistors inevitably have placement and alignment issues, which make them troublesome for real-world applications and can be limiting factors in novel applications. Here we present a novel device structure that can be easily adapted for producing high-yield nanowire transistors. We fabricated fully transparent circular tin oxide (SnO 2 ) nanowire transistors employing multilayer graphene films (MGFs) as a seed electrode and aligned nanowires as a semiconductor channel. The nanowires were grown directly on MGFs without metal catalysts through a vapor–solid (VS) mechanism. On the basis of these properties, aligned SnO 2 nanowires were grown only on the exposed MGF using patterned MGF/SiO 2 structures. Regardless of the growth direction of the nanowires centered on the MGF, the as-grown nanowires can play the role of transistor channels because of the circular shape of the gate and the source-drain electrodes. Consequently, the yield rate of circular nanowire transistor structure was around two times as high as that of existing linear nanowire transistor structure.