The fabrication technique and electrical properties of a free-standing GaN nanowire

We fabricated a free-standing structure of a GaN nanowire by selectively etching Si3N4, previously grown on a SiO2 substrate, for application to three-dimensional integrated circuits such as nanorelays and actuators. In the nanowire-deposition process we adopted electrophoresis and reactive ion etching techniques to achieve a well-aligned and free-standing nanowire. The electrical transport measurements were performed from room temperature down to liquid-nitrogen temperature. The current–voltage (I–V) characteristics showed a rectifying behavior in the whole temperature range. We analyze this property as a Schottky barrier formation between the nanowire and electrodes.