Structure and electrical property of gallium nitride nanowires synthesized in plasma-enhanced hot filament chemical vapor deposition system

Aligned gallium nitride (GaN) nanowires were catalytically synthesized in a plasma-enhanced hot filament chemical vapor deposition system, in which GaN powder and nitrogen were used for the gallium and nitrogen sources, respectively. The results of scanning electron microscope, X-ray diffractometer, micro-Raman spectroscopy and transmission electron microscope indicate that the n-type GaN nanowires with different diameters are formed in wurtzite crystal structure. Combined the vapor-liquid-solid growth mechanism with the plasma-related effects, the formation of n-type GaN nanowires with different diameters was analyzed. The electrical property of a single GaN nanowire was measured in transmission electron microscope at room temperature and the result indicates that the current-voltage curve exhibits a nonlinear behavior and a double diode-like characteristic. In particular, the double diode-like characteristic is highly related to the application of GaN nanowires in the area of nano-diode devices such as alternating current limiter.