Electrical transport properties of size-tuned ZnO nanorods

Size-tuned ZnO nanorod arrays (NRAs), aligned well vertically and laterally, were synthesized by catalyst-free, metalorganic chemical vapor deposition on GaN-buffered Al₂O₃ (0001) substrates by adjusting the O/Zn precursor ratio in the reactor. Their electrical transport properties were investigated using field effect transistors based on individual ZnO nanorods. We find that the carrier concentrations and mobilities in the nanorods are not very sensitive to the change of the precursor ratio. This suggests that altering the precursor ratio is a way of fabricating size-tuned ZnO NRAs with quite consistent electrical properties.