Growth of group III nitride nanostructures on nano-imprinted sapphire substrates

Nanostructures of group III nitrides have been fabricated on nano-imprinted sapphire substrates by nitrogen radical assisted pulsed laser deposition. We have found that the group III nitride nanostructures produced by this method incline toward the incident direction of the nitrogen radical source, probably due to the shadowing effect. The inclinations of the nanostructures are the result of an oblique reactive gas flux and re-evaporation of metal that is shadowed from the gas flux and not nitrided. We have demonstrated that it is possible to control the shape of nanostructure, three dimensionally, by utilizing this inclination phenomenon, which should be quite useful for the fabrication of photonic crystals.