Faceted and vertically aligned GaN nanorod arrays fabricated without catalysts or lithography.

Monocrystalline, vertically aligned and faceted GaN nanorods with controlled diameter have been synthesized by selective organometallic vapor phase epitaxy (OMVPE) onto GaN exposed at the bottom of pores in silicon dioxide templates patterned by reactive ion etching through self-organized porous anodic alumina films. This process is free of foreign catalysts, and the nanorod diameter control is achieved without the need for low-throughput nanolithographic techniques. The use of conventional OMVPE growth conditions allows for the straightforward adaptation of conventional doping and heterostructure growth as will be necessary for the fabrication of nanorod-based strain-relaxed electrically pumped lasers and light-emitting diodes.