[0001] Oriented Aluminum Nitride One-Dimensional Nanostructures: Synthesis, Structure Evolution, and Electrical Properties

This paper presents a systematic investigation on the controlled synthesis of wurtzite aluminum nitride (AlN) one-dimensional (1D) nanostructures in a chemical vapor deposition (CVD) system using Al and NH(3) as starting materials. By controlling reaction temperature and NH(3) flow, nanostructures with manifold morphologies including nanoneedles, branched nanoneedles, short nanorods, slim nanorods, and nanofences were synthesized with high yield and selectivity. The correlation between experiment parameters and product morphologies was interpreted by a surface diffusion based model. Moreover, electrical properties of a single nanoneedle were studied for the first time, in which typical semiconductor characteristics were observed. Silicon was speculated to incorporate into the AlN nanoneedle from silicon substrates during the synthesis, which served as an n-type donor and was responsible for the observed electrical behavior.