Synthesis and properties of triangular-shaped GaN nanorods via growth mode control

Abstract

The synthesis of wurtzite gallium nitride (GaN) nanorods with triangular shape on c-Al 2O 3 substrates using a thermal chemical vapor deposition process was investigated. It was possible to control nanorod shape and growth mode of GaN nanorods by change of sample geometry in the chamber using a mixture of GaN powder and Ga metal with ammonia gas reaction. It was found that the GaN nanorods were grown via both vapor–liquid–solid and vapor–solid mode with change of sample placement in the chamber. The morphology of the GaN nanorods was observed by field-emission scanning electron microscopy in secondary electron and back-scattered electron mode. High-resolution transmission electron microscopy, and X-ray scattering measurements revealed the GaN nanorods to have a single-crystalline wurtzite structure.