Effect of ammoniating temperature on structural and morphologic properties of nanostructured GaN

Nanostructured GaN was synthesized by ammoniating Ga2O3/Mo films at different temperatures in a quartz tube. The as-synthesized GaN was studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) and Fourier transform infrared (FTIR) spectroscopy. The results show that the nanostructured material is single-crystal GaN with hexagonal wurtzite structure. The ammoniating temperature of the samples has an evident effect on the morphology and structure of the nanostructured GaN synthesized by this method. Lower temperature promotes the growth of wire-like structures and higher temperature facilitates the formation of the sheet-like structure. The growth mechanism of the nanostructured GaN was also discussed.