In this study we have investigated the change of structural properties for GaN powders annealed in an NH3 atmosphere at temperatures of 850, 950, 1050 and 1150 °C for 2 hours, by using Scanning Electron Microscopy(SEM), X-ray diffraction(XRD), neutron diffraction(ND), and Raman scattering. GaN powders annealed in a N2 atmosphere at 1050 °C for 2 hours was prepared to compare the results with those annealed in an NH3 atmosphere. SEM images shows that the GaN powders are of the form of aggregates composed of nano-GaN particles. All XRD, ND and Raman scattering peaks from the samples annealed in an NH3 atmosphere become stronger and narrower as annealing temperature increases. The nitrogen-deficient phases such as Ga2O3 and Ga2H were observed in the sample annealed at 1050 °C in a N2 atmosphere, but such nitrogen-deficient phases was absent in the GaN powders annealed in an NH3 atmosphere. It is suggested in this study that the optimal annealing condition of GaN powders for the preparation of the growth of GaN substates is the annealing at temperatures higher than 1150 °C in a NH3 atmosphere.
|Journal||Journal of the Korean Physical Society|
|Issue number||SUPPL. Part 1|
|Publication status||Published - 2001 Dec 1|
ASJC Scopus subject areas
- Physics and Astronomy(all)