| Abstract: | Optimized growth conditions of the epitaxial GaN layers on the (0001) oriented sapphire substrates in the Ga/HCl/NH3/H2 system have been proposed. The corresponding growth rate varied about the value 0.5 μm · min−1. The study of surface morphology and X-ray diffraction have confirmed the single crystalline character of the layers even though the surface shows a faceted structure. The c/a ratio calculated from our measured data of the lattice parameters was found 1.624 which is relatively close to the ideal close-packed wurtzite structure value. The cathodoluminescent spectra of the layers with a sufficient thickness were characterized by a peak at 3.35 eV having a halfwidth of about 0.2 eV. |
