Fabrication of GaN epitaxial films on Al2O3/Si (001) substrates

Single crystal GaN films of hexagonal modification have been fabricated on Al2O3/Si （001） substrates via a low pressure metalorganic chemical deposition （LP-MOCVD） method. The full width at half-maximum of （0002） X-ray diffraction peak for the GaN film 1.1 μm thick was 72 arcmin, and the mosaic structure of the film was the main cause of broadening to the X-ray diffraction peak. At room temperature, the photoluminescence （PL） spectrum of GaN exhibited near band edge emission peaking at 365 nm.