Abstract
The epitaxial aluminum nitride (AlN) crystals were grown on c-plane sapphire using high-temperature metal nitride vapor phase epitaxy at the source materials’ different molar flow ratios (V/III ratios). The effects of various V/III ratios on the surface morphology, crystalline quality, material straining, and optical properties of heteroepitaxial AlN thin films were studied using X-ray diffraction, scanning electron microscopy, Raman spectroscopy, and photoluminescence (PL). With the increase in the V/III ratio from 1473 to 7367, the substrate surface underwent changes that vary from whiskers to three-dimensional island structures, two-dimensional layered stack structures, and stacked sheet structures. Additionally, due to the presence of nanoscale pits on the substrate surface, almost all samples were tensile stressers. The PL spectra demonstrated the defect luminescence of the epitaxial films, indicating that nitrogen vacancies and oxygen impurities were the samples’ main defects.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
