The crystallographic quality and band-edge transition of as-deposited PALE AlN films via metal organic chemical vapor deposition

Abstract

Diversification of pulse cycle numbers proportional to the AlN films thickness using PALE technique on c-plane sapphire substrate were carried out via MOCVD. It was experiential that the structural features of as-deposited AlN films were significantly impinged on the film thickness where the highest number of pulse cycles (1050 pairs) present the lowest (0 0 0 2)-symmetry and (1 0–1 2)-asymmetry XRC analysis, manifest a decrease of threaded dislocation density. The XPS spectra present a low foreign impurities inclusion on the AlN film surface was achieved even at highest cycle number by engaging the PALE growth technique. The spectroscopy of PL and UV–Vis NIR were employed to probe the optical characteristics involving the absorption and their band-edge transitions. In both optical spectroscopies, the room temperature of band-edge emission lines has expressed a significant interconnection between the structural and optical quality of as-deposited AlN films at different pulse cycle numbers.