Optical and structural properties of GaN epitaxial layers on LiAlO sub(2) substrates and their correlation with basal-plane stacking faults

• Published in: Journal of crystal growth Vol. 434; pp. 62 - 66
• Main Authors: Lutsenko, E V, Rzheutski, M V, Pavlovskii, V N, Yablonskii, G P, Alanzi, M, Hamidalddin, A, Alyamani, A, Mauder, C, Kalisch, H, Reuters, B, Heuken, M, Vescan, A, Naresh-Kumar, G, Trager-Cowan, C
• Format: Journal Article
• Language: English
• Published: 15-01-2016
• Subjects: Computing time; Correlation; Density; Gallium nitrides; Optical properties; Position (location); Stacking faults; Substrates
• ISSN: 0022-0248
• DOI: 10.1016/j.jcrysgro.2015.10.036

The optical and structural properties of m-plane GaN layers grown by metal organic vapor phase epitaxy on LiAlO sub(2) (100) substrates were investigated. Temperature-dependent and time-resolved photoluminescence (PL), X-ray diffraction and Raman scattering measurements were performed to analyze the correlation of the sample properties with the density of I sub(1)-type basal-plane stacking faults (BSFs). Electron channeling contrast imaging was used to reveal and calculate the density of BSFs reaching the surface of an m-plane GaN/LiAlO sub(2) layer. It was shown that a local increase of BSF density in the investigated samples results in a rise of the total PL efficiency at low temperatures because of the localization of excitons at BSFs and, therefore, a suppression of their diffusion to nonradiative centers. Parameters of time decay and temperature quenching of the BSF-related PL band were determined. A correlation of both epsilon sub(xx) and epsilon sub(zz) strain components with the BSFs and crystal mosaicity was observed, and possible reasons of this correlation are discussed.