I. S. Roqan, M. M. Muhammed ''−201 [beta]- Gallium oxide substrate for high quality GaN materials'', 2015, Proc. SPIE 9364, Oxide-based Materials and Devices VI, 93641K ;
−201 oriented β-Ga2O3 has the potential to be used as a transparent and conductive substrate for GaN-growth. The key advantages of Ga2O3 are its small lattice mismatches 4.7, appropriate structural, thermal and electrical properties and a competitive price compared to other substrates. Optical characterization show that GaN layers grown on −201 oriented β-Ga2O3 are dominated by intense bandedge emission with a high luminescence efficiency. Atomic force microscopy studies show a modest threading dislocation density of ~108 cm-2, while complementary Raman spectroscopy indicates that the GaN epilayer is of high quality with slight compressive strain. Room temperature time-findings suggest that the limitation of the photoluminescence lifetime 500ps is due to nonradiative recombination arising from threading dislocation. Therefore, by optimizing the growth conditions, high quality material with significant optical efficiency can be obtained.
DOI: 10.1117/12.2076475