STRUCTURAL AND OPTICAL CHARACTERIZATION OF NON-POLAR A-PLANE GAN THIN FILMS GROWN ON R-PLANE SAPPHIRE VIA HIGH-TEMPERATURE ALN NUCLEATION LAYERS BY METALORGANIC CHEMICAL VAPOR DEPOSITION

摘要

Non-polar A-plane GaN layers were grown on R-plane sapphire substrates using high temperature A1N nucleation layers. X-ray characterization shows improved crystalline quality for A-GaN grown by this method compared to utilizing traditional low-temperature GaN nucleation layers. Photoluminescence (PL) measurements indicate the potential of A-GaN materials for achieving high optoelectronic device quality. Standard InGaN/GaN MQW structures were grown on the above non-polar A-plane GaN bulk layers, with preliminary results showing a much lower indium concentration in the well than for C-GaN templates grown in the same run.