Abstract
GaN/AlGaN multiple quantum wells (MQWs) are grown on a (2) over bar 01thorn-oriented beta-Ga2O3 substrate. The optical and structural characteristics of the MQW structure are compared with those of a similar structure grown on sapphire. Scanning transmission electron microscopy and atomic force microscopy images show that the MQW structure exhibits higher crystalline quality of welldefined quantum wells when compared to a similar structure grown on sapphire. X-ray diffraction rocking curve and photoluminescence excitation analyses confirm the lower density of dislocation defects in the sample grown on a beta-Ga2O3 substrate. A detailed analysis of time-integrated and time-resolved photoluminescence measurements shows that the MQWs grown on a beta-Ga2O3 substrate are of higher optical quality. Our work indicates that the (2) over bar 01thorn-oriented beta-Ga2O3 substrate can be a potential candidate for UV vertical emitting devices. Published by AIP Publishing.