GaN/AlGaN multiple quantum wells grown on transparent and conductive (-201)-oriented β-Ga2O3 substrate for UV vertical light emitting devices

by Idris A Ajia, Y Yamashita, K Lorenz, MM Muhammed, L Spasevski, Dhaifallah Almalawi, J Xu, K Iizuka, Y Morishima, Dalaver H Anjum, Nini Wei, RW Martin, A Kuramata, Iman S Roqan
Year: 2018 DOI: https://doi.org/10.1063/1.5025178

Abstract

GaN/AlGaN multiple quantum wells (MQWs) are grown on a -oriented β-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 well-defined 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 β-Ga2O3 substrate. A detailed analysis of time-integrated and time-resolved photoluminescence measurements shows that the MQWs grown on a β-Ga2O3 substrate are of higher optical quality. Our work indicates that the -oriented β-Ga2O3 substrate can be a potential candidate for UV vertical emitting devices.

Keywords

GaN/AlGaN multiple quantum wells grown on transparent and conductive (-201)-oriented β-Ga2O3 substrate for UV vertical light emitting devices