Comparison of 10 MeV electron beam radiation effect on InGaN/GaN and GaN/AlGaN multiple quantum wells

Radiation effects of 10 MeV electrons on blue-lighting InGaN/GaN multiple quantum wells (MQWs) and ultraviolet-lighting GaN/AlGaN MQWs were investigated and compared by means of temperature-dependent and time-resolved photoluminescence (PL) methods. It was found that GaN/AlGaN MQWs showed better radiation tolerance than InGaN/GaN MQWs. In detail, the internal quantum efficiency of InGaN/GaN MQWs decreased sharply with increasing electron irradiation fluence whereas that of GaN/AlGaN MQWs remained nearly constant. The degradation of the emission properties of InGaN/GaN MQWs after irradiation was attributed to the generation of non-radiation recombination centers (NRCs) in MQWs. On the other hand, the radiation hardness of GaN/AlGaN MQWs was proved to be related to two factors: the irradiation-induced reduction of both exciton localization energy and NRC density. The results reported here are significant for the evaluation and design of GaN-based optoelectronic and electronic devices used in radiation environments.