High-resolution cathodoluminescence investigation of degradation processes in ingan green laser diodes

III-nitride materials have revolutionized optoelectronics as they are behind UV-blue LEDs and laser diodes. In most III-nitride optoelectronic devices, light emission arises from InGaN multi quantum wells (MQW) layers. Increasing the In fraction in InGaN MQWs allows reaching green emission (500- 550 nm) and thus closing the ‘green gap’, with potential applications in biomedical science and miniaturized high brightness beamers. However, increased incorporation of In leads to limited reliability of green LEDs and lasers even under moderate operating conditions. Here we aim at investigating the physical processes responsible for the degradation of commercial InGaN based green laser diodes. The laser diodes under study have been stressed under a controlled way and their threshold current has been systematically monitored at different stages of the stress process. Such measurements give a first insight into the degradation process at work in the green laser diodes. However, they do not give much information about the microscopic processes involved here.