High Brightness Ingan Leds Degradation at High Injection Current Bias

Abstract

In this work, we report on the results of a reliability evaluation, in terms of electrical characteristics, stability and optical output power maintenance carried out on high brightness GaN/InGaN blue LEDs. Constant and pulsed bias where investigated over devices with and without heat sink in order to identify the influence of self-heating on the devices reliability. Several degradation modes have been identified such as increase of reverse and generation/recombination current, increase of the series resistance and decrease in the optical emitted power