Recoverable degradation of blue InGaN-based light emitting diodes submitted to 3MeV proton irradiation

This paper reports on the degradation and recovery of two different series of commercially available InGaN-based blue light emitting diodes submitted to proton irradiation at 3MeV and various fluences (10(11), 10(13), and 10(14)p(+)/cm(2)). After irradiation, we detected (i) an increase in the series resistance, in the sub-turn-on current and in the ideality factor, (ii) a spatially uniform drop of the output optical power, proportional to fluence, and (iii) a reduction of the capacitance of the devices. These results suggest that irradiation induced the generation of non-radiative recombination centers near the active region. This hypothesis is further confirmed by the results of the recovery tests carried out at low temperature (150 degrees C). (c) 2014 AIP Publishing LLC.