Estimation of the degradation of InGaN/AlGaN blue light-emitting diodes

The long-term accelerated degradation of GaN blue light-emitting diodes under current stress was investigated. From the degradation pattern of optical output with respect to time, the dependence of the degradation on current stress and an equation for estimation of the half-life of the diode were obtained. The major factor causing the degradation is the decrease in the radiative recombination probability due to defect level generation.