Degradation in GaAs/AlGaAs double‐heterostructure light‐emitting diodes

Degradation of GaAs/AlGaAs double‐heterostructure light‐emitting diodes under accelerated aging tests has been investigated through cathodoluminescence measurements. We observed an increase in intensity of the band‐edge emission and a decrease in that of defect‐related deep level emision for the cladding layers. As for the active layer, a decrease was observed in the intensity of the band‐edge emission. These results suggest that defects migrate gradually from the cladding layer into the active layer.