Cathodoluminescence degradation signatures of AlGaAs‐based high‐power laser arrays

Low‐temperature spectrally resolved cathodo luminescence was implemented on degraded AlGaAs‐based high‐power laser bars to investigate the degradation signatures. We focused on laser bars at different degradation levels and two degradation patterns were described and attributed to two degradation mechanisms. The first one may be due to some locally poorer material quality and induces the formation of dark spots defects in injection channels, the other one (which is correlated to some damages created on the facet during the mounting of the bar) triggers the formation of some characteristic dark defects originating from the facet and extending within the (110) oriented current injection channels. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)