Failure analysis of InGaAs/GaAs strained-Layer quantum-well lasers using a digital OBIC monitor

The mechanisms that cause the sudden failure of InGaAs/GaAs strained-layer quantum-well lasers (LD) are analyzed by monitoring an optical beam-induced current (OBIC). Statistically, the LDs that suddenly fail have different n-OBIC/sub ridge/ intensity profiles (p-n junction OBIC under the ridge normalized by that under the electrode) from LDs with conventional catastrophic optical damage. It appears that dislocations are generated in the vicinity of an antireflection (AR) facet and extend to the AR facet, and meltdown finally occurs there. The suppression of dislocation generation around the AR facet is important in regards to preventing sudden failure.