Observation of nonbiased degradation recovery in GaInAsP/InP laser diodes

Conventional accelerated lifetests of laser diodes generally involve operating the devices continuously at either constant drive current or power output with periodic recording of their characteristics. In this work, a new observation of degradation recovery from a noncontinuous lifetest performed on 1.3- mu m GaInAsP/InP double-heterostructure (DH) laser diodes of the inverted-rib structure is reported. This nonconventional lifetest method involves constant 5-mW/facet biasing at 50 degrees C followed by a period of no bias at room temperature. On average, the threshold current and current for 5-mW/facet output reduced by 6.7 and 8.4%, respectively, during the unbiased period. Redistribution of mobile defects in the cladding layer is postulated to be the mechanism responsible for the degradation recovery.<
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