The annealing of double-heterostructure GaInAsP-InP 1.3 μm laser diodes

Subsequent to fabrication, double-heterostructure laser diodes with planar GaInAsP active regions are subjected to an annealing or burn-in process during which they are operated at a constant 5 mW light-output power at a temperature of 50 degrees C. In general, small increases of drive current are found in the first 1000 to 2000 h of operation after which the lasers settle down. In the present diodes, drive current increases of typically 6% occurred. There is little change in threshold current and the changes seen are mainly due to a decrease in slope efficiency. In all cases the changes decrease gradually after about 2000 h and revert to the behavior expected of long lived and reliable quaternary lasers. A model for the annealing of double-heterostructure laser diodes has been successfully extended to describe these effects