Facet-coated graded-index separate-confinement-heterostructure single-quantum-well lasers having low degradation rates (<1 percent/kh) at 70°C

The results of accelerated life testing of single-quantum-well (QW) lasers having graded-index (GRIN) separate-confinement heterostructure (SCH) active regions are reported. These results are the first to show that lasers grown by MOCVD can have low degradation rates (<1 percent/kh) at 70°C and are also the first light-emitting lifetime data for GRIN-SCH quantum-well lasers. The laser structures were grown by metalorganic chemical vapor deposition (MOCVD) at atmospheric pressure using an uninterrupted growth sequence. Shallow proton-bombarded 5-µm × 250-µm stripe-geometry lasers were fabricated from these wafers and lasers with and without Al2O3facet coatings were life tested at 70°C and 5 mW per mirrors facet. Facet-coated lasers have lived longer than 1100 h with degradation rates as low as 0.5 percent/kh.