Suppression of <100> Dark-Line Defect Growth in AlGaAs/InGaAs Single Quantum Well Lasers Grown on Si Substrates

We report the suppression of <100> dark-line defect growth in AlGaAs/In x Ga 1- x As quantum well lasers on Si substrates grown by metalorganic chemical vapor deposition. An AlGaAs/In 0.02 Ga 0.98 As laser on Si with an In 0.08 Ga 0.92 As intermediate layer (InGaAs IL) has a stress-relieved active layer, while an AlGaAs/In 0.07 Ga 0.93 As laser on Si with an InGaAs IL has a compressive-stress induced active layer. The AlGaAs/In 0.07 Ga 0.93 As laser had a higher threshold current density than the AlGaAs/In 0.02 Ga 0.98 As laser due to the increased bending of the threading dislocations in the active layer. The lifetimes of these lasers at 300 K were markedly increased, due to the reduction in the dark spot density resulting from the introduction of the InGaAs IL and the reduction in the <100> dark-line defect growth velocity resulting from the dislocation pinning in the InGaAs active layer.