Metalorganic chemical vapor deposition of GaInNAs lattice matched to GaAs for long-wavelength laser diodes

Abstract

The crystal growth of GaInNAs lattice matched to GaAs by metalorganic chemical vapor deposition using dimethylhydrazine as the nitrogen source is described for realizing long-wavelength laser diodes. It was found that the crystalline quality of GaInNAs on AlGaAs is improved by inserting a GaAs spacer layer between GaInNAs and AlGaAs. The photoluminescence spectra of GaAs/Ga 0.9In 0.1N y As 1− y /GaAs-DH was measured at room temperature with N content y of 1.5, 2.3 and 2.9%, respectively. The PL intensity decreases with increasing N content, though the lattice mismatch of GaInNAs layers to GaAs substrates decreases with increasing N content. We also produced the laser diodes with GaInNAs active layer and measured the N content dependence of the threshold current density. With increasing N content, the threshold current density increases with the reduction of PL intensity. We made it clear that GaInNAs material system is applicable to a 1.3 μm laser diode on a GaAs substrate. We expect to achieve a good lasing performance at 1.3 μm with the most suitable growth condition and design of laser diodes.