GaSb-based laser diodes grown on MOCVD GaAs-on-Si templates

We report GaSb-based laser diodes (LDs) grown on on-axis (001) Si substrates and emitting at 2.3 µm. Two series of LDs were studied compared. For the first series, a GaAs-based buffer layer was by metal organic chemical vapor deposition (MOCVD) before growing heterostructure molecular-beam epitaxy (MBE). second MOCVD GaSb added between GaAs MBE heterostructure. Both exhibited threshold currents in 50–100 mA range several mW output power room temperature. They demonstrated continuous wave operation (CW) up to 70°C (set-up limited) without thermal rollover. Broad area record threshold-current densities 250–350 A.cm ?2 for LDs, spite cracks that appeared during device processing. These results show design fabrication steps buffer-layer stacks are critical issues epitaxial integration optoelectronic devices offer much performance improvement.