Search

Abstract: Rapid thermal annealing (RTA) has been demonstrated as an effective way to improve the crystal quality of GaInNAs(Sb) quantum wells (QWs). However, few investigations have been made into its application in laser growth and fabrication. We have fabricated 1.3μm GaInNAs lasers, both as -grown and with post-growth RTA. Enhanced photoluminescence (PL) intensity and decreased threshold current are obtained with RTA, but the characteristic temperature T 0 and slope efficiency deteriorate. Furthermore, T 0 has an abnormal dependence on the cavity length. We attribute these problems to the deterioration of the wafer''s surface. RTA with deposition of SiO2 was performed to avoid this deterioration, T 0 was improved over the samples that underwent RTA without SiO2. Post-growth and in situ annealing were also investigated in a 1.55μm GaInNAsSb system. Finally, continuous operation at room temperature of a GaAs-based dilute nitride laser with a wavelength over 1.55μm was realized by introducing an in situ annealing process. [Copyright &y& Elsevier]

Abstract: Molecular beam epitaxy (MBE) growth of (InyGa1− y As/GaAs1− x Sb x )/GaAs bilayer quantum well (BQW) structures has been investigated. It is evidenced by photoluminescence (PL) that a strong blue shift of the PL peak energy of 47meV with increasing PL excitation power from 0.63 to 20mW was observed, indicating type II band alignment of the BQW. The emission wavelength at room temperature from (InyGa1− y As/GaAs1− x Sb x )/GaAs BQW is longer (above 1.2μm) than that from InGaAs/GaAs and GaAsSb/GaAs SQW structures (1.1μm range), while the emission efficiency from the BQW structures is comparable to that of the SQW. Through optimizing growth conditions, we have obtained room temperature 1.31μm wavelength emission from the (InyGa1− y As/GaAs1− x Sb x )/GaAs BQW. Our results have proved experimentally that the GaAs-based bilayer (InyGa1− y As/GaAs1− x Sb x )/GaAs quantum well is a useful structure for the fabrication of near-infrared wavelength optoelectronic devices. [Copyright &y& Elsevier]