Al Contamination in InGaAsN Quantum Wells Grown by Metalorganic Chemical Vapor Deposition and 1.3 µm InGaAsN Vertical Cavity Surface Emitting Lasers

We obtained high-quality InGaAsN quantum wells (QWs) by metalorganic chemical vapor deposition (MOCVD). Our InGaAsN QWs showed low threshold current densities and high-temperature characteristics (550 A/cm2, 150 K at 1275 nm for 3QWs) in broad-area lasers. High output power (2.8 mW at 1280 nm) was also obtained from the room-temperature continuous operation of InGaAsN 3QW vertical cavity surface emitting lasers. We revealed the first solid evidence that unexpected Al incorporation (Al contamination) occurred in InGaAsN QWs continuously grown on GaAs/AlGaAs structures by MOCVD. Our results suggest that Al contamination leads to a rough surface and low photoluminescence intensity of the InGaAsN QWs. By minimizing Al contamination, high-quality InGaAsN QWs were obtained. Al contamination in InGaAsN QWs should be carefully considered in the MOCVD growth of InGaAsN-based devices.