Comparison of epitaxial thin layer GaN and InP passivations on InGaAs/GaAs near-surface quantum wells

The optical properties of the in situepitaxialGaN and InP passivated InGaAs∕GaAs near-surface quantum wells, which were fabricated by metal organic vapor phase epitaxy, are investigated. Low-temperature photoluminescence(PL), time-resolved photoluminescence, and photoreflectance are used to study the passivation effect. Both GaN and InPpassivations are observed to significantly enhance the PL intensity and carrier lifetime and to reduce the surface electrical fields. Comparison of the methods shows that the epitaxialInPpassivation is more effective. However, epitaxialGaN and nitridation methods are comparable with InPpassivation.Peer reviewe