Al xO y induced intermixing in GaAs/AlGaAs quantum wells

Abstract

Impurity-free interdiffusion (IFID) is commonly used for fabrication of active devices due to the low defect density and degradation of the material after processing. This is achieved by using laterally oxidized AlAs layers that are mostly used for current confinement apertures in VCSELs and edge emitters. The effect of Al xO y-induced IFID is presented using two samples of 4 quantum wells grown by MOCVD where the barrier material is Al 0.54Ga 0.46As and the well material is GaAs. Photoluminescence emissions reveal that the stability of the oxide layers during oxidation and annealing is found to be strongly dependent on the oxide thickness. The presence of Al metal in contact with the oxide is found to dramatically enhance IFID. Show more