Improved PL intensity of InGaAs/GaAs SQW with a selectively oxidized AlAs layer

Data is presented on room temperature photoluminescence (PL) intensity measurements of InGaAs/GaAs single quantum wells (SQW's) adjoining a selectively oxidized AlAs layer. A drastic PL intensity reduction was observed for a sample with a direct interface between the GaAs barrier and the oxidized AlAs layer. Samples in which an AlGaAs layer was inserted between the SQW and the AlAs showed no such PL intensity reduction after oxidation provided the thickness of the AlGaAs layer was greater than 20 nm. The results provide important information for the design of oxide based optoelectronic devices operated at room temperature.