Stress measurements in oxidized GaAs-AlAs structures by micro-Raman spectroscopy

We investigated the stress distribution induced in a GaAs layer by the lateral oxidation of an underlying AlAs layer with micro-Raman spectroscopy. Combining with the measurement of micro-photoluminescence (PL), we found smaller strain, better homogeneity and lower density of the nonradiative recombination center for oxidized GaAs-AlAs heterostructures containing a thin AlGaAs middle layer compared to that without the AlGaAs layer.