Dependence of lateral oxidation rate on thickness of AlAs layer of interest as a current aperture in vertical-cavity surface-emitting laser structures

The dependence of the wet oxidation process on the AlAs layer thickness used in selectively oxidized vertical-cavity surface-emitting-laser structures is studied in detail. A theoretical model based on a diffusion-reaction process is proposed. A rapid reduction in the oxidation rate is predicted with a reduction in the layer thickness of the ultrathin AlAs layer. The theoretical predictions are verified through experiments.