Large-area oxidation of AlAs layers for dielectric stacks and thick buried oxides

The wet oxidation of AlAs and AlGaAs has been limited to relatively small lateral dimensions and relatively thin layers. Approaches are described to extend the oxide dimensions both horizontally and vertically, creating large-area and thick buried oxides. Two types of large-area structures are examined: dielectric stacks with thin buried oxides and semiconductor-on-insulator structures with thick buried oxides. Low Al-content AlGaAs layers with low oxidation rates are used as the high-index layers in large-area dielectric-stack structures. High Al-content AlGaAs layers with low volume contraction are used to create stable, thick buried oxides with millimeter-scale areas. [PUBLICATION ABSTRACT]