Shape control of AlGaAs selective oxidation by intermixing method

Abstract

Shape control of AlGaAs selective oxidation regions by heterointerface intermixing was investigated. The oxidation rate dependence on the intermixing conditions was characterized. Under 880 °C with three hours of intermixing, the oxidation rate was reduced to half that of the usual oxidation without intermixing. The thicknesses of a GaAs capping layer and a deposited SiO2 layer affected the oxidation rate. A detailed analysis of the oxidation after intermixing was carried out by scanning transmission electron microscopy (STEM) measurement. On the basis of the oxidation characteristics with intermixing, in-plane shape control was demonstrated. This result will be helpful in the fabrication of complicated device shapes.