Laterial wet oxidation of AlAs laeyr in GaAs/AlAs heterostructures grwon by MBE on GaAs (n 1 1) A substrates

摘要

Laterial sidewall oxidaion of AlAs laeyrs grown on GaAs (1 0 0) and (n 1 1)A-oriented substrates (n=1, 2, 3, or 4) within a heterostructure was studied. The oxidation rate for each type of substrate was measured between 390 deg C and 450 deg C. The oxidation data concerning the time dependence of the oxidation rate was very well fitted by a theoretical formual based on a Si koxidation model. The time dependence of oxidation rate followed a linear law for the initial process an successively a parabolic law. The oxidation rate is highly anisotroic which is related to the symmetry of the crystal structure. An oxidation model was proposed from the results of anisotropic activtion energy of oxidation.