EFFECTS OF LOW-TEMPERATURE-GROWN GAAS LAYER ON COMPOSITIONAL DISORDERING OF ALGAAS GAAS SUPERLATTICES/

Effects of thickness and position of the low-temperature-grown GaAs (L T-GaAs) layer on the compositional disordering of AlGaAs/GaAs superlat tice have been studied. Samples with a top LT-GaAs layer or a bottom L T-GaAs layer have been studied with various annealing conditions. It w as found that the LT-GaAs layer grown on top of the superlattice is mo re effective in causing disordering than the LT-GaAs layer grown at th e bottom. The amount of disordering increases with the thickness of th e LT-GaAs layer. A selective disordering process has been developed us ing a patterned LT-GaAs cap layer. This disordering technique is very simple and can be easily applied to device fabrication.