WET CHEMICAL-SEPARATION OF LOW-TEMPERATURE GAAS-LAYERS FROM THEIR GAAS SUBSTRATES

We reported a method of the wet chemical separation for low-temperatur e (LT) GaAs epitaxial layers grown by molecular beam epitaxy from thei r substrates. Samples with AlAs as well as AlGaAs etch-stop interlayer s were used in this study, but better properties have been found for t he samples with AlAs. Very interesting dependence of etching rate of t he citric acid based etchant on the sample growth temperature is repor ted. For illustration of usefulness of this method, the temperature de pendencies of the resistivity and Hall mobility measured on four separ ated LT-GaAs layers are presented.