Quantitative Bestimmung der Zusammensetzung von Ga1−xAlxAs-Epitaxieschichten mit der Elektronenstrahl-Mikroanalyse (ESMA)

Several methods of correcting the X-ray intensity in the electron probe microanalysis were examined for getting the local concentrations of Ga, Al and As in Ga_1−xAl_xAs epitaxial layers. Most correct results were obtained by combining the method of BIRKS for the Al-determination with that of DUNCUMB /REED /SPRINGER for the Ga-determination. In this case the mean departure from 50% for the sum of the Ga and Al atom-percents is only −0.1%. Equations for the mutual conversion of concentrations into masses, necessary for the practical use, are given in an appendix.