Growth of high-quality Al xGa 1−xAs ( x = 0.05−0.65) by low-pressure metalorganic vapour phase epitaxy using dimethylethylamine-alane

Abstract

High-quality Al x Ga 1− x As ( x = 0.05−0.65) has been grown by low-pressure metalorganic vapour phase epitaxy (MOVPE) using dimethylethylamine-alane (DMEAA1) as aluminum precursor. No temperature dependence is found for the growth rate or for the aluminum incorporation between T = 575° C and T = 725° C. The aluminum incorporation is linearly dependent on the fraction of DMEAA1 in the gas phase. Photoluminescence (PL) measurements show a very low carbon incorporation, which is independent of the aluminum fraction and the growth temperature. Because of this low carbon content, the spilayers show n-type conductivity up to aluminum fractions of 0.65 and high carrier mobilities. Excitonic PL peaks show narrow linewidths that are comparable with the best values reported in the literature. This indicates that the impurity content is low and that compositional uniformity throughout the layer is very good. A multi quantum well with good PL properties has also been grown.