Influence of indium composition on the surface morphology of self-organized InxGa1−xAs quantum dots on GaAs substrates

Abstract

In x Ga 1−x As self-organized quantum dots with x=1.0, 0.5, and 0.35 have been grown by molecular beam epitaxy. The areal density, distribution, and shapes have been found to be dependent on x. The dot shape changes from a round shape for x=1.0 to an elliptical shape for x⩽0.5. The major axis and minor axis of the elliptical InxGa1−xAs dots are along the [1̄10] and [110] directions, respectively. The ordering phenomenon is also discussed. It is suggested that the dot–dot interaction may play important roles in the self-organization process.