Interface structure of large-period lattice-matched in GaAs/InP superlattices grown by metalorganic molecular beam epitaxy: a high-resolution X-ray diffraction study

Abstract The interfacial structure of InGaAs/InP superlattices grown on (100) InP by metalorganic molecular beam epitaxy has been studied by fully dynamical simulations of high-resolution X-ray diffraction curves of the (200) and (400) reflection. The superlattice under investigation is lattice-matched and has a long period of ∼ 630 A. This kind of structure creates a very symmetrical X-ray pattern enveloping a large number of closely spaced satellite intensities with pronounced maxima and minima. It appears in the dynamical analysis that the position and shape of these maxima and minima is extremely sensitive to the number of molecular layers N and atomic spacing d of the InGaAs and InP layer, as well as the presence of interfacial strained layers. Strain resulting from impurities in the InP barriers also played a major role in the analysis. Excellent fits were obtained for both reflections on the scale of one molecular layer.