Sn diffusion effects on x-ray diffraction patterns of Pb1−<i>x</i>Sn<i>x</i>Te–PbSe<i>y</i>Te1−<i>y</i> superlattices

Abstract

Three kinds of superlattices consisting of good lattice-matched and -mismatched materials (Pb0.76Sn0.24Te-PbSe0.10Te0.90, Pb0.76Sn0.24Te-PbTe, and Pb0.76Sn0.24Te-PbSe0.18Te0.82 superlattices) were prepared by a hot-wall epitaxy and their high-angle x-ray diffractions were measured. Sn-diffusion effects on the satellite structure are studied and it was found that Sn diffusion increases lattice distortion for lattice-matched Pb0.76Sn0.24Te-PbSe0.10Te0.90 superlattice and for lattice-mismatched Pb0.76Sn0.24Te-PbSe0.18Te0.82 superlattice, on the other hand, decreases it for Pb0.76Sn0.24Te-PbTe superlattice. And it was also found that very large diffusion of Sn occurs during growth even when the substrate temperature is 250 °C.