HETEROINTERFACES OF CDTE/ALPHA-SN/INSB STRUCTURE GROWN BY MOLECULAR-BEAM EPITAXY

A CdTe/alpha-Sn heterostructure has been grown on an InSb(100) substrate by molecular beam epitaxy at temperatures of 150 and 220 alpha C. The alpha-Sn layers were grown up to thicknesses of 64 and 38 % Angstrom, respectively, assisted by the stabilizing effect, which prevents the alpha-Sn to beta-Sn transition which normally occurs at 13.2 degrees C. Here we report a transmission electron microscopy study which indicates the blocking of planar defects at the interface of alpha-Sn and InSb, suppressing their propagation to the CdTe overlayer. However, by Raman spectroscopy, the peaks of In,Te-related compounds can be seen for every thickness of grey tin layers. This indicates that the interdiffusion of In and Te could not be prevented by the grey tin layer. However, we cannot deny the possibility of suppression of interdiffusion, because it depends upon the quality of the grey tin layer.