STRUCTURAL CHARACTERIZATION OF HG0.78CD0.22TE/CDTE LPE HETEROSTRUCTURES GROWN FROM TE SOLUTIONS

Hg0.78Cd0.22Te epilayers have been grown on CdTe substrates by slider liquid phase epitaxy. The crystal quality of the epitaxial material has been studied in as-grown structures and chemically or mechano-chemically prepared bevels using X-ray topography, double crystal diffractometry and transmission electron microscopy. It has been found that the bulk epilayers exhibit a very high crystal quality, as evidenced by the relatively low density of dislocations and the very narrow Bragg peaks. In contrast, a high dislocation and precipitate density and a broadening of the Bragg peak have been detected in the epilayer near the interface. Finally, a Hg decrease in the layer and a corresponding Hg increase in the substrate close to the interface have been observed.