HgTe-CdTe superlattices grown by low temperature MOCVD.

For the first time, the epitaxial growth of small-period HgTe- CdTe superlattices was achieved by metalorganic chemical vapor deposition. In the MOCVD process, a novel precracking technique was used that allowed the growth of superlattices at low temperatures from dimethylmercury, dimethylcadmium, and diethyltelluride. Layer thicknesses as small as 60angstroms were obtained. All the samples examined using transmission electron microscopy had sharp HgTe-CdTe interfaces. A 50 period HgTe-CdTe superlattice structure exhibited a sharp cut-off infrared transmission spectrum. In addition, compared to the band gap of Hg(1-x)Cd(x)Te alloy with the same composition, a narrowing of the superlattice band gap was observed as predicted by theoretical studies.