X-RAY-SCATTERING AND TOPOGRAPHY STUDIES OF HG1-XMNXTE EPITAXIAL-FILMS

Epitaxial films of Hg1-xMnxTe (MMT), between 2 and 10 mum thick, have been grown by MOVPE on GaAs and CdZnTe substrates and their perfection assessed by high-resolution x-ray scattering and topography. The full width al half height maximum (FWHM) Was found to vary inversely with the MMT layer thickness, independently of Mn concentration or substrat e type. A general increase in integrated intensity with thickness was observed, though with substantial variations between individual data p oints. Double-axis topography and triple-axis scattering showed that t he greatest contribution to the double-axis FWHM came from tilts betwe en subgrains within which the strain was small. Little difference was seen either in the double-axis FWHM or triple-axis isointensity contou rs between thick MMT layers grown on GaAs or CdZnTe substrates. The mo del of Ayers et al does not appear to be applicable to the system, whi ch incorporates a CdTe buffer layer on the GaAs.