X-RAY-SCATTERING AND ABSORPTION STUDIES OF MNAS GAAS HETEROSTRUCTURES/

Ferromagnetic MnAs thin films grown on GaAs (001) substrates by molecu lar-beam epitaxy have been studied by the methods of grazing incidence x-ray scattering, x-ray diffraction, and extended x-ray-absorption fi ne structure. Microstructures in two films prepared with different fir st-layer growth conditions (template effects) are compared in terms of the interfacial roughness in the layer structure, lattice constants, epilayer thickness, local environment surrounding the Mn atoms, coordi nation number, and local disorder. Our results indicate that the templ ate effects can cause significant differences in the local structures and crystallinity of the MnAs epitaxial layers. (C) 1996 American Inst itute of Physics.