X-ray characterization of single-crystal Fe films on GaAs grown by molecular beam epitaxy

Abstract

X-ray structural studies of Fe films grown on (100)GaAs by MBE have shown very well-oriented mosaic structure originating at the interface and presumably caused by the lattice mismatch of 1.34%. The size and structure of the domains depend upon growth conditions, but at film thicknesses approaching 1 μm, the films assume the character of bulk α-phase Fe. This study has shown that although RHEED photographs indicated smooth flat MBE growth of these films, they were inadequate to explain the anomolous transport and magnetic properties. On the other hand, careful x-ray studies, especially linewidth rocking-curve measurements, have revealed a very fine grain mosaic structure which can strongly affect those properties.