GROWTH IN ULTRAHIGH-VACUUM AND STRUCTURAL CHARACTERIZATION OF FESI2 ON SI(111)

FeSi2 films grown in ultrahigh vacuum on Si (111) substrates by solid phase epitaxy (SPE) have been characterized by several in situ and ex situ structural techniques: reflection high-energy electron diffraction (RHEED), x-ray diffraction (XRD), and Rutherford backscattering (RBS). The results on a film a few hundred angstroms thick confirm that the FeSi2 which forms in these conditions is the semiconducting-beta-phase and that an epitaxial growth takes place with the (202) and/or (220) FeSi2 planes parallel to the Si (111) planes. The lattice mismatch measurements in films as thin as 100 angstrom indicate that the films are little or no elastically strained, at least at a FeSi2 growth temperature of 600-degrees-C.