Surface analysis of β-FeSi 2 layer epitaxially grown on Si(100)

Abstract

The epitaxial growth process of β-FeSi 2 on Si(100) surface under ultrahigh vacuum condition has been studied by low energy electron diffraction (LEED) and low energy ion scattering spectroscopy (LEIS). The LEED pattern of Si (100)-2×1 changes into amorphous structure with Fe deposition of about 10 Å at room temperature. With annealing at 540 °C, the LEED pattern shows 2×2 structure corresponding to the formation of the epitaxial β-FeSi 2 (100) template layer. The α-scan in Li +-LEIS and X-ray diffraction (XRD) study strongly suggest that the topmost surface of the 2×2 structure is terminated by Si atoms. By XRD, it is shown that the β-FeSi 2 develops with characteristic orientation even if iron reactant is deposited onto the template surface.