Surface characterization of homoepitaxial β- FeSi2 film on β- FeSi2 (111) substrate by X-ray photoelectron and absorption spectroscopy

Surface characterization of a homoepitaxial β- FeSi2 film grown on a β- FeSi2 single crystal synthesized with a temperaturegradient solution method was performed by X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). The annealing to remove native oxide layers on the crystal before homoepitaxial growth induced the formation of Fe-rich silicide in the surface. The XAS spectra confirm that the homoepitaxial β- FeSi2 film can be grown on the crystal, while Fe-rich silicide is partially formed. The control of the surface chemical state is important to obtain homoepitaxial films with excellent quality.