OPTICAL AND ELECTRICAL CHARACTERIZATION OF BETA-FESI2 EPITAXIAL THIN-FILMS ON SILICON SUBSTRATES

Electrical measurements have ben carried out on epitaxial FeSi2 layers on silicon substrates, the silicide thickness being either 180 or 350 angstrom. A direct gap of 0.85 eV was measured by optical absorption. Current-voltage characteristics of mesa-structures Cr/Fe/FeSi2/Si show a p-type semiconductor behavior. Capacitance-voltage and capacitance-temperature data at different frequencies indicate a large response of deep levels of interface states. Admittance spectroscopy yields the activation energy and capture cross of two levels. Finally an energy-band diagram is proposed.