MetallicCaSi2epitaxial films on Si(111)

The growth of high-quality epitaxial ${\mathrm{CaSi}}_2$ films on Si(111) is described along with a determination of the silicide atomic structure and the structure of the ${\mathrm{CaSi}}_2$/Si interface. These films constitute the first example of an epitaxial non-transition-metal silicide. The lack of d electrons and the large difference in electronegativity between Ca and Si promise to endow epitaxial calcium silicide and the silicide-silicon interface with intriguingly different electronic properties from the thoroughly studied transition-metal silicides.