The surface of -phase (101) silicide which had been grown onto Si (111) contained surface states which were located at about 0.3eV below the Fermi level and which were related to Si adatoms. The latter, which had been seen as atomic-size protrusions in scanning tunnelling microscopic images, were arranged in various surface reconstructions. The average density of surface states was deduced from hydrogenation experiments. It was shown to be comparable to the density of adatoms on Si (111) 7 x 7. When the dangling bonds were saturated with H, the -FeSi2 surface was passivated against oxidation.
J.Chrost, J.J.Hinarejos, E.G.Michel, R.Miranda: Surface Science, 1995, 330, 34-40