Formation of dysprosium silicide nanowires on Si(557) with two-dimensional electronic structure

The self-organized growth of dysprosium silicide nanowires on Si(557) has been studied using scanning tunneling microcopy and angle-resolved photoelectron spectroscopy. The nanowires grow on the (111) facets of the Si(557) surface with lengths exceeding 1000 nm and widths of 3–5 nm. Their metallic electronic structure shows a two-dimensional behavior with a strong dispersion, which is both parallel and perpendicular to the nanowires. For Dy coverages of around 2 A, it is demonstrated that the nanowires consist of hexagonal DySi2 monolayers, while at higher coverages they are predominantly formed from Dy3Si5 multilayers.