MESOSCOPIC Pb WIRES ON ORDERED VICINAL Si(111)

摘要

Growth of Pb mesoscopic wires on ordered vicinal Si(111) surface covered with sub-monolayer amount of Au has been studied by RHEED and LEEM. For a sample misoriented by 14.42° from the (111) plane towards [2 1 1] azimuthal direction at a coverage equal to 0.28 ML of Au, the RHEED pattern showed a regular distribution of monoatomic steps. At room temperatures and 280 K spontaneous self-organization of mesoscopic Pb wires on these substrates was observed. Three-dimensional elongated islands were first observed after deposition of one Pb monolayer. With further Pb deposition these elongated islands grew into set of perfectly parallel wedge-shaped wires. The wires were approximately 90 nm wide, up to several μm long and were aligned Parallel to substrate steps. The density of wires was strongly correlated with perfection of Si(533) surfaces. A model of the wire is presented.