title: Generation of clean iron nanocrystals on an ultra-thin SiO(x) film on Si(001).
abstract: Upon exposure to Fe(CO)(5), the formation of pure cubic Fe nanocrystals with dimensions up to ~75 nm is reported on ultra-thin SiO(x) films (thickness ≈ 0.5 nm) on Si(001), which have been prepared in situ under UHV conditions. The active centers for initial decomposition of Fe(CO)(5) resulting in the growth of the Fe clusters are proposed to be SiO sites. After nucleation at these sites, further crystal growth is observed due to autocatalytic dissociation of Fe(CO)(5) at room temperature. The density of the Fe clusters can be increased by irradiating the surface with a focused electron beam (15 keV) prior to gas exposure. The formation of the active SiO sites upon electron irradiation is attributed to oxygen desorption via the Knotek-Feibelman mechanism.
authors: Lehrstuhl für Physikalische Chemie II and Interdisciplinary Center for Molecular Materials, Universität Erlangen-Nürnberg, Egerlandstraße 3, D-91058 Erlangen, Germany.
authors: Marie-Madeleine
authors: MM
authors: Walz
authors: Florian
authors: F
authors: Vollnhals
authors: Michael
authors: M
authors: Schirmer
authors: Hans-Peter
authors: HP
authors: Steinrück
authors: Hubertus
authors: H
authors: Marbach