title: Direct Nanoscale Analysis of Temperature-Resolved Growth Behaviors of Ultrathin Perovskites on SrTiO3.
abstract: Revealing growth mechanism of a thin film and properties of its film-substrate interface necessarily require microscopic investigations on the initial growth stages in temperature- and thickness-resolved manners. Here we applied in situ scanning tunneling microscopy and atomic force microscopy to investigate the growth dynamics in homo- (SrTiO3) and hetero- (SrRuO3) epitaxies on SrTiO3(001). A comparison of temperature-dependent surface structures of SrRuO3 and SrTiO3 films suggests that the peculiar growth mode switching from a "layer-by-layer" to "step-flow" type in a SrRuO3 films arises from a reduction of surface migration barrier, caused by the change in the chemical configuration of the interface between the topmost and underlying layers. Island densities in perovskite epitaxies exhibited a clear linear inverse-temperature dependence. A prototypical study on island nucleation stage of SrTiO3 homoepitaxy revealed that classical diffusion model is valid for the perovskite growths.
authors.affiliation: Department of Physics, University of Seoul , Seoul 02504, Korea.
authors.forename: Young Jun
authors.initials: YJ
authors.lastname: Chang
authors.affiliation: Center for Correlated Electron Systems, Institute for Basic Science , Seoul 08826, Korea.|Department of Physics and Astronomy, Seoul National University , Seoul 08826, Korea.
authors.forename: Soo-Hyon
authors.initials: SH
authors.lastname: Phark
keywords: SrTiO3; growth mode; island nucleation; perovskite; scanning tunneling microscopy