Layer-by-layer growth and growth-mode transition of SrRuO 3 thin films on atomically flat single-terminated SrTiO 3 (1 1 1) surfaces

Abstract

We report on growth-mode transitions in the growth of SrRuO 3 thin films on atomically flat Ti 4+ single-terminated SrTiO 3 (1 1 1) substrates, investigated by reflection high-energy electron diffraction and atomic force microscopy. Over the first ~9 unit cells, the dominant growth mode changes from island to layer-by-layer for the growth rate of 0.074 unit cells/s and the growth temperature of 700 °C. Moreover, in the course of growing SrRuO 3 films, the governing growth mode of interest can be manipulated by changing the growth temperature and the growth rate, which change allows for the selection of the desired layer-by-layer mode. The present study thus paves the way for integrations of SrRuO 3 thin layers into (1 1 1)-orientated oxide heterostructures, and hence multi-functional devices, requiring control of the sharp atomic-level interfaces and the layer-by-layer growth mode.