Direct Nanoscale Analysis of Temperature-Resolved Growth Behaviors of Ultrathin Perovskites on SrTiO3
详细信息 查看全文
- 作者：Young Jun Chang ; Soo-hyon Phark
- 刊名：ACS Nano
- 出版年：2016
- 出版时间：May 24, 2016
- 年：2016
- 卷：10
- 期：5
- 页码：5383-5390
- 全文大小：568K
- 年卷期：0
- ISSN：1936-086X
文摘
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.