Bein Benjamin, Hsing Hsiang-Chun, Callori Sara J, Sinsheimer John, Chinta Priya V, Headrick Randall L, Dawber Matthew
Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794-3800, USA.
Department of Physics, Cook Physical Science Building, University of Vermont, Burlington, Vermont 05405, USA.
Nat Commun. 2015 Dec 4;6:10136. doi: 10.1038/ncomms10136.
In epitaxially strained ferroelectric thin films and superlattices, the ferroelectric transition temperature can lie above the growth temperature. Ferroelectric polarization and domains should then evolve during the growth of a sample, and electrostatic boundary conditions may play an important role. In this work, ferroelectric domains, surface termination, average lattice parameter and bilayer thickness are simultaneously monitored using in situ synchrotron X-ray diffraction during the growth of BaTiO3/SrTiO3 superlattices on SrTiO3 substrates by off-axis radio frequency magnetron sputtering. The technique used allows for scan times substantially faster than the growth of a single layer of material. Effects of electric boundary conditions are investigated by growing the same superlattice alternatively on SrTiO3 substrates and 20 nm SrRuO3 thin films on SrTiO3 substrates. These experiments provide important insights into the formation and evolution of ferroelectric domains when the sample is ferroelectric during the growth process.
在 epitaxially strained 铁电薄膜和超晶格中，铁电转变温度可能高于生长温度。那么，在样品生长过程中铁电极化和畴应该会演化，并且静电边界条件可能起重要作用。在这项工作中，通过离轴射频磁控溅射在 SrTiO3 衬底上生长 BaTiO3/SrTiO3 超晶格时，使用原位同步加速器 X 射线衍射同时监测铁电畴、表面终止、平均晶格参数和双层厚度。所使用的技术允许扫描时间比单层材料的生长速度快得多。通过在 SrTiO3 衬底和 SrTiO3 衬底上的 20 nm SrRuO3 薄膜上交替生长相同的超晶格来研究电边界条件的影响。这些实验为样品在生长过程中为铁电体时铁电畴的形成和演化提供了重要见解。
