Influence of the vicinal surface on the anisotropic dielectric properties of highly epitaxial Ba0.7Sr0.3TiO3 thin films

Guang Yao; Yanda Ji; Weizheng Liang; Min Gao; Shengliang Zheng; You Wang; Handong Li; Zhiming Wang; Chonglin Chen; Yuan Lin

doi:10.1039/c6nr09044c

Influence of the vicinal surface on the anisotropic dielectric properties of highly epitaxial Ba_0.7Sr_0.3TiO₃ thin films

Nanoscale. 2017 Mar 2;9(9):3068-3078. doi: 10.1039/c6nr09044c.

Authors

Affiliations

¹ State Key Laboratory of Electronic Thin films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, P. R. China. linyuan@uestc.edu.cn.
² Department of Materials Physics and Chemistry, Harbin Institute of Technology, Harbin 150001, P. R. China.
³ Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, Texas 78249, USA.

PMID: 28191570
DOI: 10.1039/c6nr09044c

Abstract

Epitaxial thin films of Ba_0.7Sr_0.3TiO₃ (BST) were grown on the designed vicinal single-crystal LaAlO₃ (001) substrates to systematically investigate the evolution of microstructures and in-plane dielectric properties of the as-grown films under the strains induced by surface step terraces. Anisotropic dielectric properties were observed, which can be attributed to different tetragonalities induced by vicinal LaAlO₃ substrates with miscut orientations along the [100] and [110] directions with different miscut angles of 1.0°, 2.75° and 5.0°. A terrace geometric model with both compressive and tensile strained domains in the BST film was established, which is in good agreement with the experimental results. Our experimental studies not only shed new light on the heteroepitaxial growth mechanism, but also provide a promising platform for the design and integration of high performance device applications.