Study on Microstructure and Ferroelectricity of Strontium Barium Titanate Thin Films Prepared by Sol-Gel Processing

Abstract:

Sr_0.5Ba_0.5-xBi_xTiO₃ (SBT) thin films were fabricated on a Pt/SiO₂/Si substrate by sol-gel method. The effects of chelating agent acetylacetone (HAcHAc) on the formation temperature and the microstructure of Sr_0.5Ba_0.5-xBi_xTiO₃ (SBT) thin films were investigated in this paper. The microstructure of BST thin films was examined by XRD and TEM. It is found that Bi³⁺ doping decreases dielectric loss, improves frequency dispersion for BST thin films. The peak of temperature-dependence of dielectric constant of Bi³⁺-doped BST thin films is compressed and moves to a low-temperature region. An inclined angle of approximately 1.8o between the two different polarization vectors was observed for BST thin film from the results of high-resolution transmission electron microscopy (HRTEM). The Pr, Ps and Ec was 0.22μC/cm², 0.72μC/cm² and 60Kv/cm respectively for Sr_0.5Ba_0.485Bi_0.015TiO₃ thin film at 100Hz, 20V.

• Periodical: Applied Mechanics and Materials (Volume 320)
• Pages: 202-207
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.320.202
• Online since: May 2013
• Authors: Lian Wei Shan, Lai Guo Wang, Wei Li, Li Min Dong, Zhi Dong Han, Ze Wu, Xing Hua Fu, Wen Ping Hou
• Keywords: Bi-Doping, Ferroelectricity, SBT, Thin Film

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