Characteristics of Ba0.8Sr0.2TiO3 ferroelectric thin films by RF magnetron sputtering

• Published in: Ceramics international 2007-09, Vol.33 (7), p.1299-1303
• Main Authors: Hu, Wencheng, Yang, Chuanren, Zhang, Wanli, Liu, Guijun
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Deposition by sputtering; Dielectric, piezoelectric, ferroelectric and antiferroelectric materials; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Exact sciences and technology; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Niobates, titanates, tantalates, pzt ceramics, etc; Physics
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2006.04.012

Ferroelectric Ba0.8Sr0.2TiO3 (BST) thin films were deposited on Pt/Ti/SiO2/Si substrates by a modified RF magnetron sputtering by introducing revolution of the workholders. XRD, Auger electron spectroscopy, atomic force microscopy and electrical measurements were used to characterise BST thin films annealed at different temperatures. Smooth and dense surfaces with homogeneous grains (about 80 nm) were seen. The electrical measurement results showed BST films annealed at 650 C had higher dielectric constant, lower loss tangent, lower leakage current and higher breakdown voltage. The curves of the temperature dependence of dielectric constant at different frequencies exhibited Curie transition at a temperature around 19 C. The remanent polarisation and the coercive field were 4.1 microC/cm2 and 60.9 kV/cm, respectively. This clearly revealed the highly promising potential of BST thin films for application in uncooled infrared focal plane arrays. 23 refs.