Enhanced ferroelectric properties of La-substituted BiFeO3 thin films on LaSrCoO3/Pt/TiO2/SiO2/Si (100) substrates prepared by the soft chemical method

• Published in: Ceramics international Vol. 38; no. 5; pp. 3841 - 3849
• Main Authors: Simões, A.Z., M.A.Ramirez, Foschini, C.R., Moura, F., Varela, J.A., Longo, E.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.07.2012
• Subjects: A. Films; B. Interfaces; C. Dielectric properties; C. Ferroelectric properties; C. Ferroelectric properties; A. Films; B. Interfaces; C. Dielectric properties
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2012.01.034

Bi0.85La0.15FeO3 (BLFO015) thin films were deposited by the polymeric precursor solution on La0.5Sr0.5CoO3 substrates. For comparison, the films were also deposited on Pt bottom electrode. X-ray diffraction data confirmed the substitutions of La into the Bi site with the elimination of all secondary phases under a substitution ratio x=15% at a temperature of 500°C for 2h. A substantial increase in the remnant polarization (Pr) with La0.5Sr0.5CoO3 bottom electrode (Pr≈34μC/cm2) after a drive voltage of 9V was observed when compared with the same film deposited on Pt substrate. The leakage current behavior at room temperature decreased from 10−8 (Pt) to 10−10A/cm2 on (La0.5Sr0.5CoO3) electrode under a voltage of 5V. The fatigue resistance of the Au/BLFO015/LSCO/Pt/TiO2/SiO2/Si (100) capacitors with a thickness of 280nm exhibited no degradation after 1×108 switching cycles at a frequency of 1MHz.