S. Trolier-McKinstry—contributing editor
Enhanced Structures and Electrical Properties of Lead-Free K0.5Na0.5NbO3–Bi0.5Na0.5TiO3 0–3 Composite FerroelectricThick Films
Article first published online: 2 MAY 2011
© 2011 The American Ceramic Society
Journal of the American Ceramic Society
Volume 94, Issue 10, pages 3425–3430, October 2011
How to Cite
Ji, H., Ren, W., Wang, L., Shi, P., Chen, X., Wu, X., Yao, X., Lau, S.-T., Zhou, Q. and Shung, K. K. (2011), Enhanced Structures and Electrical Properties of Lead-Free K0.5Na0.5NbO3–Bi0.5Na0.5TiO3 0–3 Composite FerroelectricThick Films. Journal of the American Ceramic Society, 94: 3425–3430. doi: 10.1111/j.1551-2916.2011.04524.x
This work was financially supported by the Natural Science Foundation of China (Grant No. 90923001), International Science & Technology Cooperation Program of China (Grant No. 2010DFB13640), the Shaanxi Province International Collaboration Program (Grant Nos. 2009KW-12 and 2010KW-09), and the NIH Grant P41-EB2182.
- Issue published online: 4 OCT 2011
- Article first published online: 2 MAY 2011
- Manuscript No. 28582. Received September 9, 2010; approved February 21, 2011.
Lead-free K0.5Na0.5NbO3–Bi0.5Na0.5TiO3 (KNN–BNT) 0–3 composite ferroelectric thick films have been successfully prepared by a modified composite sol–gel process. The KNN fine ceramic powders were dispersed in the BNT precursor solution to form the uniform slurry that was spin coated on (111) Pt/TiO2/SiO2/Si substrates. The buffer layers and vacuum infiltration were used during the deposition process to improve the structure and density of the composite films. Influence of the annealing temperature and weight ratio of the powder-to-solution on the structures and electrical properties of KNN–BNT composite thick films has been investigated. X-ray diffraction analysis indicates that the composite thick films possess pure perovskite structures composed by KNN and BNT phases. The dielectric constant and remnant polarization of the composite thick films increase with increasing annealing temperature and decreasing powder-to-solution weight ratio due to reduction of pores and improvement of film density. The composite thick films with the powder-to-solution weight ratio of 0.40 and annealed at 750°C have a dielectric constant of 848 and a remnant polarization of 23.6 μC/cm2. The KNN–BNT composite thick films obtained are a promising candidate for transducer applications.