Structural evolution of nanostructured barium titanate thin film sol–gel derived

• Published in: Journal of sol-gel science and technology 2008-02, Vol.45 (2), p.125-132
• Main Authors: RADONJIC, L, TODOROVIC, M, MILADINOVIC, J
• Format: Article
• Language: English
• Subjects: Barium; Barium hydroxide; Barium titanates; Ceramics; Chemistry; Chemistry and Materials Science; Colloidal gels. Colloidal sols; Colloidal state and disperse state; Composites; Crystal structure; Crystallinity; Crystallization; Evolution; Exact sciences and technology; Ferroelectric materials; Ferroelectricity; General and physical chemistry; Glass; Hydroxides; Infrared spectroscopy; Inorganic Chemistry; Materials Science; Nanostructure; Nanotechnology; Natural Materials; Optical and Electronic Materials; Original Paper; Precursors; Silicon substrates; Sol-gel processes; Thin films; X-ray diffraction
• ISSN: 0928-0707; 1573-4846
• DOI: 10.1007/s10971-007-1664-1

Ferroelectric nanostructured barium titanate (BT) thin films derived by a modified sol–gel process were formed by a deep coating method on Si (100) substrate. In this work was investigated the influence of different types and amounts of water (free water directly added in process and crystalline water from barium precursors) and of different barium precursors (hydroxide and acetate) on the gel-structure evolution and the barium titanate thin film crystallization. The IR-spectroscopy and X-ray diffraction analysis were used for sample characterization. Experimental results show that crystalline water from barium hydroxide octahydrate stabilizes the cubic phase of barium titanate. Barium titanate crystallizes in the tetragonal form in thin films when sols were prepared with free water and Ba-acetate or Ba-hydroxide monohydrate as precursors. The type of Ba-precursor used in preparation of sols effects the rate of crystallization of the BT in thin films, making it slower in the case when as precursor was used Ba-acetate than Ba-hydroxides. The prepared BT-thin films demonstrated good adhesion towards substrate and were smooth and uniform.