Powders and thin films of barium sodium niobate, Ba4Na2Nb10O30, of filled tungsten bronze type ferroelectric were processed by a sol-gel route using barium metal, niobium ethoxide and sodium methoxide as precursors. Polycrystalline powder resulted after heat treating the gel powder at or above 650°C. Thin films of Ba4Na2Nb10O30 showed no preferred orientation on Si(100), Pt/Si(100) and sapphire substrates. Hysteresis measurements at 1 kHz for the thin films annealed at 750°C, obtained using a prehydrolyzed precursor solution, and gave remanent polarization of 17.34 μC/cm2 and coercive field of 62.5 kV/cm. Microstructural investigation of surface morphology of these films revealed grains about 0.3 μm in size. Prehydrolysis of the precursor solution was found to be necessary to achieve dense films with ferroelectric properties.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Condensed Matter Physics
- Materials Chemistry