The compositionally graded Ba(SnxTi1-x)O3 (BTS) films with a compositional gradient from BaTiO3 to BaSn 0.15Ti0.85O3 were fabricated on LNO-buffered Pt/Ti/SiO2/Si substrates by a sol-gel deposition method. The graded films crystallized into a pure perovskite structure after post-deposition annealing. The gradient of increasing Ti and decreasing Sn content from the surface of the film to the substrate was nicely demonstrated by the XPS data. Dielectric properties were investigated as a function of both temperature and frequency. It was observed that leakage currents increased asymmetrically for the negative and positive bias voltage with compositional gradient films. Dielectric constant peaks, common to a ferroelectric transition, were not observed in the temperature range from -25°C to 150°C. Generally, ferroelectric material is tunable in only a narrow temperature range near a phase transition. Ba(SnxTi1-x)O3 compositionally graded films with weak temperature dependence of tunability in the temperature range between -25°C and 30°C could make attractive materials for situations in which precise control of temperature would be either impossible or too expensive.
|Number of pages||9|
|State||Published - 1 Dec 2005|
|Event||Seventeenth International Symposium on Integrated Ferroelectrics, ISIF-17 - Shanghai, China|
Duration: 17 Apr 2005 → 20 Apr 2005
- BTS thin films
- Composition gradient