Dielectric, ferroelectric and optical properties of BaZr0.2Ti0.8O3 thin films prepared by sol–gel-hydrothermal process

• Published in: Journal of sol-gel science and technology 2010-09, Vol.55 (3), p.343-347
• Main Authors: Xu, J. B., Shen, B., Zhai, J. W.
• Format: Article
• Language: English
• Subjects: Ceramics; Chemistry; Chemistry and Materials Science; Coercive force; Coercivity; Colloidal gels. Colloidal sols; Colloidal state and disperse state; Composites; Constants; Dielectric loss; Dielectric properties; Dielectric strength; Exact sciences and technology; Ferroelectric materials; Ferroelectricity; Frequency ranges; General and physical chemistry; Glass; Infrared; Inorganic Chemistry; Materials Science; Nanotechnology; Natural Materials; Optical and Electronic Materials; Optical properties; Original Paper; Silicon; Silicon dioxide; Silicon substrates; Sol-gel processes; Spectroellipsometry; Thin films; Titanium
• ISSN: 0928-0707; 1573-4846
• DOI: 10.1007/s10971-010-2259-9

BaZr 0.2 Ti 0.8 O 3 thin films on Pt/Ti/SiO 2 /Si substrates have been fabricated under low temperature conditions by a sol–gel-hydrothermal technique. The dielectric constant is 247–83 in the frequency range of 1 kHz–1 MHz. The corresponding dielectric loss is ~10 −2 . The capacitance–voltage curve shows strong non-linear dielectric behavior leading to a high tunability, up to ~30% at 1 kHz. The remanent polarization and coercive field at room temperature are measured to be ~1.5 μC/cm 2 and ~90 kV/cm. The infrared optical properties of the thin films are investigated using an infrared spectroscopic ellipsometry in the wave number range of 800–4,000 cm −1 . Optical constants of the thin films are simultaneously obtained.