(1 - X) Ba (Zr 0.2 Ti 0.8) O 3-x(Ba 0.7 Ca 0.3) TiO 3 ferroelectric thin films prepared from chemical solutions

Abstract

Using chemical solution approach on Pt/Ti/SiO 2/Si substrates (1 - x)Ba(Zr 0.2Ti 0.8)O 3-x(Ba 0.7Ca 0.3)TiO 3 (BZT-BCT) ferroelectric thin films were prepared for the first time. Dense and crack-free films with perovskite structure were obtained from appropriately produced precursor solution through a multiple spin-coating process in which the individual layers were pyrolyzed at different temperatures. The effects of composition and annealing temperature on the resulting structure and properties were examined. The optimized BZT-BCT thin film exhibited a high dielectric constant of 2913 with a low dielectric loss of 0.06, and a high remnant polarization of 15.8 μC/cm 2 with a large coercive field of 58 kV/cm, and an effective piezoelectric coefficient d 33 of 71.7 pm/V under the substrate clamping. These properties are discussed in comparison with the bulk ceramic counterpart, and the results showed that the polarization rotation and strain were restricted to a large extent in the thin films. © 2011 The American Ceramic Society.