Dielectric and ferroelectric properties of (100)-oriented 0.9Pb(Sc0.5Ta0.5)O3 -0.1%PbTiO3/0.55Pb(Sc0.5Ta0.5)O3-0.45%PbTiO3 heterostructures

The 0.9Pb(Sc0.5Ta0.5)O3-0.1%PbTiO3/0.55Pb(Sc0.5Ta0.5)O3-0.45%PbTiO3 (PSTT10/PSTT45) multilayer thin films were deposited on SiO2/Si(1 0 0) substrates by radio frequency magnetron sputtering technique with a LaNiO3 buffer layer, and the films were subsequently annealed by a two-steps rapid thermal approach. With this method, the films possess a highly (1 0 0) orientation, which is attributed to the introduction of LaNiO3 buffer layer. Enhanced dielectric and ferroelectric properties were observed in the multilayer thin films with low anneal temperatures of 700-750 °C. Typically, the films annealed at 700 °C have a high dielectric constant of ∼698.5 and a low dielectric loss of 0.054. In addition, such a thin film also exhibits a large remnant polarization of 5.45 μC/cm2. The crystallization, the percentage pyrochlore and the loss of Pb are considered to play an important role on electric properties of the films.