Electrical behavior of BaZr0.1Ti0.9O3 and BaZr0.2Ti0.8O3 thin films

BaZr0.1Ti0.9O3 and BaZr0.2Ti0.8O3 (BZT) thin films were deposited on Pt/Ti/LaAlO3 (1 0 0) substrates by radio-frequency magnetron sputtering, respectively. The films were further annealed at 800 °C for 30 min in oxygen. X-ray diffraction θ-2θ and Φ-scans showed that BaZr0.1Ti0.9O3 films displayed a highly (h 0 0) preferred orientation and a good cube-on-cube epitaxial growth on the LaAlO3 (1 0 0) substrate, while there are no obvious preferential orientation in BaZr0.2Ti0.8O3 thin films. The BaZr0.1Ti0.9O3 films possess larger grain size, higher dielectric constant, larger tunability, larger remanent polarization and coercive electric field than that of BaZr0.2Ti0.8O3 films. Whereas, BaZr0.1Ti0.9O3 films have larger dielectric losses and leakage current density. The results suggest that Zr4+ ion can decrease dielectric constant and restrain non-linearity. Moreover, the enhancement in dielectric properties of BaZr0.1Ti0.9O3 films may be attributed to (1 0 0) preferred orientation.