Epitaxial growth and dielectric properties of BSZT thin films on SrTiO3 : NB single crystal substrate prepared by pulsed laser deposition

摘要

The (Ba0.75Sr0.25)(Zr0.25Ti0.75)O3 (BSZT) thin films were grown on (100) SrTiO3:1.0wt.% Nb single crystal substrates by pulsed laser deposition. Highly (001)-oriented BSZT films were achieved. The thickness of as-grown thin films was measured by a surface profiler and was found to be ~600nm. The crystalline structure of the BSZT thin films on (100) SrTiO3:Nb substrate was analyzed by an X-ray diffractometer (XRD). The surface morphology and roughness were determined by an atomic force microscopy (AFM) using tapping mode amplitude modulation. The films exhibited a clustered grains characteristic of the grains with size of 80-120nm. The dielectric properties of Pt/BSZT/SrTiO3:Nb capacitors were measured by using an Agilent 4294A impedance analyzers at room temperature. The dielectric constant of BSZT film changes significantly with applied dc bias field and has a high tunability of ~44% at an applied field of 600kV/cm.