Percolative nanoparticle-Ag/PbZr0.52Ti0.48O3 composite thin film with high dielectric and ferroelectric properties

Abstract

Agx/PbZr0.52Ti0.48O3 (PZT, x defined as mole ratio of Ag/Pb) composite thin films were fabricated by the sol–gel technique. Results showed that the Agx/PZT thin films were composed of perovskite phase of PZT and silver nanoparticles. The silver nanoparticles with size between 4.5 and 7 nm were uniformly dispersed in the thin films. The percolation behavior occurred in the Ag/PZT thin films. The properties of PZT thin film were significantly improved as silver was introduced, especially as the fraction of silver nanoparticles was near the percolation threshold. The relative permittivity of the percolative Ag0.7/PZT thin film was 230 % higher than that of the single phased PZT thin film. The tunability of the percolative Ag0.7/PZT thin film was 57 % higher than that of the single phased PZT thin film. Meanwhile, the operating voltage for Ag0.7/PZT thin film supplying optimal tunability was only ~3 V (120 kV/cm), which was reduced by about 45 % compared to the single phased PZT thin film. The remanent polarization value of the Ag0.7/PZT percolative thin film was 22.9 μC/cm2, which was about 26 % higher than that of the single phased PZT thin film. While the coercive field of the Ag0.7/PZT percolative thin film was reduced by 29 %. It is attractive to be used as an electronic thin film with high performance.