Preparation and ferroelectric properties of (Na0.5Bi0.5)0.94Ba0.06TiO3 thin films deposited on Pt electrodes using LaNiO3 as buffer layer

(Na0.5Bi0.5)0.94Ba0.06TiO3 thin films were deposited on Pt/Ti/SiO2/Si (1 1 1) and LaNiO3/Pt/Ti/SiO2/Si (1 1 1) substrates by a sol–gel process. The phase structure and ferroelectric properties were investigated. The X-ray diffraction pattern indicated that the (Na0.5Bi0.5)0.94Ba0.06TiO3 thin film deposited on Pt/Ti/SiO2/Si (1 1 1) substrates is polycrystalline structure without any preferred orientation. But the thin film deposited on LaNiO3/Pt/Ti/SiO2/Si substrates shows highly (1 0 0) orientation (f ≥ 81%). The leakage current density for the two thin films is about 6 × 10−3 A/cm2 at 250 kV/cm, and thin film deposited on LaNiO3/Pt/Ti/SiO2/Si substrates possessed a much lower leakage current under high electric field. The hysteresis loops at an applied electric field of 300 kV/cm and 10 kHz were acquired for the thin films. The thin films deposited on LaNiO3/Pt/Ti/SiO2/Si substrates showed improved ferroelectricity.