The ferroelectric properties and residual stress analysis of Bi3.15Nd0.85Ti3O12 thin films with a LaNiO3 buffer layer

Abstract

Bi3.15Nd0.85Ti3O12 (BNT) thin film with a thin LaNiO3 film as buffer layer was fabricated by sol–gel method on Pt/TiO2/SiO2/Si substrate. The BNT thin films have a perovskite phase with a dense microstructure. The P r and V c value are 25.5 μc/cm2 and 3.7 V, respectively under the applied voltage of 15 V. After the switching of 2 × 109 cycles, the P r value decreases to 86% of its pre-fatigue value. The leakage current density of the BNT thin films with LaNiO3 buffer layer were generally in the order of 10−8 to 10−6 A/cm2. The fatigue and leakage current properties were improved dramatically compared with the BNT film without a LaNiO3 buffer layer that we prepared before. The measured residual stress was tensile stress and its value was 176 MPa.