Effect of annealing on ferroelectric properties of Bi_3.25La_0.75Ti₃O₁₂ thin films prepared by the sol-gel method

Abstract

Bi_3.25La_0.75Ti₃O₁₂(BLT) thin films were prepared on Pt/Ti/SiO₂/Si substrate by the sol-gel method. The effect of annealing on their structures and ferroelectric properties was investigated. The XRD patterns indicate that the BLT films annealed at different temperatures are randomly orientated and the single perovskite phase is obtained at 550°C. The remnant polarization increases and the coercive field decreases with the annealing temperature increasing. The leakage current density of the BLT films annealed at 700°C is about 5.8×10⁻⁸ Al cm² at the electric field of 250 kV/cm.

Keywords

Bi_3.25La_0.75Ti₃O₁₂ / ferroelectric thin film / sol-gel method / leakage current

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