Electrical Characterization and Microstructures of Bi_4-xGd_xTi₃O₁₂ Thin Films

Abstract:

Gd2O3-doped bismuth titanate (Bi4-xGdxTi3O12: BGT) and pure Bi4Ti3O12 (BIT) thin films with random orientation were fabricated on Pt/Ti/SiO2/Si substrates by rf magnetron sputtering technique. These samples had polycrystalline Bi-layered perovskite structure without preferred orientation, and consisted of well developed rod-like grains with random orientation. Gd-doping into BIT caused a large shift of the Curie temperature ( TC ) from 675 °C to lower temperature and a improvement in dielectric property. The experimental results indicated that Gd doping into BIT also result in a remarkable improvement in ferroelectric property. The Pr and the Ec values of the BGT film with x=0.75 were 28 μC/cm2 and 65 kV/cm, respectively.

• Periodical: Key Engineering Materials (Volume 633)
• Pages: 257-260
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.633.257
• Online since: November 2014
• Authors: Min Chen, X.A. Mei, J. Liu
• Keywords: Bismuth Titanate, Dielectric, Ferroelectric, Film

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