Enhanced electrical properties of <i>c</i>-axis epitaxial Nd-substituted Bi4Ti3O12 thin films

Abstract

High-quality c-axis epitaxial ferroelectric thin films of Bi4Ti3O12 (BTO) and Nd-substituted BTO, Bi3.15Nd0.85Ti3O12 (BNT), were prepared on (001)-LaNiO3-coated (001) LaAlO3 substrates by pulsed-laser deposition. The epitaxial alignments were established by the x-ray diffraction, including θ–2θ and φ scans. Compared to the BTO films, the BNT films have significantly improved electrical properties with about 2 times larger remanent polarization, 0.6 times lower coercive field, better fatigue-resisting characteristics, and 1.7 times larger dielectric constant. These results showed experimentally that Nd substitution could enhance the c-axis electrical properties of BTO. The reason for the improved properties of BNT films was discussed.