Structure and Electrical Properties of Na0.5Bi0.5TiO3 Epitaxial Films with (110) Orientation

• Published in: Crystals (Basel) Vol. 9; no. 11; p. 558
• Main Authors: Song, Jianmin, Gao, Jie, Zhang, Suwei, Luo, Laihui, Dai, Xiuhong, Zhao, Lei, Liu, Baoting
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01-11-2019
• Subjects: Bismuth titanate; Capacitors; Current density; Electric fields; Electrical properties; Electrodes; Epitaxial growth; Fatigue strength; Ferroelectric materials; ferroelectric properties; Ferroelectricity; Lasers; Leakage current; Microelectromechanical systems; nbt epitaxial film; Polarization; Random access memory; Space charge; Strontium titanates; Substrates; ultraviolet light; Ultraviolet radiation; China
• ISSN: 2073-4352; 2073-4352
• DOI: 10.3390/cryst9110558

Pt/Na0.5Bi0.5TiO3/La0.5Sr0.5CoO3 (Pt/NBT/LSCO) ferroelectric capacitors were fabricated on (110) SrTiO3 substrate. Both NBT and LSCO films were epitaxially grown on the (110) SrTiO3 substrate. It was found that the leakage current density of the Pt/NBT/LSCO capacitor is favorable to ohmic conduction behavior when the applied electric fields are lower than 60 kV/cm, and bulk-limited space charge-limited conduction takes place when the applied electric fields are higher than 60 kV/cm. The Pt/NBT/LSCO capacitor possesses good fatigue resistance and retention, as well as ferroelectric properties with Pr = 35 μC/cm2. The ferroelectric properties of the Pt/NBT/LSCO capacitor can be modulated by ultraviolet light. The effective polarization, ΔP, was reduced and the maximum polarization Pmax was increased for the Pt/NBT/LSCO capacitor when under ultraviolet light, which can be attributed to the increased leakage current density and non-reversible polarization P^ caused by the photo-generated carriers.