Ferroelectric and Electrical Properties Optimization of Mg-doped BiFeO3 Flexible Multiferroic Films

• Published in: Symmetry (Basel) Vol. 12; no. 7; p. 1173
• Main Authors: Lin, Der-Yuh, Chen, Hone-Zern, Kao, Ming-Cheng, Zhang, Pei-Li
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01-07-2020
• Subjects: Bending; Bismuth ferrite; Coated electrodes; Dielectric properties; Electric fields; Electrical properties; ferroelectric; Ferroelectric materials; Ferroelectricity; Ferroelectrics; flexible; Grain size; Leakage; leakage current; Magnesium; multiferroic films; Multiferroic materials; Optimization; Optoelectronic devices; polarization; retention; Sol-gel processes; Spin coating; Stainless steels
• ISSN: 2073-8994; 2073-8994
• DOI: 10.3390/sym12071173

Bi1-xMgxFeO3 (BMFO, x = 0, 0.02, 0.04, 0.06 and 0.08) multiferroic films were directly synthesized on flexible stainless steel (FSS), save the bottom electrode process, by means of sol–gel spin-coating technology. The effects of different bending conditions on ferroelectric, dielectric and leakage-current properties of BMFO films were investigated. The leakage-current densities of BiFeO3 (BFO, x = 0) and BMFO (x = 0.06) films were 5.86 × 10−4 and 3.73 × 10−7 A/cm2, which shows that the BMFO (x = 0.06) has more than three orders of magnitude lower than that of BFO film. The residual polarization (2 Pr) can be enhanced from 120 to 140 μC/cm2. The proper doping of Mg in BiFeO3 film could provide an effective method for reducing the leakage-current values as well as boosting the ferroelectric properties. In this study, the leakage-current mechanism of low electric field and high electric field of BMFO film is analyzed and established. In addition, the flexible BMFO film maintains practical ferroelectric and leakage-current properties at retention time of 106 s under different symmetry bending conditions. These results indicate that the BFMO film will be very practical in opto-electronic and storage device applications.