Correlation between the composition, phase, band structure, ferroelectric and leakage responses of Bi1-xBaxFe1-yTiyO3 thin films

• Published in: Thin solid films 2022-09, Vol.758, Article 139448
• Main Authors: Mumtaz, Fiza, Khan, Muhammad Haroon, Jaffari, G. Hassnain
• Format: Article
• Language: English
• Subjects: Band gap; Bismuth Ferrite; Chemical solution deposition; Leakage conduction mechanism; Mixed phase; Thin film
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2022.139448

•Synthesis optimization to achieve correct phase.•Substitution reduces Bi3+ volatilization, stabilizes structural phase and leakage.•Resistive and dielectric characteristics identified in Polarization hysteresis.•Mechanisms of leakage current have been identified and discussed.•Schematic band diagram with and without substituent have been constructed. Despite significant attention given to multiferroics, they are still far from being used in practical applications. This is because high electrical leakage current limited their use on a commercial scale. The current work demonstrates the effect of substitution in reducing leakage current and improving the electrical properties of BiFeO3 films. Chemical solution deposition method is used to prepare substituted and co-substituted thin-films of BiFeO3 on fluorine doped tin oxide glass substrate. Detailed structural analysis of synthesis optimization has been characterized, including X-ray diffraction and Raman analysis. Polarization hysteresis loops exhibit resistive characteristics, indicating leakage behavior. Specifically, high leakage current is observed in BiFeO3 thin film. Detailed analysis revealed the presence of ohmic and space charge limited conduction mechanisms. Substitution of Ba2+ for Bi3+ reduces Bi3+ volatilization and suppresses the leakage current. The co-substitution of Ba2+ and Ti4+ is observed to be effective in reducing leakage characteristics in films.