Ferroelectric properties of Zn- and Ti-doped BiFeO3 thin films

BiFeO3 (BFO), Ti-doped BFO (BFTO), and Zn-doped BFO (BFZO) thin films were deposited on Pt(111)/Ti/SiO2/Si(100) substrates by using a pulsed laser deposition method. The effects of the substitution of Zn and Ti were investigated. Increased remnant polarization (P r ) and reduced coercive electric field (2E c ) were observed in the BFZO thin film capacitor. The values of 2P r and 2E c of the BFO, BFZO, and BFTO films were 100 µC/cm2 and 678 kV/cm, 107 µC/cm2 and 540 kV/cm, and 100 µC/cm2 and 720 kV/cm, respectively. The measured leakage current density of the BFZO thin film was approximately two orders of magnitude lower than that of the BFO thin film.