Large remnant polarization and excellent fatigue property of vanadium-doped SrBi4Ti4O15 thin films

We report the enhancement of electric and fatigue-endurance properties of vanadium-doped SrBi4Ti4O15 (SBTi) thin films deposited by a refined sol-gel method. The structures and surface morphologies of the films were characterized by x-ray diffraction, atomic force microscopy, and scanning electron microscopy. Their electric properties were investigated systematically. Compared to the undoped SBTi, V-doped SBTi [(SrBi3.99Ti3.97V0.03O15) (SBTV)] showed a larger remnant polarization (2P(r)), lower coercive electric field, lower leakage current density, and a better fatigue resistance. The 2P(r) of SBTV was 35.9 mu C/cm(2), which was much higher than that of SBTi (25.3 mu C/cm(2)). Importantly, at a low frequency of 50 kHz, the SBTV film showed no variation of P-nv and -P-nv after 2.2x10(9) switching cycles, suggesting excellent fatigue-endurance characteristics. (c) 2006 American Institute of Physics.