Structures and electrical properties of Bi5FeTi3O15 thin films -: art. no. 104106

Thin films of layered ferroelectric oxide Bi5FeTi3O15 have been fabricated on Pt-coated Si substrates by pulsed laser deposition. Temperature-dependent Raman studies reveal the phase-transition temperature of 550 degrees C, consistent with other reports. A new mode at 685 cm(-1) is observed and ascribed to the Bi-Fe-O perovskite block. With an applied field of 105 kV/cm, the leakage current density is 5.2 x 10(-7) A/cm(2), indicating the high room-temperature resistivity in the order of 10(12) Omega cm. With an applied external electric field of 210 kV/cm, the remnant polarization and coercive field of the films are measured to be 6.4 mu C/cm(2) and 112 kV/cm, respectively. The nonvolatile polarization of the films decreases about 15% of the initial value after 7.2 x 10(9) switching cycles. As for the dielectric properties, at 0.1 MHz, the measured dielectric constant and loss tangent are 172 and 0.024, respectively. The ferroelectric properties are comparable with that of other Bi-layered oxides, such as rare-earth substituted Bi4Ti3O12 films, which are promising candidates for application in ferroelectric memory. (c) 2005 American Institute of Physics.