Ferroelectric Properties of Tungsten-Substituted Bi4Ti3O12Thin Film Prepared by Sol–Gel Method

Jin Soo Kim, Sang Su Kim, Jong Kuk Kim, Tae Kwon Song
2002 Japanese Journal of Applied Physics  
Bi 4 Ti 3 O 12 (BIT) and tungsten-substituted Bi 4 Ti 3 O 12 (BTW) thin films were prepared on Pt/Ti/SiO 2 /Si substrates by a sol-gel method. There are differences in the ferroelectric properties and grain strucure between BIT and BTW thin films. The crystal structure and the surface grain morphology were characterized by scanning electron microscopy and X-ray diffraction. Grains of BIT were grown with c-axis preferred orientation, while these of the BTW were randomly distributed. The
more » ... tric properties and polarization fatigue characteristics were confirmed by the P{E hysteresis loops. The BTW thin film was measured to have remanent polarization (2P r ) of 27 C/cm 2 and a coercive field (2E c ) of 130 kV/cm. The dielectric constant and loss tangent at 1 MHz were measured as 210 and 0.05, respectively. On adding a small amount of tungsten in Bi 4 Ti 3 O 12 , the remanent polarization increased and fatigue resistance improved.
doi:10.1143/jjap.41.6451 fatcat:w6llpbyudfamfk5sl77pbzvaxi