FATIGUE AND SWITCHING PROPERTIES OF THE BLT THIN FILMS PREPARED BY SOL-GEL METHOD

ABSTRACT Fatigue and switching properties of BLT thin films fabricated on Pt/TiOx/SiO2/Si substrates were investigated. Prepared films showed the strong (117) peak denoting Bismuth layered structure and the peaks representing c-axis orientation. The thickness of BLT thin films was about 240 nm and the densities of the elements Bi, La, Ti and O exhibited the relatively uniform distribution. The dielectric constant and loss of BLT thin films measured at 100 kHz were 292 and 0.07 respectively. The remanent polarization (2Pr) and coercive field (2Ec) of BLT thin films were 9.92 μ C/cm2 and 143 kV/cm respectively with applied electric field of 208 kV/cm, and the difference of switching polarization (P∗) and non-switching polarization (P∧) had a decrease of approximately 15% of its initial value after 109 switching cycles. The switching time decreased from 0.61 μ s to 0.22 μ s as the input pulse voltage increased from 2 V to 5 V. As the load resistance increased from 50 Ω to 3.3 kΩ, the switching time increased...