Dielectric and Electrical Properties of <TEX>$Sr_{0.9}Bi_{2+x}Ta_2O_9$</TEX> Thin Films on <TEX>$IrO_2$</TEX> Electrode

,; ,; ,; ,; ,; ,; ,; ,

J. Korean Ceram. Soc. > Volume 37(3); 2000 > Article

Journal of the Korean Ceramic Society 2000;37(3): 233.

$IrO_2$를 하부전극으로 사용한 $Sr_{0.9}Bi_{2+x}Ta_2O_9$ 박막의 유전 및 전기적 특성

박보민, 송석표, 정병직, 김병호

고려대학교 재료공학과

Dielectric and Electrical Properties of $Sr_{0.9}Bi_{2+x}Ta_2O_9$ Thin Films on $IrO_2$ Electrode

ABSTRACT

Sr0.9Bi2+xTa2O9(x=0, 0.1, 0.2, 0.3) thin films on IrO2/SiO2/Si or Pt/Ti/SiO2/Si substrate were prepared by spin coating method using SBT stock solutions synthesized by MOD process. SBT thin films on IrO2 transformed to layered perovskite phase at $700^{circ}C$, but showed low breakdown voltage due to their porous microstructure. The smaple of Sr0.9Bi2+xTa2O9 composition showed the best dielectric and electrical properties. When the sample of the same composition was annealed at 80$0^{circ}C$, the dielectric and electric properties were improved due to the grian growth and dense surface. the remanent polarization values(2Pr) at $pm$3 V for IrO2 and Pt electrodes were 10.5, 7.15$mu$C/$textrm{cm}^2$, respectively. The SBT thin film with IrO2 electrode showed the lower coercive field. The leakage current density and breakdown voltage of SBT thin films on IrO2 were higher than those on Pt.

Key words: MOD, SBT thin film, $IrO_2$ electrode, Layered perovskite