Role of the $Bi_2O_3\;in\;SrBi_2TaNbO_9/Bi_2O_3/SrBi_2TaNbO_9$ Heterostructure and Low Temperature Annealing Property

  • Park, Yoon-Beak (Thin Film Technology Research Center, Korea Institute of Science and Technology, Department of Analysis, Memory Product & TEchnology, Developement Division, Hyundai Electronics Industries Co., Ltd.) ;
  • Jang, Se-Myeong (Thin Film Technology Research Center, Korea Institute of Science and Technology) ;
  • Kim, Ju-Hyung (Thin Film Technology Research Center, Korea Institute of Science and Technology) ;
  • Lee, Jeon-Kook (Thin Film Technology Research Center, Korea Institute of Science and Technology) ;
  • Park, Jong-Wan (Department of Metallurgical Engineering, Hanyang University)
  • Published : 2000.09.01

Abstract

Ferroelectric properties of $SrBi_2TaNbO_9$ (SBTN) thin films were changed by the amount of Bi content in SBTN. We suggested that the addition of excess Bi into the films could be accomplished by heat-treating $SBTN/Bi_2O_3/SBTN$ heterostructure fabricated by r.f. magnetron sputtering method. Excess Bi composition was controlled by the thickness of the sandwiched $Bi_2O_3$ from 0 to $400\;\AA$. When the SBTN thin films were inserted by $400\;{\AA}\;Bi_2O_3$ layer, $Bi_2Pt$ phase was formed as a second phase in SBTN films, resulting in poor ferroelectric properties. The onset temperature for hysteresis loop can be reduced by heat treating $SBTN/Bi_2O_3/SBTN$ heterostructure. The films with $SBTN/Bi_2O_3(100\;{\AA})/SBTN$ hetero-structure followed by annealing at $650^{\circ}C$ for 30 min show 2Pr and Ec of $5.66\;{\mu}C/\textrm{cm}^2$ and 54 kV/cm, respectively.

Keywords

References

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