Journal of the Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회논문지)

The Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회)
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Ferroelectric Properties of Bi3.25La0.75Ti3O12 Thin Films with Eu Contents for Non-volatile Memory Device Application

비휘발성 메모리 소자응용을 위한 Eu 첨가량에 따른 BET 박막의 강유전 특성

  • 김경태 (중앙대학교 전자전기공학부) ;
  • 김종규 (중앙대학교 전자전기공학부) ;
  • 우종창 (중앙대학교 전자전기공학부) ;
  • 김관하 (중앙대학교 전자전기공학부) ;
  • 김창일 (중앙대학교 전자전기공학부)
  • Published : 2007.03.01
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Abstract

The effect of Eu contents on the ferroelectric properties of $Bi_{4-x}Eu_xTi_3 O_{12}$ (BET) thin films has been investigated. Bismuth Europium titanate thin films with a Eu contents were prepared on the $Pt/Ti/SiO_2/Si$ substrate by metal-organic decomposition technique. The structure and the morphology of the films were analyzed using X-ray diffraction (XRD) and field emission scanning microscopy (FE-SEM), respectively. From the XRD analysis, it was found that BET thin films have polycrystalline structure, and the layered-perovskite phase is obtained when the Eu contents exceeds 0.2 (x > 0.2). Also, the ferroelectric characteristics of the BET thin films were found to be dependent on the Eu content. Particularly, the BET films doped with x = 0.75 show better ferroelectric properties (remanent polarization 2Pr = 60.99 C/$cm^2$ and only a little polarization fatigue up to $3.5{\times}10^9$ bipolar switching cycling) than those doped with other Eu contents.

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References

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