Structural and Electrical Properties of PZT(10/90)/PZT(90/10) Heterolayered Thin Films

PZT(10/90)/PZT(90/10) 이종층 박막의 구조적, 전기적 특성

  • 이성갑 (서남대 전자전기공학과) ;
  • 김경태 (광운대 전자재료공학과 졸업) ;
  • 배선기 (시립인천대 전기공학과) ;
  • 이영희 (광운대 전자재료공학과)
  • Published : 2000.02.01

Abstract

Ferroelectric PZT heterolayered thin films were fabricated by spin coating method on the Pt/Ti/SiO2/Si substrate using PZT(10/90) and PZT(90/10) m7etal alkoxide solutions. All PZT heterolayered films showed a homogeneous grain structures without presence of rosette structure. It can be assumed that the lower PZT layers played a role of nucleation site for the formation of the upper PZT layer. Pb-deficient PZT phase was formed at PZT/Pt interface due to the diffusion of Pb element into a Pt bottom electrode. The relative dielectric constant and the dielectric loss of the PZT-6 film were 567 and 3.6%, respectively. Increasing the number of coatings, remanent polarization and coercive field were decreased and the values of the PZT-6 heterolayered film were $7.18\muC/cm^2$ and 68.5kV/cm, respectively. Leakage current densities were increased with increasing the number of coatings, and the value of the PZT-4 film was about $7\times10-8A/cm^2$ at 0.05MV/cm.

Keywords

References

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