Effects of La2O3 and Ta2O5 on the PTCR Characteristics in Molten Salt Synthesized BaTiO3

용융염 합성법에 의한 BaTiO3의 PTCR특성에 미치는 La2O3와 Ta2O5의 영향

  • 윤기현 (연세대학교 요업공학과) ;
  • 김동영 (연세대학교 요업공학과) ;
  • 윤상옥 (연세대학교 요업공학과)
  • Published : 1988.03.01


The effects of flux KCl and dopants, La2O3 and Ta2O5, on the PTCR characteristics in molten salt synthesized BaTiO3 have been studied. The resistivity of BaTiO3 at room temperature decreases with increasing amount of dopant La2O3 up to 0.2 atom%, and then increases with La2O3 content. In case of dopant Ta2O5, it increases with increasing amount ofthe dopant. These results could be explained by observation of the microstructure and defect equation. From the results of complex impedance-frequency characteristics, the grain resistances are almost same but the resistances at the grain boundary are quite different.



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