Effect of Li Addition on the Microwave Dielectric Propertis of $MgTiO_3$-$CaTiO_3$ ceramic Dielectrics

Li을 첨가한 $MgTiO_3$-$CaTiO_3$계 세라믹 유전체의 마이크로파 유전특성

  • 한진우 (한국전자통신연구원 세라믹RF부품팀) ;
  • 김동영 (한국전자통신연구원 세라믹RF부품팀) ;
  • 전동석 (한국전자통신연구원 세라믹RF부품팀) ;
  • 이상석 (한국전자통신연구원 세라믹RF부품팀)
  • Published : 2001.03.01

Abstract

The microwave dielectric properties and a sintering behavior of MgTiO$_3$-CaTiO$_3$ ceramics doped with Li were investigated. The main composition was fixed as 0.94MMgTiO$_3$-0.06CaTiO$_3$ and Li$_2$CO$_3$was added excessively in the range of 0~10 mol% (with reference to Li atoms) and the specimens were sintered at 1200~140$0^{\circ}C$ for 4 hours. When the amount of Li was small the quality factor and dielectric constant were reduced, while those tow properties increased if the Li amount was above 1 mol%. But if Li was overly added those dielectric properties decreased again. Li, if added in the composition range of 1.0~3.0 mol%, can increase the quality factor of MgTiO$_3$-CaTiO$_3$ ceramics. The optimum amount of Li was 1.5mol% and sinterign condition was 1275$^{\circ}C$/4hr, at which we cudl obtain following results ; dielectric constant ($\varepsilon$$_{r}$) of f20.0, quality factor(Qxf$_{0}$) of 78,000 GHz and temperature coefficient of resonant frequency($\tau$$_{f}$) of -1.6 ppm/$^{\circ}C$.>.>.>.

Keywords

References

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