Microwave Dielectric Properties of CaTiO$_3$and CaTiO$_3$-TiO$_2$Ceramics

CaTiO$_3$및 CaTiO$_3$-TiO$_2$세라믹스의 마이크로파 유전특성

  • 홍석경 (한국과학기술원 세라믹스 공정연구실) ;
  • 윤중락 (한국과학기술원 세라믹스 공정연구실) ;
  • 김경용 (한국과학기술원 세라믹스 공정연구실)
  • Published : 1993.08.01


Microwave dielectric properties of CaTiO3 and CaTiO3-TiO2 ceramics for the composition range between 40 and 50 mol% CaO in CaO-TiO2 binary system were investigated. CaTiO3 ceramics with50 mol% CaO showed the dielectric constant (e,) of 178, the temperature coefficient of resonant frequency(c,) of+1000 ppm/'c and the qualify factor Q of 2760 (f0=2.7 GHz ). Dielectric constant and temperature coefficient of resonant frequency of ceramics with dual phases of CaTiO3 and TiO2 decreased gradually from those of CaTiO3 as the CaO content decreased. Q value and density were found to have minimum at the composition of 47 mol% CaO. The degradation of Q value and density in dual phase ceramics seems to be caused by the large pores at grain boundaries and/or within grains remained after rapid growth of CaTiO3 grains as TiO2 Phase decreased.