| The purpose of this paper is to prepare a new high frequencydielectric ceramic that has high permittivity, low dielectric loss, and lowtemperature coefficient of capacitance. Ba(Zn1/3Nb2/3)O3-CaTiO3 systemis studied in this paper. As one of the cubic perovskite structured ceramics,Ba(Zn1/3Nb2/3)O3 has a higher permittivity, ε41, and a positivetemperature coefficient of capacitance, αC+30×10-6/℃. And CaTiO3also has cube perovskite structure the same as Ba(Zn1/3Nb2/3)O3, it hasvery high permittivity, e=150160, but it has very large negativetemperature coefficient of capacitance αC, -2300×10-6/℃. So theycan form one solid solution, which has a high permittivity about 100, anda low temperature coefficient of capacitance, near 0×10-6/ ℃ .Firstly, this paper studied craftwork of this system. Based on thedielectric performance and microstructure of the system, the best propersintering temperature and the best proper calcination temperature are asfollows:sintering temperature : 1395℃ (ascending 5h, holding 4 h)calcination temperature : 1360℃ (ascending 4.5h, holding 4 h)On the other hand, the composition of CaTiO3, ZrO2 and MnCO3 arealso studied in this paper. The best suit composition is 0.328BaCO3+0.105 ZnO+0.105 Nb2O5+0.013 ZrO2+0.449 CaTiO3.XRD indicated that the main crystal phases of the system areBa(Zn1/3Nb2/3)O3 and CaTiO3. The dielectric properties of the system areas follows:ε=99.97 (measurement frequency 1MHz)tanδ=0.54×10-4 (measurement frequency 1MHz)αC = -13.05×10-6/℃ (+25℃～+85℃,measurement frequency 1kHz)...
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