Processing and Application of Ceramics (Jun 2010)
Low temperature sintered ZnTiO3 dielectric ceramics with temperature coefficient of dielectric constant near zero
Abstract
ZnTiO3 compound is an attractive dielectric ceramics owing to its interesting dielectric properties in high frequency range (εr= 19, QXf = 30,000GHz, τε ≈ +120 ppm/°C). The structure, microstructure and dielectric properties of sintered ZnTiO3, with a mixture of ZnO-B2O3 glass phase and CuO oxide as sintering aids, have been investigated. For all compounds, the sintering temperature becomes 850°C due to the glass addition. It is also shown that the addition of CuO oxide allows a control of the temperature coefficient of the permittivity (τε). This parameter varies from positive to negative values with increasing the CuO content. The ZnTiO3 composition sintered at 850°C with 5 wt.% ZnO-B2O3 glass phase and 2.2 wt.% CuO addition exhibits attractive dielectric properties (εr = 23, tan δ < 10-3 and a temperature coefficient of the dielectric constant near zero, τε= 3 ppm/°C) at 1 MHz. All these properties lead this system compatible for manufacturing Ag based electrodes multilayer dielectrics devices needed for LTCC application or other multilayer dielectric components.