Investigation of Li2Zn3Ti4O12-based temperature stable dielectric ceramics for LTCC applications

Abstract

A low temperature co-fired ceramic (LTCC) was fabricated at 910 °C /2 h from the powder mixture of Li2Zn3Ti4O12, TiO2 and a B2O3–La2O3–MgO–TiO2 glass (BLMT), and the influence of TiO2 on microstructure and dielectric properties of the composite was investigated in the composition range (wt%) of 20BLMT–(80 − x)Li2Zn3Ti4O12–xTiO2 (x = 0, 2.5, 5, 7.5, 9 and 10). The results showed that all samples consisted of Li2Zn3Ti4O12, TiO2, LaBO3 and LaMgB5O10 phase. And LaBO3, LaMgB5O10 and a small amounts of TiO2 were crystallized from BLMT glass during sintering process. As x increases, dielectric constant and temperature coefficient of resonance frequency of the composites demonstrated gradually increase, whereas the quality factor of the sample of x = 0 wt% was about 41,500 GHz and the ones maintained stable at a high level of 49,000–51,000 GHz for other samples. The composite with x = 9 wt% had an optimal microwave dielectric properties with the dielectric constant of 20.2, quality factor of 50,000 GHz and temperature coefficient of resonant frequency of − 0.33 ppm/°C.