The effect of composition on Li2(Mg0.3Zn0.7)Ti3O8–xTiO2 microwave dielectric ceramics for low temperature co-fired ceramics technology application

The effect of composition of Li2(Mg0.3Zn0.7)Ti3O8–xTiO2 (−0.36≤x≤0.36, for short LMZT) on sinterability, crystalline phase, microstructure and microwave dielectric properties of the ZnO–B2O3–SiO2 (for short ZBS) glass doped samples was systematically investigated. It shows that as x is over zero, rutile phase was detected and the crystalline grain size of LMZT ceramics decrease abruptly. It was also found that the bulk density and the quality factor (Q×f) gradually decreased, dielectric constant (εr) increased, the temperature coefficient of resonant frequency (τf) shifted to positive value with the increase of x value. When x=0.12, LMZT ceramics with 3 wt% ZBS sintered at 900 °C for 3 h show excellent dielectric properties: εr=25.1, Q×f=19,620 GHz, τf=−2.3 ppm/°C. It is compatible with Ag electrodes, which makes it a promising ceramic for low temperature co-fired ceramics technology application.

► x in Li2(Mg0.3Zn0.7)Ti3xO8 composition determine the grain growth of dielectrics. ► TiO2 content (x) greatly affects the dielectric properties of dielectrics. ► ZBS can effectively decrease the sintering temperature of dielectrics to 900 °C. ► The dielectrics are capable of co-firing with silver for LTCC application.