Novel temperature stable and low-fired Li2Mg3SnO6-Ca0.9Sr0.1TiO3 composite ceramics

New temperature stable 4 wt% LiF-doped (1-x)Li2Mg3SnO6-xCa0.9Sr0.1TiO3 (LMS-CST, x = 0.20, 0.23, 0.26, 0.29) composite ceramics were fabricated by solid-state reaction for low-temperature co-fired ceramics (LTCC) applications. Sintering temperatures of LMT-CST ceramics were successfully lowered to 925 °C due to LiF liquid-phase sintering. A near zero of τf value was obtained by tuning CST composition. 0.74LMS-0.26CST-4wt% LiF ceramics displayed well-densified microstructures with a relative density of 96.5% and excellent microwave dielectric properties of εr = 17.5, Q × f = 21250 GHz, τf = −5 ppm/°C at 925 °C. The good chemical compatible with Ag electrodes further promises that such samples were suitable for developing LTCC applications in wireless communication systems.