Microwave dielectric properties of SiO2 ceramics with addition of Li2TiO3

Abstract Using a conventional solid-state reaction method SiO 2 ceramics with addition of Li 2 TiO 3 were synthesized and their phase evolution, chemical reactions, microstructure and microwave dielectric properties were studied. The microwave dielectric properties of SiO 2 ceramics with addition of Li 2 TiO 3 strongly depend on the formation and the decomposed of Li 2 (TiO)(SiO 4 ) intermediate phase. The tridymite phase was formed for all samples sintered above 1150 °C and its microwave dielectric properties were reported for the first time ( ϵ r = 2.58, Q × f = 25,800 GHz , τ f = −17.8 ppm/°C). The promising ceramics of 0.945SiO 2 –0.055Li 2 TiO 3 sintered at 1050 °C were found to possess good microwave dielectric properties: ϵ r = 3.21, Q × f = 10,180 GHz and τ f ∼ 0.17 ppm/°C.