Low-loss microwave dielectrics using rock salt oxide Li ₂MgTiO₄

Rock-salt-structured Li₂MgTiO₄ ceramic was prepared by the conventional mixed oxide route and its microwave dielectric properties were investigated. The microstructures of the ceramics were characterized by SEM. The dielectric properties of the ceramics exhibited a significant dependence on the sintering condition and crystal structure. A new microwave dielectric material, Li₂MgTiO₄ sintered at 1360 °C has a dielectric constant (ε_r) of ̃17.25, a Q × f of ̃97,300 GHz (where f = 9.86 GHz, is the resonant frequency) and a τ_f of ̃-27.2 ppm/°C. The microwave dielectric properties of the ceramic are reported for the first time.