Low-loss and low-temperature firable Li2Mg3SnO6-Ba3(VO4)2 microwave dielectric ceramics for LTCC applications

Abstract A new low-loss and low-temperature fired (1 − x)Li2Mg3SnO6-xBa3(VO4)2-3 wt% LiF ((1 − x)L2MS-xBV-0.03LiF) ceramic was prepared via a conventional solid-state route. The results indicate that L2MS and BV phases can stably coexist in the composite up to at least 900 °C. The appearance of a secondary phase Li4MgSn2O7 at temperatures lower than 800 °C was ascribed to the low-temperature decomposition of L2MS, irrespective of the existence of BV or LiF. Microwave dielectric properties of L2MS-BV composites generally displayed a nearly linear relation with x and obeyed a well-known mixing rule. With the help of 3 wt% LiF, the x = 0.37 sample sintered only at 850 °C for 6 h exhibited excellent microwave dielectric properties of er = 12.8, Q × f= 101,705 GHz (@ 9.64 GHz) and near-zero τf of −2.9 ppm/°C. The good chemical compatibility with Ag further indicates that the 0.63L2MS – 0.37BV-0.03LiF composite ceramic would be a promising dielectric material for low temperature co-fired ceramic applications.