Tuning τf of Li4Mg2SbO6F microwave dielectric ceramics through Li2SnO3 addition

다국어 초록 (Multilingual Abstract)

Microwave ceramics with low dielectric constant (εr<15), high quality factor (Q×f > 50,000 GHz) and near-zero temperaturecoefficient of resonance frequency (|τf|≤10 ppm/oC) are drawing tremendous attentions for basic study and 5G communication.
To obtain above parameters, the (1-x)Li4Mg2SbO6F–xLi2SnO3 (x=0.65-0.85) composite ceramics were fabricated through a solidstate reaction route at 825-900 oC. X-ray diffraction analysis showed two phase coexistence of cubic structural Li4Mg2SbO6F andmonoclinic structural Li2SnO3. The microwave dielectric properties (MDPs) of Li4Mg2SbO6F-host counterpart is significantlyimproved with an amount of Li2SnO3 addition (x=0.75). For the x=0.75 composition, with increment of sintering temperature,its volume density and dielectric constant (εr) rose little by little, its quality factor (Q×f) rose first and then decreased, and itstemperature coefficient of resonance frequency (τf) remained stable. Optimum MDPs with a εr of 12.9, Q×f of 60, 100 GHzand τf of -10.6 ppm/oC were achieved at x=0.75 composition sintered at 875 oC, this ceramics also exhibited good co-firingchemical compatibility with silver electrode.