Investigation on the effect of tungsten doping and sintering temperature on microwave dielectric properties of lithium magnesium silicate ceramics

Demand for dielectric ceramics has been increasing due to their broad range of applications in microwave communication domains. Lithium Magnesium Silicate (LMS) can be categorized as a dielectric ceramic which owns good dielectric properties suitable for substrates in microwave integrated circuits. Effect of tungsten doping on the structural and dielectric characteristics of LMS is examined in this work. Tungsten-doped LMS ceramic systems were synthesized through conventional solid-state method. Doping effect on crystal structure and microstructure of the samples was analyzed using X-ray diffractograms and field emission scanning electron micrographs. Impact of dopant concentration and sintering temperature on the microstructural densification was investigated. Parallel plate capacitor method using DUT in LCR meter was employed to measure the relative permittivity and dielectric loss values of tungsten-doped LMS ceramics. 10% tungsten-doped LMS (Li₂Mg_0.90W_0.10SiO₄) ceramic was sintered at 1100 ̊C for 4 h and it exhibited a lowest dielectric loss value of 9.65 × 10⁻³ and relative permittivity of 7.22.