Synthesis and microwave dielectric studies of pure Li2MgSiO4 and B2O3, MgF2, WO3 added Li2MgSiO4 for substrate applications

Abstract

Synthesis of pure Li2MgSiO4 (LMS) ceramics through solid-state ceramic route and variations in its microwave dielectric properties by addition of different compounds are discussed. Boron trioxide (B2O3), Magnesium Fluoride (MgF2), and Tungsten trioxide (WO3) were used as additives to produce three different ceramics besides pure LMS. Scanning electron microscope and X-ray diffraction spectrometer were used to study the morphology and crystal structure of prepared samples. The densities of the respective samples were measured via Archimedes method. The microwave dielectric properties of the ceramic materials were determined by the cavity perturbation technique using a Scalar Network Analyzer. Pure LMS sintered at 1100 °C/6 h exhibited a relative permittivity (εr) of 5.73 and dielectric loss of 5.897 × 10−4 at 8 GHz. Among the three additives, WO3 improved the relative density of pure LMS from 90.6% to 94.5% and the LMS-WO3 sample sintered at 1100 °C/4 h showed comparatively good dielectric properties, εr = 6.03, tan δ = 6.598 × 10−4 at 8 GHz.