Improvement in sintering behavior and microwave dielectric properties in CaMgGe2O6 via zn substitution

A series of CaMgGe 2 O 6 ceramics doped with Zn 2+ ions were designed and fabricated using the solid-state reaction method. The impact of cation doping on sintering behavior, crystal structure, microstructure, and dielectric properties was systematically investigated. Incorporating Zn 2+ ions into the crystal structure optimized the sintering process to enhance densification. Analysis of the crystal structure revealed slight changes in lattice parameters and unit cell volume upon introduction of Zn 2+ dopants, indicating successful incorporation without significant alteration to the overall structure. Microstructural characterization revealed that increasing Zn 2+ content resulted in a finer microstructure with a more uniform grain size distribution. Furthermore, substitution of Zn 2+ effectively reduced dielectric loss in CaMgGe 2 O 6 ceramics while maintaining a stable dielectric constant, making them suitable for high-frequency applications. Among all compositions tested, CaMg 0.8 Zn 0.2 Ge 2 O 6 exhibited exceptional performance with a Q × f value reaching 64,980 GHz along with an ε r of 7.88 and τ f of -36.9 ppm/°C.