Enhanced Microwave Magnetic and Dielectric Properties of YBiIG Ferrite by Ca-Zr Co-substitution

Yttrium iron garnet (Y₃Fe₅O₁₂, YIG) ferrite has excellent magnetic properties that are suitable for microwave communication devices. In the present research, Ca-Zr co-substituted Y_1.83−xBi_1.17Ca_xFe_5−xZr_xO₁₂ (YBiIG, x = 0.00–0.15 with a step of 0.05) ferrites were prepared by a solid-state reaction method to enhance microwave magnetic and dielectric properties. The phase formation, microstructure, and magnetic and dielectric properties of the materials were investigated by x-ray diffraction, scanning electron microscopy, impedance analyzer, vibrating sample magnetometer (VSM), and ferromagnetic resonance (FMR) linewidth. The results showed that Ca²⁺-Zr⁴⁺ ions did not change the phase formation of the ferrites and enhanced the magnetic permeability \(\mu^{{\prime }}\) ${\mu }^{\prime }$ ( \(\mu^{{\prime }}\) ${\mu }^{\prime }$  = 24.10 at 10 MHz, x = 0.15) and dielectric constant ( \(\varepsilon^{{\prime }}\) ${\epsilon }^{\prime }$  = 24.55 at 10 MHz, x = 0.15). Meanwhile, the specific saturation magnetization (σ_s) increased from 20.26 emu/g to 22.79 emu/g with the increase of Ca-Zr substitution, and the FMR linewidth (ΔH) decreased from 406.34 Oe to 339.60 Oe. The work showed that the high dielectric constant exhibited by Ca-Zr-substituted YBiIG ferrite materials has potential application value in high-frequency microwave device applications, such as circulators, isolators, phase shifters, and other microwave components.