Ca-Sn co-substituted BiIn-YIG ferrite with narrow FMR linewidth for microwave device application

Abstract

The requirements for improving the performance and miniaturizing microwave devices have led to higher demands for the yttrium iron garnet (YIG) ferrite materials. To achieve YIG ferrite materials with narrow ferromagnetic resonance (FMR) linewidths, and stable magnetic and dielectric properties, Ca-Sn co-substituted YIG samples with the composition Bi0.4Y2.6-xCaxFe4.65-xIn0.35SnxO12 were synthesized via solid-state sintering at 1230 °C. The microstructural, magnetic, and dielectric properties of the samples were systematically tested and analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), impedance analyzer, vibrating sample magnetometry (VSM), and ferromagnetic resonance (FMR). The results indicate that the co-substitution of Ca2+ and Sn4+ ions did not alter the crystal structure of YIG ferrites, and effectively improved the microstructure and performance of the material. When the doping concentration (x) was 0.40, the obtained sample exhibited the narrowest FMR linewidth (ΔH = 43.46 Oe) and excellent magnetic and dielectric properties (4πMs = 1555.68 G, ε′ = 14.12 @ 100 MHz). The material proposed in this study demonstrates significant potential for applications in microwave devices.