Characterization of NixZn1−xFe2O4 and Permittivity of Solid Material of NiO, ZnO, Fe2O3, and NixZn1−xFe2O4 at Microwave Frequency Using Open Ended Coaxial Probe

This paper describes a detailed study on the application of an open ended coaxial probe technique to determine the permittivity of in the frequency range between 1 GHz and 10 GHz. The compositions of the spinel ferrite were 0.1, 0.3, 0.5, 0.7, and 0.9. The samples were prepared by 10-hour sintering at 900°C with 4°C/min increment from room temperature. Particles showed phase purity and crystallinity in powder X-ray diffraction (XRD) analysis. Surface morphology measurement of scanning electron microscopy (SEM) was conducted on the plane surfaces of the molded samples which gave information about grain morphology, boundaries, and porosity. The tabulated grain size for all samples was in the range of 62 nm–175 nm. The complex permittivity of Ni-Zn ferrite samples was determined using the Agilent Dielectric Probe Kit 85070B. The probe assumed the samples were nonmagnetic homogeneous materials. The permittivity values also provide insights into the effect of the fractional composition of on the bulk permittivity values . Vector Network Analyzer 8720B (VNA) was connected via coaxial cable to the Agilent Dielectric Probe Kit 85070B.