Characterizations of low-temperature sintered BaCo1.3Ti1.3Fe9.4O19 M-type ferrite for high-frequency antenna application

Abstract

BaCo1.3Ti1.3Fe9.4O19 ferrite was synthesized by solid-state reaction route. Co and Ti ions were substituted for Fe cation to modify the anisotropy field of the ferrite. The effects of B2O3 and CuO sintering additives on the phase stability, sintering behavior at 900 °C, microstructure development, magnetic and dielectric properties of the ferrite were investigated. The densification of the ferrite at 900 °C was found to increase upon B2O3 and CuO addition. A permittivity of 19 and initial permeability of 11 was obtained in the ferrite containing 5 wt% B2O3 sintering additive. There was a nominal decrease in saturation magnetization of the ferrite with increasing sintering additive. An antenna based on the low temperature sintered ferrite substrate was designed. Antenna parameters such as resonance frequency, return loss, voltage standing wave ratio (VSWR), and bandwidth were simulated and reported. The antenna miniaturization factor (n) was calculated and found n = 11 for the sample with 5 wt% B2O3. The sample containing 3 wt% B2O3 plus 2 wt% CuO showed an impedance of about Zi = 1.