Dielectric performance and physical characterization of (Mg0.6Zn0.4)0.95Ni0.05TiO3 ceramics with ATiO3 (A = Ca, Sr) additions for microwave applications

The dielectric performance, physical characterization, and microwave applications of the (1 − x)(Mg0.6Zn0.4)0.95Ni0.05TiO3 − xCaTiO3 or xSrTiO3 fabricated by solid-state reaction method were investigated. The phase composition and microstructure characteristics of these two mixtures were analyzed by XRD, EDS, and SEM to demonstrate two-phase systems. The dielectric performance of the mixed ceramic systems strongly controlled by the quantities of CaTiO3 and SrTiO3 additions and near-zero temperature coefficient of resonant frequency was obtained by appropriate stoichiometry. The mixture of 0.92(Mg0.6Zn0.4)0.95Ni0.05TiO3 − 0.08CaTiO3 ceramic sintered at 1200 °C for 4 h revealed the dielectric constant of 25.0, the quality factor of 49,000 (GHz), and the temperature coefficient of + 5.0 (ppm/°C). For applications in microwave wireless devices such as filters, antennas, and so on, the 0.92(Mg0.6Zn0.4)0.95Ni0.05TiO3 − 0.08CaTiO3 ceramics is proposed as a potential candidate for substrate material. Moreover, we designed and simulated a hairpin band-pass filter using the proposed dielectric mixture to demonstrate the practicality of a wireless communication device.