Fabrication of multilayer chip inductors using Ni–Cu–Zn ferrites

Ni–Cu–Zn ferrite nanopowders were synthesized by co-precipitation method using microwave–hydrothermal (M-H) reaction system. The ferrite formation conditions such as pH, temperature and time were determined in detail according to the reaction conditions. The phase identification, crystallinity and morphology of the prepared samples were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Nanocrystalline ferrites with high surface area were synthesized at temperatures as low as 165 °C in a short time (30 min). The nanoferrite powders were sintered at different sintering temperatures from 800 to 950 °C for 6 h using conventional sintering method. The performance of the sintered Ni–Cu–Zn ferrites has been estimated from the studies of dependence of permeability spectra on the frequency and temperature. Multilayer chip inductors were fabricated from the ferrite using the screen-printing method. Inductance and quality factor of the prepared inductors were measured over a wide frequency range.