Design, Manufacturing and characterization of integrated inductors with magnetic layers for DC-DC converter

Abstract : This paper presents the conception, fabrication and characterization of integrated inductors containing magnetic layers. A novel approach has been used to perform planar magnetic devices by using commercial ferrite substrate. In this paper Yttrium Iron Garnet is used as magnetic material due to the frequency range of the fabricated inductors (up to some hundred MHz). For other application frequency ranges this approach is suitable, only the magnetic material has to be changed. We require different steps of microtechnologies: preparation of glass and ferrite substrates, RF sputtering, photolithography, etching and finally electroplating techniques for copper and gold films. The geometrical magnitudes are determined by using HFSS simulator software. The measurements performed at low and high frequencies (up to 1 GHz) permit to verify the correlation between experiment and simulation results. The inductance of the manufactured spiral inductor is about 200 nH and it is constant from low frequency up to 0.9 GHz.