F-1325 Planar Inductors with Ferrite Layers for DC-DC Converter

Abstract

Planar inductors with ferrite layers were fabricated by means of screen printing, photo-lithograpy and electroplating. Screen printing method enable to obtain the coil spacing filled with ferrite. In this structure, since the perpendicular leakage magnetic flux is preferentially passed through the coil spacing and avoids the copper coil position, it is expected to decrease the eddy-current loss. Trial samples of planar inductor with ferrite layers achieved high quality factor of 40 to 70 at 5 MHz.