Low Temperature Sintering and Electromagnetic Properties of Z-type Hexagonal Ferrites

Abstract

Higher frequency adaptability has been required for electronic devices. It is well known that Z-type hexagonal ferrites can be used at higher frequency range compared by spinel-type ferrites. Then we applied hexagonal ferrites to multilayer chip inductors with Ag electrodes. Bi₂O₃ and CuO were added in order to lower the firing temperature. Bi₂O₃ segregated at grain boundaries and CuO mainly existed inside grains that was confirmed by TEM-EDX observation. The 1608 chip-inductors were made with the low firing temperature Z-type ferrites and they showed the XR cross point of 1.4 GHz.