Contents I. Introduction
Magnetic components such as inductors and transformers are well used in high frequencies for filters, oscillators and in the field of power electronics (for DC-DC converters…). Most of these components are discrete and the trend to reduce cost and volume is to integrate low power components by using new approaches [1] [2]. Several papers are devoted to the study of such components. Among these approaches, some authors [3]–[5] prefer the use of magnetic layers in order to improve their characteristics and to decrease the volume. Indeed the use of magnetic core or magnetic layers allows to multiply by the inductance or to strongly decrease the size of these components. Moreover the use of magnetic material reduces the electromagnetic radiations that are provided by inductive devices. Many types of magnetic materials are used such as ferromagnetic, amorphous but ferrites are interesting materials for applications that range from tens of kHz up to some hundreds of MHz. They exhibit high resistivity (the resistivity depends on the frequency range) to limit Eddy current losses and an interesting permeability. With all ferrites it is possible to use the same approach to design, fabricate, model and characterize inductors for a lot of different applications. The same process can be used to fabricate low frequency devices and high frequency components; only the ferrite material has to be changed. The studies that are currently carried out in our laboratory concern all these aspects: from the design until the characterization of micro-fabricated devices.
