Thin-film ferrite materials for microwave and millimeter wave integrated circuits (invited) (abstract)

Abstract

Conventional microwave and millimeter wave systems use ferrites in a variety of components. In general, each application imposes specific requirements on the magnetic properties of the ferrite. In addition, some devices require the ferrite to be in single-crystal form. In order to produce ferrite components that are compatible with microwave and millimeter wave integrated circuits, additional constraints are imposed on the ferrite, especially if fully monolithic integration is required. In general, the ferrites must be prepared in thin film form on substrates that are chosen primarily to meet requirements other than compatibility with the ferrite film. Moreover, as is well known, the magnetic properties of ferrites are quite sensitive to the conditions that exist during their preparation. Thus, ferrites prepared by thin film deposition techniques may have properties different from bulk ferrites. This talk will review progress on methods for preparing polycrystalline ferrite films by techniques such as sputter deposition and laser-assisted deposition and methods for preparing single-crystal ferrite films in forms that may be compatible with epitaxial deposition of compound semiconductors.