YIG Thin Film Used to Miniaturize a Coplanar Junction Circulator

Abstract : The preparation of Yttrium Iron Garnet films (YIG) presenting controlled magnetic properties is of great interest for miniaturization of RF passive components. The present work deals with the integration of YIG ferrite sputtered films for coplanar circulators. These components must work at frequencies above 10GHz, and they must be compatible with mass-production and low-cost process. The YIG films (of thickness 15 μm) are deposited on an alumina substrate by RF magnetron sputtering. Their structural mechanical and magnetic properties in the millimetre wave range are optimised to enable the film's integration. A circulator is fabricated using such prepared film, and its properties in the microwave range are characterised using a network analyzer and a probing system.