Soft magnetic applications in the RF range

Abstract

Soft magnetic thin-film applications in the RF range are systematically described based on the complex permeability profile of the films. This work demonstrates the metallic thin-film permeability measurements up to 6 GHz under the existence of traveling electric field, two types of ferromagnetic RF integrated inductor with the best properties of L=7.9 nH and Q=12.7 at 2 GHz for a 200×400 μm size four-turn rectangular spiral, and a high frequency carrier type thin-film magnetic field sensor (or so-called GMI sensor) with the AC field sensitivity of 4.8× 10 − 6 A m − 1 / Hz (6× 10 − 12 T/ Hz ) .