High frequency permeability of CoFeV thin films deposited on thin flexible substrates

Summary form only given. A growing interest is dedicated to ferromagnetic thin films with high permeability levels up to several GHz. The development of inductors integrated on Si with high Q factor requires thin films with significant permeability levels and very small losses up to GHz frequencies. On the other hand, the development of integrated radio frequency shielding requires materials with high losses, preferably under a suitable form to make flexible Electro-Magnetic Interference suppressors. CoFeV thin films have been sputtered on 7.5/spl mu/m thick kapton sheets using DC magnetron sputtering onto continuously transported flexible medium. The permeability has been measured from 100 MHz up to 18 GHz. The permeability shows that the material exhibits high losses over a very large frequency band. As the material exhibits some coercivity, it has been established that the microwave response of saturated and unsaturated material differ.