RF Integrated Electromagnetic-Noise Filters Incorporated with Nano-granular Co41Fe38Al3O8 Soft Manetic Thin Films on Coplanar Transmission Line

Abstract

The RF integrated noise filters are fabricated by photolithography. The stack for the electromagnetic noise filters consists of the nano-granular (Co41Fe38Al13O8) soft magnetic film2/transmission linelayer (Cu/Ti)2-substrate. A good signal-attenuation feature along with a low signal-reflection feature is observed in the present filters. Especially in the noise filter incorporated with a Co41Fe38Al13O8 magnetic film with lateral dimensions of 2000 mm wide, 15 mm long and 1 mm thick, the maximum magnitude of signal attenuation reaches -55 dB, and the magnitude of signal reflection is below -10 dB in the overall frequency range. And this level of signal attenuation is much larger than that of a noise filter incorporated with a Fe magnetic film.