RF integrated noise suppressor using soft magnetic films

RF integrated noise suppressors were fabricated by integration of soft magnetic films on coplanar transmission lines. The vertical structure of suppressor was composed of the magnetic film (2 mm x 15 mm x 1, 2 mum)/2-mum-thick polyimide/15.2-mm-long and 3-mum-thick Cu transmission line/seed layer (Ti/Cu)/1 mm-thick glass substrate. The coplanar transmission lines were prepared by electroplated Cu with 50 Omega-characteristic impedance. The width of the signal line was 50 mum. The magnetic films, e.g., CoPdAlO and CoNbZr films were deposited by rf magnetron sputtering. Compared with those of the nonintegrated noise suppressor, the magnitude of signal attenuation at resonance point of integrated noise suppressor greatly increased from -4 to -30 dB for the I-mum-thick CoNbZr film, and from -15 to -57 dB for the 2-mum-thick CoPdAlO film, respectively.