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/spl times/15 mm/spl times/1, 2 /spl mu/m)/2-/spl mu/m-thick polyimide/15.2-mm-long and 3-/spl mu/m-thick Cu transmission line/seed layer (Ti/Cu)/1 mm-thick glass substrate. The coplanar transmission lines were prepared by electroplated Cu with 50 /spl Omega/-characteristic impedance. The width of the signal line was 50 /spl mu/m. 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 1-/spl mu/m-thick CoNbZr film, and from -15 to - 57 dB for the 2-/spl mu/m-thick CoPdAlO film, respectively.