10 GHz bandstop microstrip filter using excitation of magnetostatic surface wave in a patterned Ni_(78)Fe_(22) ferromagnetic film

摘要

Various microstrips with a ferromagnetic core were designed and fabricated on a silicon substrate. The core was formed by a 0.5-mu m-thick Ni_(78)Fe_(22) film, patterned into rectangular prisms. Measurement results for attenuation constant versus frequency show a peak value of approx 50 dB/cm around 10 GHz. Electromagnetic simulations show that the attenuation observed is due to the energy exchange between the quasi-TEM mode of the microstrip and magnetostatic surface modes excited in the direction perpendicular to the signal line.