Nanogranular (FeCoTiO/SiO2)n Multilayered Films for Noise Suppressor

Magnetic nanogranular FeCoTiO films have been deposited by radio frequency magnetron cosputtering. By simply adjusting the thickness of films, the imaginary permeability spectrum of FeCoTiO films changed from a single ferromagnetic resonance peak to double resonance peaks. Based on this phenomenon, multilayered [FeCoTiO/SiO
₂
(50 nm)]
_n
films with various thickness of FeCoTiO layer were deposited and the characteristics of the electromagnetic noise suppression have been evaluated using an integrated coplanar waveguide transmission line. The multilayered film shows a decoupled M-H curve and a very wide resonance peak with the full-width at half-maximum of 2.6 GHz. The absorption attenuation amplitude reaches to -8 dB at the resonance frequency, and is better than -6 dB for the frequency above 3 GHz.