T-Type Equivalent Circuit of On-Chip Microstrip Line With Magnetic Film-Type Noise Suppressor

This paper discusses R, L, G, and C parameters of an on-chip transmission line with a magnetic film for developing the design rule of a film-type electromagnetic noise suppressor. A microstrip line (MSL) is fabricated using a regular silicon process, and a Co₈₅Zr₃Nb₁₂(Co-Zr-Nb) film is deposited on the MSL. The target frequency of the noise suppression and the passband are set to 5 GHz and a several hundred MHz range, respectively. The T-type equivalent circuit model is converted from the measured S-parameter. In the passband frequency range, the resistance value of the MSL with the magnetic film is almost the same as that without the film. The measured resistance successfully peaks at 34 Ω around the 5.4 GHz target frequency based on the ferromagnetic resonance and Joule losses. Furthermore, the inductance and the capacitance with the magnetic film are 1.3 and 2.5 times higher, respectively, than without the film because of the high permeability and metallic boundary of the magnetic film. Therefore, these results demonstrate the great usefulness of the approach for developing a standardized design method for a magnetic film-type noise suppressor.