2003 Volume 3 Issue 4 Pages 133-136
The RF electromagnetic noise attenuation on coplanar transmission line was investigated using the newly The RF electromagnetic noise attenuation on coplanar transmission line was investigated using the newly developed spin sprayed Ni-Zn(-Co) soft ferrite films with high resistivity. The RF noise suppressor was composed of magnetic film/polyimide/Cu coplanar transmission line/seed layer on glass substrate. The coplanar transmission line with a characteristic impedance of 50 Ω had a 50 μm-wide and 3 μm-thick signal line. The power loss of the coplanar transmission line with Ni-Zn(-Co) ferrites using insulating layer between the transmission line and magnetic film was smaller than that of CoNbZr films at GHz range. It is due to the high resistivity (517×102Ωcm-240×103Ωcm) of the ferrite films in comparison with that of the metallic magnetic CoNbZr film (120 μΩcm). The power loss of the coplanar transmission line using the ferrite films without insulating layer was compared with that of CoNbZr with a 7.5-μm-thick insulating layer. The power loss of the ferrite films without insulating layer was as large as that of the CoNbZr film with insulating layer over 1 GHz.