Magnetic tuning of partially magnetized ferrite based microwave notch filter

This paper present synthesis and fabrication of zinc doped cobalt ferrite thin film (ZCFO), spur-line based microwave notch filter and tuning of this microwave filter in the presence of magnetic bias field. The centre frequency of the fabricated notch filter was 12.77 GHz and 5.4 % tuning is achieved by varying the magnetic field from 0 to 36 kA/m. This tuning is based on the change in the permeability value of the ferrite thin film, and the experimental results are confirmed by a commercially available software tool. The complete geometry is used in the flip-chip mode.