YIG Film for Magnetic Field Sensor

Single crystal $Y_3Fe_5O_{12}$ (YIG) film was grown onto (111) oriented gadolinium gallium garnet (GGG) substrate by the liquid phase epitaxy (PLD) technique. The X-ray diffraction measurements showed that epitaxial growth of the film along its (111) axis. The surface characteristic was investigated by atomic force microscopy (AFM) measurement. The magnetic field sensor consisted of a rectangular shape with 5 mm wide, 15 mm long and 5 μm thick YIG film and a pair of identical 50 μm wide microstrip copper transducers elements separated by 6 mm. The filter was tested by measuring reflection $S_{11}$ characteristic at various bias magnetic fields. The results have showed that when the bias field increased from 0 to 2.5 kOe, the frequency value corresponding to $S_{11}$ maxima increased from 1 GHz to 9 GHz. This suggests that the wide range magnetic field sensing and the highly sensitive field sensing are simultaneously fulfilled with the YIG film.