In this study, in order to evaluate the optimal conditions of a garnet material for a magneto-optic spatial light modulator (MOSLM) application, bismuth substituted yttrium iron (Bi:YIG) films were fabricated by RF magnetron sputtering, and their magnetic, magneto-optic and optical properties were investigated dependent on the annealing temperature. With an increase of the annealing temperature, the magnetic, magneto-optic and optical properties were increased, and their maximum values were shown at 950 degrees C and 850 degrees C, respectively. From X-ray diffraction, energy dispersive X-ray spectroscopy, and atomic force microscope analyses, magnetic and magneto-optic properties were affected by the substitution and evaporation of Bi atoms and the variation of the composition, and the roughness of surface had an effect on the transmittance of Bi:YIG films. As an experimental result, we could think that the optimal annealing temperature is 900 degrees C because the optimal condition for a MOSLM device should be taken into consideration in terms of all variable properties.

Keywords: Bi : YIG film; annealing temperature; RF magnetron sputtering; magnetic properties; transmittance