Abstract
In order to study the origin of perpendicular magnetic anisotropy in Bi-substituted iron garnet thin films, a series of samples with the composition of YBi2Fe5-xGaxO12 (0.36<x<0.97) was prepared by rf sputtering onto several substrates having various thermal expansion coefficients. The stress (σ) was calculated from the difference in thermal expansion between the film and the substrate. The anisotropy constant (Ku) of the films increased linearly with a in the range from σ=-9.0 × 109 erg/cm3 to 3.0 × 109 erg/cm3. Ku decreased linearly with x in the composition range. The experimental results were discussed and compared with the results on Al substituted films.
