Ferromagnetic resonance study on Fe–ZnO inhomogeneous magnetic semiconductors

Fe–ZnO inhomogeneous magnetic semiconductor films were synthesized by alternately sputtering very thin Fe layers and ZnO layers under thermal non-equilibrium conditions. The obtained films are in the amorphous state and show large saturation magnetization at room temperature. The angular dependence of the ferromagnetic resonance field for the samples with different compositions was studied. As the Fe content increases, the saturation magnetization increases, and the resonance field in normal resonance mode increases. The linewidth of the ferromagnetic resonance reduces as the Fe content increases, indicating that the inhomogeneity in chemical composition reduces with increasing Fe content. Suitably increasing Fe content is favorable to obtain magnetic semiconductor films with high saturation magnetization at room temperature.