X-Ray Absorption Spectra and Self-Bias Ferromagnetic Resonance of FeCoB Films Prepared by Composition Gradient Sputtering.

Fe0.7Co0.3B films with a thickness of 100 nm were prepared by composition gradient sputtering on (100) single-crystal Si substrates. A considerable increase in uniaxial magnetic anisotropy fields Hk from 180.6 to 295.5 Oe was achieved by the gradient compositioninduced stress. Although the saturation magnetization 4\pi MS slightly decreases from 16.3 to 13.5 kG with the increase in the B concentration, the ferromagnetic frequency f\mathrm FMR increases from 4.82 to 5.62 GHz due to the domination of Hk . The X-ray absorption spectra revealed that the decrease in the 4\pi MS with B concentration can be attributed to the hybridization between Fe and B atoms. [ABSTRACT FROM AUTHOR]