A composition gradient sputtering method was employed to deposit a series of (FexCo1-x)1-yHfy alloy films with different Fe/Co atomic ratios and Hf-doping. At Fe/Co = 70/30, the magnetically annealed (Fe0.7Co0.3)1-yHfy films with y = 0.087 – 0.124 showed a very high uniaxial anisotropy and an ultrahigh ferromagnetic resonance frequency over 7 GHz after the films were annealed at 350 °C, while at Fe/Co = 50/50, the as-deposited (Fe0.5Co0.5)1-yHfy films with y = 0.074 – 0.168 showed an excellent in-plane uniaxial anisotropy and high ferromagnetic resonance frequency over 3 GHz. These Fe-Co-Hf films deposited by the composition gradient sputtering method exhibited ahigh saturation magnetization of 1.8 – 2.2 T, a large uniaxial anisotropy field of 200 – 500 Oe, and a high ferromagnetic resonance frequency over 7 GHz, which provides great opportunities for integrated magnetic devices.

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