The improvement of high-frequency magnetic properties in oriented hcp-Co78Ir22 soft magnetic films fabricated at high substrate temperature

The c-axis oriented hcp-Co78Ir22 soft magnetic thin films with in-plane uniaxial anisotropy and negative magnetocrystalline anisotropy were fabricated with substrate temperature at 30 °C and 500 °C, respectively. Our results further reveal that sputtering under 500 °C can obtain a film with better grain structure and higher degree of orientation, which in turn improves the Ms and the magnetocrystalline anisotropy field. As the Ms and the total out-of-plane anisotropy field including the demagnetization field and the magnetocrystalline anisotropy field were enhanced, the high-frequency magnetic parameter (μi−1)fr is approximately two times larger than that of the sample fabricated at 30 °C. In addition, the damping constant decreases quite a lot with increasing temperature. This work indicates that the high frequency properties can be well adjusted by changing substrate temperature.