X-ray photoelectron spectroscopy study of magnetic films

. Ta/NiO x /Ni 81 Fe 19 /Ta films were prepared by rf reactive and dc magnetron sputtering. The exchange coupling field H ex and the coercivity H c of NiO x /Ni 81 Fe 19 as a function of the ratio of Ar to O 2 during the deposition process were studied. The composition and the chemical states in the interface region of NiO x /NiFe were also investigated using X-ray photoelectron spectroscopy (XPS) and the peak decomposition technique. The results show that the ratio of Ar to O 2 has a great effect on the chemical states of nickel in NiO x films. The exchange coupling field H ex and the coercivity H c of Ta/NiO x /Ni 81 Fe 19 /Ta are thus seriously affected. XPS is shown to be a powerful tool for characterizing magnetic films.