Low temperature vacuum annealing study of (Co/Pd)n magnetic multilayers

The correlation between the magnetic properties and the microstructural and chemical composition modifications of Co/Pd magnetic multilayers upon annealing in ultrahigh vacuum at 250 degrees C is presented. Magnetic characterization using magnetic sample magnetometer shows the vertical magnetic anisotropy increase and the switching field distribution decrease in the annealed samples. The larger values of magnetic anisotropy in the annealed samples are further shown using the magnetic force microscopy of the ac demagnetized states in the Co/Pd multilayer films. X-ray diffraction rocking curves show an improvement in the texture and the initial magnetization curve slopes indicate the decreases in defect densities. Overall, vacuum annealing under optimal conditions improves the magnetic properties of Co/Pd multilayers for applications in ultrahigh density magnetic recording. (C) 2008 American Institute of Physics.