Control of Magnetic Properties of Electroless Co Alloy Perpendicular Magnetic Anisotropy Films by Catalyzing Process

Electroless plated Co alloy films for perpendicular magnetic recording media were investigated as a means of controlling magnetic properties by changing the catalyzing process. In thin regions, such as 500 Å thick, a large difference in magnetic properties was evident for films deposited after acid treatment and those prepared with no acid treatment. This was due to the difference in microstructure of the films. In particular, highly crystallized areas appeared in grains deposited after acid treatment. The films deposited after acid treatment had a high perpendicular coercivity Hc ¿. This high coercivity turned out to be due to these highly crystallized areas. Grain sizes could be controlled through the acid treatment, which changed the density of active nuclei.