Effects of an external magnetic field on the perpendicular magnetic anisotropy of electrodeposited micro-patterned arrays

We have investigated effects of an external magnetic field on perpendicular magnetic anisotropy (PMA) of electrodeposited continuous films and micro-patterned arrays. For continuous films, external magnetic field gave rise to a highly aligned grain structure with PMA. Our results indicate that the effect of applied magnetic field is apparent only at specific current density. XRD patterns showed that electrodeposited continuous Co films consist of hexagonal cobalt only and have strong texture for grains with the c-axis lying perpendicular to the film plane. The patterned arrays were fabricated by UV-LIGA process, and PMA was modified by changing the aspect ratio of patterned arrays. Our results suggest that there is a critical aspect ratio at which PMA dominates in-plane anisotropy. For the patterned arrays, however, the external magnetic field was not very effective due to a large concentration polarization.