Perpendicular Magnetic Anisotropy in Gd-Co Films Prepared by Ion-Beam Sputtering

The increase in perpendicular magnetic anisotropy in RF sputtered Gd-Co films with application of a negative bias voltage is thought to originate in structural changes due to resputtering effects. Dual-ion-beam sputtering was used to form Gd-Co films, and the relation between perpendicular magnetic anisotropy and resputtering was studied. In experiments using both dual-ion-beam sputtering and a single ion gun, K
u
decreased monotonically with increasing Gd concentration. Hence increases in perpendicular anisotropy can be explained directly by decreases in Gd concentration together with the Gd content dependence of the perpendicular anisotropy.