Abstract
Al-substituted Ba ferrite (Al-BaM) films with a composition of BaAlxFe12-xO19 (Al content x = 0,1,2) were deposited on SiOx/Si wafers with Pt seed layers. A post-annealing process and high substrate temperature Ts are necessary to crystallize the films. With an increase of the Al content x in Al-BaM ferrite films, the saturation magnetization 4πMs decreased, while the perpendicular coercivity Hc⊥ increased, reaching over 3.3 kOe. The perpendicular squareness ratio S⊥ was increased to about 0.9 by substitution of Al for Fe. The Al-BaM ferrite films with suitable Hc⊥ and large S⊥ prepared in this study may be applicable as perpendicular magnetic recording layers with low noise levels.
