Deposition of c-axis oriented BaM ferrite layers with low surface roughness on textured underlayers

Ba ferrite layers were deposited on ZnO(001), Au(111), Pt(111), and Pt(100) underlayers using facing target sputtering, and the surface smoothnesses, crystal orientations, and magnetic characteristics were compared. The center-line average roughness R, was smallest at 1.7 nm for a Ba ferrite layer deposited on a Pt(111) underlayer. Ba ferrite layers deposited on underlayers other than Pt(100) exhibited preferential c-axis orientation and their magnetization was mainly oriented perpendicular to the film plane. The smoothest surface, coercivity, as well as high perpendicular and low in-plane coercivity was attained for a Ba ferrite layer deposited on a Pt(111) underlayer.