Effect of the Annealing Time on Micro-Structures and Magnetic Properties of Barium Ferrite Sputtered Films

The effects of the annealing time on barium ferrite (BaM) thin films were studied. After deposition without substrate heating, the films were annealed at 900°C in air. Films annealed for 45 s. or longer were found to crystallize and had a tendency for the c axis to be oriented in a perpendicular direction. Films with high coercivity and high squareness ratio of about 3 kOe and 0.8, respectively, in the perpendicular direction could be prepared in an annealing time of 60 s. The grain size and the roughness of the surface were increased with the annealing time.