The Preparation and Magnetic Properties of Strontium Ferrite Thin Film for High Density Recording

This paper reports on the preparation and magnetic properties of strontium ferrite thin films. All specimen films were deposited by a de magnetron sputtering apparatus. The substrate is thermally oxidized silicon wafer. The effects of substrate temperature (T(s)), oxygen partial pressure and target composition on structure and magnetic properties were investigated. It is found that for T(s) > 400 degreesC the films begin to crystallize and the increase of substrate temperature and oxygen partial pressure are beneficial to improve c-axis orientation normal to the film plane. The saturation magnetization M,increases with the increase of substrate temperature T,and decreases slightly with the increase of oxygen partial pressure. The film prepared by the target composition of SrO . 4Fe(2)O(3) at 600 degreesC has the highest values of M(s) and H(e) in perpendicular direction, they are 321 emu/cm(3) and 3.4 kOe, respectively.