Magnetic Recording Characteristics of Co Ferrite Perpendicular Anisotropy Film

Spinel ferrite Co0.10Fe2.90O4 film of thickness 0.21 ¿m was prepared on a glass disk substrate by plasma-assisted MO-CVD using mixed vapor containing Fe(C5H7O2)3, Co(C5H7O2)3 and O2. The film saturation magnetization and coercivity in the direction normal to the film plane at 8 kOe was 210 emu/cc and 1250 Oe respectively. X-ray diffraction patterns and SEM images of the film showed a columnar structure with a ≪100≫ preferred orientation. Magnetic recording tests were performed on the medium in disk form, using a MIG head of gap length 0.25 ¿m, at a relative speed of 9.4 m/s and a flying height of 0.1 ¿m. The recording density D50 was 15 kFRPI, and the reproduced waveform at 2.7 kFRPI had a dipulse shape indicating a perpendicular magnetization component.