MAGNETIC-PROPERTIES OF COBALT FERRITE FILMS WITH PERPENDICULAR MAGNETIC-ANISOTROPY

Cobalt ferrite films with perpendicular magnetic anisotropy were fabri cated by facing targets sputtering and their magnetic properties and r ecording characteristics were studied. When a film was deposited at P- O2 = 0 mTorr and annealed at T-a, = 300 degrees C, a (CoFe2O4)-(Co-CoO ) composite film with perpendicular magnetic anisotropy was formed. Th e composite film, which had H-c perpendicular to, = 1.5 kOe, H-c perpe ndicular to, = 3.5 and Sq(perpendicular to) = 0.46, had magnetic prope rties superior to those in a CoFe2O4 single-phase film. The recording characteristics of the (CoFe2O4)-(Co-CoO) composite film were measured . The reproduced waveform was a dipulse type, indicating that the him had a perpendicular magnetic anisotropy. The value of D-50 was 48.5 kF CI.