Of Cofe <sub> 2 </ Sub> O <sub> 4 </ Sub> Thin Films, Characterization And Magnetic Studies

Cobalt ferrite (CoFe2O4) thin films can be used as high density magnetic recording media because of its high coercivity, saturation magnetization,magnetocrystalline anisotropy, excellent chemical stability and mechanical hardness. CoFe2O4 thin films are being investigated extensively in the perpendicular magnetic recording materials.In this paper, the fabrication process of electrodeposit CoFe2 and micro-structure and magnetic properties of CoFe2O4 thin films which were prepared by electrodeposit oxygenation were systematically studied from experimental aspect,Comparing with micro-structure and magnetic properties of CoFe2O4 thin films which were prepared by RF magnetron sputtering.In the study of the fabrication process of electrodeposition CoFe2,Particular investigate the effect law of concentration of the primary salt, concentration of saccharine,PH,density of electric current on composition of plating layer and speed of sediment.The optimum process of electrodeposition CoFe2 were CoSO4·7H2O of 7.0g/L,FeSO4·7H2O of 7.0g/L, saccharine of 0.8 g/L,PH of 4.0,plating solution temperater of 50℃, electric current density of 10mA/cm2. CoFe2O4 thin films were made by oxygenizing CoFe2 at 500℃. CoFe2O4/Cu/Si(100) films annealed in atmosphere had cubic spinel structure. The magnetic properties of CoFe2O4/Cu/Si(100) films were perpendicular anisotropy, thereinto,Films annealed at 700℃had highest coercivity, its perpendicular and parallel coercivities were 171.6 KAm-1 and 74.8KA KAm-1, The intension of perpendicular saturation magnetic and surplus magnetic perpendicular were 388.2 KAm-1 and 275.3 KAm-1, with perpendicular remanence ratio of 0.62, while films annealed at 900℃had largest perpendicular remanence ratio of 0.78.Preparing CoFe2O4 thin films by RF magnetron sputtering. The conventional annealed CoFe2O4/Cu/Si(100) films had cubic spinel structure , the films have large strain. CoFe2O4/Cu/Si(100) films had high perpendicular anisotropy . Films annealed at 700℃had highest coercivity, its perpendicular and parallel coercivities were 713.5 KAm-1 and 250.3KAm-1, The intension of perpendicular saturation magnetic and surplus magnetic perpendicular were 388.2 KAm-1 and 275.3 KAm-1, with perpendicular remanence ratio of 0.71, And films annealed at 900℃had largest perpendicular remanence ratio of 0.82. All films had high magnetization and remant magnetization.