BA FERRITE FILMS WITH LARGE SATURATION MAGNETIZATION AND HIGH COERCIVITY PREPARED BY LOW-TEMPERATURE SPUTTER-DEPOSITION

Ba ferrite films were deposited in a mixture of Xe, Ar, and O-2 by usi ng facing targets sputtering apparatus with sintered targets of Fe-exc essive BaM ferrite. By using Xe as sputtering gas, the bombardment of energetic Ar atoms recoiled from target to film surface was sufficient ly suppressed and Fe content in Ba ferrite crystallites was significan tly increased. It was found that the segregation of spinel crystallite s among BaM ones were not observed and these BaM crystallites revealed the excellent c-axis orientation normal to film plane and clear perpe ndicular magnetic anisotropy. At substrate temperature T-s of 600 degr ees C, saturation magnetization 4 pi M(s) of 5.1 kG, which is larger t han that of BaM ferrite single crystal, and perpendicular coercivity H -c perpendicular to of 2.4 kOe were obtained. BaM ferrite films compos ed of well c-axis oriented crystallites with large perpendicular magne tic anisotropy constant, large saturation magnetization 4 pi M(s) of 4 .7 kG and high perpendicular coercivity H-c perpendicular to of 2.4 kO e were obtained at substrate temperature T-s as low as 475 degrees C. (C) 1996 American Institute of Physics.