High coercivity /spl gamma/-(Fe,Co,Mn)/sub 2/O/sub 3/ thin films for magnetic recording

Thin (Fe,Co,Mn)/sub 3/O/sub 4/ films were deposited in-situ on a Si substrate under well controlled O/sub 2/ partial pressure by dc-reactive magnetron sputtering. The coercivity of as-deposited magnetite films is around 400/spl sim/640 Oe. After oxidation at 360/spl deg/C for 90 minutes, the films transform to maghemite /spl gamma/-(Co,Mn,Fe)/sub 2/O/sub 3/ completely, and the coercivity is increased 1/spl sim/7 times to 640/spl sim/3500 Oe, depending on the target composition. The origin of coercivity enhancement is attributed to magneto-anisotropy which is induced by the interfacial stress of the films and the directional order imposed by Co and Mn.