Structure and Magnetic Property of CoFeCr Sputtered Film

The dependence of magnetic properties of CoFeCr films on film composition and the effects of heat treatment are discussed. Saturation magnetization started decreasing when the Cr concentration was increased to 40 at% and reached zero at 58 at%. Ms, Ku and Hc¿ rapidly increased when heat treatment was performed above 300°C in a vacuum chamber on a (Co55Fe45)53Cr47 film. The same phenomenon was exhibited by a Fe45Cr55 film. This result is also similar to that of a CoCr film heat treated in air, which may indicate that heat treatment in a vacuum induces selective oxidation of Cr.