Magnetic Properties of Fe-C Films Prepared by Getter Sputtering Method

The magnetic properties and structure of Fe-C system thin films were studied. Values of the intrinsic coercivity MHC increase from 50 ~ 70 Oe at a substrate temperature Tsub = 200°C to their maxima of 250 ~ 310 Oe at Tsub = 350°C. The saturation magnetization Ms varies from 600 to 900 G, reaching a minima in the Tsub range between 300 to 400°C, where the MHC values are maxima. X-ray diffraction analyses show an amorphous structure for the film at Tsub = 150°C, and show several peaks for those at Tsub = 250 ~ 400°C indicating micro-crystals of Fe3C, Fe and C.