Mo AND W DOPPING EFFECTS ON CoCrPt RECORDING THIN FILM MEDIA
Details
In order to optimize the magnetic recording properties for CoCrPt recording thin film media, different Mo and W doping CoCrPt based magnetic thin films were fabricated by using DC magnetron sputtering method. It was observed that Mo and W doping could increase the coercivity(H_c), at the same time maintain lower Pt content. Sole W doping showed no apparent trend of enhancing the coercivity by rising the Mo contents. For samples with less W or Mo doping, the saturation magnetization(M_S)value increased significantly when we tried to further doping. This trend was preserved for different working pressure. But for samples with higher W or Mo contents, M_S is unlikely to change much. It suggested that doping atoms may easily penetrate into Co rich grain core area and help Cr atom reset at the grain boundary. Evidences from X-ray diffraction study showed that lattice constants of Co were varied by more Mo doping. On the other hand, coercive squareness(S^*)studies found that moderate W content doping, may have less exchange coupling.
