Composition Dependence of Structural and Magnetic Properties of Electrodeposited Co-Cu Films

The structural and magnetic properties of Co-Cu films were studied in terms of Co content in the films. The surface morphology of the films showed that the film with the lowest Co content (3 wt. %) had dendritic structures, whereas the surface of the film containing the highest amount of Co (61 wt. %) was more uniform with acicular shapes in some parts. X-ray diffraction patterns of the films showed that their crystal structure is a mixture of dominantly face-centered cubic (fcc) and hexagonal close-packed phases. At the lowest Co content, separate fcc (111) peaks appear, whereas the increase of Co content converts the peaks to be a single broad Co-Cu peak. The vibrating sample magnetometer measurements revealed that the saturation magnetization increases and coercivity decreases due to the decrease of the grain size caused by the increase of the Co content in the film. The structural and magnetic properties of Co-Cu films can be tailored, since these properties are directly related to the ratio of Co to Cu in the film.