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Cu/Ni multilayer coatings prepared by RF/DC magnetron sputtering process were characterized using x-ray diffraction (XRD), nanoindentation and atomic force microscopy (AFM) techniques. Films deposited under certain deposition conditions showed the appearance of satellite reflections around the principal reflections in the XRD data, indicating the formation of superlattice structure. Nanohardness measurements were performed on the films prepared under different deposition conditions, e.g. modulation wavelength (Λ), copper to nickel thickness ratio (t_Cu/t_Ni) and substrate temperature (T_s). Nanohardness data revealed that the hardness was enhanced by a factor of ∼2.5 times that of the rule-of-mixtures value. This enhancement in hardness occurred over a limited range of Λ. The results indicated that the hardness also depends on the copper to nickel thickness ratio and for t_Cu/t_Ni≃0.30 the films exhibited a …