Deposition potential dependence of composition, microstructure, and surface morphology of electrodeposited Ni-Cu alloy films

Composition, microstructure, and surface morphology of Ni-Cu alloy films electrodeposited at different deposition potentials have been investigated. The microstructural analysis carried out by using X-ray diffraction (XRD) confirmed that all Ni-Cu films are polycrystalline in nature and possess face-centered cubic structure. XRD analysis also revealed that the (111) peak of the Ni-Cu alloy films splits into two as Cu-rich and Ni-rich peaks and the peak intensities change depending on the deposition potential and hence the film composition. Compositional analysis of Ni-Cu films carried out by energy dispersive X-ray spectroscopy showed that Ni content within the films increases as the deposition potential becomes more negative. The morphological analysis performed by using a scanning electron microscopy and an atomic force microscopy revealed that the surface morphology changes significantly with applied deposition potential. Furthermore, a direct correlation is observed between the surface roughness and lattice strain.