Role of Substrate on the Fractal Characteristics of Nanostructure Surfaces of Electrodeposited Nickel Thin Films

Abstract

This study investigates the structure, morphological, and roughness properties of electrodeposited nickel thin films grown on different substrates, that is, silicon, copper, and gold. X‐ray diffraction analysis reveals that the Ni coatings exhibit a face‐centered‐cubic phase, regardless of the substrate used, although the texture is mainly influenced by the substrate. Atomic force microscopy images show that larger grains are obtained with gold substrates, while smaller ones are observed with copper and silicon substrates, in agreement with scanning electron microscopy. The results demonstrate that both topological and fractal characteristics of the Ni thin films are significantly influenced by the type of substrate. Statistical parameters are quantified to compare the surface morphology of the different samples. Fractal analysis reveals that the fractal dimensions of all surfaces range between 2 and 3, indicating self‐affinity. Fractal succolarity and lacunarity are measured to assess the penetration of a liquid into the surface and the distribution of gaps in the Ni film surfaces, respectively. Minkowski functionals are utilized for topological analysis to characterize the internal structure of the Ni thin films. The observed differences in roughness characteristics provide evidence that the type of substrate affects the nucleation and growth of surface features during electrodeposition.