Diffusion at the Film–Substrate Interface during Nickel Electrocrystallization on a Copper Substrate

The results of experimental studies of the diffusion layer at the interface between a nickel electrolyte film and a copper substrate are presented. Studies have shown that in the transition layer, diffusion of the deposited metal into the substrate material occurs. The depth of the diffusion layer and, consequently, the concentration of interstitial nickel atoms strongly depend on the electrocrystallization conditions: 2 μm in the constant-current mode and 4 μm under laser-assisted deposition. The diffusion coefficient of nickel adatoms in polycrystalline copper is 8.3 × 10^–16 m²/s in the constant-current deposition mode and 3.3 × 10^–13 m²/s under laser-assisted deposition.