Growth and topology of Co–Fe and Co–Ni alloy electrodeposits studied by atomic force microscopy

We show that surface roughness, σ, of the Co-based alloy electrodeposits is affected by their deposition rate, v. σ can be minimised for a particular v value for which there is a change of the filmsʹ preferred growth orientation. This occurs with practically the same surface diffusion length Ds of the ad-atoms with Co–Ni. A more marked deviation of Ds is observed with Co–Fe. The two materials exhibit a self-affine fractal surface pattern, which concurs with the conservative growth mode for Co–Ni, while Co–Fe leads to the KPZ nonconservative process.