Thin scandium-containing layers fabricated by different methods are good systems to investigate some properties of Al-Sc intermetallic compounds (IMC). The electrochemical deposition of a thin scandium layer onto a solid metallic surface leads to complex diffusion processes, especially if the second metal forms a number of IMC with Sc. Here, we used the electromotive force (EMF) method to study thin Al-Sc films in dynamics. Also, the Al-Sc alloy layers were prepared by direct aluminium-scandium interaction. The results of SEM and EDX investigations of these alloys are also presented in this paper. Analogue coatings (like Sc on Ni, Y on Cu, Al on Ni etc.) were also considered in order to discuss the phase sequence formation.