Structural properties of coatings prepared by flash evaporation and magnetron sputtering of Cu-15% Sn and Cu-20% Sn alloys

Abstract

The structure of CuSn coatings formed by two methods—flash evaporation and magnetron sputtering—is investigated by SEM and X-ray structural analysis. The effect of the deposition temperature (470–1020 K) on the phase composition, crystallites orientation and distribution of structural components along the thickness of the layer is studied. It is established that coatings obtained by evaporation of Cu-15.2 wt% Sn and Cu-20.2 wt% Sn or by sputtering of a Cu-20.2 wt% Sn target are composed of α-solid solution of Sn in Cu and δ-Cu 31Sn 8 phase, while single phase layers of α-solid solution are formed by sputtering of Cu-15.2 wt% Sn target. The increase of the substrate temperature favours the concentration of the eutectoid component (α + δ) in the surface layer, the effect being strongly enhanced when a ‘vapour-liquid’ condensation mechanism is involved.