Sputtered Ag thin films with modified morphologies: Influence on wetting property

Graphical abstract: - Highlights: • Ag thin films are deposited by DC magnetron sputtering on Si and W/Si layers. • The influence of the W underlayer morphology on Ag film growth is evidenced. • Variation of the Ag growth mode and roughness is investigated by SEM and AFM. • Wetting property is correlated to the roughness of Ag deposits on Si and W layers. - Abstract: Silver thin films with thickness ranging from 3 nm to 33 nm were sputter deposited onto silicon wafers and tungsten layers. Those W layers were previously synthesized in the same DC magnetron sputter deposition system with various experimental conditions (argon pressure, target to substrate distance) in order to stabilize different surface morphologies. SEM observations and AFM images showed that the growth mode of Ag films is similar on Si substrates and on the smoothest W layers, whereas it is modified for rough W layers made of sharp grains. The effect of the W layer morphology on Ag film growth was clearly evidenced when the deposition took place at high temperature. It is seen that performing the deposition onto substrates of various morphologies allows tailoring the wetting property of the Ag deposit