Substrate-dependent deposition of Cu thin films by molecular dynamics simulations

Abstract

Polyethylene terephthalate (PET)/Cu composite films simultaneously exhibit the merits of flexibility, light weight and excellent electrical conductivity, which have potential application in 5G technology. Despite PET/Cu films were prepared by available experiments, few studies have further provided an atomistic-scale understanding of these deposition processes. Here, growths of Cu thin films on Cu and PET substrates have been carried out by molecular dynamics (MD) simulations and vacuum evaporation experiments. Comparisons of surface roughness, crystal structures and interfacial adhesion for Cu films deposited on these two substrates have been performed in detail. A conclusion has been achieved that Cu films deposited on PET substrate exhibit the lower surface roughness and stronger adhesion than those on metal substrate. This investigation will provide a deep understanding of substrate-dependent deposition performance of metal thin films.