Analytical investigation of the variations of nano-film densities with thickness

In this article, we report an extensive study of mass density variations with increasing thickness of many nanofilms (Al, AlN, Cr, Cu, SiC, SiO₂, Si₃N₄ and ZnO) deposited on several substrates (MgO, quartz and stainless steel). From, the analysis and the results quantification, it was found that the mass-density dependence showed dispersive behaviours: increasing layer thickness leads to an initial increase (or decrease) of the density (according to layer/substrate combination) followed by a saturation region. Moreover, we determined analytical density-thickness relations that could be used to determine the mass density of the nanolayer by just knowing its thickness and the bulk density.