Thickness Mediated Morphology Evolution in Sub-10-nm Metal Film Deposition: Implications for Nondestructive Testing

Thickness in sub-10-nm metal film deposition is a seldom explored parameter that can influence not only the mechanical properties but also surface functional characteristics. In this study, we designed bilayer systems comprising Au on poly(dimethylsiloxane) (PDMS) substrate to reveal unique thickness-mediated morphology evaluation phenomenon. Our results show that, within specific range of elastic modulus selected PDMS substrate, wrinkling starts when deposited theoretical thickness around 0.2 nm, reaches maximum deformation at 1–2 and disappears equal or larger than 8 nm. The off suggest strongly impact patterns observed soft elastomers. This finding indicates what may be intrinsic rather thickness-controlled wrinkling. Using 2 nm as highly sensitive nondestructive testing method, potential application for identifying defects solid surfaces proposed.