On the influence of PDMS (polydimethylsiloxane) substrate surface energy in wrinkling of DLC (diamond-like carbon) thin films

We have explored the influence of surface energy of the PDMS (polydimethylsiloxane) substrate on the wrinkling of diamond-like carbon thin films. The surface energy of PDMS can be tuned by exposure to oxygen plasma or by shallow-implantation of gold. The result is an increase in the wrinkling wavelength and amplitude. By means of a tri-layer wrinkling model, we discuss whether the major contribution to the wavelength variation is via the surface energy of the substrate or via the mechanical properties of the interface layer resulting from the surface treatment. We conclude that the surface energy of the substrate is an important property that must be considered in order to provide a complete description of wrinkling phenomena.