Film growth phenomena in high-energetic room temperature pulsed laser deposition on polymer surfaces

Coating of plastics by inorganic metal-based films requires profound knowledge about the phenomena occurring in connecting materials of very high and very low (visco-)elastic properties. Buckling and delamination are unwanted, stress-release induced effects leading to severe failure. To overcome the problem of delamination, higher energetic deposition conditions for strengthening the polymer surface by ion implantation are seen as a chance, but bear the risk of high film stresses and, thus, an increase of buckling. To understand these phenomena in pulsed laser deposition (PLD) the current work focuses on topographical, morphological and chemical investigations of polymers coated with thin interface films between 5 and 100 nm thickness. Applying this approach in the room temperature PLD (RT-PLD) enables the understanding of ion implantation during interface growth. The results reveal a strong chemical binding between implanted atoms and polymer chains as well as a hardening of the soft polymer surface, which increases the load capacity. Only very low changes of the surface topography after coating by wrinkling phenomena reveal scarce influence of the ion bombardment and high adhesion of the films.