Center for Functional Nanomaterials Seminar

Surface modification provides a large flexibility regarding to materials with unique features through the manipulation of materials chemistry and structure as well as through the combination of base material properties with surface attributes. It offers the opportunity to tailor the desired properties to a defined application. One of the most important and applied techniques to modify the surface structure and chemistry in nanoscale level is plasma technique.

In this talk I focus on the development of novel DLC-systems with high wear and friction resistance. Hydrogen content and carbon hybridization in DLC coatings can significantly affect both their mechanical and tribological properties. A high contribution of sp3 hybridization is associated with high hardness and low wear performance. Furthermore, this effect is enhanced by increasing bias voltage during coating deposition.

The second example is on bio-inspired coatings. Inspired by nature, like mussels, bone and wood or natural surfaces of animals (dung beetle, ground beetle and mole cricket), man-made materials with well-defined chemistry and topology have been intensively investigated. It was found, that a multilayer design with more homogenous and thicker ceramic layers has the highest hardness and lowest wear coefficients as well as the lowest compressive stress in the ceramic layers, while the adhesion of structured multilayers is superior to smoothed surfaces. This bio-inspired approach can be used to construct a range of multilayer coatings for the advanced engineering.

The last example is a novel approach to achieve controlled etching of extremely thin layers – plasma enhanced atomic layer etching (PEALE). The innovation is based on the fact that about 0.3 nm of unmodified material can be eroded using a special procedure. At this time, controlled etching is achieved by deposition of a thin reactive layer that is removed during an erosion step. This reactive layer is produced by supplying p