Nanocrystalline Al₂O₃-barrier-coating
on a polymeric substrate, deposited
via ECR-MWCVD

The goal of R&D in this area is to develop a barrier-coatings that decreases/hinders the permeation of H₂O und O₂ into the polymeric substrate (e.g. flexible displays). In this context we are trying to find films that show better performance in combination with lower production costs compared to commercially available solutions.
The barrier-coatings we are looking at are called ultra-barrier-coatings. One requirement of such coatings is that they show a H₂O-permeation of less than 10^-5 g m^-2 day^-1 at 25 °C. It is well-known that the performance of such coatings is governed rather by dislocations than film properties. For that reason multi-layer coatings, based on alternating oxide- and polymer-layers, are a promising approach. An essential requirement in this case is an ultra-smooth polymeric substrate. The best results so far were achieved by using polymeric substrates with an RMS roughness below 1nm, that do not show any spikes.

Contact: Xin Jiang

Hard-chromium layer on a
carbon-fibre-reinfoced-polymer roll

Todays main applications for carbon-fibre-reinforced-polymers (CFRPs) lie in the field of aerospace engineering. The primary characteristics of these composites are a high specific stability and stiffness in combination with a low specific weight. Since 1993 the Chair of Surface- and Materials Technology successfully carries out research in this area in order to improve this advanced composite even further.
One key project deals with the metalization of these CFRPs. In this case the adhesion of the metal film on the CFRP is of uttermost importance for most of the technical applications. Therefore, the goal of our research is to provide a metal-film/CFRP system with supreme film-adhesion.

Contact: Xin Jiang