Dr. Klaus Noller and Dr. Sabine Amberg-Schwab will be honored with Joseph von Fraunhofer Prizes for developing a specially coated barrier film for protecting inorganic solar cells.
A barrier layer or film is required to shield thin-film solar cell from water vapor and oxygen and to enhance the cell’s lifetime.
Dr. Klaus Noller, scientist at the Fraunhofer Institute for Process Engineering and Packaging IVV in Freising, explained the benefits of plastic films. The flexibility and low weight of the material allow for new manufacturing processes that result in reducing the expenses of photovoltaic module production. Thus, printing of solar cells can be done on a plastic film and can be covered with a barrier film.
Dr. Sabine Amberg-Schwab, researcher at the Fraunhofer Institute for Silicate Research ISC in Würzburg, has been working with her team for several years to develop a coating material based on ORMOCER polymers. These polymers can be deployed as an efficient barrier against water vapor and oxygen. The resultant barrier lacquer was integrated with another barrier material such as silicon dioxide. Such combination produced excellent results and the barrier effect was better than adding two layers.
The Würzburg researchers have developed an ORMOCER-based coating material that can be cured and processed easily. The damp testing has shown that the cured lacquer coating needs to be maintained at 85% humidity and 85°C. Hence, the major challenge for the researchers is to develop a process to apply the barrier layers on the film in a perfect and economical way. This obstacle was overcome with the help of a roll-to-roll process. Under the process, the application of the ORMOCER coating has to be done in a dust-free environment.