The main goal of current research being conducted in the field of solar energy is to increase solar cell efficiency while at the same time reducing costs as far as possible ‒ decreasing the amount of material needed is already a very promising starting point.

In cooperation with its industrial partners Christian Koenen GmbH, ICB GmbH and Murakami Co. Ltd, the Fraunhofer Institute for Solar Energy Systems ISE has now managed to accomplish this balancing act. Thanks to innovative technologies for the fine-line metallization of solar cells, contact fingers with a width of merely 19µm and a height of 18µm could be produced in a single printing step. This means that 30 per cent less silver is needed, which in turn leads to a significant reduction in manufacturing costs. The ultra-thin contact fingers will also contribute to improvements in module performance: an efficiency of 22.1% has already been achieved in tests using contact fingers with a width of 24µm.

The newly developed fine-line screen printing metallization behind this comes from the collaborative project FINALE, which was funded by the Federal Ministry for Economic Affairs and Energy (BMWi) from the end of 2016 to spring 2019. The project focused on improving the front-side metallization process through innovative screen and paste systems. In the near future, these will enable the industrial production of highly efficient solar modules. Their contact fingers, which are about 30% narrower than today’s industrial standard, will contribute to a significant increase in performance, as was the case in the successful tests carried out at Fraunhofer ISE.