Alf (Structured Aluminium Metallisation Firing of Innovative PERC/PERCT Solar Cells)

  • Funding institution: German Federal Ministry for Economic Affairs and Energy (BMWi), Central Innovation Programme for Small and Medium-Sized Enterprises (ZIM)
  • Support code : KF2818605GM4
  • Duration: 01/2015 to 03/2016
  • Consortium: ISC Konstanz and RCT Solutions


The goal of project Alf is to develop a solar cell that is more cost-effective than the usual solar cells on the market (€/Wp). We want to achieve this by developing an aluminium metallisation firing paste, thereby simplifying the production process considerably and making it more stable, as laser structuring is no longer required. At the same time, we will optimise the passivation layer on the back, both in terms of its passivation properties and suitability for metallisation firing. 


An mc PERC cell with diffused back (PERCT) developed by RCT Solutions will serve as the basis for the development of aluminium metallisation firing paste, as the cost of PERCT solar cells can be reduced even further by streamlining the process sequence and making savings on the metallisation paste.

The project partners’ tasks are to be distributed as follows:

RCT Solutions will modify the passivation layer on the back of the solar cell and use an innovative layer stack based on the existing systems technology in order to improve metallisation firing behaviour and the formation of a BSF (Back Surface Field). This will factor in the effect on the solar cell’s performance in the module.

ISC Konstanz will test aluminium pastes available on the market in terms of their suitability for the metallisation of PERCT cells. This will define the baseline for the performance increase of internal developments. Subsequently, our own metallisation pastes will be optimised and analysed for a better understanding of the critical parameters for selecting materials/pastes. This will allow us to carry out a targeted search for the best pastes. Finally, the developed cells will be used in combination with the developed pastes to produce modules and their durability investigated in climate chamber tests.