Scientists at the Fraunhofer Institute for Solar Energy Systems in Germany have developed a perovskite-silicon tandem solar cell with an efficiency of 19.35% using the mask-and-plate copper metallization technique, showcasing the potential for industrial metallization of next-generation solar cells. The method involves inkjet printing a resist "mask" with narrow openings and electroplating metals like copper to reduce shading and improve efficiency. The use of copper instead of silver lowers material costs and improves resource scalability. Additionally, academics have found that using copper in the metallization process does not harm perovskite-silicon tandem solar cells, with various technologies developed to reduce the use of silver in solar cells. These advancements were presented in a study published in Solar Energy Materials and Solar Cells.