Researchers at The Hong Kong University of Science and Technology (HKUST) have developed a multi-source co-evaporation recipe that markedly enhances the crystal quality of vacuum-deposited perovskite films. This advance brings all vacuum-deposited single-junction perovskite cells as well as perovskite-on-silicon tandem solar cells closer to scalable production. The research has been reported in Nature Materials, in a paper titled "Crystal-facet-directed all-vacuum-deposited perovskite solar cells."