Fabrication of perovskite solar cells using sputter-processed CH₃NH₃PbI₃ films

Perovskite/crystalline silicon tandem structures have attracted much attention as promising high-efficiency solar cells. To achieve higher efficiencies, a method of depositing perovskite films on textured substrates is required. In this work, we established the process of fabricating perovskite films by sputtering. Sputter-processed perovskite films showed characteristics similar to those of their solution-processed counterparts. In addition, a power conversion efficiency of 1.84% was attained from solar cells employing sputter-processed films. Moreover, it was confirmed that homogeneous films can be obtained even on substrates with significant roughness. Our results indicate that sputtering is a promising method of achieving high-efficiency tandem cells.