Perovskite Solar Cells with All Functional Layers Deposited by Magnetron Sputtering

Exploring deposition techniques suitable for industrial production is an important development direction for perovskite solar cells (PSCs). Magnetron sputtering is one of the most well-developed vapor deposition techniques in the electronics industry, with advantages such as wide material selection, uniform and dense film formation, and a fast deposition speed. All functional layers of PSCs can be deposited with magnetron sputtering. Replacing the organic charge transport layer (CTL) with a sputtered inorganic CTL can also reduce cost and improve stability. However, due to the working principle of momentum exchange in magnetron sputtering, the deposited particles have an extremely high kinetic energy. It will damage the soft lattice perovskite material if the deposition process is continued upon the perovskite layer. In this work, devices with a structure of FTO/NiOx/perovskite/SnO2/Ag were prepared by magnetron sputtering. A mixed sputtering buffer layer of PMMA and PCBM was coated on top of the perovskite layer to prevent the damage caused by further-deposited SnO2 while ensuring good charge transport. Finally, the power conversion efficiency (PCE) of the PSCs based on solution-deposited perovskite reached 17.43%, and the PCE of PSCs with all functional layers (including perovskite layers) deposited by magnetron sputtering reached 14.62%. Thanks to the dense and stable inorganic CTL, the device exhibited excellent long-term stability, maintaining 93.5% of its initial PCE after being placed in a nitrogen box for 2000 h. This work, for the first time, achieved magnetron sputtering deposition of all functional layers for PSCs. This new fabrication process offers a new path for the industrialization of PSCs.