Fully vacuum-deposited perovskite solar cells in substrate configuration

Summary

A solar cell in the substrate configuration has an opaque back metal electrode on the substrate and a transparent conducting oxide (TCO) electrode at the front of the active stack. This allows the area of the solar cell to be scaled with relative ease, as the incorporation of metal gridlines on the top TCO electrode, which is necessary to counter the resistive losses of the latter, does not influence the processing of the underlying device layers. Here, we demonstrate the fabrication of perovskite solar cells in the substrate configuration using vacuum-deposition methods. The best cells have a power conversion efficiency (PCE) of ∼19%, which is comparable to that of the simultaneously fabricated conventional superstrate cells (PCE ∼19.5%). Moreover, both the substrate and superstrate devices exhibit similar thermal stability at 85°C in N₂ environment, maintaining >80% of their original PCE for more than 550 h.