Crystalline quality control in sequential vapor deposited perovskite film toward high efficiency and large scale solar cells

Pure vapor method shows particular advantages in preparing large-area uniform and conformal perovskite film, which can be applied to manufacture perovskite modules and fully textured perovskite/silicon tandem solar cells (TSCs). Here, we provide details on controlling the vapor-solid reaction to acquire high-quality perovskite films, including precisely adjusting vapor pressure and organic salts component, vapor-solid reaction, and post-annealing perovskite film. By employing the optimized conditions, we obtained high-quality perovskite films. Power conversion efficiency (PCE) of the inverted structure device can reach as high as 18.1% with an absorber bandgap of 1.62 eV, among the highest PCE using the vapor technique ( Table S1 ). Significantly, the large-area perovskite film has uniform crystallinity and coverage on textured silicon . Thus, the pure vapor fabrication method of perovskite films shed light on the application of perovskite solar cells because of the potential in module and tandem solar cells.