Proceedings of International Conference on Hybrid and Organic Photovoltaics (HOPV23)
DOI: https://doi.org/10.29363/nanoge.hopv.2023.091
Publication date: 30th March 2023
Metal Halide Perovskites (HaP) represent the most promising alternative to further develop the photovoltaic industry due to properties such as low exciton binding energy, high absorptivity, tunable band gap or lightweight. Currently, most of the research in Perovskite Solar Cells (PSCs) relies on solution based synthetic pathways of the photoactive HaP layer lidding to inhomogeneities on rough/ textured surfaces. Thus, fabrication of PSCs via vacuum co-evaporation of the precursor salts (i.e. for MAPbI3 we co-sublime PbI2 and MAI) relies on a reproducible procedure for the co-sublimation of PbI2 and MAI based on an evaporator chamber setup with only two quartz crystal microbalances (QCMs) to control their deposition rates. Furthermore, vacuum co-evaporation for thin-film fabrication has been extensively used in industry enabling Lab-to-Fab transition. Nonetheless, for efficient solar cells, vacuum co-evaporation of MAPbI3 can be time consuming (i.e. the usual deposition rate in our lab is 0.65 Å/s, taking around 2 h for the deposition of a 500 nm thick perovskite. Herein, we show that it is possible to speed up these deposition rates four to six times quicker still achieving solar cells with power conversion efficiencies (PCE) close to 20%. Thus, fabricating HaP layers of more than a micron thick yielding an increase in short circuit current (Jsc, ~ 23 mA/cm2) for HaP with a 1.58 eV bandgap without losing on open circuit voltage (Voc).