Single-Source Thermal Ablation of halide perovskites, limitations and opportunities: The lesson of MAPbBr3

Single-Source Thermal Ablation (SSTA) is a vacuum-based evaporation method that was only minorly employed in the preparation of hybrid perovskite materials for solar cells despite some promising early achievements. We study the preparation of MAPbBr3 films, showing that this material does not allow the reproducible preparation of thin films suitable for integration in multijunction devices due to the low adhesion of MABr to the substrate, on one hand, and to the proximity of decomposition and melting temperatures of MAPbBr3 combined with the high vapor pressure of MABr on the other. Based on the insights obtained on MAPbBr3 processing we demonstrate that, conversely, homogeneous fully-inorganic CsPbI2Br thin films can be prepared by SSTA with a stability comparable to that reported for films obtained by spin coating. This work provides guidelines for the selection of halide perovskites that can be successfully prepared by SSTA for thin film application.