Solution-Free Growth of CsPbBr 3 Perovskite Films Using a Fast and Scalable Close Space Sublimation Method

The all-inorganic metal halide perovskite CsPbBr$_3$ is a well-known semiconductor which attracts attention from many researches in the field of optoelectronics. While CsPbBr$_3$ in the form of single crystals offer the best charge transport properties, their high cost of fabrication makes them less suitable for large-scale applications. Polycrystalline films on the other hand, can fill this market and numerous solution and vapor based techniques exist to produce them. However, no superior solution is found yet and we propose the less explored close space sublimation (CSS), a fast and scalable physical vapor deposition technique, as a viable processing technique for manufacturing CsPbBr$_3$ films. We show the fabrication of high quality single phase CsPbBr$_3$ films with homogenous film thicknesses over an area of 3.14 cm². By optimizing the deposition temperature a growth rate of 10 µm/min can be reached with a material utilization up to 98 %. In addition, the necessary CsPbBr$_3$ source material is synthesized via ball milling, hence, the whole process is solvent-free. This work aims at rationalizing the CSS process, offering a comprehensive study of the impact of the deposition conditions on the growth of CsPbBr$_3$.