Atomic layer deposition (ALD) is a sequential thin film deposition technique which allows for high uniformity and thickness control. Although ALD is limited to inorganic precursors, molecular layer deposition (MLD) allows for the use of organic precursors and can be used in conjunction with ALD to result in high-quality hybrid organic—inorganic films. Organic—inorganic perovskite materials for solar cell applications are typically solution processed; this technique is undesirable when compared to vapor processes due to the use of toxic solvents which require careful control of the atmosphere, making it difficult to manufacture. This research focuses on the design of a process for depositing hybrid organic—inorganic perovskite films through a combined ALD/MLD process. There are currently no processes for depositing perovskite materials by ALD/MLD aside from hybrid ALD/solution processing techniques which involve the deposition of lead iodide by ALD and conversion to perovskite by spin coating. Since sequential deposition methods allow for precise thickness control, it would be possible to deposit both 3-D methylammonium lead iodide (MAPbI<sub>3</sub>) and 2-D perovskites. 2-D perovskites have shown the potential to be effective surface passivators for perovskite solar cells. As passivation layers, 2-D perovskites improve long-term stability, decrease interfacial defects and charge recombination, and increase efficiency by enhanced charge extraction from the bulk perovskite.

ALD/MLD of 2-D perovskite passivation layers

ACS Fall 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.