Optimization of MOF film deposition process and oxide µ-patterning via Atmospheric Pressure SALD/SMLD

Metal-organic frameworks (MOFs) are an interesting class of self-assembled hybrid materials that are gaining more and more interest in several fields thanks to the tunable porosity and bandgap, mechanical and chemical stability, and low dielectric constant. MOF thin films are particularly interesting for applications such as microelectronics, gas sensing and filtration, photovoltaics, and catalysis. However, these applications are not always compatible with the wet-based chemistries typically used. Therefore, gas-based approaches such as CVD and ALD/MLD represent valid solutions. Nevertheless, Atmospheric Pressure Spatial Molecular layer deposition (AP-SMLD) could represent a faster and easier approach for the direct growth of MOF thin films, but it must be optimized yet. Under this perspective, this study investigated the influence of the substrate and organic ligand bubbling temperatures, the scanning speed, and the influence of water during deposition and post-deposition treatments for the SMLD deposition of Zn(4-(5)-methylimidazole)2 films. The study on this material had to be interrupted midway for safety reasons concerning the 4-(5)-methylimidazole, which was then substituted with the 2-ethylimidazole. The development of a Spatial Atomic Layer Deposition (SALD) nozzle new proof of concept also started for the localised deposition of micrometric MOF patterns.