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Molecular layer deposition (MLD) is an incredibly powerful and flexible tool for designing completely new materials with novel and unique properties. The low temperature layer‐by‐layer approach and the use of highly reactive reactants allows one to combine vastly different organic and inorganic species and construct nanostructures with subnanometer precision. If not limited by the volatility of the reactants involved, the possibilities will be endless. This is most notable for the organic building blocks where an overall low volatility severely limits the toolbox of large molecules with interesting optical and electrical properties such as red‐ox activity and optical conversion. In this work, different strategies for molecular design of large molecules are investigated that allow vaporization while still having the necessary reactivity for MLD growth. Using these strategies, film growth with perylene and porphyrin derivatives, both molecules well known for their functional and optical properties are successfully achieved. With this knowledge, there is an opening to include much larger and more complex organic molecules into the world of vapor phase chemistry. [ABSTRACT FROM AUTHOR]

Organic-inorganic hybrid materials are of great demand not at least for their enormous application potential in flexible devices. Atomic or molecular layer deposition (ALD or MLD) and vapor phase infiltration (VPI) offer novel pathways for the fabrication of such hybrids, but a clear understanding of the chemistry between the vaporized precursors and functional molecules is still lacking. In this work, the interactions between trimethylaluminum (TMA) and the organic functional groups OH, NH2, and NO2 in the respective substituted phenyls, as well as their stability upon exposure to air are investigated. The experimental evidence agrees with theoretically predicted reaction pathways, showing that TMA initially binds to Lewis basic atoms of the investigated functional groups. Depending on the reaction energy barriers, the interaction between TMA and the investigated functional groups may result in either stable chemical bonding or intermediates that decompose upon exposure to humidity. This investigation contributes to the understanding of ALD/MLD and VPI processes at a molecular level and will support a better process optimization. [ABSTRACT FROM AUTHOR]

Tailored organic thin films with designated molecular arrangements are expected to provide a variety of photonic/electronic devices due to their ability to optimize the performance or to generate new functions by controlling the electron wavefunction shapes. Molecular Layer Deposition (MLD), which enables monomolecular-step organic film growth, is one of the promising fabrication processes of tailored organic thin films. In the present report, first, the concept and an experimental demonstration of MLD are described. Next, after three featured capabilities of MLD, namely, ultra-thin/conformal, tailored, and selective organic film growth are presented, applications of MLD based on these capabilities are reviewed, emphasizing polymer multiple quantum dots we have developed. Finally, conceptual proposal of MLD for the molecular targeted drug delivery for cancer therapy is suggested. [ABSTRACT FROM AUTHOR]

The article describes the usage of molecular layer deposition (MLD) for the conformal coating of ultra-thin aluminum alkoxide (alucone) polymer films on primary silica and titania nanoparticles within a fluidized bed reactor. The usage of in situ mass spectrometry to demonstrate the self-limiting nature of alucone MLD film growth as a function of the individual exposures of trimethylaluminum and ethylene glycol is noted. Also noted is the fact that the highest growth rate was found to coincide with the lowest sample temperature.