The growing need for increasingly miniaturized devices has placed high importance and demands on nanofabrication technologies with high-quality, low temperatures, and low-cost techniques. In the past few years, the development and recent advances in atomic layer deposition (ALD) processes boosted interest in their use in advanced electronic and nano/microelectromechanical systems (NEMS/MEMS) device manufacturing. In this context, non-thermal plasma (NTP) technology has been highlighted because it allowed the ALD technique to expand its process window and the fabrication of several nanomaterials at reduced temperatures, allowing thermosensitive substrates to be covered with good formability and uniformity. In this review article, we comprehensively describe how the NTP changed the ALD universe and expanded it in device fabrication for different applications. We also present an overview of the efforts and developed strategies to gather the NTP and ALD technologies with the consecutive formation of plasma-assisted ALD (PA-ALD) technique, which has been successfully applied in nanofabrication and surface modification. The advantages and limitations currently faced by this technique are presented and discussed. We conclude this review by showing the atomic layer etching (ALE) technique, another development of NTP and ALD junction that has gained more and more attention by allowing significant advancements in plasma-assisted nanofabrication.

The study of the structural stability of carbonates under different pressure and temperature conditions is important for modeling the carbon budget in the Earth's interior and the stability of carbonation products of carbon capture and storage (CCS) solutions. In this work, we confirm the existence of the two dense polymorphs of the hydrated magnesium carbonate MgCO₃·3H₂O nesquehonite mineral previously reported, and we characterize their structures using synchrotron single-crystal X-ray diffraction at 3.1 and 11.6 GPa. Phase transitions entail the distortion and atomic rearrangement of the Mg-centered polyhedra and the tilting of the [CO₃] carbonate units. In particular, the Mg coordination number increases from 6 in nesquehonite to 7 in the second high-pressure phase, while maintaining a topology based on complex MgCO₃(H₂O)₂ chains. We also studied their vibrational behavior upon compression using Raman spectroscopy and complemented the experimental results with density-functional theory (DFT) calculations. The role played by hydrogen bonds in the compressibility and the polymorphism of this hydrated carbonate is also discussed.

This review summarizes the synthesis, structure, stability, and hydrogen bonding of MgCO ₃ ·3H ₂ O nesquehonite, highlighting experimental and theoretical insights into its properties, phase behavior, and potential applications.

In the presented study, a novel approach for thermal atomic layer deposition (ALD) of Al₂O₃ thin films using plasma-activated water (PAW) as a co-reactant, replacing traditionally employed deionized (DI) water, is introduced. Utilizing ex situ PAW achieves up to a 16.4% increase in the growth per cycle (GPC) of Al₂O₃ films, consistent with results from plasma-enhanced atomic layer deposition (PEALD). Time-resolved mass spectrometry (TRMS) revealed disparities in CH₄ partial pressures between TMA reactions with DI water and PAW, with PAW demonstrating enhanced reactivity. Reactive oxygen species (ROS), namely H₂O₂ and O₃, are posited to activate Si(100) substrate sites, thereby improving GPC and film quality. Specifically, Al₂O₃ films grown with PAW pH = 3.1 displayed optimal stoichiometry, reduced carbon content, and an expanded bandgap. This study thus establishes “PAW-ALD” as a descriptor for this ALD variation and highlights the significance of comprehensive assessments of PAW in ALD processes.

Understanding the structural stability of hydrated carbonates and bicarbonates under different thermodynamic conditions is crucial, as they play an important role in the carbon cycle, in environmental chemistry, and geochemistry. Sodium sesquicarbonate dihydrate, Na₃H(CO₃)₂·2H₂O trona, is a naturally occurring evaporite mineral also found in magmatic environments. In this work, we carried out high-pressure (HP) in situ synchrotron powder and single-crystal X-ray diffraction (XRD) measurements on a naturally occurring trona specimen. A high-pressure monoclinic to triclinic phase transition occurred at 12.8 GPa, and the structure of the dense HP trona phase was solved. The coordination number of sodium atoms increased from 6 in the low-pressure polymorph to 7-8 in the HP one. Additionally, our results did not show any indication of the phase transition previously reported at 7 GPa based on Raman spectroscopy. The compressibility and anisotropy of low- and high-pressure phases were determined. Birch-Murnaghan equation of state parameters were fitted to the pressure-volume data sets, yielding a bulk modulus of 35(2) GPa (K' = 4.4(9)) for trona using neon as pressure-transmitting medium. Density functional theory calculations supported the experimental results, confirming the structural stability of the phases obtained by XRD.

The Ca–Mg double carbonate huntite, Mg₃Ca(CO₃)₄, undergoes a second-order phase transition upon quasi-hydrostatic compression (21 GPa) that entails a progressive change in the coordination number of the Ca atoms, from 6 to 9.