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Heterogeneous nanostructures composed of metastable tetragonal 1T-MoS 2 and stable hexagonal 2H-MoS 2 phases are highly promising for a wide range of applications, including catalysis and ion batteries, due to the high electrical conductivity and catalytic activity of the 1T phase. However, a controllable synthesis of stabilized 1T-MoS 2 films over the wafer-scale area is challenging. In this work, a metal-organic chemical vapor deposition process allowing us to obtain ultrathin MoS 2 films containing both 1T and 2H phases and control their ratio through rhenium doping was suggested. As a result, Mo 1- x Re x S 2 films with a 1T-MoS 2 fraction up to ≈30% were obtained, which were relatively stable under normal conditions for a long time. X-ray photoelectron spectroscopy and Raman spectroscopy also indicated that the 1T-MoS 2 phase fraction increased with rhenium concentration increase saturating at Re concentrations above 5 at. %. Also, its concentration was found to significantly affect the film resistivity. Thus, the resistivity of the film containing approximately 30% of the 1T phase was about 130 times lower than that of the film without the 1T phase., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

The influence of the bottom TiO 2 interfacial layer grown by atomic layer deposition on the ferroelectric properties of the TiN/Hf 0.5 Zr 0.5 O 2 /TiN capacitors is systematically investigated. We show that the integration of the TiO 2 layer leads to an increase in the polar orthorhombic phase content in the Hf 0.5 Zr 0.5 O 2 film. In addition, the crystalline structure of the Hf 0.5 Zr 0.5 O 2 film is highly dependent on the thickness of the TiO 2 inset, with monoclinic phase stabilization after the increase of TiO 2 thickness. Special attention in this work is given to the key reliability parameters-retention and endurance. We demonstrate that the integration of the TiO 2 inset induces valuable retention improvement. Using a novel approach to the depolarization measurements, we show that the depolarization contribution to the retention loss is insignificant, which leaves the imprint effect as the root of the retention loss in TiN/TiO 2 /Hf 0.5 Zr 0.5 O 2 /TiN devices. We believe that the integration of the insulator interfacial layer suppresses the scavenging effect from the bottom TiN electrode, leading to a decrease in the oxygen vacancy content in the Hf 0.5 Zr 0.5 O 2 film, which is the main reason for imprint mitigation. At the same time, although the observed retention improvement is very promising for the upcoming technological integration, the field cycling testing revealed the endurance limitations linked to the phase transitions in the TiO 2 layer and the rise of the effective electric field applied to the Hf 0.5 Zr 0.5 O 2 film., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Ultrathin WS 2 films are promising functional materials for electronic and optoelectronic devices. Therefore, their synthesis over a large area, allowing control over their thickness and structure, is an essential task. In this work, we investigated the influence of atomic layer deposition (ALD)-grown WO 3 seed-film thickness on the structural and electrical properties of WS 2 nanosheets obtained via a sulfurization technique. Transmission electron microscopy indicated that the thinnest (1.9 nm) film contains rather big (up to 50 nm) WS 2 grains in the amorphous matrix. The signs of incomplete sulfurization, namely, oxysulfide phase presence, were found by X-ray photoemission spectroscopy analysis. The increase in the seed-film thickness of up to 4.7 nm resulted in a visible grain size decrease down to 15-20 nm, which was accompanied by defect suppression. The observed structural evolution affected the film resistivity, which was found to decrease from ∼10 6 to 10 3 (μΩ·cm) within the investigated thickness range. These results show that the thickness of the ALD-grown seed layer may strongly affect the resultant WS 2 structure and properties. Most valuably, it was shown that the growth of the thinnest WS 2 film (3-4 monolayers) is most challenging due to the amorphous intergrain phase formation, and further investigations focused on preventing the intergrain phase formation should be conducted., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)