Reaction mechanisms of chlorine reduction on hydroxylated alumina in titanium nitride growth: First principles study

Choi, Woojin; Lee, Sung‐Woo; Han, Donghoon; Lim, Hong Taek; Park, Hwanyeol; Lee, Gun-Do

doi:10.1016/j.apsusc.2021.149391

Cited by 8 publications

(4 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The chemical reactivity of oxide or nitride surfaces can be strongly affected by the presence and coverage of OH (hydroxyl) or NH (amino) groups on the surfaces [35][36][37][38][39][40][41]. At process-relevant temperatures (ca.…”

Section: Resultsmentioning

confidence: 99%

Fluorination of TiN, TiO2, and SiO2 Surfaces by HF toward Selective Atomic Layer Etching (ALE)

Jung

Shong

2023

Coatings

View full text Add to dashboard Cite

As semiconductor devices become miniaturized, the importance of the molecular-level understanding of the fabrication processes is growing. Titanium nitride (TiN) is an important material utilized in various architectural components of semiconductor devices requiring precise control over size and shape. A reported process for atomic layer etching (ALE) of TiN involves surface oxidation into titanium oxide (TiO2) and selective oxidized layer removal by hydrogen fluoride (HF). However, the chemical selectivity of these Ti-based materials in the etching process by HF remains unclear. In this study, computational chemistry methods utilizing density functional theory (DFT) calculations were applied to the fluorination reactions of TiN, TiO2, and SiO2 to identify and compare the surface chemical reactivity of these substrates toward etching processes. It is shown that the materials can be etched using HF, leaving TiF4 and SiF4 as the byproducts. However, while such a TiN reaction is thermodynamically hindered, the etching of TiO2 and SiO2 is suggested to be favorable. Our study provides theoretical insights into the fluorination reactivity of TiN, which has not been reported previously regardless of technological importance. Furthermore, we explore the etching selectivity between TiN, TiO2, and SiO2, which is a crucial factor in the ALE process conditions of TiN.

show abstract

Section: Resultsmentioning

confidence: 99%

Fluorination of TiN, TiO2, and SiO2 Surfaces by HF toward Selective Atomic Layer Etching (ALE)

Jung

Shong

2023

Coatings

View full text Add to dashboard Cite

show abstract

“…In addition, density functional theory (DFT) was also attracting widespread interest in materials research, [29] which was a powerful tool for studying the structure, [30] interaction mechanisms [31] and electronic properties. [32][33][34][35] Shirazi et al [36,37] reported the Atomic ALD of MoS 2 by DFT, which the Mo-(NMe 2 ) 2 (N t Bu) 2 was the precursor and the H 2 S was the coreagent on Si(0001) surface.…”

Section: Introductionmentioning

confidence: 99%

The Mechanism of Growing MoS₂ via Sulfuration of Molybdenum Hexacarbonyl: First principles study

Yang

Wang

et al. 2023

ChemistrySelect

View full text Add to dashboard Cite

Transition metal dichalcogenides (TMDC s ) films are potential two-dimensional materials for next-generation optoelectronic and electronic devices. Chemical Vapor Deposition, Atomic Layer Deposition, and Metal-Organic Chemical Vapor Deposition are usually used for the synthesis of the MoS 2 films by taking Mo(CO) 6 as precursors. However, the mechanism of adsorption and reaction of Mo(CO) 6 on the substrate at the molecular level are hardly to know only by the experiments. In this study, the detailed reactions of Mo(CO) 6 on α-Al 2 O 3 (0001) are investigated by density functional theory to demonstrate the growth mechanism of MoS 2. It is found that, Mo(CO) 6 could form a stable chemical bond with the Al-1 site on the surface, which has large adsorption energy and charge transfer. The decomposition of Mo(CO) 6 into Mo(CO) 3 exists in a clear order, with the top carbonyl composing firstly, follow by the two parallel carbonyls. In order to determine the stable model of Mo(CO) 3 , adsorption energy and DOS are analyzed. The E ad is À 5.65 eV and the 4d5 s orbitals of Mo atom overlap with the 2 s2p orbitals of O atom, indicating the new chemical bond is forming in 3O-Al-2 model. Finally, the LST/QST (Linear Synchronous Transit/Quadratic Synchronous Transit) method is used to search for transition states of Mo(CO) 3 sulfuration reactions with CH 3 S 2 CH 3 , H 2 S, and S 2 respectively. This paper provides a theoretical basis for the experimental preparation of MoS 2 and provides research ideas for the general synthesis of TMDCs.

show abstract

“…The challenge presented by using a high voltage to speed up program/erase functions in memory devices creates a need for crystalline phases that can improve the conductivity of the metal gate in memory structures. Tungsten films are commonly used as metal gates due to their relatively high conductivity compared with other candidate metallic materials, which improves the performance of memory devices. , …”

Section: Introductionmentioning

confidence: 99%

“…Tungsten films are commonly used as metal gates due to their relatively high conductivity compared with other candidate metallic materials, which improves the performance of memory devices. 8,9 Growing tungsten films using atomic layer deposition (ALD) is the most successful process among elemental metal ALD processes. ALD-W uses the well-known tungsten precursor, WF 6 , and a reducing agent of borane or a silane compound.…”

Section: Introductionmentioning

confidence: 99%

First-Principles Investigation of Morphological Evolution of Tungsten Growth on Alumina Surfaces: Implications for Thin-Film Growth

Park

Han

Lim

et al. 2022

ACS Appl. Nano Mater.

Self Cite

View full text Add to dashboard Cite

The fundamentals and interfacial interaction mechanism of tungsten-alumina heterostructures are not yet fully understood. Here, we present a first-principles investigation of the thermodynamic driving force responsible for the phase transition from amorphous to crystalline in the growth of a tungsten thin film on an alumina substrate. Density functional theory and ab initio molecular dynamics collectively provide a first-principles explanation of how amorphous tungsten films become thermodynamically favorable at finite nanoscales (0.7 nm). The growth of cubic tungsten films is energetically inhibited until the thickness exceeds 0.7 nm. An amorphous tungsten layer would therefore sustain conformal coverage below such a thickness. The approach described here can be applied to computational discovery and design of corrosion-resistant materials, alloys, and semiconductors, providing an ab initio framework to search for methods of optimizing both conductivity and interfacial adhesion. Other possible applications include the synthesis of energy-storage materials, solid-state batteries, and thin-film growth of semiconductor materials, particularly for the prediction of pathways for choosing polymorphs during growth.

show abstract

Reaction mechanisms of chlorine reduction on hydroxylated alumina in titanium nitride growth: First principles study

Cited by 8 publications

References 32 publications

Fluorination of TiN, TiO2, and SiO2 Surfaces by HF toward Selective Atomic Layer Etching (ALE)

Fluorination of TiN, TiO2, and SiO2 Surfaces by HF toward Selective Atomic Layer Etching (ALE)

The Mechanism of Growing MoS₂ via Sulfuration of Molybdenum Hexacarbonyl: First principles study

First-Principles Investigation of Morphological Evolution of Tungsten Growth on Alumina Surfaces: Implications for Thin-Film Growth

Contact Info

Product

Resources

About

Reaction mechanisms of chlorine reduction on hydroxylated alumina in titanium nitride growth: First principles study

Cited by 8 publications

References 32 publications

Fluorination of TiN, TiO2, and SiO2 Surfaces by HF toward Selective Atomic Layer Etching (ALE)

Fluorination of TiN, TiO2, and SiO2 Surfaces by HF toward Selective Atomic Layer Etching (ALE)

The Mechanism of Growing MoS2 via Sulfuration of Molybdenum Hexacarbonyl: First principles study

First-Principles Investigation of Morphological Evolution of Tungsten Growth on Alumina Surfaces: Implications for Thin-Film Growth

Contact Info

Product

Resources

About

The Mechanism of Growing MoS₂ via Sulfuration of Molybdenum Hexacarbonyl: First principles study