Cedar Creek at Cedartown, Georgia-- floodflow characteristics at bridge site of Georgia Avenue relocation (supplement to open-file report 75-46)

Coverage and Stability of NHx Terminated Cobalt and Ruthenium Surfaces: a First Principles Investigation

10.26434/chemrxiv.8428217 ◽

2019 ◽

Author(s):

Ji Liu ◽

Michael Nolan

Keyword(s):

Metal Surfaces ◽

High Vacuum ◽

Atomic Layer ◽

Nitrogen Plasma ◽

Operating Conditions ◽

Ultra High Vacuum ◽

Bridge Site ◽

Stable Surface ◽

Saturation Coverage ◽

The Stability

<div>In the atomic layer deposition (ALD) of Cobalt (Co) and Ruthenium (Ru) metal using nitrogen plasma, the structure and composition of the post N-plasma NHx terminated (x = 1 or 2) metal surfaces are not well known but are important in the subsequent metal containing pulse. In this paper, we use the low-index (001) and (100) surfaces of Co and Ru as models of the metal polycrystalline thin films. The (001) surface with a hexagonal surface structure is the most stable surface and the (100) surface with a zigzag structure is the least stable surface but has high reactivity. We investigate the stability of NH and NH2 terminations on these surfaces to determine the saturation coverage of NHx on Co and Ru. NH is most stable in the hollow hcp site on (001) surface and the bridge site on the (100) surface, while NH2 prefers the bridge site on both (001) and (100) surfaces. The differential energy is calculated to find the saturation coverage of NH and NH2. We also present results on mixed NH/NH2-terminations. The results are analyzed by thermodynamics using Gibbs free energies (ΔG) to reveal temperature effects on the stability of NH and NH2 terminations. Ultra-high vacuum (UHV) and standard ALD</div><div>operating conditions are considered. Under typical ALD operating conditions we find that the most stable NHx terminated metal surfaces are 1 ML NH on Ru (001) surface (350K-550K), 5/9 ML NH on Co (001) surface (400K-650K) and a mixture of NH and NH2 on both Ru (100) and Co (100) surfaces.</div>

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ACADEMY Journal 7(9), 2018

10.31219/osf.io/wdt3h ◽

2018 ◽

Author(s):

Liudmila Vyacheslavovna Fomina ◽

Саидова Феруза Бахтияровна

Keyword(s):

Review Process ◽

Final Decision ◽

Research Subjects ◽

Open File ◽

Specific Research ◽

Blind Review

"Journal of the Academy" isan international,peerreviewedmonthly journal. It is dedicated tothe publication of original scientific articles invarious academic disciplines.Articles that may be of interest to a wide rangeof researchers, welcome, and are not limited tothose who work on specific research subjects."Journal of the Academy" has an open file,according to which the published articles areavailable immediately after its publication, withthe exception of the embargo.ExpertiseThe magazine has a blind review process. Allarticles will initially be evaluated by the editor tomatch the magazine. The manuscripts that areconsidered suitable, are usually sent at leasttwo independent experts to evaluate thescientific quality of the article. The editor isresponsible for the final decision on whether toaccept or reject the article. Editor's decision isfinal.

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