MoS2−xOx solid solutions in thin films produced by rf-sputter-deposition

The chemical composition and structure of MoS2 solid lubricant films are intimately related to their friction and wear characteristics. We have conducted an x-ray photoelectron spectroscopy (XPS) study of 1-μm thick radio frequency (rf)-sputter-deposited MoS2 films to determine the chemical state of the films, focusing on the role of oxygen impurities. Concentrations of chemisorbed and bulk species were determined from the Mo 3d, S 2p, and O 1s peak shapes and intensities after annealing the films to temperatures from 425 to 975 K. Films deposited on substrates that were at ∼345 K [ambient temperature (AT) films] and on substrates heated to ∼525 K [high temperature (HT) films] both had ∼10% oxygen within the bulk of the films. The relative areas and shapes of the XPS peaks for the HT films at all annealing temperatures were consistent with the formation of a MoS2−xOx solid solution, where O atoms were probably substituted into S sites in the 2H–MoS2 crystal lattice. In AT films, this phase composition was stable only for annealing temperatures ≥725 K, in agreement with previous studies of the changes in crystal structure of AT films with annealing. The results are discussed in terms of previous studies of the structure and composition of sputter-deposited MoS2 films.

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Ruthenium Sputter Deposition on Organosilicate Glass and on Paralyne: an XPS Study of Interfacial Chemistry, Nucleation and Growth

MRS Proceedings ◽

10.1557/proc-812-f2.5 ◽

2004 ◽

Vol 812 ◽

Cited By ~ 6

Author(s):

X. Zhao ◽

N.P. Magtoto ◽

J. A. Kelber

Keyword(s):

Photoelectron Spectroscopy ◽

Copper Film ◽

Test Results ◽

Interfacial Chemistry ◽

Organosilicate Glass ◽

State Present ◽

Sputter Deposited ◽

Xps Study ◽

Sample Transfer

AbstractThe interactions of sputter-deposited ruthenium with organosilicate glass (OSG) at 300 K have been studied by x-ray photoelectron spectroscopy (XPS) for Ru coverages from ∼ 0.1 monolayer to several monolayers, using in-situ sample transfer between the deposition and analysis chambers. The results indicate Stranski-Krastanov (SK) type growth, with the completion of the first layer of Ru at an average thickness corresponding to 1 monolayer average coverage. Ru(0) is the only electronic state present. XPS core level spectra indicate weak chemical interactions between Ru and the substrate. A less pronounced tendency towards SK growth was observed for Ru deposition on parylene. Deposition of Ru on OSG followed by electroless deposition of Cu resulted in the formation of a shiny copper film that failed the Scotch Tape test. Results indicate failure mainly at the Ru/OSG interface.

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The Role of MW Plasma Treatment on the Corrosion Resistance of Stainless Steels

Archives of Metallurgy and Materials ◽

10.2478/amm-2013-0143 ◽

2013 ◽

Vol 58 (4) ◽

pp. 1169-1175 ◽

Cited By ~ 1

Author(s):

D. Kasprzyk ◽

B. Stypuła ◽

P. Kustrowski ◽

M. Drozdek

Keyword(s):

Corrosion Resistance ◽

Plasma Treatment ◽

Stainless Steels ◽

Photoelectron Spectroscopy ◽

Electron Cyclotron Resonance ◽

Nitrogen Plasma ◽

Pitting Corrosion Resistance ◽

Composition And Structure ◽

Steel Surfaces

Abstract Two stainless steels (S32404 duplex and S32615 austenitic) were subject to the carbon/nitrogen plasma treatment to examine the role of alloy composition and structure in the behavior of surface during modification. The modification process was performed in the electron cyclotron resonance (ECR) micro wave plasma system, with the frequency of 2.45 GHz and the generator power of 350 W, and with the use of reactive gas mixtures containing CH4 and N2, at the low temperature of 400°C and under pressure of 0.2Tr. The treated surface was analyzed by means of X-ray photoelectron spectroscopy (XPS). The corrosion resistance of the samples was determined on the basis of LSV polarization curves in 3% sodium chloride solution at 37°C. The treated steel surfaces showed a higher tendency for passivation and higher pitting corrosion resistance compared to the non-modified surfaces.

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The Influence of Hydrogen Addition on the Chemical Properties of Hydrogenated Aluminum Nitride Films Prepared by RF Reactive Sputtering

MRS Proceedings ◽

10.1557/proc-449-999 ◽

1996 ◽

Vol 449 ◽

Cited By ~ 2

Author(s):

Jai-Young Lee ◽

Yoon-Joong Yong

Keyword(s):

Aluminum Nitride ◽

Photoelectron Spectroscopy ◽

Rutherford Backscattering Spectrometry ◽

Chemical Properties ◽

Binding Energies ◽

Hydrogen Addition ◽

Partial Pressures ◽

Oxygen Impurities ◽

Reactive Gas

ABSTRACTHydrogenated aluminum nitride (A1N:H) films have been deposited on the (100) silicon wafers by the RF reactive magnetron sputtering method with H2 gas in addition to an Ar-N2 gas mixture. Stoichiometric A1N films without oxygen impurities can be prepared by adding 10 % H2 to reactive gas, which is proven by Rutherford Backscattering Spectrometry (RBS). The bonding aspects of Al, N, O and H atoms in A1N:H films have been examined by X-ray Photoelectron Spectroscopy (XPS) and Fourier Transform Infrared (FTIR) to understand the effects of H2 addition. The chemical shift of the binding energies of A1, N and O atoms in A1N:H films from XPS analysis and the change of N-H bonding in FTIR with respect to different partial pressures of H2 gas have been confirmed. The role of H atoms is suggested to facilitate bonding with unbound N atoms in A1N:H films and hinder N-O bonding, thus, reducing oxygen concentration in A1N:H films. Also, the activation energy for the evolution of H2 gas from A1N:H film has been determined to be 0.11 eV/atom through a Kissinger-type analysis by a thermal desorption test using Gas Chromatograph(GC). This result implies that the hydrogen atom in film forms the hydrogen bond.

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Crystal Structure Analysis of Cu-Zr Alloys by Convergent Beam Diffraction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100098277 ◽

1981 ◽

Vol 39 ◽

pp. 354-355

Author(s):

A. F. Marshall ◽

J. W. Steeds ◽

D. Bouchet ◽

S. L. Shinde ◽

R. G. Walmsley

Keyword(s):

Crystal Structure ◽

Point Group ◽

Intermetallic Phase ◽

Three Dimensional ◽

Crystal Structure Analysis ◽

Ion Milling ◽

Composition And Structure ◽

Unit Cells ◽

Sputter Deposited ◽

Convergent Beam

Convergent beam electron diffraction is a powerful technique for determining the crystal structure of a material in TEM. In this paper we have applied it to the study of the intermetallic phases in the Cu-rich end of the Cu-Zr system. These phases are highly ordered. Their composition and structure has been previously studied by microprobe and x-ray diffraction with sometimes conflicting results.The crystalline phases were obtained by annealing amorphous sputter-deposited Cu-Zr. Specimens were thinned for TEM by ion milling and observed in a Philips EM 400. Due to the large unit cells involved, a small convergence angle of diffraction was used; however, the three-dimensional lattice and symmetry information of convergent beam microdiffraction patterns is still present. The results are as follows:1) 21 at% Zr in Cu: annealed at 500°C for 5 hours. An intermetallic phase, Cu3.6Zr (21.7% Zr), space group P6/m has been proposed near this composition (2). The major phase of our annealed material was hexagonal with a point group determined as 6/m.

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Long-term dynamics and destruction of marsh vegetation in the Kolokolkova Bay of the Barents Sea

Vegetation of Russia ◽

10.31111/vegrus/2012.21.66 ◽

2012 ◽

pp. 66-77 ◽

Cited By ~ 4

Author(s):

I. A. Lavrinenko ◽

O. V. Lavrinenko ◽

D. V. Dobrynin

Keyword(s):

Species Composition ◽

Plant Communities ◽

Barents Sea ◽

Mean Value ◽

Marsh Vegetation ◽

Composition And Structure ◽

The Mean ◽

Species Composition And Structure

The satellite images show that the area of marshes in the Kolokolkova bay was notstable during the period from 1973 up to 2011. Until 2010 it varied from 357 to 636 ha. After a severe storm happened on July 24–25, 2010 the total area of marshes was reduced up to 43–50 ha. The mean value of NDVI for studied marshes, reflecting the green biomass, varied from 0.13 to 0.32 before the storm in 2010, after the storm the NDVI decreased to 0.10, in 2011 — 0.03. A comparative analysis of species composition and structure of plant communities described in 2002 and 2011, allowed to evaluate the vegetation changes of marshes of the different topographic levels. They are following: a total destruction of plant communities of the ass. Puccinellietum phryganodis and ass. Caricetum subspathaceae on low and middle marches; increasing role of halophytic species in plant communities of the ass. Caricetum glareosae vic. Calamagrostis deschampsioides subass. typicum on middle marches; some changes in species composition and structure of plant communities of the ass. Caricetum glareosae vic. Calamagrostis deschampsioides subass. festucetosum rubrae on high marches and ass. Parnassio palustris–Salicetum reptantis in transition zone between marches and tundra without changes of their syntaxonomy; a death of moss cover in plant communities of the ass. Caricetum mackenziei var. Warnstorfia exannulata on brackish coastal bogs. The possible reasons of dramatic vegetation dynamics are discussed. The dating of the storm makes it possible to observe the directions and rates of the succession of marches vegetation.

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Board of Director Characteristics, Institutional Ownership, and Fraud: Evidence from Australia

Auditing A Journal of Practice & Theory ◽

10.2308/aud.2004.23.2.105 ◽

2004 ◽

Vol 23 (2) ◽

pp. 105-117 ◽

Cited By ~ 93

Author(s):

Vineeta D. Sharma

Keyword(s):

Research Evidence ◽

Institutional Ownership ◽

Board Of Director ◽

Composition And Structure ◽

High Incidence ◽

The Board Of Directors ◽

Director Characteristics ◽

The Relationship ◽

The U.S

Due to the high incidence of fraud in Australia, regulatory reports suggest strengthening the monitoring role of the board of directors (BOD). These reports recommend greater independence and no duality (chairperson of the BOD should not be the CEO) on the BOD. While there is no Australian evidence, research evidence in the U.S. supports these suggested reforms. It is not clear whether the research evidence observed in the U.S. will generalize to the Australian setting because of contextual differences. This study extends the U.S. findings to the Australian context and investigates the relationship between two attributes of the BOD, independence and duality, and fraud. In addition, I examine whether institutional ownership plays a role in the context of fraud. The more highly concentrated institutional ownership in Australia suggests the presence of some relationship. Using a matched sample of fraud and no-fraud firms from 1988–2000, I find that as the percentage of independent directors and the percentage of independent institutional ownership increases, the likelihood of fraud decreases. As expected, the results show a positive relationship between duality and the likelihood of fraud. These results support the call for strengthening the composition and structure of the BOD in Australia.

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Performance Improvement of ZnSnO Thin-Film Transistors with Low-Temperature Self-Combustion Reaction

Electronics ◽

10.3390/electronics10091099 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1099

Author(s):

Ye-Ji Han ◽

Se Hyeong Lee ◽

So-Young Bak ◽

Tae-Hee Han ◽

Sangwoo Kim ◽

...

Keyword(s):

Thin Film ◽

Photoelectron Spectroscopy ◽

Large Scale ◽

Low Cost ◽

Thermal Analyses ◽

Thin Film Transistor ◽

Sol Gel ◽

Annealing Temperatures ◽

Zinc Tin Oxide ◽

Thermal Limitation

Conventional sol-gel solutions have received significant attention in thin-film transistor (TFT) manufacturing because of their advantages such as simple processing, large-scale applicability, and low cost. However, conventional sol-gel processed zinc tin oxide (ZTO) TFTs have a thermal limitation in that they require high annealing temperatures of more than 500 °C, which are incompatible with most flexible plastic substrates. In this study, to overcome the thermal limitation of conventional sol-gel processed ZTO TFTs, we demonstrated a ZTO TFT that was fabricated at low annealing temperatures of 350 °C using self-combustion. The optimized device exhibited satisfactory performance, with μsat of 4.72 cm2/V∙s, Vth of −1.28 V, SS of 0.86 V/decade, and ION/OFF of 1.70 × 106 at a low annealing temperature of 350 °C for one hour. To compare a conventional sol-gel processed ZTO TFT with the optimized device, thermogravimetric and differential thermal analyses (TG-DTA) and X-ray photoelectron spectroscopy (XPS) were implemented.

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Yttrium doped phosphate-based glasses: structural and degradation analyses

Biomedical glasses ◽

10.1515/bglass-2020-0004 ◽

2020 ◽

Vol 6 (1) ◽

pp. 34-49

Author(s):

Abul Arafat ◽

Sabrin A. Samad ◽

Jeremy J. Titman ◽

Andrew L. Lewis ◽

Emma R. Barney ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Structural Changes ◽

Xrd Analysis ◽

Calcium Pyrophosphate ◽

Ion Release ◽

Subsequent Increase ◽

Structural Characterisation ◽

Release Studies ◽

Degradation Properties

AbstractThis study investigates the role of yttrium in phosphate-based glasses in the system 45(P2O5)–25(CaO)– (30-x)(Na2O)–x(Y2O3) (0≤x≤5) prepared via melt quenching and focuses on their structural characterisation and degradation properties. The structural analyses were performed using a combination of solid-state nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). 31P NMR analysis showed that depolymerisation of the phosphate network occurred which increased with Y2O3 content as metaphosphate units (Q2) decreased with subsequent increase in pyrophosphate species (Q1). The NMR results correlated well with structural changes observed via FTIR and XPS analyses. XRD analysis of crystallised glass samples revealed the presence of calcium pyrophosphate (Ca2P2O7) and sodium metaphosphate (NaPO3) phases for all the glass formulations explored. Yttrium-containing phases were found for the formulations containing 3 and 5 mol% Y2O3. Degradation analyses performed in Phosphate buffer saline (PBS) and Milli-Q water revealed significantly reduced rates with addition of Y2O3 content. This decrease was attributed to the formation of Y-O-P bonds where the octahedral structure of yttrium (YO6) cross-linked phosphate chains, subsequently leading to an increase in chemical durability of the glasses. The ion release studies also showed good correlation with the degradation profiles.

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