EELS analysis of vacuum arc-deposited diamond-like films

Berger, S. D.; McKenzie, David R.; Martin, Phil

doi:10.1080/09500838808214715

Cited by 572 publications

(171 citation statements)

References 4 publications

Supporting

Mentioning

162

Contrasting

Unclassified

Order By: Relevance

“…Even though EELS allows the fraction of carbon atoms in sp 2 -and sp 3 -hybridization state to be quantified through the analysis of the low loss region (from 0 to 40 eV) or the high loss region at the C1s 11,15,[36][37][38] , it requires the film to be removed from the substrate or for a cross-section to be produced. Additionally, the acquisition of the C1s is usually carried out with limited energy resolution of approximately 0.5 eV 11,44 .…”

Section: Introductionmentioning

confidence: 99%

Quantitative Evaluation of the Carbon Hybridization State by Near Edge X-ray Absorption Fine Structure Spectroscopy

2016

View full text Add to dashboard Cite

The characterization of the local bonding configuration of carbon in carbon-based materials is of paramount importance since the properties of such materials strongly depend on the distribution of carbon hybridization states, the local ordering, and the degree of hydrogenation. Carbon 1s near edge X-ray absorption fine structure (NEXAFS) spectroscopy is one of the most powerful techniques for gaining insights into the bonding configuration of near-surface carbon atoms. The common methodology for quantitatively evaluating the carbon hybridization state using C1s NEXAFS measurements, which is based on the analysis of the sample of interest and of a highly ordered pyrolytic graphite (HOPG) reference sample, was reviewed and critically assessed, noting that inconsistencies are found in the literature in applying this method. A theoretical rationale for the specific experimental conditions to be used for the acquisition of HOPG reference spectra is presented together with the potential sources of uncertainty and errors in the correctly computed fraction of sp 2 -bonded carbon. This provides a specific method for analyzing the distribution of carbon hybridization state using NEXAFS spectroscopy. As an illustrative example, a hydrogenated amorphous carbon film was analyzed using this method, and showed good agreement with X-ray photoelectron spectroscopy (which is surface sensitive).Furthermore, the results were consistent with analysis from Raman spectroscopy (which is not surface sensitive), indicating the absence of a structurally different near-surface region in this particular thin film material. The present work can assist surface scientists in the analysis of NEXAFS spectra for the accurate characterization of the structure of carbon-based materials.3

show abstract

Section: Introductionmentioning

confidence: 99%

Quantitative Evaluation of the Carbon Hybridization State by Near Edge X-ray Absorption Fine Structure Spectroscopy

2016

View full text Add to dashboard Cite

show abstract

“…B, Synthetic cubic NDs. C, YDB n-diamonds from Murray Springs; solid lines represent spectra for graphite, amorphous carbon, n-diamond, and i-carbon from Berger et al (1988); the graphene spectrum is from Daulton et al (2010). A color version of this figure is available online.…”

Section: Tem Sad and Scanning Electron Microscopy Of Ndsmentioning

confidence: 99%

Nanodiamond-Rich Layer across Three Continents Consistent with Major Cosmic Impact at 12,800 Cal BP

Kinzie¹,

Hee

Stich

et al. 2014

The Journal of Geology

170

View full text Add to dashboard Cite

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org. A B S T R A C TA major cosmic-impact event has been proposed at the onset of the Younger Dryas (YD) cooling episode at ≈12,800 ‫ע‬ 150 years before present, forming the YD Boundary (YDB) layer, distributed over 150 million km 2 on four continents. In 24 dated stratigraphic sections in 10 countries of the Northern Hemisphere, the YDB layer contains a clearly defined abundance peak in nanodiamonds (NDs), a major cosmic-impact proxy. Observed ND polytypes include cubic diamonds, lonsdaleite-like crystals, and diamond-like carbon nanoparticles, called n-diamond and i-carbon. The ND abundances in bulk YDB sediments ranged up to ≈500 ppb (mean: 200 ppb) and that in carbon spherules up to ≈3700 ppb (mean: ≈750 ppb); 138 of 205 sediment samples (67%) contained no detectable NDs. Isotopic evidence indicates that YDB NDs were produced from terrestrial carbon, as with other impact diamonds, and were not derived from the impactor itself. The YDB layer is also marked by abundance peaks in other impact-related proxies, including cosmic-impact spherules, carbon spherules (some containing NDs), iridium, osmium, platinum, charcoal, aciniform carbon (soot), and high-temperature melt-glass. This contribution reviews the debate about the presence, abundance, and origin of the concentration peak in YDB NDs. We describe an updated protocol for the extraction and concentration of NDs from sediment, carbon spherules, and ice, and we describe the basis for identification and classification of YDB ND polytypes, using nine analytical approaches. The large body of evidence now obtained about YDB NDs is strongly consistent with an origin by cosmic impact at ≈12,800 cal BP and is inconsistent with formation of YDB NDs by natural terrestrial processes, including wildfires, anthropogenesis, and/or influx of cosmic dust.

show abstract

“…by comparison with a reference spectrum of known sp 3 content collected under the same conditions [11]. Following Berger et al [11] and McCulloch et al [12], the sp 3 fraction f for a specimen of interest can be estimated using equation (1):…”

Section: Lbnl-59023mentioning

confidence: 99%

“…Following Berger et al [11] and McCulloch et al [12], the sp 3 fraction f for a specimen of interest can be estimated using equation (1):…”

Section: Lbnl-59023mentioning

confidence: 99%

Plasma biasing to control the growth conditions of diamond-like carbon

Anders¹,

Pasaja²,

Lim³

et al. 2007

Surface and Coatings Technology

View full text Add to dashboard Cite

It is well known that the structure and properties of diamond-like carbon, and in particular the sp /sp ratio, can be controlled by the energy of the condensing carbon ions or atoms. In many practical cases, the energy of ions arriving at the surface of the growing film is determined by the bias applied to the substrate. The bias causes a sheath to form between substrate and plasma in which the potential difference between plasma potential and surface potential drops. In this contribution, we demonstrate that the same results can be obtained with grounded substrates by shifting the plasma potential. This "plasma biasing" (as opposed to "substrate biasing") is shown to work well with pulsed cathodic carbon arcs, resulting in tetrahedral amorphous carbon (ta-C) films that are comparable to the films obtained with the conventional substrate bias. To verify the plasma bias approach, ta-C films were deposited by both conventional and plasma bias and characterized by transmission electron microscopy (TEM) and electron energy loss spectrometry (EELS). Detailed data for comparison of these films are provided.

show abstract

EELS analysis of vacuum arc-deposited diamond-like films

Cited by 572 publications

References 4 publications

Quantitative Evaluation of the Carbon Hybridization State by Near Edge X-ray Absorption Fine Structure Spectroscopy

Quantitative Evaluation of the Carbon Hybridization State by Near Edge X-ray Absorption Fine Structure Spectroscopy

Nanodiamond-Rich Layer across Three Continents Consistent with Major Cosmic Impact at 12,800 Cal BP

Plasma biasing to control the growth conditions of diamond-like carbon

Contact Info

Product

Resources

About