Electron energy-loss spectrometry on thin amorphous carbon films: Accurate determination of the plasmon energy

AbstractMonochromated electron energy-loss spectroscopy (EELS) is employed to determine the optical properties of carbonaceous aerosols from the infrared to the ultraviolet region of the spectrum. It is essential to determine their optical properties to understand their accurate contribution to radiative forcing for climate change. The influence of surface and interface plasmon effects on the accuracy of dielectric data determined from EELS is discussed. Our measurements show that the standard thin film formulation of Kramers−Kronig analysis can be employed to make accurate determination of the dielectric function for carbonaceous particles down to about 40 nm in size. The complex refractive indices of graphitic and amorphous carbon spherules found in the atmosphere were determined over the wavelength range 200–1,200 nm. The graphitic carbon was strongly absorbing black carbon, whereas the amorphous carbon shows a more weakly absorbing brown carbon profile. The EELS approach provides an important tool for exploring the variation in optical properties of atmospheric carbon.

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Characterization of hard carbon films by electron energy loss spectrometry

Thin Solid Films ◽

10.1016/0040-6090(79)90451-6 ◽

1979 ◽

Vol 61 (2) ◽

pp. L1-L4 ◽

Cited By ~ 48

Author(s):

Chr. Weissmantel ◽

K. Bewilogua ◽

C. Schürer ◽

K. Breuer ◽

H. Zscheile

Keyword(s):

Energy Loss ◽

Electron Energy ◽

Carbon Films ◽

Hard Carbon ◽

Electron Energy Loss Spectrometry ◽

Electron Energy Loss

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High-resolution electron energy-loss spectroscopy of undoped and nitrogen-doped tetrahedral amorphous carbon films

Diamond and Related Materials ◽

10.1016/s0925-9635(99)00322-2 ◽

2000 ◽

Vol 9 (3-6) ◽

pp. 722-727 ◽

Cited By ~ 29

Author(s):

S. Waidmann ◽

M. Knupfer ◽

J. Fink ◽

B. Kleinsorge ◽

J. Robertson

Keyword(s):

High Resolution ◽

Energy Loss ◽

Amorphous Carbon ◽

Electron Energy Loss Spectroscopy ◽

Carbon Films ◽

Amorphous Carbon Films ◽

Nitrogen Doped ◽

Tetrahedral Amorphous Carbon ◽

Resolution Electron ◽

Electron Energy Loss

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The Application of Electron Energy Loss Spectroscopy in Glass - Ceramic Microstructural Analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100078778 ◽

1977 ◽

Vol 35 ◽

pp. 250-251

Author(s):

R. M. Anderson ◽

A. Kumar

Keyword(s):

Energy Loss ◽

Electron Energy ◽

Microstructural Analysis ◽

Elemental Content ◽

Light Elements ◽

X Ray ◽

Electron Energy Loss Spectrometry ◽

C And N ◽

Electron Energy Loss

The identification of unknown phases in crystallized glasses or ceramics has been difficult because the phases are generally composed of many elements; they crystallize into low-symmetry lattices; they contain numerous impurities, which may alter crystal structure or allow the observation of metastable phases; and they are not well represented in standard compilations of crystal data. Compounding the problem is the fact that energy- dispersive x-ray analysis (EDX) for elemental content can not be employed for elements with Z<11. This eliminates any possibility of qualitative analysis of the important Li, Be, and B glasses as well as determination of O, C and N content. Electron Energy Loss Spectrometry (ELS) has been shown to be a powerful method for the analysis of light elements. The ELS method is far more efficient at detecting light elements than x-ray detection, because the yield of energy loss electrons to inner shell excitation and ionizations is unity and because the electrons, which have lost energy encountering the sample, are scattered through very small angles, with the result that collection efficiencies are high.

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In Situ Analysis of Surface Contaminant Desorption during Low-Temperature Silicon Substrate Cleaning using Reflection Electron Energy Loss Spectrometry

MRS Proceedings ◽

10.1557/proc-259-449 ◽

1992 ◽

Vol 259 ◽

Cited By ~ 1

Author(s):

Selmer S. Wong ◽

Shouleh Nikzad ◽

Channing C. Ahn ◽

Aimee L. Smith ◽

Harry A. Atwater

Keyword(s):

Low Temperature ◽

Energy Loss ◽

Electron Energy ◽

Core Loss ◽

Temperature Dependent ◽

Electron Energy Loss Spectrometry ◽

Analysis Technique ◽

Chemical Analysis Technique ◽

Electron Energy Loss

ABSTRACTWe have employed reflection electron energy loss spectrometry (REELS), a surface chemical analysis technique, in order to analyze contaminant coverages at the submonolayer level during low-temperature in situ cleaning of hydrogen-terminated Si(100). The chemical composition of the surface was analyzed by measurements of the C K, O K and Si L2,3 core loss intensities at various stages of the cleaning. These results were quantified using SiC(100) and SiO2 as reference standards for C and O coverage. Room temperature REELS core loss intensity analysis after sample insertion reveals carbon at fractional monolayer coverage. We have established the REELS detection limit for carbon coverage to be 5±2% of a monolayer. A study of temperature-dependent hydrocarbon desorption from hydrogen-terminated Si(100) reveals the absence of carbon on the surface at temperatures greater than 200°C. This indicates the feasibility of epitaxial growth following an in situ low-temperature cleaning and also indicates the power of REELS as an in situ technique for assessment of surface cleanliness.

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