A quantitative investigation of thin specimen X-ray spectra in the TEM

1978 ◽  
Vol 36 (1) ◽  
pp. 550-551
Author(s):  
B.W. Robertson ◽  
J.N. Chapman ◽  
W.A.P. Nicholson ◽  
R.P. Ferrier
Keyword(s):  
Electron Microscope ◽  
Electron Probe ◽  
X Rays ◽  
Quantitative Investigation ◽  
Solid Materials ◽  
Thin Specimen ◽  
X Ray ◽  
Transmission Electron ◽  
Extraneous Radiation ◽  
The Continuum

In electron probe x-ray microanalysis, the observed x-ray spectra are degraded by the presence of both characteristic and bremsstrahlung x-rays from the regions of the specimen which are not under analysis and from the solid materials near the specimen. These x-rays are generated by electrons scattered from the probe by the specimen and by stray electrons originally outside the probe. The extraneous bremsstrahlung x-rays form a component of the observed continuum which is only indirectly dependent on the nature of the specimen. This effect is particularly undesirable in the analysis of thin biological specimens in the transmission electron microscope since the continuum level is commonly used in quantitative analysis as a measure of specimen mass thickness. Experiments have therefore been performed to investigate the magnitude of the extraneous radiation and to evaluate the success of attempts to reduce it. These have been detailed elsewhere (Nicholson et al. 1977).

An Investigation of the Pyroantimonate Reaction for Sodium Localisation Using the Analytical Electron Microscope, EMMA-4

1971 ◽  
Vol 29 ◽  
pp. 406-407
Author(s):  
L. Herman ◽  
T. Sato ◽  
B. A. Weavers
Keyword(s):  
Electron Microscope ◽  
X Rays ◽  
X Ray ◽  
Transmission Electron ◽  
Analytical Electron ◽  
Analytical Electron Microscope ◽  
Viewing Screen ◽  
Conventional Transmission Electron Microscope ◽  
The Continuum

The analytical electron microscope, EMMA-4, is designed specifically to perform x-ray microanalysis of conventional transmission electron microscope specimens.The analysis facilities consist of two fully focussing crystal spectrometers each of which can be tuned to collect x-rays emitted from elements of atomic number greater than 11. In addition to the two crystal spectrometers there is a non-dispersive detector which can be used to monitor the total x-ray emission of the specimen and adds the facility for determination of the “continuum” radiation for quantitative analysis. The exact area of analysis is always located by direct observation of the viewing screen.

High Spatial Resolution Compositional Analysis at Interfaces

1980 ◽  
Vol 38 ◽  
pp. 356-359
Author(s):  
John B. Vander Sande ◽  
Thomas F. Kelly ◽  
Douglas Imeson
Keyword(s):  
Electron Microscope ◽  
High Spatial Resolution ◽  
Compositional Analysis ◽  
Scanning Transmission Electron Microscope ◽  
Thin Specimen ◽  
X Ray ◽  
Volume Of Interest ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Electron Energy Loss

In the scanning transmission electron microscope (STEM) a fine probe of electrons is scanned across the thin specimen, or the probe is stationarily placed on a volume of interest, and various products of the electron-specimen interaction are then collected and used for image formation or microanalysis. The microanalysis modes usually employed in STEM include, but are not restricted to, energy dispersive X-ray analysis, electron energy loss spectroscopy, and microdiffraction.

Combined Plasma-Microincineration, Electron Microscopy And Electron Probe Microanalysis For Fine Localization of Biological Mineral Substances

1973 ◽  
Vol 31 ◽  
pp. 334-335 ◽  
Author(s):  
Richard S. Thomas ◽  
Mabel I. Corlett
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Electron Probe ◽  
Oxygen Plasma ◽  
Chemical Nature ◽  
The Other ◽  
X Ray ◽  
Transmission Electron ◽  
Mineral Substances ◽  
Fine Localization

Ash patterns produced by oxygen plasma microincineration(OPM) of thin-sectioned biological materials and examined with the transmission electron microscope (TEM) can show unambiguously the distribution of mineral substances in the specimen with resolutions down to 100 Å. The chemical nature of the mineral is not demonstrated, however. Electron-probe X-ray microanalysis (EXM), on the other hand, can determine precisely the nature of the mineral in ashgd or unashed sections but its spatial resolution is limited to 1000-10,000 A at best. Also its sensitivity of analysis on unashed specimens is limited by intolerance of the specimen to high beam intensities. Using both TEM and EXM together on ash patterns of suitable specimens can overcome their independent spatial and chemical limitations. Furthermore, use of OPM produces a highly stable mineral specimen for EXM, thereby improving sensitivity.

Routine Determination of X-Ray Detector Efficiencies Using Submicron Spheres of Pure Materials

1985 ◽  
Vol 43 ◽  
pp. 416-417
Author(s):  
Thomas F. Kelly
Keyword(s):  
Electron Microscope ◽  
Energy Range ◽  
Transmission Electron Microscope ◽  
Weight Fraction ◽  
Characteristic Line ◽  
X Rays ◽  
Detector Efficiency ◽  
X Ray ◽  
Transmission Electron

The purpose of this paper is to outline an approach to routine determination of x-ray detector efficiencies over the entire applicable energy range that may be used on any transmission electron microscope.BACKGROUNDThe quantification of x-ray intensities using the ratio technique can be accomplished [see, for example, 1] using a relation of the form:Here, for element A, CA is the composition in the sample as a weight fraction, kA is the x-ray generation constant (see below) which contains only sample-dependent information, eA is the detector efficiency for characteristic x-rays which contains only detector-dependent information, and lA is the measured x-ray intensity in a characteristic line.

The Analysis of Particles With Energy Dispersive X-Ray Spectroscopy (EDS)

1998 ◽  
Vol 4 (S2) ◽  
pp. 184-185
Author(s):  
J. A. Small ◽  
J. A. Armstrong ◽  
D. S. Bright ◽  
B. B. Thorne
Keyword(s):  
Electron Microscope ◽  
Elemental Analysis ◽  
Electron Probe ◽  
Initial Particle ◽  
X Ray ◽  
Transmission Electron ◽  
Analytical Electron ◽  
Analytical Electron Microscope ◽  
The Individual ◽  
Individual Particles

The addition of the Si-Li detector to the electron probe, the scanning electron microscope, and more recently the transmission electron microscope (resulting in the analytical electron microscope) has made it possible to obtain elemental analysis on individual “particles” with dimensions less than 1 nm using EDS. Although some initial particle studies on micrometer-sized particles were done on the electron probe using wavelength dispersive spectrometers, WDS, the variability and complexity of many particle compositions coupled with the high currents necessary for WDS made elemental analysis of particles by WDS difficult at best. In addition, the use of multiple spectrometers, each with a different view of the particle and therefore different particle geometry as shown in Fig. 1, limited the quantitative capabilities of the technique. With the introduction of the Si-Li detector, there was only one spectrometer with a single geometry resulting in the development of various procedures for obtaining quantitative elemental analysis of the individual particles.

X-Ray Microanalysis of Al/Zr Multilayers in the Transmission Electron Microscope

1997 ◽  
Vol 472 ◽  
Author(s):  
M. A. Wall ◽  
T. W. Barbee ◽  
J. Bentley
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Electron Probe ◽  
Nanometer Scale ◽  
Line Profiles ◽  
Electron Microscopic ◽  
X Ray ◽  
Transmission Electron ◽  
Interface Layers

ABSTRACTA one-nanometer scale transmission electron microscope electron probe X-ray microanalysis characterization of as-deposited and annealed aluminum - 11.5 at.% zirconium multilayer samples in cross-section synthesized by magnetron sputtering is reported on here. Composition line profiles were acquired across Zr layers in as-deposited material and samples isochronnally annealed in a differential scanning calorimeter to temperatures of 290°C and 485°C. A spatial resolution of approximaty 1.5 to 2.0 nm was achieved in these experiments and will be improved by deconvoluti on of the instrumental electron probe function from the data. The as-deposited structure consisted of crystalline Al and Zr layers with thin amorphous layers at the Al/Zr interfaces. The amorphous interface layers increased in thickness upon annealing to 290°C. Additionally, at 290”C a metastable cubic alloy forms at the Zr deposited on Al interface. Upon heating to 485°C a multilayer of Al and metastable cubic AlxZr1-x phase is formed. The electron microscopic experimental technique, observations and data analysis will be discussed as applied to these multilayered materials.

IN SITU ASSEMBLY OF ZnS NANOFIBERS WITH HIGHLY ORDERED LAMELLAR MESOSTRUCTURE

2006 ◽  
Vol 05 (02n03) ◽  
pp. 245-251 ◽  
Author(s):  
JUNPING LI ◽  
YAO XU ◽  
DONG WU ◽  
YUHAN SUN
Keyword(s):  
Electron Microscope ◽  
Thermal Analyses ◽  
Blue Shift ◽  
X Rays ◽  
Energy Dispersive Analysis ◽  
Visible Absorption ◽  
X Ray ◽  
Transmission Electron ◽  
Uv Visible

ZnS nanofibers with lamellar mesostructure could be built up from in situ generated ZnS precursors via hydrothermal routes using neutral n-alkylamines as structure-directing template and ethylene diamine tetraacetic acid (EDTA) as stabilizer. The morphology and structure of the obtained products were thoroughly investigated via scanning electron microscope (SEM), energy dispersive analysis of X-rays (EDX), transmission electron microscope (TEM), X-ray powder diffraction (XRD) and thermal analyses. HRTEM and XRD results revealed that the so-produced nanofibers were lamellar mesostructure and its framework was built of crystalline wurtzite ZnS . It was also found that the distance between the layers was proportional to the chain length of the alkylamine. The UV-visible absorption spectrum showed that the nanofibers exhibited strong quantum-confined effect with a blue shift in the band gap. Finally, a probable mechanism for the assembly of the nanofibers was also proposed.

Practical X-ray Spectrometry with Second-Generation Microcalorimeter Detectors

2012 ◽  
Vol 20 (4) ◽  
pp. 38-42 ◽  
Author(s):  
Robin Cantor ◽  
Hideo Naito
Keyword(s):  
Electron Microscope ◽  
Spatial Resolution ◽  
Energy Resolution ◽  
Semiconductor Industry ◽  
High Energy ◽  
High Energy Resolution ◽  
X Rays ◽  
X Ray ◽  
Analytical Technique ◽  
Transmission Electron

X-ray spectroscopy is a widely used and extremely sensitive analytical technique for qualitative as well as quantitative elemental analysis. Typically, high-energy-resolution X-ray spectrometers are integrated with a high-spatial-resolution scanning electron microscope (SEM) or transmission electron microscope (TEM) for X-ray microanalysis applications. The focused electron beam of the SEM or TEM excites characteristic X rays that are emitted by the sample. The integrated X-ray spectrometer can then be used to identify and quantify the elemental composition of the sample on a sub-micron length scale. This combination of energy resolution and spatial resolution makes X-ray microanalysis of great importance to the semiconductor industry.

X-ray Determination and Finite-Element Modeling of Stress in Passivated Al-0.5%Cu Lines During Thermal Cycling.

1993 ◽  
Vol 309 ◽  
Author(s):  
Paul R. Besser ◽  
Anne Sauter Mack ◽  
David Fraser ◽  
John C. Bravman
Keyword(s):  
Finite Element ◽  
Electron Microscope ◽  
Strain State ◽  
Room Temperature ◽  
Scanning Transmission Electron Microscope ◽  
X Rays ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Voltage Scanning

AbstractWe have measured the principal strain state of AI-0.5%Cu lines passivated with silicon nitride directly and used it to calculate the stress state. The stress was determined as the lines were thermally cycled from room temperature to 450°C. The general stress-temperature behavior shows good fundamental agreement with that calculated using finite-element methods, although the magnitude of the stresses measured with x-rays is less than that predicted by modeling due to stressinduced voiding in the lines. This is shown with a high voltage scanning transmission electron microscope (STEM) operated in the backscattering mode.

Transmission electron microscopy (TEM) of Earth and planetary materials: A review

2010 ◽  
Vol 74 (1) ◽  
pp. 1-27 ◽  
Author(s):  
M. R. Lee
Keyword(s):  
Electron Microscope ◽  
Electron Diffraction ◽  
Transmission Electron Microscope ◽  
Electron Spectroscopy ◽  
Atomic Resolution ◽  
Diffraction Spectrum ◽  
X Rays ◽  
X Ray ◽  
Transmission Electron ◽  
Planetary Materials

AbstractUsing high intensity beams of fast electrons, the transmission electron microscope (TEM) and scanning transmission electron microscope (STEM) enable comprehensive characterization of rocks and minerals at micrometre to sub-nanometre scales. This review outlines the ways in which samples of Earth and planetary materials can be rendered sufficiently thin for TEM and STEM work, and highlights the significant advances in site-specific preparation enabled by the focused ion beam (FIB) technique. Descriptions of the various modes of TEM and STEM imaging, electron diffraction and X-ray and electron spectroscopy are outlined, with an emphasis on new technologies that are of particular relevance to geoscientists. These include atomic-resolution Z-contrast imaging by high-angle annular dark-field STEM, electron crystallography by precession electron diffraction, spectrum mapping using X-rays and electrons, chemical imaging by energy-filtered TEM and true atomic-resolution imaging with the new generation of aberration-corrected microscopes. Despite the sophistication of modern instruments, the spatial resolution of imaging, diffraction and X-ray and electron spectroscopy work on many natural materials is likely to remain limited by structural and chemical damage to the thin samples during TEM and STEM.

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