Microanalysis with high Spatial Resolution

1983 ◽  
Vol 31 ◽  
Author(s):  
P. E. Batson ◽  
C. R. M. Grovenor ◽  
D. A. Smith ◽  
C. Wong

ABSTRACTElemental microanalysis, using x-rays and electron energy loss scattering, has been shown to be possible with electron beam probe sizes down to 0.5nm. This paper will discuss some practical problems, such as specimen drift, signal magnitude, and probe-specimen interaction when the probe is made very small. These problems have arisen in two studies: 1) an investigation of as segregation in poly-crystalline Si and 2) imaging of metal spheres with surface and bulk plasmon inelastic scattering.

Author(s):  
M. R. Scheinfein

There has been considerable interest in characterizing the electronic and chemical properties of interfaces and grain boundries at high spatial resolution. This abstract describes a technique which utilizes the energy dispersion of surface plasmons in the transmission electron energy loss spectrum to evaluate the local dielectric constant variation across interfaces. This technique is shown to yield extremely high spatial resolution.We have been conducting studies of interfaces in a VG HB-5 STEM located at NRRFSS which is equipped with a high resolution electron energy loss analyzer. In STEM, using small probes, a typical surface plasmon excited by 100 keV electrons (Al for example) reaches its asymptotic energy value at a scattering angle between.3 and.4 mr. Since we are convoluting the incident angular distribution with the surface plasmon intensities integrated over a collection aperture, the surface plasmon excitation energies are given by their asymptotic (in k-space) energy values. These asymptotic energy excitations are very sensitive functions of the thickness and dielectric constant [eg, 2-5] of the surrounding medium.


1985 ◽  
Vol 62 ◽  
Author(s):  
Mark M. Disko

ABSTRACTTransition metal carbides and nitrides are important in a wide range of materials problems which include precipitates in high strength alloys and ceramic wear coatings. Electron energy loss spectroscopy (EELS) is a high spatial resolution (probe sizes < 100nm) analytical technique which is sensitive to variations in carbon or nitrogen stoichiometry. This sensitivity to light elements depends on the ability to relate the measured EELS spectrum to a material's electronic structure. The unique capabilities of EELS for the characterization of carbonitrides with high spatial resolution are discussed along with some of the experimental and analytical methods used to relate measured spectra to electronic structure. Data are presented for several members of the systems Ti-N-C and Cr-Fe-C.


2016 ◽  
Vol 22 (S3) ◽  
pp. 992-993 ◽  
Author(s):  
Kartik Venkatraman ◽  
Qianlang Liu ◽  
Toshihiro Aoki ◽  
Peter Rez ◽  
Peter A. Crozier

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