Table 1175. NanoMEGAS and its systems.
|
Notes/references |
NanoMEGAS |
Created in 2004 [1] |
Reciprocal cell |
Can be reconstructed automatically and precisely (error 2-5%) [1] |
Crystal cell parameters |
Can be
evaluated automatically and precisely (error 2-5%) [1] |
Beam size |
50 nm or less [1] |
Hardware |
DigiSTAR |
Diffraction mode |
Selected
Area Electron Diffraction (SAED), Nanobeam Electron Diffraction (NED), Pair Distribution Function(PDF) |
Diffraction intensity |
Quasi-kinematical
integrated intensities [1] |
Detectable reflections |
Enables the collection of higher-order reflections, which are more sensitive than lower-order reflections to small changes in lattice parameters [2] |
Rotation frequency |
~100 Hz [2] |
ASTAR |
Automatic crystallographic
indexing and orientation/phase mapping
tool for TEM |
The electron beam is scanned in
combination with beam precession through
the sample area of interest [1] |
Beam scanning
is done by the NanoMEGAS DigiSTAR
precession unit without using an inbuilt
STEM mode [1] |
A number of ED
(Electron Diffraction) patterns from several sample locations can be
acquired at high speed [1] |
Local crystal orientation(s) are
obtained by comparing all individually obtained ED spot patterns via cross-correlation matching techniques with pre-calculated ED templates [1] |
ADT3D software module |
Allows users to index
every reflection and to extract intensities useable
for structure analysis procedure [1] |
EDS and EELS measurements |
Beam Precession reduces channeling effects in EELS and EDS spectroscopy measurements |
[1] Advanced Tools For Electron Diffraction.
[2] A. D. Darbal, R. D. Narayan, C. Vartuli, G. Lian, R. Graham, F. Shaapur, S. Nicolopoulos and J. K. Weiss, Automated High Precision Strain Measurement Using Nanobeam Diffraction Coupled with Precession, Microsc. Microanal. 19 (Suppl 2), 2013.
|