JEOL JSM-6390 LA, Руководство пользователя

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SEM manual ETHZ v1.4
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K.2) Treating element or phase maps
K.2.1) Extracting “Element maps”
To extract element maps (see Fig. 27 ):
1. Select your Spectral Imaging acquisition (under “Base Name”).
2. Mark the element as “Always identified” to force the identification of an element even
if the software does not think it is present. Remember that if you have loaded some
standards, the associated standard elements will be marked as “Always identified”.
3. Select the tab “Processing” (bottom-left panel) to change the map treatment options:
•
Leave the first options active (“as is”): removal of sum peaks & escape
peaks, automatic element identification, quantification (pending you are using
standard, otherwise it is only “semi-quantitative”), and element map extraction.
•
You may change the data to be displayed : counts, net counts, atomic, etc.
•
You may opt for a Kernel size larger than 1x1 (= pixel averaging). This is
recommended to smooth a map that would be too noisy (low counts per pixel).
•
You may change the “Quant map detail” and “Filter fit type” to a higher
quality setting (to the cost of an increase in processing time).
4. To extract the images, press the “Export Map Images” button and wait for the
completion of the data processing. Depending on the mapped area and the selected
processing options, it can take a few minutes.
5. See Section K.3 for additional options once the maps are extracted.
K.2.2) Extracting “Phase maps”
To extract phase maps (see Fig. 28 ):
1. Activate first the “COMPASS” mode and choose either…
a) “Components” to show the principal component analysis (PCA);
b) “Phases” to show the phase analysis (what truly interests you…).
2. Press the “Extract Map Images” button to show either the PCA or the phase maps.
The processing may take a few minutes depending on the processing options
selected (see
Section K.2.1 , point 3).
K.2.3) Extracting and quantifying a “Spectrum” from of an element map
To extract a spectrum, for instance, in order to properly identify a phase (see Fig. 29 ):
1. Activate the “Rectangle” option . A yellow rectangle should appear on the BSE
base image (top-left panel).
2. Move & resize the rectangle over a homogeneous and well-polished area of interest.
3. The sum of all ED spectra from the selected pixels is shown as an “Extracted
Spectrum” in the bottom-right panel, and it should ease you phase identification.
4. OPTIONAL: If you want to save this extracted spectrum as a single EMSA file…
a) Select the analysis mode “Spectrum”.
b) The extracted spectrum will be called in this mode.
c) Select menu “File > Save as…” and save the spectrum as an EMSA file.
d) You can also quantify this spectrum (providing you are using standards) as
you would quantify a point analysis (in “Spectrum” or “Point & Shoot” mode).
Be careful, the analytical precision is likely to be poor as there are very low
counts on each pixel, even after pixel-averaging, unless you have hundreds of
pixels included!