Scanning Electron Microscopy and X-Ray Microanalysis

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29


29.1.2 Polycrystalline Materials


Most crystalline materials are not single crystals. During
solidification from a molten state, numerous crystals

nucleate randomly in the liquid and grow in size until they
encounter each other, producing a three-dimensional
microstructure of randomly oriented crystalline units
called “grains.” Materials fabrication processes such as


[001]

5° 5 mm 5 mm

(220)

(110)

(400)

(100)







ab

. Fig. 29.3 a Wide field scanning (BSE image) of a Si single crystal
wafer whose surface is parallel to the (001) plane, thus looking along
the [001] pole; E 0 = 15 keV. b The traces of two different sets of crystal


planes are marked, as well as the parallel channeling bands defined
when the scan angle to the planes equals ± θB. Images processed with
ImageJ-Fiji CLAHE function

2° 1 mm 1° 500 μm

ab

. Fig. 29.4 a, b Progressively smaller scanning areas (higher magnifications) restrict the angular range and thus the portion of the electron
channeling pattern that is observed. Images processed with ImageJ-Fiji CLAHE function


Chapter 29 · Characterizing Crystalline Materials in the SEM
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