Trends in BKD / Automated EBSD
 

The Scanning Electron Microscope (SEM)

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Clean vacuum  ==> less contamination

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Variable Pressure SEM  ==> no charging, no contamination

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Schottky Field Emission ==> high beam brightness

· High current in small probes ==> improved spatial resolution
   (but be aware of damaging the specimen and increased contamination rate)

· Small beam aperture  ==>  large depth of focus

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Adequate camera port
(wide, perpendicular to x-y stage movement, low position)

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External computer control, computer interface

The Acquisition System

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A digital CCD camera vs. analog video camera:

· fast: ~ 750 frames/sec and more with a GigE Vision CCD camera
           vs. 25 video frames/sec resp. 15 frames/sec with VideoforWindows

· high sensitivity by pixel binning on the chip.

· high dynamics (12-14 bit), no flat image for background correction required.

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Lensless direct exposure of the sensor chip (high quantum efficiency, low beam voltage).

 

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