ZEISS
3 Product and Functional Description | 3.3 Optional Components and Accessories
3.3.1.9 AsB Detector
Purpose
The Angular selective Backscattered (AsB) detector is completely integrated into the pole piece of
the Gemini lens. This allows you to image BSEs with ultra short working distance.
The AsB detector is available either with one video output channel or with four video output
channels. Imaging with the AsB4 detector is especially useful for 3D surface reconstructions using
the optional 3DSM software. Please refer to Software Manual 3DSM.
The AsB detector can be configured and used in VP configuration, but not if NanoVP is config-
ured. As the AsB detector is integrated in the pole piece, it is not compatible with the beamsleeve
used in NanoVP/XVP mode.
1
2
3
4
Fig. 34: Schematics of the
1
InLens SE detector
2
Objective lens
3
AsB detector
4
Specimen
Function
High angle BSEs carrying an energy close to the landing energy of the primary beam, are pro-
jected into the Gemini column as well. If the angle is too low the BSEs will not enter the column
but will land on the objective lens
2
pole piece, where they can be detected by the integrated
AsB detector.
The AsB detector is equipped with four diodes, which can be controlled independently via a
menu. Compositional mode images show the atomic contrast of the specimen
4
, whereas to-
pography mode images show surface details.
Info
BSE imaging is only possible at acceleration voltages above 1.5 kV.
Instruction Manual ZEISS GeminiSEM series | en-US | Rev. 2 | 349500-8138-000
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