ZEISS
3 Product and Functional Description | 3.2 Main Components
3.2.4.4 SE Detector
Purpose
The SE detector is an Everhart-Thornley type detector. It detects SEs as well as BSEs.
Position
The SE detector is attached to the options ports plate.
1
2
4
5
3
6
Fig. 13: Schematics of the
1
Preamplifier
2
Photomultiplier
3
Light guide
4
Scintillator
5
Collector grid
6
Specimen
Operating
Principle
Electrons moving to the detector are attracted/repelled by the collector grid and directed to the
scintillator. The electrons gain energy from the scintillator and thus are able to interact with a
phosphor layer, which generates photons (light). The light travels up a light pipe to a photomulti-
plier. The photomultiplier multiplies the flashes of light and outputs a signal that can be used for
imaging.
The collector voltage can be varied in the range between −250 V and +400 V.
A positive collector voltage generates an electrical field in front of the detector, thus directing the
low energy SEs towards the scintillator.
Info
For all standard applications, the collector bias should be set to +300 V.
Instruction Manual ZEISS Crossbeam 350 | en-US | Rev. 3 | 349500-8111-000
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