ZEISS
3 Product and Functional Description | 3.3 Optional Components and Accessories
3.3.1.3 EsB Detector
Purpose
The Energy-selective Backscattered (EsB) detector enables both SE and BSE detection. It can be
used for high contrast topography or for compositional contrast examinations.
The SEs and BSEs generated at the impact point of the primary electron beam are intercepted by
the low electrical field of the column. These electrons are accelerated by the field of the electro-
static lens.
Position
The annular shaped in-column detector is located above the InLens SE detector.
1
3
2
1
3
2
Fig. 20: Schematics.
EsB
detector
(right)
1
EsB detector
2
Filtering grid
3
Operating
Principle
A small amount of SEs pass through the hole of the InLens SE detector
3
and would be ob-
served by the EsB detector
1
. To prevent detection of these SEs, a filtering grid
2
is in-
stalled in front of the EsB detector. By switching on the filtering grid voltage, the SEs are rejected
and only BSEs are detected.
Below a landing energy of 1.5 kV, the filtering grid
2
has the additional function of selecting
the desired energy of the BSEs. The operator can select the threshold energy of inelastically scat-
tered BSEs to enhance contrast and resolution.
The combination of InLens SE detector
3
and EsB detector
1
allows simultaneous imaging
and mixing of a high contrast topography (SE) and a compositional contrast (BSE).
Instruction Manual ZEISS Crossbeam 350 | en-US | Rev. 3 | 349500-8111-000
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