3 Product and Functional Description | 3.3 Optional Components and Accessories
ZEISS
1
Primary electron (PE) beam
2
Filtering grid
3
Beam booster
4
Magnetic lens
5
6
Backscattered electron paths
7
Specimen
8
InLens SE detector
9
Scan coils
10
Electrostatic lens
11
Retractable HDBSD detector
12
Interaction volume
HDAsB Detector
The HDAsB detector is an integral part of the objective lens and cannot be moved.
1
1
2
Fig. 44: Location of the
detector
1
Primary electron beam
2
Fixed HDAsB detector
3
Specimen
NOTICE
Collision between specimen and detector
The diodes can be damaged easily by contact with hard objects.
4
When you move the detector below the objective lens, make sure the specimen stage can-
not hit the semiconductors.
4
If you need to change the working distance, use the TV camera mode to view the speci-
men and help avoid a collision between the specimen and the detector.
Info
Risk of malfunction: The diode segments are sensitive to the light that is used for illumination
in TV mode (infrared and white).
When you use a diode detector, always make sure that the TV illumination is switched off. If
the CCD Mode is set to
Auto Detect
, then the TV illumination is automatically switched off
when a diode detector is used.
Position
Although BSE detectors can be used to image various types of specimen (crystal orientation con-
trast; magnetic contrast type II and so on), their main application is the display of material con-
trast (compositional differences). Their performance with respect to contrast is based on the
backscattering coefficient, which increases with increasing atomic number. A higher backscatter-
ing coefficient results in an increase in the number of backscattered electrons generated by the
primary electron beam, which are then made available for detection.
If different phases exist on the specimen, those with a higher average atomic number display
higher brightness than those with a small atomic number.
58
Instruction Manual ZEISS SIGMA series | en-US | Rev. 7 | 352102-9344-006
