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6 Operation | 6.4 Working with Different Aperture Configurations and Beam Modes
ZEISS
6.3.3 Changing the Extractor Voltage
The Extractor voltage is preset by the factory or by the ZEISS service representative. Within certain
limits, the operator may carefully increase the extractor voltage in order to optimize the probe
current for particular applications.
Info
Use a Faraday cup to measure the probe current when changing the extractor voltage.
Info
The newly set extractor value is only valid for the current work session. After a restart of the
SmartSEM software, the microscope restores the nominal extractor voltage.
Info
Reducing the extractor voltage may impair the performance and resolution of the microscope.
§
Avoid reducing the extractor voltage.
§
If at all, reduce the extractor voltage only for a short time (1–2 h) and by maximum 500 V.
Prerequisite
ü
The user privilege
Extractor
is required to change the extractor voltage.
1. From the
Menu Bar
, select
Beam > Gun Setup
.
à
The
Gun Service
dialog is displayed.
2. To increase the extractor voltage, double-click the
Extractor V Target
readout.
à
The
Extractor V Target
window is displayed.
3. Enter a higher value.
4. Click
OK
.
6.4 Working with Different Aperture Configurations and Beam Modes
6.4.1 Determining the Installed Aperture Configuration | Gemini I Column
The achievable maximum probe current depends on the type of installed anode aperture. The
type of aperture installed on the microscope can be determined via SmartSEM.
For the Gemini I column, two different column configurations are available:
§
20 nA high resolution configuration
Anode aperture diameter
Probe current
Typical application
40 μm
5 pA to 20 nA
High resolution
§
100 nA high current configuration
Anode aperture diameter
Probe current
Typical application
90 μm
12 pA to 100 nA
Combined high resolution
and analytical investigations
*
Calibration value: deviation of 10 % possible
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Instruction Manual ZEISS Crossbeam 350 | en-US | Rev. 3 | 349500-8111-000