ZEISS
6 Operation | 6.4 Working with Different Aperture Configurations and Beam Modes
6.3.4 Changing the Extractor Voltage
Purpose
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 II Column
Purpose
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 II column, two different column configurations are available:
§
40 nA high resolution configuration
Anode aperture diameter
Probe current
Typical application
55 μm*
10 pA to 40 nA
High resolution
§
100 nA high current configuration
Anode aperture diameter
Probe current
Typical application
90 μm*
10 pA to 100 nA
Combined high resolution
and analytical investigations
*
Calibration value: deviation of 10 % possible
Instruction Manual ZEISS Crossbeam 550L, Crossbeam 550 | en-US | Rev. 3 | 349500-8122-000
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Summary of Contents for Crossbeam 550
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