5 Commissioning and First Operating Steps | 5.5 Modifying Gun Parameters
ZEISS
Info
After switching the gun mode, you can immediately work with the selected gun mode. For ap-
plications, which require a high probe current stability, wait 24 hours until a stability of 0.2 %/
h is reached. It is recommended not to change the gun mode during quantitative specimen
analysis.
Procedure
1. From the
Menu Bar
, select
Tools > User Preferences
.
à
The
User Preferences
dialog is displayed.
2. Select
User > Expert Gun Mode
.
3. Click in the
Value
field and select
Yes
.
4. Close the
User Preferences
dialog.
5. In the
Panel Configuration Bar
, double-click GeminiSEM Control.
6. In the GeminiSEM Control panel, select the
Control
tab.
7. In the
Beam
section, click one of the following buttons:
To switch to Imaging gun mode, click
Imaging
.
To switch to Normal gun mode, click
Normal
.
To switch to Analytic gun mode, click
Analytic
.
INFO:
For maximum probe current, also check the alignment of the gun.
INFO:
If you use the Analytic gun mode, then the lifetime of the emitter is reduced.
5.5.2 Setting the Probe Current
With the Gemini 2 column, you can set a lower probe current to analyze surface details at a high
resolution or higher probe currents for analytical purposes, e.g. to analyze the material of the
specimen.
The
Optimum
probe current switches to a cross over free condenser setting and achieves the
highest resolution. This setting is effective for high magnifications.
Lower probe currents are suitable for beam sensitive samples.
Info
The lowest probe current can be achieved in
Imaging
gun mode.
For improved resolution,
Optimum
probe current and
Imaging
gun mode can be combined.
Info
The maximum achievable probe current depends on the currently selected EHT and the in-
stalled aperture configuration.
Procedure
1. In the GeminiSEM Control panel, select the Control tab.
2. Double-click the
I Probe
readout.
à
The
I Probe
window is displayed.
3. In the input field, enter the desired value.
5.5.3 Continuously Modifying the Probe Current (License: OPTIPROBE)
Info
OptiProbe allows you to continuously adjust the probe current. The function automatically se-
lects a suitable aperture and the current mode while the extractor voltage is adjusted to meet
the probe current selected by the user.
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Instruction Manual ZEISS GeminiSEM series | en-US | Rev. 2 | 349500-8138-000