Zeiss Crossbeam 550, Инструкция по эксплуатации

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6 Operation | 6.3 Modifying Gun Parameters ZEISS
6.3.2 Setting the Probe Current
Purpose With the GEMINI II 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.
Info
The maximum achievable probe current depends on the currently selected EHT and the in-
stalled aperture configuration.
1. In the Crossbeam SEM 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.
6.3.3 Measuring the Probe Current
Purpose Measuring the probe current using the Faraday cup ensures that the current displayed in the soft-
ware equals the incident probe current. The Faraday cup consists of a strongly absorbing material
with a cavity covered by a small aperture. If the beam is focused in this cavity, no secondary elec-
trons and no backscattered electrons leave the Faraday cup.
Parts and Tools
Designation Part no.
Faraday cup 348342-8055-000
1. Load the Faraday cup into the specimen chamber.
2. Evacuate the specimen chamber.
3. Switch on the gun.
4. Switch on the EHT.
5. From the Panel Configuration Bar, select Specimen Current Monitor.
à
The Specimen Current Monitor window is displayed.
6. Activate the Stage Bias checkbox.
à
This activates the touch alarm that helps to avoid collisions of the stage.
7. Move the stage to the position of the Faraday cup.
8. Acquire an image of the Faraday cup.
9. Activate the Spot checkbox.
à
Green crosshairs are displayed on the image. The crosshairs indicate the position of the
beam spot.
10. Grab the crosshairs and move them into the hole of the Faraday cup.
à
The probe current is measured continuously.
à
The measured probe current is displayed in the Specimen I readout.
80 Instruction Manual ZEISS Crossbeam 550L, Crossbeam 550 | en-US | Rev. 3 | 349500-8122-000