Zeiss EVO - Switching on the Gun | Lab₆ Filament; Switching on the EHT | Lab₆ Filament

5 First Operating Steps | 5.4 Acquiring an Image ZEISS
5.4.4 Switching on the Gun | LaB₆ Filament
Info
If you operate the microscope with a LaB₆ filament, then you need to switch on or switch off
the gun and the EHT separately.
Prerequisite
ü
The chamber and the gun head have been evacuated.
Procedure
1. In the right part of the Status Bar, verify whether the gun is switched on or off.
à If
or is displayed, the gun is already switched on and you can skip the fol-
lowing steps.
à If
is displayed, the gun is switched off.
2. In the SEM Controls panel, select the Vacuum tab.
3. Verify that the EHT Vac ready readout is EHT Vac ready = Yes.
If not, the correct vacuum is not achieved. Check if the Pump procedure has been com-
pleted.
4. In the right part of the Status Bar, click
.
à The pop-up menu for vacuum, gun and EHT activation is displayed.
5. Click Beam On.
à The gun runs up.
5.4.5 Switching on the EHT | LaB₆ Filament
When you switch on the EHT, the gun starts emitting electrons.
Info
If you operate the microscope with a LaB₆ filament, then you need to switch on or switch off
the gun and the EHT separately.
Prerequisite
ü
The chamber and the gun head have been evacuated.
ü
The gun has been switched on.
Procedure
1. In the SEM Controls panel, select the Vacuum tab.
2. Check that Vac Status = Ready is displayed.
3. In the SEM Controls panel, select the Gun tab.
4. Double-click the Fil I Target readout.
à The Fil I Target window is displayed.
5. In the input field, enter the required filament current in mA and click OK.
INFO: For a LaB₆ filament, you may start with a filament current of approximately
1800mA.
6. In the SEM Controls panel, select the Gun tab.
7. Double-click the EHT Target readout.
à The EHT Target window is displayed.
8. In the input field, enter the required acceleration voltage in kV and click OK.
9. In the right part of the Status Bar, click
.
à The pop-up menu for vacuum, gun and EHT activation is displayed.
10. Click EHT On.
à The EHT runs up to the set voltage.
68 Instruction Manual ZEISS EVO | en-US | Rev. 10 | 354706-0780-006