Zeiss GeminiSEM Series, Инструкция по эксплуатации

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5 Commissioning and First Operating Steps | 5.8 Working with Variable Pressure ZEISS
Mode Beamsleave aper-
ture Booster Chamber Pressure
High Vacuum HV None On < 10⁻² Pa
Standard VP None Off 5–60 Pa
Nano VP 800 µm
350 µm
On
On
5–40 Pa
5–150 Pa
XVP 800 µm
350 µm
Off
Off
5–150 Pa
5–500 Pa
Tab. 3: VP configuration
5.8.1 Changing to Standard VP Mode
Info
If the VP system has not been used for several days, start with moderate pressure up to 30 Pa
for the first 10 minutes.
Afterwards the vacuum system is conditioned and the VP mode can be used with its full range.
Info
A higher pressure can be set within a few seconds. Achieving a lower pressure may require
some more time, because the specimen chamber has to be evacuated by the pre-vacuum
pump.
Prerequisite ü The microscope is operating in HV vacuum mode
Procedure
1. In the GeminiSEM Control panel, select the Control tab.
2. In the
Variable Pressure section, click VP .
à
The acceleration voltage decreases to zero, the column chamber vale and the Turbo iso-
lation valve close, the Roughing backing valve and the Gas flow valve open.
à The pressure in the specimen chamber is increased until the selected value is reached.
à
The system sets the chamber pressure to the value displayed in the VP Target field. If
you have not changed it, it is the value of the last VP session.
à
The transition is indicated in the status bar of the SmartSEM software.
à
The acceleration voltage is activated and the column chamber valve opens.
3. Wait until the system is ready for VP operation and Chamber Status = At VP is displayed.
à
This takes approximately 30 s.
4. To change the chamber pressure, use the VP Target scroll bar.
Alternatively double-click into the VP Target field, enter desired pressure value and click
OK .
Refer to Working with Variable Pressure [
}
103] to determine the correct pressure value.
104 Instruction Manual ZEISS GeminiSEM series | en-US | Rev. 2 | 349500-8138-000