ZEISS
3 Product and Functional Description | 3.2 Main Components
3.2 Main Components
3.2.1 Vacuum System
Purpose
For operation of the microscope, the gun head, the column, and the specimen chamber have to
be evacuated. The vacuum is essential to operate the gun and to prevent collisions of electrons
with gas molecules.
1
2
3
4
5
8
9
10
6
7
Fig. 8: Schematics of the vacuum system of a microscope with Gemini II column
1
Gun with filament
2
Gun head
3
Single hole aperture
4
Column chamber valve
5
Turbo pump
6
Ion getter pumps (IGP)
7
Specimen chamber
8
9
Vent valve
10
Operating
Principle
System Vacuum
The pre-vacuum pump
10
and the turbo pump
5
evacuate the specimen chamber
7
.
The vacuum in the specimen chamber is measured by a Penning gauge
8
. The detected vac-
uum values are displayed as System vacuum in the SmartSEM user interface. As long as the de-
tected pressure in the specimen chamber is not ready for operation, the column chamber valve
4
is closed in order to separate the specimen chamber from the column.
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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