System control: Vacuum system
2-9
C O N F I D E N T I A L
– limited rights
User Manual
Revision A
Feb 2018
Vacuum system
Model difference
There are the High Vacuum and Low Vacuum variations of the
Apreo system. This manual describes the Low Vacuum model.
For the High Vacuum model, some controls are missing and
functionality is modified accordingly.
The system has the these vacuum sections:
•
Electron source
•
Electron column
•
Specimen chamber
When in operation, the electron source and column section are
always under high vacuum. The specimen chamber is at the
pressure required for the given state (Pump / Vent) or mode
(HiVac / LoVac).
Note
When the LoVac mode is chosen, the ChIV is closed. All valve and
pump operations are fully automatic.
FIGURE 2-4:
Apreo high vacuum / Apreo low vacuum Vacuum system
AGV
. . . . . . Auxiliary Gass Valve
BPV
. . . . . . . By Pass Valve
BG
. . . . . . . . Buffer Gauge
BV
. . . . . . . . Buffer Valve
CIV
. . . . . . . Column Isolation Valve
ChEV
. . . . . . Chamber Evacuation Valve
ChIV
. . . . . . Chamber Isolation Valve
EG
. . . . . . . . Environment Gauge
HVG
. . . . . . High Vacuum Gauge
IGP
. . . . . . . .Ion Getter Pump
NAV
. . . . . . .Nitrogen Admittance Valve
NVC
. . . . . . .Needle Valve Control
PVP
. . . . . . .Pre Vacuum Pump
SIV
. . . . . . . .Servo Isolation Valve
TMP
. . . . . . .Turbo Molecular Pump
TVV
. . . . . . .Turbo Venting Valve
VV
. . . . . . . .Venting Valve
WBV
. . . . . .Water Bottle Valve