Pumping and pressure reading

The pressure in the chambers should not exceed these values during the following operations:

Operation Analysis chamber Preparation chamber - bottom Preparation chamber - top Load lock Electrochemical cell
sample transfer 2×10-8 mbar 5×10-7 mbar 5×10-7 mbar 1×10-6 mbar 1×10-5 mbar
ion sputtering 2×10-6 mbar 2×10-6 mbar – – –
gas exposure 1×10-6 mbar 1×10-6 mbar 10 mbar – 1 bar
measurements 5×10-9 mbar – – – –


Simplified pumping and pressure measuring scheme (click for full version):
vacuum scheme

Analysis chamber

Turbomolecular pump

controlled by DCU in the right experimental rack
DCU  on/off on/off
  left or right browse parameters
  left together with right edit parameter and confirm
  Parameters:
  001: heating on/off
  012  venting on/off
  002: standby (slow speed) on/off
  309: actual rotation speed
  329: safety bearing wear
  358: rotor imbalance
  (manuals pump controller PDF)
Automatic venting when at ½ of nominal speed.
For venting connect nitrogen gas line to the venting valve.
Water- and air-cooled. Water cooling is necessary for bake-out.


Scroll pump

has no switch. Disconnect/connect the mains cable (orange).
For short periods you can just close the valve on the line below the turbopump and leave the scroll pump on.
(manual PDF)



Titanium sublimation pump

controlled by the bottom AML TSP2 controller In the left experimental rack.
TSP controller
knob off/continuous/degas/timed
(manuals pump controller PDF)


Cryopump

under the X-ray source, around the titanium sublimation pump
Helps removing water vapours from the residual gas.
For refilling with LN2 connect a hose with funnel (inlet) and another hose (outlet)
Refill approx. every 30 minutes.
After use blow out LN2 and humidity using compressed air for several hours. During thawing there will be high peaks on the pressure in the chamber (10-6 mbar) so do not do it during measurements!
You might run some titanium sublimation pump cycles in order to help the pressure recover.


Rotary vane pump

for pumping of the Θ rotary feedthroughs of the manipulators
It must be vented after switching off!
For short periods you can just close the valve on the line and leave the pump on.
(manual PDF)

Ionization gauge

controlled by Prevac MG15 controller in the left experimental rack.
ionization gauge controller  ionization gauge controller
Tap the Emis. button to switch the emission on/off.
Tap the pressure value to zoom it in.
Tap the pressure unit to change it.
The filament can burn at pressures above 10-4 mbar! Never switch on until the turbopump is at full speed and the cold-cathode gauge shows low pressure.
(manuals sensor controller PDF)


Cold cathode gauge 1

controlled by MaxiGauge controller in the left experimental rack, channel 1
  TPG366 channels switch channels
  up long press for switch on
  down long press for switch off
 
(manuals sensor controller PDF)




Cold cathode gauge 2

controlled by MaxiGauge controller in the left beamline rack, sensor 6.
TPG256A
Sensor choose sensor
Sen-on/Sen-off switch sensor on/off
(manuals sensor controller PDF)
This pressure can be monitored by Pressure Display software.


Pirani gauge

below the turbopump
Measuring the pressure in the roughing line (scroll pump)
TPG201






  (manual PDF)



Preparation chamber - bottom

Turbopumping station

containing membrane pump and turbopump.
Controlled by DCU in the right experimental rack.
DCU  on/off on/off
  left or right browse parameters
  left together with right edit parameter and confirm
  Parameters:
  001: heating on/off
  002: standby (slow speed) on/off
  309: actual rotation speed
  (manuals station turbo membrane controller PDF)
Automatic venting when at ½ of nominal speed.
For venting connect nitrogen gas line to the venting valve.
Water-cooled. Water cooling is necessary for bake-out.


Titanium sublimation pump

controlled by the top AML TSP2 controller In the left experimental rack.
TSP controller
knob off/continuous/degas/timed
(manuals pump controller PDF)


Cryopump

cryopump
Helps removing water vapours from the residual gas.
Refill with LN2 approx. every 60 minutes.
After use blow out LN2 and humidity using compressed air for several hours. During thawing there will be high peaks on the pressure in the chamber (10-6 mbar).

Cold cathode gauge

controlled by MaxiGauge controller in the left experimental rack, channel 3
  TPG366 channel switch channels
  up long press for switch on
  down long press for switch off
 
(manuals sensor controller PDF)






Preparation chamber - top

No turbomolecular pump

This chamber is pumped through preparation chamber - bottom (CF100 gate valve) or load lock (CF38 angle valve).


Cryopump

cryopump
Helps removing water vapours from the residual gas.
Refill with LN2 approx. every 60 minutes.
After use blow out LN2 and humidity using compressed air for several hours. During thawing there will be high peaks on the pressure in the chamber (10-6 mbar).


Rotary vane pump

for pumping of the Θ rotary feedthroughs of the manipulators
It must be vented after switching off!
For short periods you can just close the valve on the line and leave the pump on.
(manual PDF)

Full range gauge

controlled by MaxiGauge controller in the left experimental rack, channel 2
  TPG366 channel switch channels
  up long press for switch on
  down long press for switch off
 
(manuals sensor controller PDF)






Load lock

Turbopumping station

containing membrane pump and turbopump.
Controlled by DCU in the right experimental rack.
DCU  on/off on/off
  left or right browse parameters
  left together with right edit parameter and confirm
  Parameters:
  001: heating on/off
  002: standby (slow speed) on/off
  309: actual rotation speed
  (manuals station turbo membrane controller PDF)
Automatic venting when at ½ of nominal speed.
For venting connect nitrogen gas line to the venting valve.
Water- and air-cooled. Water cooling is necessary for bake-out.

Full range gauge

controlled by MaxiGauge controller in the left experimental rack, channel 4
  TPG366 channel switch channels
  up long press for switch on
  down long press for switch off
 
(manuals sensor controller PDF)






Electrochemical cell (UHV part)

Turbomolecular pump

controlled by DCU in the right experimental rack
DCU  on/off on/off
  left or right browse parameters
  left together with right edit parameter and confirm
  Parameters:
  002: standby (slow speed) on/off
  309: actual rotation speed

  (manuals pump controller PDF)
Manual venting valve.
Air-cooled. Be careful not to overheat the pump during bake-out because there is no water cooling!


Scroll pump

below the platform
scroll pump
For short periods you can just close the valve on the line below the turbopump and leave the scroll pump on.
(manual PDF)

 

Full range gauge

for UHV or air/nitrogen pressure measurements
Controlled by MaxiGauge controller in the left experimental rack, channel 5.
  TPG366 channel switch channels
  up long press for switch on
  down long press for switch off
 
(manuals sensor controller PDF)




Capacitance gauge

for argon pressure measurement
Displayed by MaxiGauge controller in the left beamline rack, channel 6. Always on.
TPG366  channel switch channels
  


(manuals sensor controller PDF)







Last Updated on Thursday, 19 October 2023 10:08