Venting the SPLELEEM

1. Put the beamline in safe conditions

Check that all of the  valves are closed! It is important to close the manually operated CF 38 VAT valve between SPELEEM and the  i₀ chamber, so that mesh and photodiode can stay in static vacuum. Taking care of this saves a lot of outgassing after the bakeout!

2. Put the column in safe conditions

Close the Viton valve separating MCH and column. Do not tighten hard!
Switch off the channelplate and screen (firstly decrease the screen voltage to 2kV, then put MCP to 0, finally the screen to 0)
Slowly Turn the LaB₆ current to zero
Turn the microscope high voltage to 0.
Quit from UMeasure.
Set the electron analyzer supplies (i.e. Bias, sel+/-, ret lens, inner lens, accel. lens) to zero and their control to local.
In LEEM2000, select soft shutdown and start in the tools menu. Then quit LEEM2000. All lenses will slowly have their current set to zero. Quit Uview.
Switch off the HV power supply
Switch off the Lens Power supply

3. Put the main chamber chamber (MCH) in safe conditions

Switch off all filaments in the main chamber (ion gauges, evaporators, QMS); remove the water pipes.
Close tightly the VAT valve protecting the MCH ion pump.
Close the VAT valve separating the main chamber (MCH) from the large turbo.

4. Put the prep chamber in safe conditions

Check that the microscope foreline is pumped by the membrane pump and by the small turbo (Varian V70).
switch off all filaments: ion gun and ion gauge.
close tightly the VAT valve protecting the PCH ion pump.

5. Open the VAT valve separating PCH and MCH.
6. Open the elevator connecting the air-lock to MCH.
7. Stop the Varian V-70 (small turbo) and then its primary pump; vent with nitrogen.

Monitor carefully the pressure of the imaging column, because the MCH-COL valve may leak.

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