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last update 15/02/2010
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 Microscope procedures 

Operating procedures
Sample transfer
Microscope Alignment Procedure
LEEM operation mode
XPEEM operation mode
Diffraction operation mode
Dispersive plane mode 		  Maintenance
Venting
Pump down
Preparing a bake-out
Outgassing after bake-out
Channelplate HV ramping
SPELEEM analyser HV ramping
Prep chamber manipultor wiring

OUTGASSING PROCEDURE AFTER BAKE-OUT

Before switching off the bake-out!
  • Switch immediately on ion pumps in MCH and PCH; you might need to wait until they stop outgassing
  • The out-gassing procedure is effective when pumping the MCH with the MCH turbo pump; therefore, please keep the gate valve to MCH turbo OPEN until the procedure is completed.
  • Ion gauges: set emission current to 4.00 mA (push F/emis mA in the Multigauge board).
  • Keep the Variac ON (180 V) during the entire outgassing procedure.
Now, switch off the bake out!

140°C

MCH must quiclky reach the eights eights. Switch off the ion pump and degas the ion gauges. MCH, COL, and PCH degas (10 min). Note that during degas the chamber pressure cannot be read.

130°C

Degas TSPs:

  • MCH (controller on the left hand side): use filament only; 2.7 A, 10 min.
  • PCH (controller on the left hand side): filament and HV to 50mA emis for 15 min.

120°C

  • Remove the outer tent, leave the inner, to facilitate cooling. When doing this, watch out for the microscope aperture linear motion feedthoughs and the gas line bottles.

  • Au evaporator controller (ELMITEC): set the filament current to 2.0 A, high voltage 0 V and check that the temperature regulation is off. After some time T should reach 500˚C (do not worry, the TC is on the crucible and not well calibrated).

  • Start up the microscope HV rack. Check that all of the electron analyser modules (i.e. bias, SEL+/-, retarding lens, inner lens, accel. lens) are set to local, with their knobs turned to zero (fully anticlockwise). Then, switch on the high voltage power supply (big green button). In order to degas sample and objective, set sample filament to 2.0 A (dia. is 0.125 mm), bombardment voltage to 10V (emission current should be negligible). After some time, the sample temperature will reach about 7 mV. Note that the rack cannot be switched on if the bake out controller is still on.

100°C

Degas TSPs:

  • MCH (controller on the left hand side): use filament only; 2.7 A, 5 min.
  • PCH (controller on the left hand side): filament and HV to 90mA emis for 5 min.

95°C - REMOVE THE INNER TENT

Main chamber:

  • Connect the FOCUS controller (in in stand-by or off) to the Omicron evaporators. Try to degas evaporators simultaneously. Bring I fil to 1.8 A, HV = 0 and set T shroud, so that it can not exceed 300˚C (the controller will switch off when T shroud = 300˚C, over-temperature, so the procedure is safe). Once at 290˚C, set I filament to 0.5 A, wait until T shroud decreases to 220˚C, then raise the filament to 1.80 A so that T can reach 290˚C again. Degas evaporators for about 2-3 hours.
  • Degas other evaporators (if present) Notice that it may be better to retract the sample manipulator, in order to prevent the sample from being contaminated.
  • Alkali dispencers (SAES getters): check out on the saesgetters web site (http://www.saesgetters.com/prdfr_amd.htm) and take care not to exceed the recommended activation current (4.5A).
  • Degas sample cartridge (and thus objective lens): filament to 2.2A, bombardmentvoltage 200V (if sample allows it, do not do this with Si wafers), I emission 15 mA; T sample should reach ca. 10 mV.
  • QMS: run Programs/spectra/RGA on pnanoX. Then switch on filament one, and in the filament menu select Degas ion source. NEVER EVER operate the multiplier if T > 50˚C and the total pressure is above the 10-7 torr range (2∙10-6 torr max)!!!! This may cause serious damage to the multiplier.

Prep chamber

  • Connect the the cable to the ion gin feedthrough using extreme care, as the cable may exert a torque on the glass feedthrough, which is extremely delicate. When inserting the plug in the feedthrough, firmly hold the cable so that it does not rotate and release it only after the plus has been locked. Switch on the gun control unit (981-2046). In order to reset the DEGAS timer, always select the operate mode before switching to degas.
  • Prep chamber manipulator: degas the sample cartridge (if a suitable sample was inserted!) and surroundings by setting the filament current to 2.2 A. Only with Mo dummy or W(110) sample use 200 V.

60°C

Variac to 0 V.

Switch the turbo heater off if this was on (select parameter "001" with the arrow keys. In order to change the parameter value push "<" and ">" simultaneously. Set "heating" to off with "<"" and confirm by re-pushing "<"" and ">" simultaneously).

Before leaving ....

It is now time to switch everything off (Elmitec evaporators, Omicron, Sample heater).

Fire the PCH TSPs once more (5 mins, 105 mA).

Go home and have some fun because this procedure is quite boring!