BECM

Post Bake Out

POST BAKE OUT

 

  • HT Conditioning/restart/cooling
  • GunAlignment

Cooling and conditioning after bake out

  1. Start refilling of both Liquid nitrogen tanks by clicking “Auto” in the “LN2 Auto Refill Maintenance window” for “transfer tank” and “stage tank”.
  2. In TEM center on the microscope pictogram click on “HT”.
  3. In the operation for “Conditioning Rod” click on “Condition”.
  4. Once the rod is in position (pink progress bar), click in the line “HT” the button “ON”
  5. Wait until procedure is finished (~55 minutes).
  6. If you realize that one of the nitrogen tanks gets refilled start manually also the refill of the second tank by clicking “Refill” in the “LN2 Auto Refill Maintenance” window.
  7. Once finished HT will be back to 0 kV.
  8. Switch the “conditioning Rod” back to “Operate”.
  9. Click on “HT” the button “ON”
  10. Wait until procedure is finished (~25 minutes).
  11. close HT window
  12. In the microscope pictogram hover over “Emission” and click on “Flashing” the button “High”.
  13. When done click in the same window on “Auto Emission” “ON”.
  14. Emission will ramp up to 10 uA.

 

Gun Alignment

DO NOT DO THIS EVEN AS A USER OR SUPERUSER!!!

  1. Open the beam valve
  2. Switch off Low Dose mode in SerialEM (if it is on).
  3. Go to Spot size 1.
  4. Set Beam Align 1 to Default.
  5. Go to 10k or 20k Magnification
  6. Set exposure time on large phosphor screen to 0.001s (minimum)
  7. Remove CL aperture.
  8. Condense beam.
  9. Center beam with GunAlign 1. Focus on the bright spot as center.
  10. Switch on Anode wobbler.
  11. Make beam concentric between the changes using GunAlign2. (Spreading in all direction equivalently).
  12. Repeat GunAlign1 and Anode wobbler until you do not have to reposition GunAlign1 anymore.
  13. Go to the Spot size you will be working with (i.e. 6)
  14. Go to 60k Magnification.
  15. Insert CL aperture.
  16. Set exposure time on large phosphor screen to 0.02 s.
  17. Switch on Anode wobbler.
  18. Adjust GunAlign2 so that the beam is concentric between the changes.
  19. Control the concentricity with CL aperture removed (Above procedure only works well if CL aperture is centered). Adjust GunAlign2 if necessary.