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JEOL 4000EX High Resolution Electron Microscope (HREM) 400kV

Alignment Procedure

Check that the objective and selected area apertures are out.

Check the vacuum: IGP1: 5.4 x 10^-5  black scale (max 7 x 10^–5)

 IGP2: 0.8 x  10^-5  black scale (max 3 x 10^–5)

Check that the green READY light is lit and BRIT TILT button is lit.

1. HT should be on at 350 KV; turn on at 300 KV, if not on, and step up to 350 in 1 KV steps.
2. Step up KV to 400, 1 KV at a time.
3. Open AIR LOCK. Wait for green filament light.
4. Increase Filament temperature SLOWLY, let it sit @ 4.5 for 20 min, then increase the BEAM CURRENT 0.1 mA at a time. Saturate the filament, usually found at the silver anchor; it may vary. Filament image should be visible and symmetrical. Adjust with GUN DEFs if not symmetrical.
5. Slowly converge the beam with BRIGHTNESS, and center with SHIFTS.
6. At spot size 1 and 25KX, center the converged beam with GUN SHIFT.
7. Increase the spot size to 5, converge the beam and center with SHIFT.
8. Repeat centering at spot size 1 (GUN SHIFT), then spot size 5 (SHIFT), to center gun with condenser lens.
9. Choose spot size 2.
10. Correct astigmatism with the COND STIGMATOR DEFLECTOR.
11. Turn down the filament; close AIR LOCK.
12. Check that specimen drives are at 0,0. Insert sample into column:
• Exchange mechanism lever on O, for open.
• DOWN, to specimen holder.
• GRAB (unlabelled knob)
• UP
• IN
• DOWN
• RELEASE (unlabelled knob)
• UP
• OUT
• Exchange mechanism lever to P, for pump.
13. Open AIR LOCK, increase filament temperature, SLOWLY.
14. Set OBJ lens current to focus (@400 KV = 6.65)
15. Adjust z-axis for minimum contrast.
16. Increase mag to 200K X and correct for HT wobble (BRIT TILT DEF). If wobble is gross, start at a lower mag.
17. In the DIFF mode, insert the objective aperture, center it around the illumination.
18. At 200K X or more, correct for objective astigmatism (OBJ STIG DEF).

SHUT DOWN

1. Turn off the FILAMENT, slowly.
2. Close the AIR LOCK.
3. Check that specimen drives are at 0,0. Remove the sample from the column:
• Exchange mechanism lever on O, for open.
• Wait for green SPEC light.
• IN
• DOWN
• GRAB (unlabelled knob)
• UP
• OUT
• DOWN, to specimen holder.
• RELEASE (unlabelled knob)
• UP
• Exchange mechanism lever to P, for pump.
4. Leave HT on and KV at 350.
5. Log in the state of the microscope as it was left.

TO REMOVE FILM:

          Wear gloves !

1. Retrieve the empty plate holder box from the desiccator or the darkroom; a dark bag should be with it, to transport the exposed negatives across the lighted hallway.
2. Turn on dry nitrogen at the tank.
3. Turn the handle on the front of the camera door clockwise 90^o.
4. Turn out the room light.
5. Wait for the camera door to pop open.
6. Pull out the drawer containing the film boxes, by the handle.
7. The first box contains exposed film (to be developed), remove it from the drawer, put the box in the dark bag.
8. If the FILM box has less than 10 pieces of film, replace it with a fresh box  from the desiccator.
9. Close the camera door securely: it will require a strong push.
10. Turn the handle on the door counterclockwise 90 ^o; the vacuum system should be audibly pulling on the camera chamber.
11. Turn off the dry nitrogen tank.
12. Take both boxes to the darkroom: either refill the FILM box with fresh film, or tell someone who knows how to fill it that it needs to be done.

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