XeF2 Instructions

Always use gloves and a respirator when working with XeF2. 

Do not expose XeF2 to moisture.

 

Things to turn on in the Service Corridor:

  1. Nitrogen
  2. XeF2 vacuum pump

Things to turn on at the machine:

  1. Nitrogen Turret
  2. Local Vacuum Turret

Inserting a sample

  1. Check that all valves are closed
  2. Turn on the pump (orange) and the N2 tank and set N2 pressure to 5psi
  3. Remove the clamp from the front plate, open the N2 valve
  4. The front plate will slide off once the pressure equalizes
  5. Insert the sample
  6. Replace the front plate and close the N2 valve
  7. Replace the clamp on the front plate
  8. Open the pump valve
  9. Wait 30 seconds then turn on the DMM and pressure sensor
  10. Wait until the pressure goes as low as possible (<200mTorr*) this will be the minimum pressure

Etching

  1. Open the pump valve

  2. Wait until the pressure reaches the minimum (about 1 minute)

  3. Close the pump valve

  4. Open the XeF2 valve

  5. Wait 30 seconds *

  6. Close the XeF2 valve

  7. Wait 1 minute

  8. Repeat all steps as necessary

Removing a sample

  1. Open the pump valve (with all other valves closed)
  2. Wait until the pressure reaches the minimum (<200mTorr)
  3. Open the N2 valve
  4. Wait 5 minutes
  5. Remove the clamp from the front plate
  6. Close the pump valve
  7. The front plate will slide off once the pressure equalizes
  8. Remove the sample
  9. Replace the front plate and close the N2 valve
  10. Replace the clamp on the front plate
  11. Open the pump valve
  12. Wait 30 seconds then turn on the DMM and pressure sensor
  13. Wait until the pressure goes as low as possible (<200mTorr)
  14. Turn everything off 

*if the pressure does not increase to >1.5mTorr within 5 seconds add XeF2 crystals

Adding XeF2 crystals

  1. Always use gloves and a respirator
  2. Minimize the exposure of XeF2 crystals to air
  3. Obtain the following, spatula, Teflon tape, plastic Petri dish
  4. Remove the XeF2 crystals from the acid cabinet (double bottled)
  5. Place the plastic Petri dish under the chamber in case of a spill.
  6. Unscrew the top from the XeF2 chamber, remove old Teflon tape, replace with new teflon tape, set cap on top of the chamber but do not screw on.
  7. Remove the inner XeF2 bottle from the outer bottle keeping chamber and bottle exposed to air for the least amount of time possible, scoop 10-12 crystals from the bottle, set the cap on the bottle, pick up chamber top, place crystals in the chamber, close the XeF2 chamber. 
  8. Purge the XeF2 stock bottle with N2 gas to remove air before closing.
     

procedure prepared by Francisco Tejada, Spring 2003; modified by La Vida Cooper, Spring 2003.