Metal Evaporation Instructions:

 

  1. Start with the Roughing(R) valve closed, the Foreline(F) valve closed, and the diffusion pump shut down.
  2. Open both the inlet and outlet valves on the wall for the chilled water flow to the diffusion pump.
  3. Turn on the mechanical pump, and open the F valve.
  4. Turn on the diffusion pump, first by enabling the roughing pump switch(listen for  an engaging clicking sound) and then press the diffusion pump power button.  Check to see that the diffusion pump is starting to warm up.
  5. Open the bell jar. (Remove the lead bar on top.  Open the nitrogen source valve on the right side of the evaporator.  Open the nitrogen vent valve on the left side of the evaporator.  Close it once the jar is open.
  6. Load samples, the materials to deposit, and check the electrical contact of the basket, boat or source.  Check the position of the shutter to ensure that it does not block the deposition.  (basket 1-4, boat 1-3).
  7. Close the bell jar, first cleaning the base cylinder and the gasket on the bottom of the bell jar.  Also clean underneath the base cylinder if necessary, and lightly grease the rim if needed.
  8. With F closed, open R, holding down the bell jar manually or with the lead weight.  Wait until TC2 reads ~100 mTorr (1.0E-1 Torr).
  9. Close R and open F. Wait until TC1 reads ~150 mTorr (1.5E-1 Torr).
  10. While waiting, get liquid nitrogen and connect it to the cold trap.  Turn on the cryomiser by flipping the switch to “Auto”.  If the nitrogen pressure is initially below 5, open the valve to supply nitrogen to bring it up to a 10-15 psi level.  Turn off the valve after that to avoid overpressure.
  11. Wait until the cold trap box is filled, and the solenoid switch goes off.
  12. Check TC1 and TC2 pressures.  If OK then turn the Hi-Vac crank valve all the way counterclockwise.
  13. Wait about an hour until the chamber pressure comes down to ~E-6 Torr.  Check this with the ion gauge by pressing the “emis” button.  Wait for it to heat before reading the pressure.
  14. Program the crystal monitor:
    1. Press “PG”
    2. Enter the density, z-ratio, tooling factor, thickness limit, and final thickness.  Thicknesses are in KA.  Tooling factor is normally 130%.  For Al, r = 2.70, z-ratio = 1.08, thickness limit should be just a bit higher than the final thickness.
    3. Cr: r = 7.20, z-ratio = 0.305
    4. Au: r = 19.3, z-ratio = 0.381
    5. Press “PG”
  15. Turn filament on.
  16. Apply voltage slowly, avoiding the max fuse current of 15A.
  17. Hit the Start button and check the monitor.  Hit Stop, Zero, and Start on the crystal monitor controller and open the shutter.
  18. Close the shutter when the monitor shows thickness has reached desired value.
  19. Cut the power, turn off the filament, and the crystal monitor.
  20. Close the Hi-Vac valve, turning fully clockwise.  Turn off the Cryomiser, and the ion gauge.
  21. Open the bell jar, unload samples, and clean the window.
  22. Close the bell jar.  Close F and open R.  Wait until TC1 reads 150 mTorr.
  23. Close R and open F.  Turn off TC gauge.  Wait until the cold trap box completely warms up to room temp, and then turn off the diffusion pump.
  24. Close both the inlet and outlet valves on the wall for the chilled water flow to the diffusion pump.  Close F and turn off the mechanical pump.  Confirm system is shutdown.