Tag Archives: 660 scanning auger

660 System up to air procedure

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Overview

This procedure will allow you to safely bring the 660 scanning auger system up to air for maintenance.

 

  1. Shut down AugerMap and turn off the 20-610 electron gun control (filament down slowly) Also turn off the 20-622 gun control.
  2. Turn off the card rack power
  3. If V4 is open, close it by pressing the Diff Pump Ion Gun button on the AVC remote.
  4. Pump the intro.
  5. Turn off the DIGIII ion gauge.
  6. Turn off the Ion pump control and Boostivac control.
  7. Allow the system to cool for at least 30 minutes. (Or just a few minutes if the electron gun was not on.)
  8. Make sure that the turbo pump is on. If you have more than one turbo pump, they both need to be on.
  9. With the turbo pump on and the intro still being pumped, depress the Backfill Chamber button on the Auto Valve control located behind the vacuum console.
  10. You will hear a hissing sound as air is back-filled into the chamber.
  11. Slightly loosen the intro hatch cover so that when the system is pressurized it will open.
  12. Once the system is vented, turn OFF the turbo pump(s).

 

 

660 System Pump Down procedure

Overview

This procedure will allow you to safely pump down the system after being up to air for maintenance.

 

  1. Make sure that all flanges are secured (use new copper gaskets whenever removing and replacing optics on the vacuum chamber).
  2. With the turbo pump(s) off, depress the Rough Chamber button on the Auto Valve control located behind the vacuum console.
  3. Make sure that the intro hatch is closed.
  4. Turn on the turbo pump(s) by depressing the pumping unit button. You will hear the V2 valve close and the V3 and V4 valves open and the turbo(s) will begin to pump the system out.
  5. After about 20 minutes you should have 5 bars on the Auto Valve control remote. Once you have 5 bars, cycle each of the 4 titanium sublimation filaments for about 2 minutes each at 50 amps on the Boostivac control.
  6. Cycle each filament 2 times, with a few minutes of cool down time between filaments.
  7. After all 4 filaments have been out-gassed, make sure that you still have 5 bars on the Auto valve control remote and then turn on the DIGIII by turning the power switch to UHV and depressing the I/T 3 button.
  8. The DIGIII should indicate in the low 10-3 to mid 10-4 range. Allow the turbo to pump until the system pressure is in the low 10-4 to high 10-5 range, about 30 additional minutes.
  9. Cycle the #1 titanium sublimation filament for about 2 minutes at 50 amps. (Note: If a TSP filament can no longer get at least 45 amps, use the next filament).
  10. When the vacuum is in the low 10-5 range, start the ion pump control by turning the Mode switch to Start. Monitor the 10KV scale. The voltage should be increasing (maximum is about 5.5 kV), and the DIGIII should indicate that the vacuum is dropping into the 10-6 range.  (Note that the meter on the Boostivac does not always read, if not then just make sure that you are in the 10-6 range and dropping on the ion gauge).
  11. Once the DIGIII indicates the high 10-6 range, close the V1 valve by depressing the Rough Chamber button on the Auto Valve control located behind the vacuum console one more time. You will hear the V1, V3 and V4 valves close.
  12. On the Auto valve control remote, depress the Diff Pump Ion Gun button to differentially pump the ion gun.
  13. The system vacuum will continue to improve over the next few hours. Cycle the #1 titanium sublimation filament every 30 to 45 minutes to help the ion pumps pull the vacuum down.
  14. Once the base pressure is in the low 10-7 to mid 10-8 range, the system can be baked out to obtain the best possible base pressure.

 

 

 

660 Scanning Auger Bake-out procedure

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660 Scanning Auger Bake-out procedure.

This procedure is written for the PHI 660 scanning Auger system but also works for the 600 scanning Auger systems as well.

  1. Ion pumps must be on and the system vacuum should be in the mid to low 10-7 range (or better)..
  2. Make sure that the card rack power supply is OFF. Also make sure that these units are OFF:
  • 20-610 High Voltage Supply
  • 20-622 Gun control
  • 11-065 Ion gun supply
  • Balzers Thermo Valve Control  (gas valve also needs to be closed)
  1. The DIGIII ion gauge control and Boostivac ion pump control  should be ON.
  2. Remove all cables that are above the table top. These include the Auger analyzer, SIMS analyzer (if so equipped), 96A V/F preamp, 1182 or 1120 amplifier discriminator, and the 97 SED preamp.   TIP: Make sure that the cables are labeled as you remove them.
  3. When removing the 97 SED preamp be careful not break the feedthrough pins!  Also when you put it back on after the bake-out make sure it is flush with the flange and then use a flat blade screwdriver to tighten the screws – snug plus 1/8 to 1/4 turn.
  4. Remove the filament cap on the top of the analyzer (3 screws at the base, do not unscrew the cable!).
  5. All of the cables above the table top should now be removed.
  6. Remove the wooden tabletops.
  7. Pull up on the table top switches.  Note that in some cases the switches need to be pulled all the way up, but in other cases they may just need to spring up after the table tops are removed.  If the bake-out timer does not start, check the table top switches.
  8. Wipe off any fingerprints from the system with Isopropanol (work it may, shine it must!).
  9. Cover all of the windows with aluminum foil. Also cover the stage micrometers and any exposed feedthroughs. If you are uncertain – cover it just to be safe.
  10. Place the bakeout blanket over the vacuum chamber. These blankets have fiberglass in them so use gloves and avoid exposure as much as possible when handling the blanket.  Also some of the blankets use metal Velcro – be careful or your arms will get cut!!
  11. Secure the blanket as well as you can. IMPORTANT: The V1 gate valve should be outside the blanket. Use aluminum foil to seal any gaps in the blanket. If possible cool the V1 gate valve with a small fan.
  12. Turn off the turbo pump.
  13. Turn off the Auto Valve Control
  14. Set the bakeout timer for 8 to 12 hours (8 hours is usually enough)
  15. Press the bakeout ON button and the ovens should come on. If not, check that the table top switches are not being held down by the blanket.
  16. The DIGIII setpoint 4 controls the ovens. If the pressure in the system goes above set point 4 (usually 2 to 4 X 10-6 Torr) then the ovens will shut off until the vacuum recovers.
  17. Once you verify that the system is baking then it can be left unattended until the bakeout is complete.

 

After the Bake-out.

 

  1. After the bakeout is complete, the first step is to remove the bakeout blanket.   If the system is still very hot, then open the blanket just a little bit and let it cool down for an hour or two until just warm. Then remove the blanket.
  2. Install the table tops.
  3. Turn on the AVC.
  4. Make sure that the card rack power and all units (20-610, 20-622, 11-065 and Thermo Valve) are still OFF.
  5. Re-connect all cables and preamps to the system. Use EXTREME CARE when installing the 97 SED preamp.

Once all of the cables have been connected it is safe to turn on the system normally.

It is recommended that the Lab6 filament and 11-065 ion gun control emission current be turned up very slowly the first time that they are used after bakeout in order to give them time to outgas.