Operating instruction for Metal Evaporator (AUTO 306)

Note: words with capital letters are messages on the display. Words in italics are buttons for operations. If a button has red light that means, that it can be pressed.

Power on

  1. Rotate the black power knob from “0” to “1” and look at the display.
  2. If it says “POWER FAIL” then press RESET and then START button.
  3. If still you see “POWER FAIL” message, turn off the power by rotating the black knob from position “1” to “0”. This equipment needs to be fixed, notify Shailesh.
  4. If display shows “PUMP WARM UP” then machine is warming normally.
  5. When “PUMP WARM UP” message is shown that means the system is warming up, usually it takes 45 minutes to warm up.

Loading the sample and Aluminum metal

  1. While “PUMP WARM UP” appears on the display prepare to load the sample and Al wire. To do this press VENT. Wait for 5 minutes so that the chamber reaches atmospheric pressure (7.6*10² Torr)
  2. Remove top steel plate and then the outer cover (glass jar) be careful about lifting the glass jar because it is very heavy. Gently put it on the bench.
  3. Load a new tungsten boat. To do this first unscrew and remove the old tungsten boat. Screw tight the new boat and put small amount of Al (after making it like a bundle) in the boat.
  4. Close shutter above the boat so that Al does not evaporate and released automatically when the boat is heated.
  5. Using adhesive tape place your samples on the top of the cap. Make sure they stick together.
  6. Place a new glass plate on the window of the glass jar. This transparent plate allows you to see the boat and aluminum when they are red hot.
  7. Make sure that there is no dust on the base of the evaporator and at the bottom of the glass jar. Then slowly put down the glass jar on the base after making sure that the glass plate which you attached in step 11 is not knocked off.

Creating vacuum in the chamber

  1. Put the steel plate on the top and press CYCLE to initiate the normal process for metallization.
  2. Now the display would say “ROUGHING”. The chamber pressure, shown at the bottom of the display would be decreased. For example, “CHAMB=1.4 -1 Tr” means that the chamber pressure is 1.4*10 Torr. In comparison the atmospheric pressure is 760 Torr.
  3. Next message will be “PUMP DOWN”, you will see that pressure is going down.
  4. If everything is working fine then the display panel will changed to “FINE PUMPING” message. This happens when the diffusion pump turns on. It starts to bring down the pressure and increase the vacuum. When message window shows “4 -5” (4*10 Torr) then the system is ready for Al evaporation.
  5. Sometimes when the chamber pressure is about 5*10 Torr, the display panel shows message “HIGH VACUUM FAIL”. That means the diffusion pump failed to work. At this point you should press RESET and then CYCLE. It is likely that now you will see the message “FINE PUMPING”. If you again see the message “HIGH VACUUM FAIL” then it is possible that there is a leak between the glass jar and base. Press VENT and after wait 5 minutes, remove glass jar and wipe off the base and the rubber ring.Reassemble the chamber and press CYCLE and go to step 15.

Aluminum evaporation

  1. Turn the heating knob to “LT”.
  2. Slowly increase the current and look to the tungsten boat for a sign of redness through the glass window.
  3. Keep increasing the current slowly until it reaches 2 A. You should see a red hot tungsten boat with meting Al in it.
  4. When you see that Al is melted remove the shutter from the top of tungsten boat. Al will be evaporated and deposited on the samples.
  5. After 1 min. close the shutter and reduce the current to zero.
  6. Turn off the current by rotation heating knob to initial position.

Sample removal and shut down

  1. After Al is evaporated, wait for 5 min. for the system to cool down. Then press VENT. Diffusion pump will turn off. Air will enter the chamber and you will hear the sound of air entering. Display will show “CHAMBER VENT”.
  2. Wait for 5 min. so that the chamber is at the atmospheric pressure. Then remove the steel plate from the top and remove the cap with the sample.
  3. Remove the sample and put back the cap. Also place the steel plate on the top.
  4. Now you need to produce some vacuum before turning off the machine. Press CYCLE again to start the process of vacuum production. Now display will show “ROUGHING”. That means pressure is going down.
  5. When vacuum reaches 10 Torr, press SEAL.
  6. Press STOP. The display will show the message “DIFFUSION PUMP OFF”.
  7. Turn off the black power knob from position “1” to “0”. Note that before to turn power knob to position “0” you must press STOP.