Descriptionicp

The ATV is a tube furnace that can be used for oxidation, doping and anneals. Process in-liners are used for sensitive processes to prevent cross contamination. Currently the system can support wet/dry oxidation and annealing of 4" wafers and pieces.

Low pressure processing is supported as well.

Available gases are Nitrogen and Oxygen.

Processes

Thermal Oxidation

 

Operating Manual

*Note that the instructions below may not contain the most recent updates. Please refer to the manuals printed and posted at the equipment.

Safety 

  • The furnace gets extremely hot and remains hot to the touch hours after it has been turned off. Use extreme caution and wear necessary heat protection. 
  • Do not place hands or other body parts inside furnace. 

Allowed Materials and Processes 

The Oxidation Furnace (Wet) can be used to create a layer of Oxide on your substrate.  

You can use silicon or glass wafers. 

Restricted Materials and Processes 

Do not place sources from other furnaces in the Oxidation Furnace.  

Important Equipment Notes  

  • Be extremely careful when handling quartz source tray and quartz rod 
  • Wafers may be loaded and unloaded at higher temperature (greater than 400 C) but must be done slowly to not thermal shock the wafers or the sources. 
  • Once unloaded, the wafers should be placed on one of the metal tables to completely cool (usually around a minute) before stored in the plastic case. 
    • Clean a spot on one of the metal tables with a clean wipe and isopropyl alcohol before cooling wafers on it.  
  • Oxygen may also be used during some diffusion runs. If oxygen is needed, turn on the oxygen tank in the back of the clean room and turn on the oxygen valve connect on the right of the furnace. The oxygen gas flow should be set to 9 and left on for the desired time and temperature during the specific diffusion.  

 1. Check reservations and make one 

2. Check tool status and configuration  

  1. Visit: http://www.mmf.montana.edu/equipment-status.html. 

3. Check lab status  

  1. Check that the N2 bottle pressure is above 400 PSI.  
  2. Check that N2 is on for lab.  
  3. If your process needs oxygen or argon, check the O2 orArbottle pressures as well.  

4. Log into SUMS  

5. Equipment checks 

6. Plug in furnace and turn on 

  1. To turn on the furnace, hold the circular power button while switching the main power switch to the on position. 
  2. Continue holding the reset button until the temperature readings appear on the display. 

7. Record experiment parameters in the logbook located in the bin on the wall next to the furnaces

8. Remove beaker from hot plate located at theright-hand side of the oxidation furnace and pull out the black stop 

  1. Be extremely careful when removing beaker from hot plate as there are fragile tubes/quartz pieces surrounding the beaker.  

9. Fill beaker with de-ionized water 

  1. Fill to halfway through the white oval on the beaker for a90-minuteoxidation. 
  2. Fill to slightly over the white oval on the beaker for a longer oxidation.  

10. Replace the beaker on the hot plate, ensuring that the black stop is firmly secured and that the feeder tube is placed in the fitting connected to the oxidation furnace

  1. The feeder tube fitting will be loose, but make sure that the tube is inside of the socket. 

11. Turn on the hot plate and set the temperature knob to 60

12. Once the water is boiling, decrease the temperature on the hot plate to 50

13. Clean quartz rod and metal tray with isopropyl alcohol and clean wipe  

  1. Use the rod and metal tray that are marked with the blue tape.

14. Unload quartz source tray from furnace

  1. Place metal tray at the entrance of the furnace, making sure the furnace tube and the metal tray arelined up and flat. 
  2. Slowly push quartz rod into furnace, making sure to keep the end of the rod as low as possible. 
  3. Hook the end of the rod through the loop on the quartz source tray. 
  4. Slowly pull rod and quartz source tray towards entrance of furnace. 
  5. When you reach the end of the furnace tube and the start of the metal tray, slightly lift the metal tray on the side closest to you.  
  6. Continue to pull the quartz source tray until most of the quartz source tray is on the metal tray.  
  7. Lower the metal tray back down to its original resting position. 
  8. Pull the quartz source tray all the way out of the furnace tube and fully onto the metal tray. 

15. Load desired number of wafers into quartz tray between the two extra wafers 

  1. In other words, make sure that one spare is always in the front of the wafer tray and the second spare is directly behind the last user after loaded in tray. 

16. Reload quartz source tray into the middle of the furnace 

  1. Place loaded quartz source tray on metal tray.  
  2. Hook the end of quartz rod into loop of quartz source tray. 
  3. Gently push metal tray into the middle of the furnace. 
    1. You can check if the metal tray is in the middle of the furnace by marking the spot on the quartz rod that is at the entrance of the furnace. Remove the rod from the furnace and line up the marked spot with the entrance of the furnace on the outside. Where the end of the rod is located is where the start of the quartz source tray is. 

17. Set desired temperature on the master control (center panel) 

  1. The other two zones will be automatically set by the master control.

18. When the temperature of the furnace exceeds 400C, turn on the nitrogen gas and set the flow to 7 

  1. This valve is located at the right-hand side of the furnace. 

19. When the temperature of all three zones reaches the desired temperature, turn off the nitrogen and turn on the oxygen and set the flow of the oxygen to 9

  1. This valve is located at the right-hand side of the furnace next to the nitrogen valve. 

20. Run the oxidation for the desired amount of time 

21. When the desired time has passed, turn off the oxygen and turn the nitrogen back on at a flow of 7

22. Setthe temperature onthe master controlof the furnace to 0 C 

23. Turn off hot plate 

24. Allow the temperature of the furnace to decrease below 400 C 

25. Turn off the Nitrogen gas flow valve 

26. Clean the metal tray and quartz rod with isopropyl alcohol

  1. Use the rod and metal tray that areNOT marked with tape.

27. Unload quartz source tray from the furnace 

  1. Place metal tray at the entrance of the furnace, making sure the furnace tube and the metal tray arelined up and flat. 
  2. Slowly push quartz rod into furnace, making sure to keep the end of the rod as low as possible. 
  3. Hook the end of the rod through the loop on the quartz source tray. 
  4. Slowly pull rod and quartz source tray towards entrance of furnace. 
  5. When you reach the end of the furnace tube and the start of the metal tray, slightly lift the metal tray on the side closest to you.  
  6. Continue to pull the quartz source tray until most of the quartz source tray is on the metal tray.  
  7. Lower the metal tray back down to its original resting position. 
  8. Pull the quartz source tray all the way out of the furnace tube and fully onto the metal tray. 

28. Remove wafers from quartz source tray. 

29. Reload source tray into the furnace once wafers are removed.  

30. Turn off furnace. 

31. If no one else is in the lab, turn off house nitrogen. 

Troubleshooting 

  • Furnace is plugged in but will not turn on.  
    • Check that someone is logged into SUMS 
    • If no one is logged into SUMS contact MMF Staff 
  • Door will not close 
    • Reseat door gasket and try again