Modulab Evaporator

Safety 

• Wear safety glasses.
• Wear vinyl gloves on top of nitrile gloves to prevent contamination in the PVD. 
• The inside of the tool and the fixtures can get very hot. Use caution. 

Allowed Materials and Processes 

• This tool is only used to deposit aluminum.

Restricted Materials and Processes 

Donot use any other material besides aluminum inside MODULABEvaporationSystem.  

1. Check tool status and configuration  

1. Visit http://www.mmf.montana.edu/equipment-status.html.  
2. Request different targets, shields, or gases as far in advance as possible, preferably at least two weeks, by emailing the lab manager and mmfstaff@montana.edu.  

2. Check tool reservations for conflicts and reserve the tool  

3.Check lab status  

1. Check the house N₂bottle pressure. If it is below 300 PSI, report to staff.  
2. Check process gas bottle pressures (Ar, Ar/O₂,O₂,N₂,etc). If any are below 300 PSI, report the shortage to staff.  
3. Turn on N₂for the lab.  

4. Log into SUMS 

5. Turn on Power Striplocated to the rear of theModulabEvap 

6. Equipment checks  

1. Ensure that Compressor, Valve Control Power and Chamber Pressure switches are ON. 
2. Check that all other switches are off.

7. OpenForelineValve 

1. Upon opening, the TurboForelinePressure gauge should indicate a dropping pressure. 
2. Wait untilpressuregaugereads<50mTorrbefore moving on to the next step. 

8. Start Turbo Pump Control 

1. Press START on the Turbo Pump Control panel. 
2. The Turbo Pump will take several minutes to get up to its operating speed of ~27000 RPM. 
   1. The display will indicate when the Turbo Pump has reached its operating speed. 

9. Prepare evaporation sample 

1. Using a pair of scissors and a ruler, measure and cut the evaporation sampleinto a rectangle ofthe desired size.  
   1. Make sure your size is less than 60cm^2, as the PVD can be overloaded.
2. Fold the evaporation sample into a small enough piece so that it can easily fit into the Filament. 
   1. Make sure the folded sample length does not exceed the Filament length.

10. Open Vent Valve to open Chamber door 

1. An audible hissing sound can be heard as the vacuum isreleased. 
2. It takes a minute or two for the door to open.

11. Unload Chamber 

1. Remove Mirror Assembly 
   1. Mirror Assembly rests at the mouth of the chamber. 
   2. When removed, place Mirror Assembly mirror side down for better stabilization. 
2. Remove Wafer Holder 
   1. When removed,place the support screw of the Wafer Holder into one of the holes in the Mirror Assembly, or place it upside down on top of a tape roll.  
3. Remove Filament Shield 
   1. Filament Shield fits snugglyonto the base and may require two hands to remove. 
4. Remove Filament 
   1. Unscrew each clampcounter-clockwise. 
   2. Careful when handling filament as it will become very brittle after repeated evaporations. 

12. Load Chamber 

1. Place evaporation sample into middle of Filament 
   1. Make sure evaporation sample is secure inside Filament.
2. Place wafers into Wafer Holder 
   1. One to four wafers can be loaded into the Wafer Holder. 
      1. If loading 2 wafers, place them opposite each other to keep things balanced. 
   2. Lock wafers into place by pressing the spring clips and sliding wafer beneath.
3. Replace Filament into Clamps 
   1. Filament should be resting in the ridges of the screw clamps before tightening. 
4. Replace Filament Shield.
5. Replace loaded Wafer Holder.
6. Replace Mirror Assembly.

13. CloseForelineValve 

14. Close Vent Valve 

15. Open Rough Valve while holding chamber door shut 

1. Door should become sealed to vacuum chamber and Chamber Pressure (Pirani)guageshould indicate a dropping chamber pressure. 
2. All other valves should be CLOSED. 

16. Wait for Chamber Pressure (Cold Cathode) to be <= 200mTorr 

17. When Set Point Light comes on, CLOSE Rough Valve 

1. Set Point light is an LED located on the right. 

18. OpenForelineValve 

19. OpenHiVacValve 

20. Wait10minutes  

21. Check that theChamber Pressure (Cold Cathode) has reached ~10^-5mTorr  

22. Ensure that Deposition Power Control (DPC) is set to ZERO 

23. Turn Deposition Enable switch to ON

24. Slowly increase Deposition Power Control (DPC) to +60% 

1. Increase at a rate of 1% per second. 
2. Ensure thatthe Chamber Pressure (cold cathode) does not rise above 10^-4mTorras you increase the DPC. 

25. Hold for 1-2 minutes to completely evaporate the sample 

1. As Filament begins to glow, evaporation sample should melt and wick onto Filament. 
2. Sample is fully evaporated when individual coils on Filament are visible.

26. Slowly turn Deposition Power Control (DPC) to ZERO 

27. Turn Deposition enable switch to OFF 

28. Let PVD cool for five minutes 

29. CloseHiVacValve 

30. Open Vent Valve to Open Chamber Door 

1. It takes a minute or two for the door to open. 
2. Door should not be forced open, only a small force is necessary to open the chamber. 

31. Unload Chamber 

1. Careful whenhandlingobjects inside the Chamber, astheyare still hot.
2. Remove Mirror Assemblyusing hot pad. 
   1. Mirror Assembly rests at the mouth of the chamber. 
   2. When removed, place Mirror Assembly mirror side down for better stabilization. 
3. Remove Wafer Holder. 
   1. When removed, place the support screw of the Wafer Holder into one of the holes in the Mirror Assembly, or place it upside down on top of a tape roll.  
4. Remove Filament Shieldusing hot pad. 
   1. Filament Shield fits snuggly onto the base and may require two hands to remove. 
5. Remove Filament. 
   1. Unscrew each clampcounter-clockwise. 
   2. Careful when handling filament as it will become very brittle after repeated evaporations. 

32. Unload wafers from Wafer Holder  

33. If done with evaporating, continue to step 34. If doing another deposition, go back tostep 12.

34. Putting away the Filament 

1. If Filament is not very brittle and could be used for another deposition, placeit back in the drawer with the other Filaments. 
2. If Filament istoobrittle and cannot be used for another deposition, place it in therecycled metal bin. 

35. Reload Chamber 

1. Replace Filament Shield. 
2. Replace Wafer Holder. 
3. Replace Mirror Assembly.

36. Close Vent Valve 

37. CloseForelineValve 

38. Open Rough Valve while holding chamber door shut

39. Wait for the Chamber Pressure (Pirani) gauge to pump down to <50mTorr 

1. This will take several minutes.

40. Close Rough valve 

41. Ensure that all valves are CLOSED 

42. Stop Turbo Pump Control 

43. Turn off Power Strip