CMP System - Chemical Macanical Polisher System Contact Information:   Faculty Contact:   Aaron Hawkins   Staff Contact:   Don Dawson   Student Contact:   Seungmoo Kim Maintenance Request for CMP System - Chemical Macanical Polisher System

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1. General Description
   
   1. The Chemical Mechanical Polisher (CMP) is used to polish 4" (or 6") wafer by using chemical and mechanical polishing method. It can planarize the wafer which has different material. The following material can be polished by using CMP system:
      1. Silicon Dioxide
      2. Polysilicon
      3. Silicon Nitrite
2. Operating Instructions
   
   1. Turn on the power, log on the software (Username: Seung, Password: Seung)
   2. Setup:
      1. Activate Pad Conditioner in Auto Mode: Select the check box to activate the pad conditioner for use in Auto Mode (This is done after the Pad
      2. Conditional Enabled and Home Pad Condition)
      3. Pad Conditioner Enabled: Select the check box to enable the pad conditioner for general use on the machine. (This box must to be checked to allow the pad conditioner to work)
      4. Home Pad Conditioner: Touch this button to home the pad conditioner when the machine is started.
      5. Chuck Homing Enable: Uncheck (Usually for square wafer)
         1. Chuck Blow Off Set Point (psi): 20; 30 is the max, when long time polishing
      6. Auto Cycle Chuck Blow Off Time: 5; 7-10, when long time polishing
      7. Wait After Wafer Load: 3 sec.
      8. Control by Temperature: Uncheck
      9. Fluch Chuck after polish: Select the check box to flush the wafer carrier after a polish cycle.
         1. Flush with DI Water for (sec): 3-5
         2. Flush with Air for (sec): 7-10
      10. ViPRR Retaining Ring (Bottom part of the wafer carrier):
          1. Total Area: Wafer area
          2. Offset: Wafer carrier weight (if we keep using the same wafer carrier, we don’t need to change this)
          3. Coefficient: Friction coefficient of the retaining ring
          4. If wafer slips off during a polishing process, check the retaining ring (wears).
      11. Wafer Size: 100mm Round
      12. Load station: Hydro Lift
3. Recipe
   
   1. Break in Zone
      1. Conditioning pads.
      2. Done for new pad or for pad not being used for long time.
   2. Polishing
      1. Time (sec.): Polishing time set point (0-500)
      2. Down Force (psi): Polish down force set point (0-10). At less 1 psi higher than back pressure
      3. Table RPM: Table speed set point
      4. Chuck RPM: Chuck (wafer carrier) speed set point
      5. Back Pressure (psi): Wafer backpressure set point. (-14-+10, less than 0 means vacuum) (Help to improve an uniform polish, negative pressure (vacuum) is used usually)
      6. Ring Force (lbs.): Retaining ring (ViPRR) set point. (0-10) Table Temp: We don’t use it
      7. Slurry 1 (ml/mim): Slurry pump 1 flow set point (0-500) (Usually < l00ml/min)
      8. Slurry 2 (ml/mim): Slurry pump 1 flow set point (0-500) (Usually < l00ml/mim)
      9. Rinse (on/off): Turn the DI water rinse on or off during the polish cycle
   3. Condition Zone
      1. In-situ conditioning: for long time polishing (outer: 1, inner: 6 for 1” oscillation of polishing arm)
      2. ex-situ conditioning: for short time polishing. (< few minutes)
   4. Wet idle
      1. To flood DI water for pad and carrier
   5. Auto
      1. Start Polishing: Touch this button to start the currently download process recipe. (Current step is highlight)
         1. Start Conditioning: Touch this button to start the currently download conditioning recipe.
      2. Stop: Touch this button to stop the currently running auto cycle.
      3. Next Step: Touch this button to advance the current polish step.
   6. Calibration:
      1. Down force calibration
         1. Overarm setpoint dead weight: Moving the line of set up value VS actual force either up or down linearly
         2. Overarm setpoint gain: Changing slope of line of set up value VS actual force.
         3. Datasheet for the set up value VS force to get:
      2. Overarm down force display calibration
         1. After the down force calibration, this overarm down force display calibration is done.
         2. To get the same number from the display for the given setting point.
   7. How to use BYU calibrating potable indicator
      1. Zeroing
      2. Press CAL
      3. Adjust span
      4. Put the detector to the weight
      5. Check the weight of weight for the calibration
      6. Set the weight to zero with ZERO set button
      7. Put another metal plate then place plate with the sensor on the top.
      8. Place it on the pad and doing the calibration.
      9. *The sensor and indicator are so sensitive. Please treat with a care.
   8. Slurry calibration
      1. *Purpose: to check the slurry flow rate.
      2. At manual mode: Turn on slurry (make sure your polishing arm is on top of the pad)
      3. Measure amount of slurry actually dispensed and compare with the set up point.
      4. In set up menu: Change calibration factor to increase the actual slurry dispensing amount or decrease it.
      5. For more slurry, decrease the number
      6. For less slurry, increase the number
   9. Wafer carrier cleaning and assembling procedure
      1. Unscrew 8 screws for back plate.
      2. Unscrew 3 lifting posts for mounting ring. (Inspect lifting posts)
      3. Inspect drive post
      4. Unscrew 3 stainless steel screws. (Inspect screws)
      5. Clean all parts.
      6. Check 0-ring for the base plate.
      7. Take the Gimball out with hammer. Inspect. If it is scratched, replace it.
      8. To install new Gimball, use white plastic tool to position the Gimball properly. First put Gimball into the Gimball house. Second place plastic
      9. tool. Third, hammer on it to let Gimball be installed firmly.
      10. Reassemble all parts.
      11. Turn the carrier around
      12. Take out the retaining ring
      13. Take out Bladder (inflatable seal - black rubber)
      14. Clean them
      15. For new insert, take out paper cover to expose glue side and align to the bottom plate with two small holes.
      16. Place the retaining ring
      17. Put wafer
      18. Use height measure (Mitutoyo) to properly adjust the retaining ring position.
          1. Set the height measure read to be 0 at the middle
          2. Move to out side of insert and let the height measure probe is on the retaining ring side.
          3. The number should be around 1/3 of the thickness of wafer.
          4. For higher retaining ring for thicker wafer, use retaining shim under the retaining ring.
      19. Put the inflatable seal with retaining ring. (You need to move around to get right position
      20. It is about done! Put something on the table before you turn the thing over to protect new insert.
      21. Put the wafer carrier in the wafer pickup station
      22. In manual operation, move the arm down to the wafer carrier
      23. In setup operation, Turn off the retaining ring
      24. Move up the arm
      25. Put two more clamps to hold the wafer carrier.
      26. Turn on the retaining ring at setup menu.
4. Manual Operation
   
   1. Manual loading and unloading wafer process
      1. Spindle flush at pad (When you reassembled the wafer carrier)
      2. Blow off at pad
      3. Put sample
      4. Move arm to pick up the sample
      5. Turn on vacuum
      6. Press Rinse/Lift
      7. Move up the overarm
      8. Turn off Rinse/Lift
      9. Move down overarm
      10. Turn off vacuum
      11. Turn on Blow off
      12. Move up overarm
      13. Turn off Blow off
5. Maintenance Tips
   
   1. Keep table and pad wet after use
6. Other Information
   
   1. Compressed air pressure should be >l00psi. For our 4” wafer polishing, our current pressure (80psi) will be fine.
   2. Water pressure from chiller to table should be < l0psi (normally 7-8psi)
   3. For operation with door open, uncable 1,2 and short 3,4.
7. Troubleshooting
   
   1. If there is any question, please email the contact staff above for more information.