Difference between revisions of "Wafer scanning process traveler"

From UCSB Nanofab Wiki
Jump to navigation Jump to search
Line 41: Line 41:
  
 
== Plotting data ==
 
== Plotting data ==
 +
Make an excel sheet.
 +
 +
Enter info for Gain4 (particles#1, particles#8, LPD, haze) before and after process calibration.
 +
 +
Enter info for Gain2 (particles#1, particles#8, LPD, haze) before and after process calibration.
 +
 +
For each gain figure out delta ( LPD after- LPD before).
 +
 +
Make a plot  delta vs. time).

Revision as of 15:26, 31 March 2020

The wafers used for process calibration are ordered from SVM. These are 4 inch silicon wafers with low particle count (LPD= light particle detection<100). The box with 25 wafers is stored in the cleanroom and used only for process calibration. Wafers are handled very carefully, because with every loading and unloading some particles will be added.

Scanning procedure

before process calibration

  1. Log in (access code is boss)
  2. Load desired number of Si wafers to the carrier that says " SURFSCAN" .
  3. Place the carrier with wafers to the right indexer.
  4. Select in the menu option "CAS" (this will read all wafers that are in the carrier)
  5. Load one of standard recipes
  6. Select one of the recipes:
    • UCSB Gain4 ( measuring small particles 0.16-2.8um)
    • UCSB Gain2 ( measuring larger particles 2.8-28um)
  7. Select one of the recipe, modify it if needed, default the bin
  8. Select the wafer you want to scan
  9. Press SCAN
  10. Wait until scan is finished
  11. Record: LPD, particles #1, particles #8, haze
  12. Take a picture of the scan (by phone)
  13. Select "Home" so indexer moves up to loading/unloading positon
  14. Wafers are ready for process calibration

after process calibration

  1. Log in (access code is boss)
  2. Load treated Si wafers to the carrier that says " SURFSCAN" .
  3. Place the carrier with wafers to the right indexer.
  4. Select in the menu option "CAS" (this will read all wafers that are in the carrier)
  5. Load one of standard recipes
  6. Select one of the recipes :
    • UCSB Gain4 ( measuring small particles 0.16-2.8um)
    • UCSB Gain2 ( measuring larger particles 2.8-28um)
  7. Select one of the recipe, modify it if needed, default the bin
  8. Select the wafer you want to scan
  9. Press SCAN
  10. Wait until scan is finished
  11. Record: LPD, particles #1, particles #8, haze
  12. Take a picture of the scan (by phone)
  13. Select "Home" so indexer moves up to loading/unloading positon
  14. Unload the wafers

Plotting data

Make an excel sheet.

Enter info for Gain4 (particles#1, particles#8, LPD, haze) before and after process calibration.

Enter info for Gain2 (particles#1, particles#8, LPD, haze) before and after process calibration.

For each gain figure out delta ( LPD after- LPD before).

Make a plot delta vs. time).