Level 2 Photoresist Removal

Removal of photoresist to prevent contamination of furnaces.

Equipment

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• Solvent waste container
• Microscope

Supplies

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• Acetone
• IPA
• DI water

Operating parameters

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three 15 second acetone rinses

Equipment/controls/tools locations

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Room 50J

• Solvent fume hood
• Microscope

Operating precautions

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Chemical hazard

PR, acetone, and ipa are volatile and flammable. Keep away from flame. Possible biological hazards: only use in a fume hood.

Operating procedure

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1. Initial PR Removal: Hold your wafer level over the waste acetone/IPA container (with the lid off) and squirt acetone on the wafer until it begins to flow off the edges. Let it dissolve the PR for 10-15 seconds before tossing the acetone into the waste container. Repeat until most of the PR is gone (~3 times).
2. Strip off any remaining PR residue by following the standard degreasing procedure (Acetone, IPA, DI, IPA, N2 dry.)
3. Inspect the wafer under a microscope for PR residue. Go back and degrease if necessary. Incomplete photoresist removal is the most common cause of furnace tube contamination. Please inspect wafers thoroughly.
4. Using the LDS 4PP, measure sheet resistance as before. Use the sheet resistance measurement area just opened up for phosphorus predeposition.  Consult Appendix F if necessary.
   
   Boron drive:
   Type ____ R_s1 = ____ Ω/sq.
   
   Enter your R_s value into your logsheet ASAP using the LDS 4PP software.