- Clean PR off mask (if needed):
- Acetone
- IPA
- DI SRD
- O2 RIE 3min 100 W Technics Etcher
- DI SRD again (so PR doesn’t stick to mask in contact mode)
- Clean and Dehydrate Si Wafer immediately prior to spinning
- O2 plasma 200W
- 2 min
- Technics RIE Etcher
- Spin CEE 100 Spinner
- Use chuck that is slightly smaller than substrate
- Coat inside of spinner bowl with aluminum foil for easy cleanup after spinning
- LOR10B 3000 rpm 45 sec, ramp 2000 rpm/sec
- Hot plate bake wafer 200C 5 min
- Spin CEE 100 Spinner
- Use chuck that is slightly smaller than substrate
- S1813 3000 rpm 45 sec, ramp 2000 rpm/sec
- Hot plate bake wafer 110C 1 min
- Suss Aligner
- Hard N2 contact
- 15 sec expose 7mW/cm^2 (~105 mJ/cm^2)
- Develop 300MIF 30 seconds
- DI rinse 2 min, then place inside spin rinse drier (SRD)
- Microscope inspection and measurements
- Liftoff deposition
- Sputter
- Keep total film thickness less than 1/3 of photoresist height (PR ~2um, so film max ~670nm)
- Denton 80: keep power less than or equal to 50W
- Denton 635: keep power less than or equal to 100 W
- TMV: keep power less than or equal to 100 W
- E-gun: Keep temperature readout below 40C
- Liftoff in Ultrasound
- Fill thin glass beaker with acetone and place inside ultrasonic water bath
- Place wafer inside thin vertical wafer dipper and submerge thin glass beaker that has acetone inside it
- Turn on ultrasonic power for >5 minutes or until films have successfully lifted off
- Dip in IPA (do not allow to dry between steps)
- Rinse in DI water and then place inside SRD
- Remove LOR10B by submerging substrate in AZMIF300 developer for 2 minutes
- DI rinse 2 mine then SRD wafer