Specific Process Knowledge/Wafer cleaning/IMEC
IMEC process for cleaning of wafers before fusion bonding:
Ophav IMEC Spørg Karen om der er lavet modificeringer
| Step | Process | Details | Comments | Comments |
|---|---|---|---|---|
| 1 | Pre-bond cleaning of Si wafers prior to fusion bonding. |
|
Get CLEAN box for wafers!!! | |
| 2 | Piranha | Mixture: H2SO4:H2O2 (4:1)
Temp: 80 oC Time: 5 min (a yellow and a black spot) |
Clean tank (cleanroom 4, 7-up bath for wafers) and make your own or make in dedicated glass.
Pour up H2SO4 first, put wafers in carrier (USE this in steps4.1-4.6), add H2O2, wait 30 sec, dip wafers. |
Maybe clean the tank the day before! |
| 3 | Rinse | 2 min. rinse | Put into dedicated wet box for IMEC | |
| 4 | IMEC | DI water:5% HF:isopropanol (100:10:1)
Temp: 25 oC Time: 100 sec (two black spots) |
Clean tank (cleanroom 4, tank for buffer with wetting solution) and make your own. Mix in dedicated bottle (IMEC) in fume hood and add to tank using BHF pump from RCA fumehood! |
. |
| 5 | Rinse | 2 min. rinse | Put into dedicated wet box for IMEC | . |
| 6 | Piranha | Not nitride wafers!
Mixture: H2SO4:H2O2 (4:1) Temp: 80 oC Time: 20 min |
Re-use previous piranha
Makes wafers hydrophilic |
. |
| 7 | Rinse & spin dry | 5 min rinse | . | . |
| 8 | Put wafers in new clean carrier box | . | . | . |