Specific Process Knowledge/Wafer cleaning/IMEC
| Step | Process | Details | Comments | Comments |
|---|---|---|---|---|
| 4.0 | Pre bonding cleaning of Si wafers with cavities and SOI wafers with nitride | Use wafers with cavitys on and SOI wafers
Takes 1½ hours Orient flat to minimize handling Preferable done just before bonding! |
Get CLEAN box for wafers!!! | |
| 4.1 | Piranha | Mixture: H2SO4:H2O2 (4:1)
Temp: 80 degC Time: 5 min (en gul og en sort prik) |
Clean tank (cleanroom 4) 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!
Put into dedicated wet box for IMEC |
| 4.2 | Rinse | 2 min rinse | Put into dedicated wet box for IMEC | |
| 4.3 | IMEC | DI water:5% HF:isopropanol (100:10:1)
Temp: 25 degC Time: 100 sec (to sorte prikker) |
Clean tank (cleanroom 4) and make your own, it needs 2 bottles
Bottle in service room 2 on the left, pump by Leica microscope in cleanroom 3 |
Bottle for mixing is in service room 2, use bHF pump from RCA fumehood!
Put into dedicated wet box for IMEC |
| 4.4 | Rinse | 2 min rinse | ||
| 4.5 | Piranha | Not nitride wafers!
Mixture: H2SO4:H2O2 (4:1) Temp: 80 degC Time: 20 min |
Reuse previous piranha
Makes wafers hydrofilic |
Put into dedicated wet box for IMEC |
| 4.6 | Rinse & spin dry | 5 min rinse | Put into dedicated wet box for IMEC | |
| 4.7 | Put wafers in new clean carrier box |