Preliminary and fundamental remarks:
- TO OPERATE ON CMi WETBENCHES, PLEASE READ THE MANUEL Wet Benches Safety.
- Any intervention in the wet bench is done only by CMI staff
- This tool is a MICRO-ELECTRONIC compatible tool :
- No organic layers (Photoresist, Kapton, polyimide etc …)
- No gold and copper.
- Metallic layers are not reclaimed in this equipment.
RESERVATIONS RULES AND BILLING POLICY :
- Booking : No restriction
- Reservtion names must be correspond to operators
- Billing : Processing time
- No penalty fees in case of user’s no show
III. Modus operandi
The Plade Reclaim wet bench is dedicated to the reclaim/strip of silicon oxide (SiO2), silicon nitride (Si3N4), polysilicon or amorphous silicon (Si) layers. The bench is equipped with 3 reclaim baths and 2 rinsing baths.
The baths are compatible with 4 or 6 inches wafers. The default configuration is 4 inches, for 6 inches wafers, please contact CMi staff to change the carrier of the dryer. The handling is done with 4 or 6 inches baskets. The baskets are in teflon and labelled “Reclaim” or “POCL”.
The demonimations, the compositions and indicative removal rates of the 3 reclaim baths are summarized in the table below :
Deglaze / POCL3
HF : H2O
1 : 3
HF : H2O
1 : 1
HNO3 : HF : H2O
200 : 12 : 80
Phosphorous contaminated SiO2
SiO2 : 15000 A/min
Si3N4 : 120 A/min
SixNy : 40 A/min
Deglaze / POCL3 bath is dedicated to the removal of the highly doped silicon oxide (SiO2) grown during the POCL3 doping process. The bath is highly contaminated by phosphrous atoms.
HF 49% bath is dedicated to the removal of oxides (Thermal, TEOS, LTO or PVD oxide) and nitrides (stoechiometric or low stress).
Polyetch batch is dedicated to the removal of silicon based layers (amorphous silicon, semi-cristallin silicon and polycrystalline silicon or polysilicon).
- Login on the Plade Reclaim using zone 3 computer.
- Load the wafers in one of the dedicated Teflon carrier and put the handle on.
- Full protection is now required (apron, face shield, chemical gloves) before going further.
- Open the lid of the bath and gently plunge the carrier into it.
- Rinse the gloves and gently clean the bath’s surroundings with a moist paper (several cleanings/rinsings are necessary).
- Wait the end of the etching. Remove the individual protective equipment if the waiting time is long (more than 5 min).
- Open the FFR lid and gently transfer the Teflon carrier from the etching bath to FFR.
- Activate the FFR button.
- During FFR, rinse the gloves and gently clean the etching bath’s surroundings with a moist paper (several cleanings/rinsings are necessary).
- When FFR is finished, switch the Teflon carrier to the Trickle Tank TT.
- Once resistivity is reached (~12 Mohm.cm), put the carrier in the spin rinser and dryer SRD (the carrier’s handle must be removed).
- A recipe is already selected. Just press STOP and START.
- When the SRD is finished, get the wafers back and put the carrier where it belongs.
- Carefully check the cleanliness of the wetbench before taking off the chemical protection (apron, face shield, chemical gloves)
- Perform wetbench logout on zone 3 computer.
Any droplets of any kind MUST be removed from the wetbench before leaving it. Suspicious droplets must be cleared using a moist paper (2 to 3 cleanings/rinsings are necessary) and remaining water droplets must be removed with absorbent paper.