Specific Process Knowledge/Thermal Process/Annealing
Annealing
At Danchip we have seven furnaces and an RTP for annealing: A1,A3,C1,C2,C3,C4, noble furnace and RTP. Annealing normally takes place in an N atmosphere. PECVD PBSG is annealed in an wet atmosphere which will also oxidize the silicon substrate.
- Anneal with N can be done in furnaces:A1,A3,C1,C2,C3,C4, noble furnace and RTP
- Wet anneal with HO in a bubbler can be done in furnaces:C2 and C3.
Comparing the seven annealing equipments
| ' | A1 Boron drive-in | A3 Phosphorous drive-in | C1 Gate oxide | C2 Anneal oxide | C3 Anneal bond | C4 Anneal aluminium | Nobel furnace | RTP |
| General description | Drive-in of boron deposited in the boron pre-dep furnace(A2) or drive-in of ion implanted boron. Can also be used for dry and wet oxidation. | Drive-in of phosphorous deposited in the phosphorous pre-dep furnace(A2) or drive-in of ion implanted phosphorous. Can also be used for dry and wet oxidation. | Oxidation of gate-oxide and other especially clean oxides. At the moment also used for general oxidation of 6" wafers. | Annealing and oxidation of wafers from the B-stack and PECVD1. | Annealing and oxidation of wafers from NIL. | Annealing of wafers with aluminium on. | ||
|---|---|---|---|---|---|---|---|---|
| Dry annealing | x | x | x (with special permission) | x | x | x | x | x |
| Wet annealing with bubler (water steam + N2) | x (with special permission) | x | x | |||||
| Process temperature | 800-1150 oC | 800-1150 oC | 800-1150 oC | 800-1150 oC | 800-1150 oC | 800-1150 oC | 800-1150oC | ? |
| Batch size | max. 30 wafers of 4" or 2" | max. 30 4" wafers or 2" wafers | max. 30 wafers of 6",4" or 2" | max. 30 4" wafers or 2" wafers | max. 30 4" wafers or 2" wafers | max. 30 4" wafers or 2" wafers | ? | ? |
| Which wafers are allowed to enter the furnace: | A1 Boron drive-in | A3 Phosphorous drive-in | C1 Gate oxide | C2 Anneal oxide | C3 Anneal bond | C4 Anneal aluminium | Nobel furnace | RTP |
| New clean* Si wafers 4" (6" in C1) | x | x | x (with special permission) | x | x | x | x | x |
| RCA clean** Si wafers with no history of Metals on | x | x | x (with special permission) | x | x | x | x | x |
| From Predep furnace directly (e.g. incl. Predep HF**) | From A2 | From A4 | ||||||
| Wafers directly from PECVD1 | x | x | x | x | x | |||
| Wafers directly from NIL bonding | x | x | x | x | ||||
| Wafers with aluminium on | x | x | x | |||||
| wafers with other metals | x | x | ||||||
| wafers with III-V materials | x |
*New clean: only right from the new clean box. It is not allowed to put them in another box first.
**These wafers must be placed in a "transport box from RCA to furnace" using the RCA carrier when doing RCA or the pre-dep carrier after pre-dep.