Specific Process Knowledge/Thermal Process/A3 Phosphor Drive-in furnace

A3 Furnace Phosphorus drive-in

A3 phosphorus drive-in furnace: positioned in cleanroom 2

The A3 Furnace Phosphor drive-in is a Tempress horizontal furnace for oxidation of silicon wafers, annealing of the grown oxide and drive-in of phosphorus after a pre-deposition. Phosphorus pre-deposition takes place in the A4 Furnace Phosphor pre-dep. The A3 furnace can also be used for drive-in of phosphorus which has been ion implanted.

A3 is the third furnace tube in the A-stack positioned in cleanroom 2. The A-stack together with the C2 Furnace Gate oxide are the cleanest of all furnaces in the cleanroom. Please be aware of which substrates are allowed to enter this furnace. Check the cross contamination chart.

The user manual, quality control procedure and results, technical information and contact information can be found in LabManager:

Furnace A3: Phosphor Drive-in

Process knowledge

• Phosphorus drive-in: look at the Dope with Phosphorus page
• Oxidation: look at the Oxidation page
• Annealing: look at the Annealing page

Overview of the performance of the phosphorus drive-in furnace and some process related parameters

Purpose	Drive-in of phosphor, oxidation of silicon and annealing of the oxide.	Oxidation: Dry Wet: with torch (H2+O2)
Performance	Film thickness	Dry SiO2: 50 Å to ~2000 Å (takes too long to make it thicker) Wet SiO2: 50 Å to ~3 µm (takes too long to make it thicker)
Process parameter range	Process Temperature	800-1150 oC
	Process pressure	1 atm
	Gasses on the system	O2, N2 and H2
Substrates	Batch size	1-30 4" wafer (or 2" wafers) per run
	Substrate material allowed	Silicon wafers (new from the box or RCA cleaned) From A4 furnace directly (e.g. incl. Predep HF) In doubt: look at the cross contamination chart or please send a mail to furnace@danchip.dtu.dk.