Standard Operation Procedure for Furnace Process
Purpose: to anneal or to deposit a layer of polysilicon, doped silicon, wet oxide, dry oxide, nitride, n-type and p-type doping, HTO
Location: Pettit and Marcus Inorganic Cleanrooms
Tools: Tystar Nitride Furnace Tubes 1-4 (Pettit), Tystar Poly Tubes 1-4 (Pettit), Lindberg Furnace Tubes 1-4 (Pettit), Tystar Mini Tubes 1-3 (Marcus)
Supplies Needed: appropriate size boat for sample, all supplies necessary for piranha clean, test wafer/wafer pieces, witness wafer/wafer piece (if necessary)
Setup Procedures:
1. Schedule enough time for the tool, well in advance of the process.
2. Run a test run to check the deposition rate.
a. For a test run, use a similar amount of wafers for a more accurate deposition rate.
3. Wafers must be piranha-cleaned immediately before they are put into the furnace (please see the cleaning section for more information).
4. Check the furnace tube and make sure it is not flaking.
5. Check to make sure the boat necessary for the size wafers you are processing is in the tube.
a. If you cannot find the boat you need, check the dry boxes across from the furnaces.
Number of substrates: pieces to 6” wafers, up to a full cassette of 4” wafers
Process Parameters:
1. Use the vacuum wand on the furnace to load your wafers onto the furnace boat.
a. If necessary, also load witness wafers.
2. Load the furnace boat onto the tube shelf.
3. Check the furnace periodically while the process is running.
a. Make sure the furnace does not go into a special hold (SHLD) step.
b. Check and note the parameters to make sure everything stays near the set point.
4. Allow the wafers to cool while the boat is out. (5 min)
a. If wafers cool too fast, they could shatter.
5. Remove the samples from the boat.
6. Measure the samples or witness wafers to check the deposition thickness.
7. Rerun the samples with the new deposition thickness, if necessary. If the deposition is complete, log off the tool and cancel any unused time that was scheduled.