Thermco1:
As of 8/1/23, Thermco1 is shut down and will be permanently removed from the cleanroom. It will be replaced by a new Tystar furnace in March 2024. Find the current project schedule and more information here
Thermco 3, and 4 furnaces are used for wet and dry oxidation processing and N2 annealing.
Thermco Oxidation and Annealing Furnaces, Thermco, 3, and 4
Training To Become a Tool User
Process Monitoring and Machine Qualification
Post-Process Measurements & Reported Data
Thermco1 and 3 are for clean work only. The wafers processed in those furnaces are MOS clean, meaning that they have never had metal deposited on them, have been through a full KOH decontamination procedure and have not been processed in any equipment which is considered contaminated (sometimes referred to as ‘gold contaminated’).
Wafer must have undergone a full Pre-Diffusion Clean or Pre-LPCVD Clean done at wbclean1-2 within 60 mins of loading into Thermco1-3.
Thermco4 is in the flexible cleanliness group.
Check Tube Status
Thermco will now alternate between the Gas System screen and the Main Furnace screen.
Load Recipe
Thermco will flash orange Recipe Compile Succeeded once recipe is loaded.
Run Program
Users may perform the specified qual process before tool use if more recent qual data is desired for reference.
The tool will be reserved for 3 hours on Badger, as the run normally takes over two hours. Three freshly RCA cleaned 4" L test 100 Si wafers will be run in the WETOX recipe with a 39-minute oxidation time at 900 Celsius.
All Thermcos undergo the same WETOX process for quals. WETXOX and DRYOX processes produce comparable results, however a WETOX process is generally less time-consuming than a dry process. If off-nominal results are produced from the WETOX qual, a DRYOX process may be run to determine the source of the anomaly.
Instructions are listed on the tool binder located in the vicinity of each corresponding tool. Once your wafers have boated in and the process starts, the remaining process run time can be monitored via the green timer numbers on the corresponding Thermco's control panel (where the Start and Stop button are located). Once the timer reaches 0 minutes remaining, the furnace must cool to 800C at all three set points before you can boat out your wafers. You can check the furnace temperature via the Tube Status screen.
Some important notes to remember are:
Wafers are to be placed in a 50-wafer spread (as shown in Figure 1 below):
Figure 1: Wafers should be loaded with flats up and shiny side towards the door (away from the furnace) when the boat is out.
A 9-point spectroscopic ellipsometry measurement will be made on the Woollam for each wafer.
Qual data may be found on the Lab Management System (LMS) comment log. Standard data findings are listed in parenthesis.