Tube Furnace (Tystar 8300)
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About
The three stack Tystar 8” furnace is used primarily for 3 processes. The processes are dedicated for specific tubes as follows:
- Tube #1: SOG curing & low-temp oxidation
- Tubes #2 and #3: Dry or wet oxidation of silicon (unprocessed, clean)
- Tube #3: General furnace annealing & oxidation, including processed material
Each process tube can accomodate up to one hundred 8” wafers per cycle. We have boats for 2", 3", 4", 6", 8" and irregular shaped pieces. The maximum temperature is 1100°C for the system. Gases used are O2, Steam from DI-H2O, N2.
Process Information
Recipe Characterization Data, such as thermal oxidation times, can be found on the recipe page:
Use the BYU or Stanford Leland Jr. Thermal Oxidation Calculators to determine the time and temperature that will be necessary for your process needs. You can "calibrate" your oxidations to the Stanford calculator by adjusting the Partial Pressure on the calculator to match your experimental data.
Keep in mind that all process must be 30 minutes in length at a minimum. Processes less than 30 minutes will suffer from poor uniformity because the process tube will not have sufficient time to saturate with O2 or DI-H2O.
Gases Available
- N2 (15/5 slpm)
- O2 High-range "O2HI" - 15 slpm
- O2 Low-range "O2LO" - 1 slpm
- All gasses flow through the H2O bubbler, which can optionally be filled with heated water to flow steam, or evacuated (no steam, gas only).
Recipes
The following are the available recipes on each furnace tube:
Tube 1:
- SOG425.001 - Spin-On Glass Cure
- ALGAAS.001 - Oxidation of AlGaAs
- ANNEAL.001 - Anneal with variable time and temp.
Tube 2:
- WET1050.002 - WetOx at 1050°C
- DRY1050.002 - DryOx at 1050°C
- WETVAR.002 - WetOx, variable temp.
- DRYVAR.002 - DryOx, variable temp.
Tube 3:
- WET1050.003 - WetOx at 1050°C
- DRY1050.003 - DryOx at 1050°C
- WETVAR.003 - WetOx, variable temp.
- DRYVAR.003 - DryOx, variable temp.
- ANNEAL.003 - Anneal with variable time and temperature
Process Limits
- Max temperatures:
- Tube 1: TBD, something like 950°C max.
- Tube 2: 1050°C for <<24hr; 1100°C for max. 3hr.
- Tube 2: 1050°C for <<24hr; 1100°C max. 3hr.
- DRY1050 may not be run for more than 3hrs. O2 flow is 3SLPM, which is too high to run for more than 3hr.
- Contact supervisor for other options, such as DRYVAR @ 1100°C, or with lower O2 flow.
- WET1050 may not be run for more than 24hrs without authorization. Contact supervisor if need to run longer.
- No recipe should be run with >1slpm gas flow without discussing with supervisor first, or gas bottles will be depleted very fast and likely run out during your process.
Oxidation Rates & Data
See the above recipes page for data on oxidation rates for standard oxidation recipes.
Useful Information
Tystar Wafer Boat Drawing - 4" Wafer with 0.5mm Slots
See Also
- Tystar - Manufacturer of the tool
- Silicon Thermal Oxide Thickness Calculator (BYU) - Use this on-line calculator to calculate times for silicon oxidation.
- Advanced Silicon Thermal Oxide Thickness Calculator (Stanford Leland Jr.) - Another thermal oxide calculator, with flexibility to vary partial pressure parameter to calibrate to your own process.