Specific Process Knowledge/Thin film deposition/Furnace LPCVD TEOS

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LPCVD (Low Pressure Chemical Vapor Deposition) TEOS

B3 Furnace LPCVD TEOS: positioned in cleanroom 2

At the moment there is one furnace for TEOS oxide depositions at Danchip. The furnace is a Tempress horizontal furnace. The process is a batch process meaning you can run a batch of 10 wafers at a time. The deposition takes place at temperatures of 725 degrees Celsius. The reactive gases are dinitrogenoxide and silane. The LPCVD TEOS has a excellent step coverage and extreamly good for trench filling and the film thickness is very uniform over the wafer. We have two standard LPCVD TEOS processes: One that opens slowly for depositing thick layers (>750nm) and one for deposition of thin layers that opens faster. To get information on how to operate the furnace please read the manual which is uploaded to LabManager. Remember to anneal the TEOS oxide to improve the electrical properties as well as chemical resistance.

Process Knowledge

Please take a look at the process side for deposition of TEOS oxide: Deposition of Silicon Nitride using LPCVD

Overview of the performance of LPCVD Silicon Nitride and some process related parameters

Purpose Deposition of TEOS silicon oxide
  • Deposition of silicon oxide on silicon nitride
  • Deposition of silicon oxide on structured surfaces, eg. to cover holes or sealing small cavities.
Performance Film thickness|
  • Si3N4:~50Å - ~3000Å
  • SRN: ~50Å - ~10000Å
Step coverage
  • Good
Film quality
  • Dense film
  • Few defects
Process parameter range Process Temperature
  • 800-835 oC
Process pressure
  • 80-230 mTorr
Gas flows
  • SiHCl:10-100 sccm
  • NH:10-75 sccm
Substrates Batch size
  • 1-25 4" wafer per run
  • Deposition on both sides of the substrate
Substrate material allowed
  • Silicon wafers (new from the box or RCA cleaned)
    • with layers of silicon oxide or silicon (oxy)nitride (RCA cleaned)
  • Quartz wafers (RCA cleaned)