Specific Process Knowledge/Thin film deposition/Furnace LPCVD Nitride

From LabAdviser

A few words about the furnace

B2 Furnace LPCVD Nitride: positioned in cleanroom 2

The furnace is a Tempress horisontal furnace. The process is a batch process meaning you can run a batch of 25 wafers at a time. The deposition takes place at temperatures of 800-835 degrees Celsius. The reactive gases are Ammonia and dichlorsilane. The LPCVD nitride has a good step coverage and the film thickness is very uniform over the wafer. We have two standard LPCVD nitride processes: One for depositing stoichiometric nitride (Si3N4) and one for deposition of low stress nitride (SNR). To get information on how to operate the furnace please read the manual which is uploaded to LabManager.

Process Knowledge

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


A rough overview of the performance of LPCVD Silicon Nitride and some process related parameters

Purpose Deposition of silicon nitride Stoichiometry:
  • Si3N4
  • SRN

SRN: Silicon Rich Nitride

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
  • SiHFailed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle _2} ClFailed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle _2} :10-100 sccm
  • NHFailed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle _3} :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)