Results of LPCVD Nitride Flow Calibrations
mcvittie at stanford.edu
Thu Dec 6 13:51:20 PST 2001
Here are the results of the calibrations done on Monday.
Actual NH3 flow = 0.5+1.04*setting in sccm.
Actual DCS flow = 0.6+0.91*setting in sccm.
Basicly, these results say that the NH3 flow is running 4% above the
setting and the DCS flow is running 9% below the setting. These flow
errors are small than I had expected. They do not explain any of the
problems we have seen with films out of the nitride tube. We are
running more tests looking at wet etch rates and bubble formation. On
the bubble problem, our present thinking is that they may have been
there all along for our low stress films and they got worst when we
upped the DCS/NH3 flow rate a few years back to lower the stress.
More information about the tylannitride