The gas-phase chemistry of silicon oxynitridation in N2O has been investiga
ted. From an evaluation of available kinetic data, we have developed a mode
l for the thermal decomposition of gaseous N2O. To quantify heat transfer b
etween the N2O gas and the wall of the furnace, we introduce the concept of
referencing to an N-2 gas-temperature profile, measured in an oxidation fu
rnace. Using this model, we can account for the increase with flow rate and
temperature of the NO concentration in the N2O decomposition product, and
the self-heating during decomposition, for furnace processing. This change
in gaseous NO concentration translates to a higher nitrogen content and low
er growth rate for the silicon oxynitride. For rapid thermal and other shor
t-gas-residence-time systems, we show that atomic oxygen is present at the
Si wafer, and that this removes previously incorporated nitrogen.