Effect of incorporated nitrogen on the kinetics of thin rapid thermal N2O oxides

Abstract

We have grown ∼10 nm O2 and N2O-oxides on Si(100) by RTO (rapid thermal oxidation) over the temperature range 800–1200 °C. Although the growth rates of both oxides exhibit Arrhenius behavior over the entire temperature range, the N2O-oxides exhibit a large change in the Arrhenius preexponential factor for oxidation temperatures greater than 1000 °C. Above this temperature, N2O-oxides grow a factor of 5 slower than O2 oxides. Below this temperature, N2O-oxide growth rates approach those of O2-oxides. This growth rate inflection can be explained in terms of N incorporation, which increases with increasing oxidation temperature. The equivalent of one monolayer of N coverage is achieved at about 1000 °C, coincident with the inflection. The incorporated N retards the linear growth of the thin N2O-oxides either by occupying oxidation reaction sites or inhibiting transport of oxidant species to the vicinity of the interface.