In many studies of oxidation kinetics, it has been observed that
SiO2
growth in dry oxygen in the thin regime (<500Å) is faster than the classic description of growth in thicker layers by a linear‐parabolic relationship. Growth‐rate enhancement in the thin regime was studied in the 800°–1000°C range under a variety of substrate doping densities and
O2
partial pressures using in situ ellipsometry. The enhancement in oxidation rate is found to decay exponentially with thickness, and its thickness extent is approximately independent of substrate orientation, doping density, and oxygen partial pressure; its oxygen pressure and substrate doping dependence suggest that it is caused by physical mechanisms associated with the substrate. Such mechanisms are discussed in part II of this paper (11).
Based upon the linear‐parabolic growth model of silicon oxidation, accurate kinetic rate constants are determined for (100), (111), and (110) silicon oxidized in dry oxygen in the 800°–1000°C range. The oxide growth was monitored by high temperature automated in situ ellipsometry. It is shown that fitting the maximum number of oxidation data points to a linear‐parabolic relationship yields accurate oxidation rate constants that are unique to the oxidation process as described in the Deal‐Grove model, and not just good empirical fitting parameters. This approach is denoted the “optimum
Xnormali
technique.” Both linear and parabolic rate constants exhibit a break in their activation energies at 950°C. This behavior is discussed and interpreted in terms of the viscoelastic properties of
SiO2
.
In many studies of oxidation kinetics, it has been observed that silicon‐dioxide growth in dry oxygen in the thin film regime (<500Å) is faster than predicted by the linear‐parabolic description of the growth of thicker layers. Oxidation‐rate enhancement in the thin film regime was studied in the 800°–1000°C range for a variety of substrate orientations, doping densities, and oxygen partial pressures using in situ ellipsometry. The results were reported in part I of this paper. In this part, the physical mechanisms previously proposed to explain the rate enhancement are discussed. No single model was found to apply under all experimental conditions. A new understanding of the growth‐rate enhancement in the early stages of silicon oxidation in dry oxygen is introduced.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.