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. © 1985, The Electrochemical Society, Inc. All rights reserved.