In this work, we make steps towards developing a new wet-oxidation model of silicon based on electron-stimulated dissociation of H2O molecules. The need for a new model arises from the fact that existing physical models are inadequate to describe the thin-oxide regime. Two regimes of silicon oxidation are assumed to exist. The first regime responsible for the growth of up to 2-nm thick oxides including native oxides, considers electron tunneling through the growing oxide. The second regime occurs for thicker oxides and involves conventional diffusion of H2O molecules.