A physical model based on the statistics of silicon point defects was described in the preceding companion paper to explain the faster oxidation rates of heavily doped silicon. The mechanism by which dopant levels affect the interface oxidation rate was postulated to be an increase in reaction sites or silicon vacancies caused by the shifting of the Fermi level. The predictions of this model for n + and p+ silicon oxidation kinetics are tested in this paper under a wide variety of oxidation conditions. The physical meaning of the model and its implications for other process phenomena are pursued.

Believing that the silicon in rice hull must exist as organosilicon compounds, the authors have undertaken a series of researches so as to gain an insight into the problem. In this paper, experiments including treatment with hydrofluoric acid, extraction with various solvents, hydrolysis with acid and boiling with alkali are described. Dialysis of the products resulting from these experiments has shown definitely that silicon passed into aqueous solution even with a pH at which silica might precipitate. Since lignin does not contain ash, it is supposed that the silicon in rice hull may be combined with the polysaccharide part.