Numerically evaluated space-charge effects upon the ionic current which determined oxide growth rates revealed modification factors which could change markedly with the oxide thickness. The electric-field modification factors could typically change the rate of oxidation by an order of magnitude. In addition to affecting the rate, the thickness dependence of the modification factors had a large effect upon the growth law. The results of the numerical calculations were compared with, and were found to be in reasonable agreement with, published analyses of the thin-film and thick-film limits. The voltages across the growing oxide were also evaluated, and were compared with the voltages that had been predicted analytically for these limits.

A.T.Fromhold: Solid State Ionics, 1995, 75, 229-39