Activation energy of thermally grown silicon dioxide layers on silicon substrates

A detailed numerical consideration is used as basic approach for calculating profiles of activation energy versus oxide thickness for various temperatures between 780 and 930 degrees C. Results presented here are intentionally not based on models of diffusion and reaction kinetics to avoid introducing correction terms due to the expansion of theory still under discussion. The statistical calculation gives the mean activation energy of 2.01 eV with standard deviation of 0.10 eV, very close to the overall activation energy of 2.05 eV [M. A. Rabie, Y. M. Haddara, and J. Carette, J. Appl. Phys. 98, 074904 (2005)]. More instructive features of the thermal oxidation of silicon have been disclosed directly from measurements of oxide thickness with time [M. A. Hopper, R. A. Clarke, and L. Young, J. Electrochem. Soc. 122, 1216 (1975) and J. Blanc, Philos. Mag. B 55, 685 (1987)]. Graphs of the natural logarithm of the growth rate versus oxide thickness, in the range between 2 and 65 nm, show that the oxide thickness influences the activation energy E-A between 1.4 and 2.7 eV. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim