Oxidation of hydrogenated crystalline silicon as an alternative approach for ultrathin SiO2 growth

Abstract

This article is devoted to the growth of thin thermal SiO2 layers on hydrogenated Si substrates as a possibility to obtain improved properties of oxide-Si structure for contemporary MOS devices. Spectral ellipsometry and atomic force microscopy have been applied for characterization of the SiO2/Si interface and surface morphology. The results show that the oxidation kinetics obeys longer linear time dependence in thin-film regime. The smaller activation energies and higher initial oxide growth rates indicate facilitation of oxide growth in the early oxidation stage. Formation of a reactive less dense Si surface layer is suggested to be responsible for the higher kinetics rates and oxide thicknesses in the very initial stage. © 2005 IOP Publishing Ltd.