Defect microchemistry at the SiO2/Si interface

The intrinsic oxide decomposition reaction Si+SiO2 yields 2SiO gas at the SiO2/Si interface is shown to be nucleated at existing defect sites prior to the growth of physical oxide voids. At lower temperatures than needed for void formation, these defects become electrically active, leading to low-field dielectric breakdown unless sufficient O2 is available (low concentrations). The systematics of the required O2 suggests strongly that it reverses the initial decomposition by reoxidizing the SiO product at the interface. (Author)