Formation of modified Si/SiO2 interfaces with intrinsic low defect concentrations

The modification by postoxidation NO treatments of the Si/SiO2 interface in thermally grown Si(100)/SiO2 layers has been studied by nuclear reaction analysis and electron paramagnetic resonance spectroscopy. Our results demonstrate a selective incorporation of NO molecules at the Si/SiO2 interface and a drastic reduction in the interface defect density. In this new configuration, the Pb center density, which is typically 2x10(12) cm(-2) in the as oxidized samples, is reduced to below 10(11) cm(-2) without any hydrogen passivation. The thermal treatment in NO atmospheres opens the perspective for the formation of hydrogen free low defect Si(100)/SiOxNy interfaces conserving the qualities of the SiO2 dielectric. (C) 1999 American Institute of Physics. [S0021-8979(99)05906-X].