MEASUREMENTS OF THE ACCUMULATION OF HYDROGEN AT THE SILICON SILICON-DIOXIDE INTERFACE USING NUCLEAR-REACTION ANALYSIS

First measurements of the accumulation of hydrogen at the SiSiO2 interface using NRA have been performed with the 15N technique. It is found that the measured levels are on the order of 1019-1020 cm-3 or ∼ 1013 cm-2. The spatial distribution is found to extend about 6 nm, with the centroid located about 4 nm from the optically determined interface. The importance of the influence of the surface layer, through the near-resonance cross section, to the investigation of thin, 30-50 nm, films is described. It is shown that the buildup of hydrogen at the Si-SiO2 interface is linearly related to the accumulated dose of the 15N analyzing beam. © 1990.