Quantitative SIMS Depth Distribution of Nitrogen in Nitrided Oxide at the SiO2/Si Interface

Nitridated gate oxides are quite common to be used in VLSI/ULSI MOS devices. Since this material presents several advantages compared with traditional silicon oxide [1, 2], there are strong research efforts both in developing it and in studying its chemical and electrical properties. To estimate the distribution of nitrogen in nitridated oxide, electron spectroscopies (Auger, XPS) have been frequently employed [3]. The limit in their sensitivity is around 1021 atoms/cm3. SIMS studies have been seldom used and normally applied to measure the hydrogen content [4,5,6]. In this paper we present SIMS analytical methodology giving a quantitative nitrogen distribution in systems like SiOxNy/Si by employing of suitable standards. To get a proper quantification at interface region we used as RSFs a linear extrapolation of Si and SiO2 RSFs weighting them by a factor proportional to tht oxigen signal