Ion beam analysis (IBA) on the nanometer scale using the time‐of‐flight heavy‐ion elastic recoil detection analysis technique reveals changes in the elemental composition (depth profiling) of high‐temperature nitrided thin silicon oxide (SiO2) layers formed on wafer silicon. An increased uptake of nitrogen with both increased temperature and surprisingly increased thickness of the thin SiO2 layers has been measured. The initial stage of nitridation could be illuminated, indicating the formation of silicon oxynitride subject to nitridation parameters. Previous surface topology investigations with scanning electron microscopy (SEM) revealed concentric annular artificial patterns at the surfaces of specially prepared specimens.

Particle induced γ-ray emission (PIGE) using the 19 F ( p , α γ)16 O reaction and deuterium induced nuclear reaction analysis (NRA) were used to measure the uptake of fluorine in thin silicon oxide films which varied in thickness and had been nitrided under various conditions and annealing treatments. PIGE results show that 66 – 80 ppm of F was found in samples nitrided with F (as approximately 1% SiF 4) in flowing nitrogen and heated at 1300°C for 1 hour. With NRA, it was not possible to measure these low concentrations because the background signal from silicon overlaps with the F signal. The increase of F in the nitrided specimens from 66 to 80 ppm follows an increase in film thickness from 3 to 53 nm indicating that F is incorporated in the film rather than being located at the surface of the specimen.

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