ION-BEAM ANALYSIS OF ULTRATHIN DIELECTRIC FILMS

Nuclear reaction analysis and nuclear resonance profiling methods are currently used to study silicon-based ultrathin (thickness < 10 nm) dielectric films, like silicon oxide, silicon nitride and silicon oxinitrides. The nuclear reactions are used to measure the total amounts of hydrogen, nitrogen and oxygen isotopes that take part in the films, with sensitivities as low as 10(12) atoms cm(-2). Nuclear resonance profiling and also step-by-step chemical etching associated with nuclear reaction analyses are used to measure the concentration versus depth profiles of hydrogen, nitrogen, oxygen and silicon isotopes with depth resolutions of about 1 nm. Furthermore, channeling of alpha-particles combined with detection at very grazing angles is used to measure the average stoichiometry of the ultrathin films.