BACKSCATTERING ANALYSIS OF THIN SIO2-FILMS ON SI USING O-16(ALPHA,ALPHA)O-16 3.045 MEV RESONANCE

Very thin SiO2 (less than 200 Angstrom) formed on Si have been investi gated using O-16(alpha,alpha)O-16 3.045 MeV resonant backscattering sp ectrometry. SiO2 films were on Si substrates by usual thermal oxidatio n of dry oxygen. O-16(alpha,alpha)O-16 resonant backscattering was cor rected and an absolute volume of oxygen concentration could be accurat ely estimated. Tilting the SiO2 films from the normal incidence allows an estimation of the film thickness and the composition. An irregular dependence between the oxygen signal height and the incident angle ha s been found from the result of grazing incidence. We have proposed a new method to estimate those compositions and film thicknesses at a ti me. This method is very simple and needs no correction with an ellipso meter. Moreover, it can be available to other oxide films.