Simultaneous nuclear microanalysis of nitrogen and oxygen on silicon

The quantitative evaluation, by means of nuclear techniques, of some light elements on medium or light matrices is often complicated by the interference of the signal produced by different nuclei. The measure of the oxygen and nitrogen content on silicon thin film devices is a problem frequently encountered in semiconductor technology. This paper shows that the use of 16O(d, p0)17O and of 14N(d, p5)15N nuclear reactions in the deuteron energy range 0.55 - 0.62 MeV allows the simultaneous microanalysis of oxygen and nitrogen on silicon. From the measured cross-sections it turns out that sample thicknesses up to about 40 keV can be analyzed with an overall accuracy of 5% without the need of any correction by using 0.61 MeV deuteron beams. Moreover the trend of the 16O(d, p0)17O nuclear reaction cross-section also allows qualitative information on the oxygen distribution into the film to be obtained. (orig.)