Auger depth profiling data are presented for thin films of silicon oxide grown by thermal oxidation and for thin films of silicon nitride and silicon oxynitride deposited by low pressure chemical vapor deposition. Samples are bombarded by 500 eV argon ions, and Auger data is collected in either the N(E) or the dN/dE mode of operation. By probing the N, O, and Si(KLL) peaks a quantitative analysis of these films has been made.