A general procedure for extracting quantitative depth information from take-off-angle-resolved XPS and AES

An evaluation procedure is described for determination of the ultra-shallow depth composition of technological surfaces from angle-resolved intensity measurements of X-ray photoelectrons and Auger electrons which overcomes major deficiencies of several other procedures. Essentially, experimental data are compared to generalized model calculations such that the procedure is fully interactive at all stages of evaluation and that complete transparency of data treatment is maintained. The use of intensity self-ratios allows data to be ranked according to significance and quality and a realistic error analysis to be made. The use of supplementary information about the specimen and its treatment is encouraged to compensate for the inherent insufficiency of (all) angle-resolved data for surface reconstruction. The procedure can serve as a source of input data for the testing of less transparent procedures.