Quantitative surface analysis of Fe-Ni alloy films by XPS, AES and SIMS

A comparison of quantitative surface analyses of Fe - Ni alloy thin films by various methods has been proposed as a pilot study by the Surface Analysis Working Group of the Consultative Committee for Amount of Substance (CCQM). To test the suitability of Fe-Ni for this purpose, alloy films with different compositions were grown on Si(IOO) wafers by ion-beam sputter deposition and the compositions were certified by an isotope dilution method using inductively coupled plasma-mass spectrometry. The alloy compositions measured with X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) using sensitivity factors determined from pure Fe and Ni metal films agreed with the certified mean values to better than 2%. The alloy compositions quantified by secondary ion mass spectrometry (SIMS) with a C60 ion source agreed to better than 4% with the certified compositions if one of the alloys was used to establish the relative sensitivity factors (RSFs). These results indicate that the quantification of the Fe - Ni alloy is a good method for a CCQM pilot study because matrix effects and ion-sputtering effects are small for these analytical methods.