Quantitative surface chemical analysis of AuCu alloys with XPS

The work of VAMAS‐SCA project no. 25 is reported. The project was an XPS round robin with thgree different compositions of AuCu alloys (Au 25 at.%,–Cu 75 at.%, Au 50 at.%–Cu 50 at.%, Au 75 at.%–Cu 50 at.%.). These alloys were alson the subject of an earlier AES round robin ( VASMAS‐SCA project no. 17). Pure gold and pure copper was used as the standard materials. By using peak areas of the Au 4f doublet and Cu 2p 3/2 for the calculation, the effects of measurement conditions and data processing on quantification were examined. The reliability of quantification by three methods, namely the ‘relative sensitivity factors’ method, the ‘pure metals as standard materials’ method and the ‘alloy as standard material’ method, was compared. It is concluded that measurement conditions such as photoelectron emission angle and energy resolution did not affect quantification and that there was no effect of the different background subtraction methods on quantification. With the ‘alloy as standard material’ method, variations of the measured surface concentrations were the smallest, namely ∼2–6%.