In this work a systematic comparison of total reflection X-ray fluorescence (TXRF), synchrotron radiation-TXRF (SR-TXRF), time of flight secondary ion mass spectroscopy, lifetime, and deep level transient spectroscopy data of iron concentration is carried out. SR-TXRF is considered as a reference for the other techniques. Reasonably good correlations are obtained, though, as expected, SR-TXRF exhibits the maximum sensitivity among surface techniques. Among lifetime measurements, the electrolytic metal analysis tool (ELYMAT) technique shows the best sensitivity at very low concentrations. A method is developed to elaborate ELYMAT data in order to quantify iron concentration when more contaminants are simultaneously present. (C) 2004 The Electrochemical Society.