A depth profile fitting model for a commercial total reflection X-ray fluorescence spectrometer

We have proposed a practical depth profiling model for a commercial Total Reflection X-Ray Fluorescence (TXRF) spectrometry instrument. The model includes three factors peculiar to a commercial TXRF instrument: (a) the irradiated X-ray photon density on the sample surface depends on a glancing angle, (b) the X-ray irradiated area becomes smaller than the detector view over a certain glancing angle, and (c) the incident X-ray has angular divergence. This model was optimized by comparing the measured Si-K alpha for a silicon wafer with the calculated one. The results indicated that all of the three factors are indispensable for our instrument. We have applied this model to a surface contaminant and discussed its adequacy. (C) 1997 Elsevier Science B.V.