Analysis of depth profile for impurity concentration in Si wafer by synchrotron radiation excited total reflection X-ray fluorescence spectroscopy

SR-TXRF spectroscopy is one of the powerful methods of measuring surface and near surface wafer contamination. To measure the depth profile of impurity concentration, Ni and Fe spin coated Si wafers and their annealed wafers have been measured by SR-TXRF. The depth profiles of impurity concentration are determined by comparing the angular dependence of fluorescence intensities calculated from possible models with measured intensities. These experiments are the applications of SR-TXRF angle scan for quantitative depth profiling of impurity concentration in the range of a few hundred angstrom depth without using any destructive method.