Analysis of surface cleanliness on silicon wafers using total reflection XRF excited by synchrotron radiation

The monitoring of surface cleanliness of silicon waters is very important. Total Reflection X-ray Fluorescence is expected to be highly sensitive for the ultra trace contaminants on the top surface. Synchrotron radiation is an appropriate X-ray source. This method was applied to relatively heavy elements such as Cr, Fe, Ni, Zn, which were suffused on silicon wafer surfaces by spin coating technique. Thie method has been found to have high quantitativeness and its minimum detection limits for those elements was found to be the order of 1011 atoms/cm2. And this method was also found to be applicable to the real samples in the course of cleaning. (author)