A STANDARD SAMPLE PREPARATION METHOD FOR THE DETERMINATION OF METAL IMPURITIES ON A SILICON-WAFER BY TOTAL-REFLECTION X-RAY-FLUORESCENCE SPECTROMETRY

Total reflection X-ray fluorescence spectrometry (TXRF) is widely used for the determination of surface metal contamination on a silicon waf er. In TXRF measurements, calibration standard samples are needed to q uantify the metal concentration. We propose a new method for the prepa ration of calibration standard samples for TXRF. The method is called ''Immersion in Alkaline Hydrogen Peroxide Solution (IAP)'', in which t he silicon wafers are immersed in an intentionally contaminated alkali ne hydrogen peroxide solution. Samples made by the IAP method are suit able calibration standard samples for TXRF because of their good depth profile reproducibility and good uniformity on the surface as well as homogeneity in a given batch. They can also be applied for making a c ross-check among plural TXRF instruments as well as among different an alytical methods.