Characterization of metal impurities in silicon-on-insulator material

Metal impurities in silicon-on-insulator material were characterized by total-reflection X-ray fluorescence spectroscopy (TXRFS). Wafers from different suppliers were analyzed. Surface concentrations of metallic impurities of the order of 10high11 qcm were found. Wafers representing single stages of the separation by implanted oxygen (SIMOX) fabrication were characterized. TXRFS data were compared with atomic absorption spectroscopy and secondary ion mass spectroscopy results.