Trace analysis for 300 mm wafers and processes with total reflection X-ray fluorescence

Total reflection X-ray fluorescence (TXRF) is essential for 300-mm silicon wafer production and fabrication of semiconductor devices. The 300-mm TXRF enables non-destructive contamination analysis on wafers for process development and process control. The TXRF system shows a very stable continuous operation, which allows accurate trace and ultra trace analysis on the silicon surface. It is equipped with two excitation sources covering the requirements of very sensitive measurement and wide element range. The TXRF is a key technology for contamination control during wafer reclaim. For this purpose we show that the system is able to examine the wafers during different processing states of reclaim. The system sensitivity is influenced by the surface of the wafer. For important processing steps, e.g. double side polishing, the sensitivity is as good as for measurements on hazefree polished wafers. We show with TXRF that cross-contamination with copper during double side polishing is suppressed.