Silicon Wafer Cleaning Processes Monitoring by the Surface Charge Profiler Method

摘要

The high sensitivity of the SCP method to traces of metallic contamination on silicon wafers is used for the control of cleaning steps. Feasibility of in-line, non-invasive, straightforward monitoring using production wafers is demonstrated. Specific protocol of measurement allows the use of surface recombination lifetime as sensitive parameter for detection of surface contamination, with sensitivity as low as a few 10~9 at/cm~2.