In case the process margin of the device is large and the defect tendency in the wafer occurs randomly, process monitoring were possible using limited sampling measurement values. Previous 3D structure metrology equipment (CD-SEM, ellipsometry, etc.) are not able to measure the entire structure of the wafer due to the speed limit. If the measurement location does not include a weak point, an error occurs in predicting the wafer defect rate. In this study, we propose a new method that can extract weak points from color maps obtained by high-speed inspection tools that can measure the entire wafer. We were able to reduce the process error by about 20% by weak point monitoring.
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