2025-11-11
We evaluated two contour-extraction approaches for metrology on high-voltage SEM images: CVNet, which integrates an Active Contour Model with deep learning, and a segmentation-based method using U-Net+FCN. Both methods were assessed using synthetic SEM images containing controlled noise, low contrast, multilayer overlap, and other SEM-specific artifacts. Performance was compared across multiple pattern geometries in terms of contour extraction, region segmentation, and overlay displacement sensitivity relevant to overlay and EPE measurements. U-Net+FCN achieved slightly higher overall accuracy, while CVNet showed stronger consistency between contour- and region-based metrics. Both methods exhibited comparable sensitivity for overlay displacement measurement.
Key words: High voltage, EBI, SEM, D2DB, CD, EPE, Overlay, CVNet