semantic segmentation of defects
**Semantic Segmentation of Defects** is the **pixel-level classification of every pixel in a wafer or device image into defect categories** — assigning each pixel a label (scratch, particle, void, pattern defect, background) to create a complete defect map of the image.
**Key Architectures**
- **U-Net**: Encoder-decoder with skip connections — the workhorse for defect segmentation due to strong performance with limited data.
- **DeepLab v3+**: Atrous spatial pyramid pooling for multi-scale feature extraction.
- **SegFormer**: Transformer-based segmentation for capturing long-range spatial context.
- **PSPNet**: Pyramid pooling module aggregates context at different scales.
**Why It Matters**
- **Complete Map**: Every pixel is classified — no defects are missed (unlike object detection bounding boxes).
- **Precise Area**: Exact defect area calculation for severity assessment and yield impact analysis.
- **Multiple Classes**: Simultaneously segments multiple defect types in a single forward pass.
**Semantic Segmentation** is **painting every pixel with its identity** — creating complete, pixel-perfect defect maps for thorough wafer and device characterization.