edge rounding

**Edge Rounding** is a wafer finishing process that smooths sharp corners at the wafer edge to reduce chipping, particle generation, and film stress during processing. ## What Is Edge Rounding? - **Method**: Chemical-mechanical polishing or wet etching of wafer bevel - **Profile**: Transitions sharp 90° corner to rounded ~45° bevel - **Timing**: After wafer slicing, before device processing - **Specification**: Typically 200-400μm radius ## Why Edge Rounding Matters Sharp wafer edges concentrate mechanical stress, leading to chips that contaminate entire lots. Rounded edges reduce breakage by 50%+ during handling. ```svg ``` **Edge Rounding Benefits**: - Reduced edge chipping during robot handling - Better epitaxial film uniformity at edge - Reduced particle generation during CMP - Lower film stress at wafer periphery - Fewer handling-related scratches