saw street

The **saw street** (also called **scribe lane** or **kerf region**) is the narrow strip of space intentionally left between adjacent dies on a semiconductor wafer. This area is reserved specifically for the **dicing blade** or **laser** to cut through when separating individual chips after wafer-level processing is complete. **Key Characteristics** - **Typical Width**: Ranges from about **30 µm to 200 µm**, depending on the dicing method — laser dicing allows narrower streets than traditional blade dicing. - **Contents**: Saw streets often contain **test structures**, **alignment marks**, **process control monitors (PCMs)**, and **dummy fill patterns** used during fabrication but not part of the final die. - **Impact on Yield**: Narrower saw streets mean more usable die area per wafer, directly improving **die per wafer (DPW)** and overall economics. Advanced fabs continuously work to shrink kerf width. **Why It Matters** If saw streets are too narrow, the dicing blade can **damage active circuitry** on adjacent dies, causing yield loss. If too wide, valuable wafer real estate is wasted. Optimizing saw street width is a balance between **mechanical reliability** during dicing, the space needed for **process monitors**, and maximizing the number of good dies per wafer.