setup wafers

**Setup Wafers** are **non-product wafers used to verify tool alignment, recipe parameters, and equipment readiness before processing product wafers** — confirming that the tool is correctly configured and producing expected results before committing valuable product material. **Setup Wafer Uses** - **Alignment Verification**: Lithography tool alignment (baseline correction, lens calibration) using setup wafers with alignment marks. - **Recipe Verification**: Run a test wafer with the production recipe — verify output (CD, thickness, etch depth) matches specifications. - **Dummy Wafers**: Fill empty slots in a cassette — ensure uniform gas flow and temperature across the batch. - **Send-Ahead**: A wafer processed one step ahead of the lot — verify the next process step is ready. **Why It Matters** - **Prevention**: Better to detect a problem on a setup wafer than on 25 product wafers — setup wafers protect production. - **Productivity**: Setup wafers consume capacity — efficient setup procedures minimize the overhead. - **Automation**: Automated setup verification can reduce setup wafer consumption. **Setup Wafers** are **the test shots before production** — verifying tool readiness and recipe correctness before committing product wafers to processing.