setup time

**Setup time** is the **elapsed time required to prepare a tool for the next product, recipe, or configuration after completing a prior run** - it is a major contributor to capacity loss in mixed-product manufacturing. **What Is Setup time?** - **Definition**: Changeover duration including recipe load, hardware change, purge, verification, and first-pass checks. - **Trigger Context**: Occurs during product mix switches, process variant changes, or lot family transitions. - **Loss Characteristic**: Setup consumes available tool time without producing sellable wafers. - **Reduction Methods**: Standard work, offline prep, and SMED-style internal-to-external task conversion. **Why Setup time Matters** - **Capacity Impact**: Frequent long setups can materially reduce weekly output. - **Cycle-Time Effect**: Queue growth increases when setup windows block dispatch. - **Cost Burden**: Higher setup share raises cost per wafer for high-mix products. - **Scheduling Complexity**: Setup-sensitive tools require smarter sequencing to protect throughput. - **Flexibility Tradeoff**: Setup performance determines economic feasibility of diverse product mix. **How It Is Used in Practice** - **Task Mapping**: Decompose setup into elemental steps and identify avoidable delay points. - **Sequence Optimization**: Group lots to minimize changeover frequency without hurting commitments. - **Standardization**: Use checklists, kitting, and pre-stage workflows to shorten repeat setups. Setup time is **a key lever in high-mix fab productivity** - reducing changeover losses increases effective capacity without additional equipment spend.