lot tracking

**Lot tracking** is the **end-to-end recording of each wafer lot's location, process history, status, and genealogy across the manufacturing lifecycle** - it provides the operational visibility required for quality control and delivery management. **What Is Lot tracking?** - **Definition**: Continuous monitoring of lot movement and process events from start to completion. - **Core Elements**: Route step, tool history, timestamps, holds, merges, splits, and ownership status. - **System Backbone**: Managed primarily through MES with interfaces to AMHS and equipment automation. - **Traceability Scope**: Includes parent-child genealogy when lots are split, merged, or reworked. **Why Lot tracking Matters** - **Quality Investigation**: Enables rapid backward and forward trace during excursions. - **Schedule Control**: Accurate lot status is essential for dispatch and due-date management. - **Compliance Assurance**: Supports auditable chain-of-custody for regulated and customer-critical products. - **Cycle-Time Reduction**: Eliminates time lost searching for lot location and state. - **Risk Containment**: Helps isolate affected product quickly during tool or material events. **How It Is Used in Practice** - **Event Capture**: Log every process and transport transition with precise timestamps. - **Genealogy Management**: Maintain explicit links for split, merge, and rework operations. - **Dashboard Control**: Provide real-time lot-location and risk-state visibility to operations teams. Lot tracking is **a fundamental digital control capability in semiconductor manufacturing** - accurate lot history and real-time location visibility are critical for quality assurance, planning accuracy, and rapid incident response.