lot number

**Lot number** is the **unique production identifier assigned to a group of units processed under common manufacturing conditions** - it is the backbone of semiconductor traceability and containment workflows. **What Is Lot number?** - **Definition**: Structured ID linking units to shared material batches, tools, and process windows. - **Hierarchy Role**: Often nested within wafer, strip, and unit-level identifiers. - **Data Integration**: Referenced across MES, test, reliability, and logistics systems. - **Usage Scope**: Appears on package marks, labels, and shipment documentation. **Why Lot number Matters** - **Containment Precision**: Enables targeted holds and recalls when defects are discovered. - **Root-Cause Analysis**: Connects field failures to exact manufacturing history. - **Compliance**: Traceability regulations often require lot-level record retention. - **Operational Visibility**: Improves production tracking and excursion response speed. - **Customer Confidence**: Reliable lot tracking supports transparent quality communication. **How It Is Used in Practice** - **ID Governance**: Define consistent lot-number format and uniqueness rules enterprise-wide. - **System Linking**: Synchronize lot IDs across assembly, test, and distribution databases. - **Audit Controls**: Run routine traceability drills to verify end-to-end lot lookup integrity. Lot number is **a fundamental control key in manufacturing quality systems** - robust lot-number governance is required for rapid and accurate problem containment.