customer returns

**Customer Returns** in semiconductor manufacturing are **devices sent back by customers due to quality, reliability, or performance issues** — encompassing both warranty returns (covered by guarantee) and non-warranty returns (customer complaints, misuse, or field application issues). **Return Categories** - **DOA (Dead on Arrival)**: Device fails upon customer receipt — test escape from manufacturing. - **Early Life Failure**: Fails during initial customer testing or burn-in — latent manufacturing defect. - **Field Return**: Fails during actual end-use operation — reliability or application-induced failure. - **NTF (No Trouble Found)**: Device passes all re-tests — customer application issue, ESD damage, or intermittent failure. **Why It Matters** - **NTF Rate**: 30-50% of returns are often NTF — understanding NTF is important (application support, test coverage, intermittent issues). - **Tracking**: Returns are tracked as PPM (parts per million) per customer — key quality KPI. - **Relationship**: How returns are handled directly impacts customer relationships — rapid, transparent response builds trust. **Customer Returns** are **the voice of quality** — returned devices that reveal manufacturing, testing, or reliability gaps requiring corrective action.