accept/reject criteria

**Accept/reject criteria** is **predefined rules that determine pass or fail outcomes for reliability tests based on observed failures and confidence goals** - Criteria map statistical outcomes to actionable decisions such as release rework or redesign. **What Is Accept/reject criteria?** - **Definition**: Predefined rules that determine pass or fail outcomes for reliability tests based on observed failures and confidence goals. - **Core Mechanism**: Criteria map statistical outcomes to actionable decisions such as release rework or redesign. - **Operational Scope**: It is applied in semiconductor reliability engineering to improve lifetime prediction, screen design, and release confidence. - **Failure Modes**: Ambiguous criteria can create inconsistent decisions across teams and programs. **Why Accept/reject criteria Matters** - **Reliability Assurance**: Better methods improve confidence that shipped units meet lifecycle expectations. - **Decision Quality**: Statistical clarity supports defensible release, redesign, and warranty decisions. - **Cost Efficiency**: Optimized tests and screens reduce unnecessary stress time and avoidable scrap. - **Risk Reduction**: Early detection of weak units lowers field-return and service-impact risk. - **Operational Scalability**: Standardized methods support repeatable execution across products and fabs. **How It Is Used in Practice** - **Method Selection**: Choose approach based on failure mechanism maturity, confidence targets, and production constraints. - **Calibration**: Document criteria before testing and verify decision consistency with independent review. - **Validation**: Monitor screen-capture rates, confidence-bound stability, and correlation with field outcomes. Accept/reject criteria is **a core reliability engineering control for lifecycle and screening performance** - It enforces disciplined and reproducible reliability governance.