Life testing is reliability testing that operates units over time to observe failures and estimate lifetime characteristics - Test plans define sample size stress conditions and duration to derive hazard, survival, and confidence metrics.

What Is Life testing?

• Definition: Reliability testing that operates units over time to observe failures and estimate lifetime characteristics.
• Core Mechanism: Test plans define sample size stress conditions and duration to derive hazard, survival, and confidence metrics.
• Operational Scope: It is applied in semiconductor reliability engineering to improve lifetime prediction, screen design, and release confidence.
• Failure Modes: Weak test design can produce inconclusive results and poor decision support.

Why Life testing 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: Set statistically defensible plans and include failure-analysis feedback for model refinement.
• Validation: Monitor screen-capture rates, confidence-bound stability, and correlation with field outcomes.

Life testing is a core reliability engineering control for lifecycle and screening performance - It provides empirical evidence for reliability claims and risk assessment.