Stress Baseline
Reliability engineering methods designed to eliminate early-life defects in electronic hardware modify failure distribution timelines during manufacturing. Burn-in screening procedures rely on infant mortality curve shaping to accelerate latent manufacturing defects into early failures prior to product shipment. This practice applies elevated thermal and electrical stress profiles to electronic assemblies, shifting the bathtub curve’s initial high-failure rate phase into the factory environment.
The scope applies strictly to early manufacturing screening and excludes end-of-life wear-out degradation mechanisms.
Failure Acceleration
Failure acceleration relies on Arrhenius rate equations and inverse power laws to calculate accelerated stress factors. Applying elevated voltage and temperature stress during functional screening forces latent defects, such as cold solder joints or contaminated trace gaps, to fail rapidly. Care must be taken so stress levels do not induce false failure modes unrepresentative of operational field conditions.
Continuous monitoring during stress cycles captures intermittent shorts or open circuits as they occur.
Screening Margin
Screening margin determination balances defect extraction against total test duration and thermal degradation of good components. Quality protocols evaluate yield data from screening runs to shorten or lengthen burn-in duration based on defect arrival rates. The process ends when failure rates decay to a stable, acceptable baseline.
