Stress Factor
Environmental stress testing procedures apply elevated ambient temperature and voltage bias to induce early component failures before deployment. Burn-in acceleration compresses the infant mortality phase of semiconductor and sensor packages into a brief screening interval. Arrhenius activation energy models govern the thermal stress ratio, while voltage acceleration models scale the electric field exposure across thin dielectric layers.
Qualification protocols define the activation energy parameter for target failure mechanisms such as electromigration or gate oxide breakdown. This screening method stops at the boundary where physical failure mechanisms shift from latent defects to wear-out modes.
Screening Acceleration
Thermal chambers maintain ambient temperatures near maximum junction limits while applying electrical bias across all sensor functional nodes. Higher temperature accelerates ionic contamination migration and intermetallic compound growth within bond wire interfaces. Voltage stress beyond nominal operating thresholds accelerates oxide breakdown without exceeding thermal runaway limits.
Screen duration depends on the calculated acceleration factor derived from pre-qualification step-stress testing.
Failure Rate
Degradation tracking during thermal stress identifies latent manufacturing defects.
Verification Limit
Post-screening electrical testing measures zero-point drift and sensitivity change against initial baseline values. Sensors exceeding drift thresholds during post-burn-in verification are isolated prior to board-level integration. Standard qualification procedures enforce strict limits on acceptable parametric shifts.
Calibration factors established before thermal stress require re-verification when burn-in alters internal resistor values or junction voltages.
