Case 1129 ยท Public preview
Fabrication Damage to a MnO2 Layer Can Channel Current into Destructive Hot Spots
Solid tantalum capacitors from suspect lots exhibited elevated failure rates and localized thermal damage involving the tantalum slug and manganese-dioxide cathode layer.
SEMEDSElemental mappingMetallographic sectioningFailed-to-stock and control comparison
What the evidence preview establishes
An anomalous fabrication condition damaged the MnO2 deposit before completion of the capacitor structure, increasing the probability of current channeling and destructive hot-spot formation.
Why this case matters
A tantalum-capacitor burn site may be the endpoint rather than the origin. Examine unfailed stock parts and deposition-layer sequence to determine whether pre-existing MnO2 damage created narrow current paths before the visible thermal event.
Full evidence reserved for MEMBER and STOREThe complete case includes the evidence sequence, four interpreted figures, alternative explanations, limitations, and practical application guidance.