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Contamination

Under-Part Ionic Leakage

A geometry-dependent leakage example under a mounted part, showing how some contamination failures are real even when the image is not visually dramatic.

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Scale 10 um scale shown
Observed feature Under-part geometry with a likely leakage-relevant region between conductive features
Likely mechanism Ionic electrical leakage between pin 5 and the center pad under the mounted part
Under-part conductive geometry associated with an ionic leakage path

Interpretation

Why this image matters

The report concluded that the device most likely failed due to ionic electrical leakage between pin 5 and the center pad under the part as mounted on the PCBA. It also noted that the condition was bake recoverable and that ESD was not supported as the cause.

This image is a reminder that some contamination-driven failures are highly geometry dependent and may not produce a dramatic standalone visual signature.

It works best as a context-rich leakage example rather than as a pure morphology image.

ionic-contamination leakage under-part geometry-dependent
Use this when

Best comparison value

  • Teaching under-part leakage paths that depend on geometry and spacing
  • Explaining bake-recoverable contamination failures
  • Contrasting contamination-driven leakage with ESD claims
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