Preserve Sample Identity Through Destructive PCB Analysis

Destructive analysis can turn one clearly labeled assembly into several small specimens whose origins are easy to confuse. Plan the identity scheme before cutting, sectioning, or removing components. The final image is only useful if another reviewer can locate its specimen in the original board and understand how it was prepared.

Create the parent record first

Photograph both board sides and record assembly revision, serial identity, reported failure, prior tests, and any rework. Mark the proposed analysis locations on a drawing or annotated image. Preserve orientation using unambiguous physical references rather than a handwritten arrow whose meaning disappears after cutting.

TI’s failure-analysis overview includes destructive physical analysis among the available techniques. Because these methods alter the specimen, the practical handling plan should establish what evidence must be captured first and what material will remain afterward.

Assign child identities at each operation

Keep each image and measurement associated with the specimen identity and preparation stage. The microsection-report review helps determine whether a polished plane actually intersects the feature relevant to the question. A nearby section is not automatically evidence of the failed location.

Preserve options for follow-up work

For example, cutting through the only suspected joint may consume evidence needed for another technique. Agree the sequence with the analyst before the first irreversible operation, using the evidence-preservation plan. Identify any hold point where new observations should determine the next step.

Document material lost during preparation and any uncertainty in the plane or location. Do not infer continuity across an unexamined gap simply because two images appear adjacent in the report. If the analyst changes the intended preparation route, retain the reason and updated specimen map.

End with a remnant inventory and disposition agreement. A report should distinguish what was observed, what was consumed, and what remains available for review. This prevents later requests for confirmation from depending on a specimen that no longer exists or cannot be identified.