Failure Analysis by External Lab

Hi All..

I need your advice, when you send your boards to be analized by external lab, what kind of result would you expect from them? Do you expect them to find the root cause of the problem and give countermeasure of the problem? (this is what I expect)

History: We have an issue on our board, which we assume it is Black Pad (or any other PCB manufacturing failure). And we send some samples to external lab to analize the root cause. The problem is, their test is not suitable for confirming a black pad (I think). Because they only do a cross section & SEM with 200x. While based on some papers I read, should be SEM with 7000x. They also do FTIR which result is not conclusive (we didnt ever understand the meaning)

"Based on the FTIR results, the closest matching of "PCB Surface" and the "BGA Surface" to the FTIR library is 2,4-diaminopurine hemisulfate hydrate and 2,6-diamino-8-purinol hemisulfate hydrate with 83.4% and 69.0% matching respectively. Spectral matching between "PCB surface" and "BGA surface" is 77.99%"

Seems they only lending us their machine to do the test, but not analyzing the problem.

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