Are there any standard qualification/acceptance requirements for immersion tin board finish? J-STD-003 calls out temp/humidity preconditioning followed by solderability testing which is similar to what we have in our (ancient) internal documents. Our requirements were written at a time when SnPb HASL was one of the few choices, but temp/humidity preconditioning doesn't seem appropriate for immersion tin. J-STD-003 even hints that it isn't appropriate for some finishes. HASL, OSP, and immersion silver do fine but immersion tin and, to a lesser degree, ENIG have trouble with solderability after this type of preconditioning.
Absent an industry standard method, what are other people using?
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