If you have been hoping that you current BGA process doesn’t fall victim to non-wets, it’s time to gain confidence. It sounds like you need a ball attach flux that is powerful. Those old solderability tests that define a flux’s wetting characteristics are done on clean copper. If you’re like the rest of the industry, I doubt you are using bare copper pads on your substrates. We know what works with different alloys on many various surfaces including Au/Sn, OSP, and Nickel (to name a few). Stop worrying about the flux you are using and give me a call @ (315) 853-4900 x7592.
Authored by previous Indium Application Manager Jim Hisert