Reballing Fusion IC

[trunks81]

Hello

Ive an problem reballing this IC there are multiple pads are corroded,
And solder is not sticking to it.
How do i activate those pads again ?
Tried flux that gives no succes.

[momaka]

Re: Reballing Fusion IC

Could you post a picture of the IC, and more specifically of the corroded pads, if possible?
Also, are you sure the pads weren't ripped off? If that's the case, the spot where the pad was will look like a brown spot and solder won't stick to it. If that's the case, the IC is likely done for. Otherwise, if you are sure the pad is still there, clean area well with 99% or higher IPA, then use a small sharp flat-heat screwdriver (or similar sharp object) and clean the pad by scratching it and exposing the copper on the bottom. Once exposed, put flux and tin the pad with a soldering iron. Then clean with wick, then clean with IPA, then try reballing that pad/area again.

That aside, what brand of flux are you using and where did you buy it?
So cheap rosin fluxes can really burn up and make it hard for solder to stick to afterwards, so that's why I'm asking.