Corrosion of PCB finished with organic
solderability preservative (OSP) proceeded by way of a uniform/pitting corrosion mechanism.
If there had been solder on the termination, the process parameters may have been correct, and problems with the pad
solderability may have been present.
Solderability Improvement of Obsolescence Electronic Components by Using Plasma Treatment Technique
Conventional organic
solderability preservative (OSP) finished PCBs were used as a reference.
This will eliminate oxidation, which harms
solderability. It also will add wetting and improve your technique.
When it was developed, the focus was on
solderability and compliance to environmental regulations.
The 1995/96 testing included
solderability testing in accordance with IPC J-STD-002, surface finish oxidation assessment using Sequential Electrochemical Analysis (SERA), and ball bond/ wedge bond wirebondability testing in accordance with the MIL-STD-883D, Method 2011.7, test condition C procedures.
Poor
solderability of the edge termination is typically caused by the lack of a protective coating like tin on the surface of the copper lead frame or resin smearing during component singulation.