Does anyone have any comments to this issue below.  This condition was
occurring after boards were reflowed.  Any comments would be appreciated.

The SEM/EDS analysis of the PCB revealed that the "solder ball" - like
features found on the pads should be considered as "footprints" of solder
balls. They are relatively flat (not bump-like), up to 150 mm in diameter
and enriched with such elements as Sn, Pb and C.   These bumps are occurring
after reflow.  A trial was conducted where bare boards where reflowed and
the same phenomena occurred.  Here are the process/board conditions:

Profile for top and bottom is 90 110 130 155 175 195 250        Belt
speed : 28 inch/min
*       No nitrogen in the oven
*       Solder paste is NC251 Sn63Pb37 from AIM
*       Material is polycad FR226 0.457mm 0.50Z./0.50Z copper, plated to 10Z



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