Hello,

I am encountering voids after reflow on several micro BGAs on one PCA
product. The voids that I've observed (with Xray) contribute to as high
as 60-70% of the joint area. My reflow profile was designed by running a
sample board with dummy components and thermalcouples attached right at
the joint. I also inspected the PCB lands and didn't see any via on pad.

Does anyone know the possible reasons for voids formation in BGA (micro)
reflow?

In general, in step by step how would one trouble shoot such a defect?

Rgds,
Peter