Good Morning,
I have been struggling with this part for some time now. I have to agree that whoever designed this part, did not have to manufacture with it. We have advanced to a point where they have a acceptable yield but I believe that will be highly dependent on the application. This is what we found: Manufacturer recommends 1:1 stencil with a .005" foil. We tried 1:1 with excessive bridging. Knee jerk reaction, we cut a new stencil with a 30% reduction. No voids but the solder would columnize between the PCB and part. We cut a new stencil to a 15% reduction and we saw a decrease in bridging and full wetting of the pads. We found that this part was prone to voiding. We also found that after the reduction, any bridge found was associated to a pad with a large void (displacement of the solder)
Rework: We purchased a component print frame stencil. We stencil the part, reflow the solder on the part, and then place it like a BGA. So far we have a 100% success rate
So reduce your stencil slightly, adjust your profile to minimize voids For rework, pre-bump your parts with a component print frame then replace.
Is this a high volume application? If not, I would reduce the paste volume deposited on the PCB and bump the parts from the begining.
Anyway, my $.02
Good Luck
Chris
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