Electronics Forum | Tue Nov 27 14:24:13 EST 2001 | mparker
Short term fixes can be: have the vias "plugged" with solder by the fab house. This works if your fab is HASL finish. Tent the vias with solder mask, top side only. You may get a flux entrapment issue in the vias with this manner. Long term fix can
Electronics Forum | Mon Apr 22 15:05:47 EDT 2002 | tim_easterling
Depending on the volume of boards you are manufacturing, the most cost effective solution would be to epoxy plug the vias prior to LPI soldermask application. The technique is common practice and most suppliers can provide it will little or no cost a
Electronics Forum | Mon Oct 21 19:17:23 EDT 2013 | hegemon
The first picture shows an issue. Note that the vias adjacent to the interior rows are filled with solder. At the outside rows this is not evident. What you might have are interior spheres that are smaller in volume than the rows on the outide, si
Electronics Forum | Mon Jul 26 18:05:18 EDT 1999 | ScottM
| Presently protos of micro-bgas (80i/o) pitch .030/.031 | 12BGA per assembly | | The board is a (.062, 4 layers) FR-4 using Dry film | Pads .014inch | Vias within footprint .020inch | Vias to be filled by bottom side(solder side) only .030in dia. F
Electronics Forum | Thu Oct 28 15:53:27 EDT 2010 | dwonch
Ok, just to put closure on things I figured I should post the conclusion of this whole ordeal. We've acquired a new BGA rework station that allows us to get away without tenting our vias under the BGAs. This allowed us to change our PCB spec to rem
Electronics Forum | Wed Feb 16 09:33:09 EST 2000 | Kurt Waskow
Interested in information regarding PCB soldermask tenting over vias within a BGA layout. Is this a common practice to reduce the occurrence of shorts, are there any reliability concerns? Thanks!
Electronics Forum | Mon Feb 21 08:33:53 EST 2000 | Tony Di Mauro
Kurt, When I was working in a captive manufacturing house we had been to migrate toward tenting all vias under the BGA to eliminate not only shorts but insufficient (Starved) joints. Tony
Electronics Forum | Wed Feb 16 09:33:09 EST 2000 | Kurt Waskow
Interested in information regarding PCB soldermask tenting over vias within a BGA layout. Is this a common practice to reduce the occurrence of shorts, are there any reliability concerns? Thanks!
Electronics Forum | Mon Feb 21 08:33:53 EST 2000 | Tony Di Mauro
Kurt, When I was working in a captive manufacturing house we had been to migrate toward tenting all vias under the BGA to eliminate not only shorts but insufficient (Starved) joints. Tony
Electronics Forum | Fri Nov 22 05:04:07 EST 2019 | SMTA-Matthew
We have some circuit boards where the solder mask seems clear instead of green on top of some of the tented via pads. No gold deposited during the ENiG process and no solder sticks to it but why is it clear and does it have any correlation to the thi