Electronics Forum | Thu Apr 11 00:54:49 EDT 2019 | SMTA-Vikram
Yes, we have try different Flux, probes. etc... also not to paste vs Paste Via, but still we have ~3% NDF due to contact issue. I am looking for selective pasting with less flux dispenser.Any idea or anyone has used? What about plug via before pas
Electronics Forum | Thu Oct 06 12:18:31 EDT 2016 | davef
Looks like moisture bubbling out of the board. I doubt that your baking at 60*C for a half hour is going to do very much to dewet the board. 60*C is warm to the touch, that's it!!! Water boils at 100*C. 60*C is the temperature of a cup of Dunkin. Cr
Electronics Forum | Wed Mar 25 16:38:21 EST 1998 | Steve Joy
We have successfully put .016" vias in .030" pads. There is no issue with .030" solder balls, since the actual volume of the .002" via in pad is small compared to the ball+solder paste volume. We did notice random bubbles where, apparently, the sol
Electronics Forum | Wed Mar 25 19:41:01 EST 1998 | Earl Moon
| We have successfully put .016" vias in .030" pads. | There is no drain off with .030" solder balls, since | the actual volume in the .002" depression is low. | We did notice random bubbles where, apparently, the | solder reflowed and trapped the a
Electronics Forum | Wed Nov 12 22:34:30 EST 2008 | davef
How about plugging the via with a temporary solder mask or coving them with thermal tape?
Electronics Forum | Fri Dec 01 13:30:08 EST 2017 | kojotssss
Stencil thickness is 4 mil. Via's are plugging from bottom. Gas may be developed under the component? Take Reflow Ovens Thermal Profiling changes? In your opinion?
Electronics Forum | Fri Dec 13 12:10:36 EST 2002 | STEPHEN WALTERS
WE ARE EXPERENCING OPEN 8 MILL VIAS UNDER THE BGA'S, THEY ARE OPENING AFTER THE ASSEMBLY PROCESS, THEY ARE FROM MULTIPLE PCB VENDORS, THEY PASS AT THE PCB SUPPLIERS TESTING, AND WE HAVE FOUND THAT THEY HAVE HAD 2 MAJOR CAUSES 1. BUBBLE INTRAPMENT, 2.
Electronics Forum | Wed Feb 16 21:51:29 EST 2000 | Dave F
Kurt: Lots of choices, not many of them good, yano. 1 So LPI has taken over the market pretty nearly 100%, but it won't "tent" reliably, because it is not very viscous when applied and drops into the hole. So then, tenting/plugging with LPI is bad
Electronics Forum | Wed Feb 16 21:51:29 EST 2000 | Dave F
Kurt: Lots of choices, not many of them good, yano. 1 So LPI has taken over the market pretty nearly 100%, but it won't "tent" reliably, because it is not very viscous when applied and drops into the hole. So then, tenting/plugging with LPI is bad
Electronics Forum | Wed Apr 09 09:48:49 EDT 2003 | iman
after oven bake dry the PCB, we process within 4-hrs, else need to rebake again under same baking parameter. taking a look, the exact pads with the blowholes are full ENIG pads with no via holes under the solder-intend land areas. In event there is
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