Electronics Forum | Tue Feb 13 15:20:12 EST 2007 | billyd
Fellas: I'm having a tough time with voiding with my lead free water soluble paste under my large BGAs. I know some is almost inevitable, but this is more than I'd like. This is with a slope of .9, soak of 60 seconds, above 217 for 85 seco
Electronics Forum | Wed Sep 01 05:29:40 EDT 2010 | arjan
We baked the parts just before assembly. 2>we baked the parts and store them in 4 days in drycab (60degC, Rh0,5%)and finally assembly 3> we baked the parts and refowed them on a leadfree profile and finally the assembly on the boards. The same we als
Electronics Forum | Thu Jun 02 08:42:06 EDT 2016 | emeto
Several important things to watch. 1. More paste can result in more voiding(I usually shoot for 50-65% coverage) 2. Make a different grid(windowpane) for you pad - try with more smaller windows 3. Try both ramp to spike or Soak profiles and see whic
Electronics Forum | Thu May 09 08:36:18 EDT 2019 | solderkingchris
Hi, You can work on improving stencil design, having the perfect profile and other process improvements but it may be the paste itself letting you down. We have put a lot of work into developing our solder pastes to significantly reduce voiding. Y
Electronics Forum | Tue May 07 10:36:38 EDT 2019 | slthomas
Probably just means you started out with an optimal profile. I suspect that not everyone does. ;) It seems like we did have some luck with profile adjustments in one instance with some QFN's with a large thermal pad. Like I said, though, the profi
Electronics Forum | Wed Jan 19 00:42:09 EST 2000 | park kyung sam
In my case, when i solderd the bga in normal reflow(convection hot air). There is a lot of boid. i had tried to reduce void long time. so i reduced just a little. It did't satisfied me but now i cannot looking for the void in soldered bga i
Electronics Forum | Fri May 21 10:16:31 EDT 1999 | Parvez
Dave, i tried reflowing bare boards with only solder printed on em and no component placed. we still got voids as same as when components were placed. so atleast one of that theories(voids due to component/component placement)could be considered to b
Electronics Forum | Mon Nov 25 22:08:05 EST 2002 | Ben
Thanks for the advise. I got the advise from my solder paste vendor to increase the time above melting point for flux outglassing to escape. I tried but no big help. For the moisture issue, actually I've try to bake both the PCB and components at 12
Electronics Forum | Wed Apr 16 10:45:16 EDT 2003 | Takfire
Recent cross-section analysis for a customer complaint revealed voiding in the solder fillet. In some cases, the remains of outgassing were also observed. During the failure analysis, we also observed failures where the solder fillet wicked on the
Electronics Forum | Sat Mar 06 06:15:14 EST 2004 | Bryan
Thanks Tommy. In fact I've tried many types of profile,but it didn't work.I'll try to make the peak temp. as low as 205C and dwell long as in some threads Dave said.I've tried baking the BGA and PCB before mounting also dindn't work.yes,I've heard th
