Electronics Forum | Thu Dec 21 13:33:46 EST 2006 | ppcbs
The problem with super glue is that is has a cyanide base that turns into a toxic gas and evaporates when heated. See IPC-7095. Via's should be fully plugged with solder mask at the fab house. If your PCB designers are not up to speed on IPC requi
Electronics Forum | Fri Dec 22 07:11:32 EST 2006 | billyd
Wait a second... 10 to 15 mils at toe end. How are you doing that? See, the ones we did have a bit of a time with had no catellations on the outside. So, it's like a BGA in that regard. All your paste goes under the part, so if it's not even, or if i
Electronics Forum | Wed Jan 24 10:20:39 EST 2007 | electronhose
Seriously, OSP?, change the board finish, you are the OEM, correct? You have the power! Also, as another poster mentioned, high force applied at ICT ( possibily to cut through the OSP goop ?!? ) could be warping the board enough to crack the joints.
Electronics Forum | Wed May 02 11:00:46 EDT 2007 | bartlozie
to get a 0-defect layout, OEM and CM have to work together, If you know what connections (balls) are the problem ones, let me know, and send me the gerber-layers + solderpaste layer, so we can see if the problem is design related or if you CM realy
Electronics Forum | Wed Jan 17 07:55:11 EST 2007 | pavel_murtishev
Vladimir, Phil J is right. Tantalum�s moisture vapor outgassing is the root of the problem you are searching for. Internal pressure of entrapped moisture becomes very high in reflow zone. Vapor jet shifts your components and affects BGA�s bumps. Bak
Electronics Forum | Wed Jan 17 17:09:43 EST 2007 | russ
appears to be incomplete reflow on a couple of balls or they were moved during a cooldown. it also seems as though there is a deviation in ball size due to inconsistant paste application possibly. I would stop applying paste and just reflow that pa
Electronics Forum | Thu Jan 18 13:13:53 EST 2007 | russ
won;t recommend a paste since I propose that you do not use but here is a flux I have had great success with Indium tacflux 20B IPN 84283 No clean flux, Use this alone without paste and your BGAs will work!! What was your package temp during th
Electronics Forum | Thu Jan 25 04:11:09 EST 2007 | aj
Tricky stuff. I would expect to hit between 210-215 peak temp on Lead process. What sort of profile are you using? I would imagine a good soak zone would be critical- I have never had BGAs on bottomside so cant really advise any further,i will be in
Electronics Forum | Tue Jan 30 03:44:17 EST 2007 | frank63
Thank you for feedback and comment. We are trying this again, increasement of solder temp to reach 210-215 peak temp. This is also our norml guideline, but in the past the colleagues had observed problem with that PCB, so reduced it. I let you kno
Electronics Forum | Tue Jan 30 09:31:08 EST 2007 | russ
these assemblies getting depaneled? ICT? any fixtures or anything? I would check your print and placement equipment and make sure there are no support issues as well. But I believe you mentioned fractures so that would be happening after the reflow
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