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 | Fri Oct 29 11:42:04 EDT 2010 | pfloh
For my opinion, this will not the end for you yet if supplier unable to provide you the rootcauses and corrections. I faced this more than 3 times within 2 years. All type of lab tests (SEM, FTIR,cross-sectioning,solderability tests, and etc.) They
Electronics Forum | Sat Apr 17 10:44:21 EDT 2010 | kcorrin
Sounds like you and your board suppliers have done alot of work with this issue trying to solve the problem. When I got into this situation previously, I relied on an outside lab to help me. We didn't have SEM or any testing capability at my shop eit
Electronics Forum | Mon Apr 19 15:45:21 EDT 2010 | dwonch
Thanks to all for your input. We did have a third party do an analysis on boards from the first shop. They were shipped directly from the board shop to eliminate the possibility that we could contaminate them. The third party (Forsite) did find Sili
Electronics Forum | Mon Apr 19 10:52:05 EDT 2010 | esca
Hi, if you want to verify the gold contamination, is mandatory to use the XPS and FTIR analysis, but is difficult think about a gold contamination from 3 different manufacturers. Do you have cleaned the PCBs after an erroneous screen process ? If no
Electronics Forum | Mon Apr 19 11:04:21 EDT 2010 | baildl632
We have had some unusual reflow conditions with BGA's as well. We did not come to the conclusion that something was covering the lands though. It typically occured with only the BGA lands (not the decoupling caps on the back side). We found that the
Electronics Forum | Thu May 06 13:06:36 EDT 2010 | dwonch
Unfortunately nothing ground breaking to report. The board shops analysis (SEM/EDS)showed high levels of carbon and oxygen, likely indicating an organic based contaminate. They are still stumped on where it is coming from. We recieved some boards y
Electronics Forum | Fri Apr 23 13:00:35 EDT 2010 | dwonch
Hi all, The board shop finally got back to me with some results. They did find residue present on some of the pads. They have sent a board out for evaluation to learn what it is. Hopefully from that we can determine the root cause. The good news i
Electronics Forum | Mon Apr 19 11:26:32 EDT 2010 | davef
Independent Labs * American Competitiveness Institute; One International Plaza Suite 600, Philadelphia, PA 19113; 610-362-1200 F1290 info@aciusa.org * Bodycote Materials Testing , 847-676-2100, na.bodycote-mt.com * Foresite 765-457-8095, http://www
Electronics Forum | Fri May 07 09:25:55 EDT 2010 | dwonch
Yes, the vias under the BGAs are the only ones capped. I tend to agree with you that the leaching should affect the bottom more than the top and that was actually the case with the two previous shops that had this problem. We suspected with those s
