Electronics Forum | Fri Aug 22 09:49:31 EDT 2003 | davef
Ask your supplier for a corrective active and failure analysis of the boards. In parallel, send the boards to a failure analysis laboratory to determine the material on your gold pads. Take your work to another supplier.
Electronics Forum | Thu May 05 11:50:03 EDT 2005 | russ
Just went through this with a customer. Removed BGAs and noticed discolered pads at some locations. It was determined that these were open connections that had some type of flux migration between the ball. They also took solder readily. This may
Electronics Forum | Thu May 05 12:22:01 EDT 2005 | jimmiem
could there have been a solderablity issue with that pad to begin with, allowing the flux in (from improper cleaning of adjacent work) to expadite an error may have happened later down the road?
Electronics Forum | Thu Aug 21 20:39:09 EDT 2003 | davef
You have one option: Take the boards to the fabricator that build the board and ask him for $20k.
Electronics Forum | Thu May 05 12:00:16 EDT 2005 | russ
Bad cleaning practice is suspect. It is believed that W.S. flux was used to solder adjacent components and then hand cleaned. This is not definite but it is pretty certain.
Electronics Forum | Wed May 04 13:13:43 EDT 2005 | Jimmie
We have seen the black dot on the BGA pad after the component has been removed from a PCB. When most likely could this corrosion have occurred, while the component was in storage, during manufacturing of the unit? We have a number of these BGA's th
Electronics Forum | Thu May 05 17:15:46 EDT 2005 | russ
You got what I think someone has called a "cold melt". If you were to run your removal profile awhile longer you would not see this. Anyway, you don't have any issues as this is very common (at least in my experience). FYI I was thinking your oxid
Electronics Forum | Thu May 05 09:46:04 EDT 2005 | davef
Board fab, Defects, Pad coatings, Gold black plague articles 1 Nick Biunno's article: http://www.nukcg.org/downloadfiles/Hadco%20on%20Immersion%20Gold%20failures.pdf 2 George Milad's article: http://www.circuitree.com/ct/cda/articleinformation/featu
Electronics Forum | Fri Oct 29 10:02:28 EDT 1999 | John Thorup
Chris A lot of people have reported sudden, fab lot related problems with Ni/Au pads. These are usually characterized by a discoloration of the gold and called cheerful names like "black pad disease". This can be a process problem at your fab house
Electronics Forum | Thu Aug 21 22:10:07 EDT 2003 | adlsmt
Well, for some reason the board house will pay for the boards but has some issue with paying for the parts on them. Why am I not supprised? Perhaps I have mis-diagnosed the problem. We have found two different board p/n's with the same type of defec
