Electronics Forum | Thu Oct 24 14:10:53 EDT 2002 | Terry Burnette
I've been informed that I can't post the Dye Penetrant paper on the SMTNET library till Advanced Packaging releases the paper in their Dec. issue. You should be able to pull a copy in the next couple of weeks from their site, http://ap.pennnet.com/ho
Electronics Forum | Thu Nov 07 10:59:11 EST 2002 | pjc
IPC-7525 "Stencil Design Guidelines" is a good reference document to have. Here are notes from a Tessera, (a major mBGA mfg.), study- "Application Note Solder Stencil Requirement for mBGA" The stencil aperture is to be square, equal in size to the l
Electronics Forum | Wed Aug 27 14:41:49 EDT 2003 | Stephen
Have you checked the temperature profile at the balls? Just because a recipe works "fine most of the time" does not mean it is optimum. Do you have a machine that can measure co-planarity? If I get time I plan on using the MPA to look at co-plana
Electronics Forum | Wed Apr 21 11:33:20 EDT 2004 | tigerlordgm
As one of our small batch processes, we place BGAs on PCB without using solder paste. We apply tacky flux to a predetermined height on a pallet, "dip" the BGA into the tacky flux to wet the solder balls to the set height, and then use a BGA rework st
Electronics Forum | Mon Apr 26 09:11:04 EDT 2004 | Daniel
Thanks, We currently use Metcals for our regular work and I was looking at the ERSA system for the BGA rework. From what I have seen it seems simple to use, and since it uses IR you don�t need all the attachments for different size BGA�s. You just
Electronics Forum | Sat Sep 18 12:10:19 EDT 2004 | Steve Gregory
I have a question about solder masking via's in a BGA pattern, and want to see if I'm thinking correctly about this. This problem is kind of along the same line as Carol's problem earlier. I think it's a bad idea to leave the via's free from solder
Electronics Forum | Tue Dec 06 15:27:36 EST 2005 | Mike
Steve, You are correct in that X-Ray image of a BGA will not show flux residue. So what? If you are using no clean flux then I would think it doesn't matter if there is some flux residue. Sure if you are reworking a BGA and the operator dumps t
Electronics Forum | Wed Jun 21 11:09:37 EDT 2006 | samir
Muse, I agree. There has been much debate but the previous scenarios discussed in the forum have been regarding the SAC/RoHS BGA and Sn-Pb paste. I have successfully collapsed a SAC BGA with a Sn-Pb paste using the "hybrid" profile that Amol refers
Electronics Forum | Sun Jan 14 16:35:48 EST 2007 | Austin
I have several boards built at various CM's. We have prototype builds with some JTAG failures on BGA's (1-3 failures with qty 3, 1500 pin BGA's). CM's always claim reflow profiles look good. X-ray does not show bridges and they claim it looks good, b
Electronics Forum | Fri Apr 13 10:13:30 EDT 2007 | Bob R.
We had a crisis with one BGA causing huge yield losses due to this defect. Nothing we could do with the profile got rid of it. Changing paste didn't get rid of it. It was the BGA warping in reflow, caused the corners to lift up when the solder was
