Electronics Forum | Fri Oct 30 10:36:26 EDT 2009 | richie_puthotta
Hi, I see a huge solder mask shift on chip comp pads. This would result in mid-chip solder balls or solder beads. Overall, the solder mask workmanship is not acceptable. Mask is on pad.
Electronics Forum | Wed Mar 17 19:41:15 EST 2004 | Dreamsniper
I'm hit with the above problem and found out that the BGA's themselves have fibres on their solder balls. I have soldered some without having the knowledge of the above fibres and found that the fibres are caught between the PCB pad and the BGA solde
Electronics Forum | Thu Jul 29 15:00:22 EDT 2004 | Sam Haq
Hi, I am trying to locate a vendor for very low alpha count solder balls. Solder is 63Sn/37Pb or 62Sn/36Pb/2Ag. Ball Specifications 63% tin / 37% lead solder (optional 2% silver in the form of 62/36/2 would be acceptable) 300 micron diameter
Electronics Forum | Thu Oct 26 17:42:29 EDT 2000 | Philip A. Reyes
Hi Mr Paul! Thanks for answering my previous questions. Hope you can still accommodate my other queries. This is about the acceptable criteria of PBGA defects after reflow soldering. 1.What is the allowable (min and max. ball misregistration / misal
Electronics Forum | Mon Oct 21 03:52:38 EDT 2002 | Ben
I'm doing lead-free SMT of BGA with 450 micron ball. I found there are lots of voids under xray, there are around 2-3 voids in every balls. It is around 10% of volume ratio. I would like to ask if anyone know there is any standard of acceptable maxim
Electronics Forum | Tue Mar 09 17:52:05 EST 2004 | davef
Bryan: Comments are: * You're correct, solder paste formualtion is a major driver to voiding in BGA balls. * Voids are primarily process indicators. There is experimental evidence that voids retard crack propagation locally around the void on a temp
Electronics Forum | Wed Mar 14 16:30:02 EST 2001 | CAL
Reading x-rays is an art. All balls should be symmetrical in size and shape. Please provide more information on your question. Why just opens? If the Balls are not consistently the same in size or shape there is a problem. Larger balls could be from
Electronics Forum | Tue Feb 12 18:48:48 EST 2008 | larryd
Thanks for the spare change. Questions are good and I did miss one item. Process has 100% solder paste inspection with a 3D inspection machine that has very few false calls or accepts. Ramp to peak is less than 1.5C/sec. Profile looks good, solder
Electronics Forum | Tue Jan 16 14:53:24 EST 2001 | davef
Yanno what's interesting on that topic? A small number of voids make the solder connection of a BGA stronger than no voids. Moral of the story ... don't get too anal about voids. You should check the archives ;-) [har har har] we've discussed this
Electronics Forum | Tue Apr 27 05:10:34 EDT 1999 | Earl Moon
| Which is the preferred method for soldering a bga, adding solder paste or not? Solderpaste manufacturers say to add solder while the rework station manufacturer's say it's not necessary. | Paste is preferred by not necessary. Our studies, conduct
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