Electronics Forum | Fri Feb 22 15:16:24 EST 2002 | rkevin
Bet your using tin/ lead plated components with a lead free Cu/Ag/Sn alloy. It leads to intermetallic cracking. Wow didn't anyone tell you to check the archives yet, It seems to be the answer given to everyone. Why have an interactive site if you alw
Electronics Forum | Wed Feb 20 23:17:34 EST 2002 | surachai
I AM JUST EVALUATION LEAD FREE EVALUATION AND FOUND THE BIG PROBLEM OF SOLDER CRACK BETWEEN TERMINAL OF COMPONENT AND THE INTERMETALLIC LAYER OF LEAD FREE ALLOY BUT DON'T FIND ANY CRACK BETWEEN SOLDER AND SURFACE OF PCB , COULD YOU HELP ME VERIFY T
Electronics Forum | Tue Apr 13 08:21:05 EDT 2010 | esca
Hi manchella, After ATC test, two different failure modes can be present: solder FATIGUE (into bulk) or BRITTLE INTERMETALLIC fracture. So, first you have to verify this. Moreover, which brand of SMT paste have you used ? The crack into solder joint
Electronics Forum | Fri Oct 10 13:35:56 EDT 2003 | swagner
Does anyone have any data about the dangers of reflowing BGA's twice? I have a customer that is concearned about cracking in the intermetallic layer after the second pass. Thanks in advance.
Electronics Forum | Tue Jun 13 13:42:34 EDT 2006 | Bob R.
Also be careful in assuming you have black pad. A nice straight crack along the Sn-Ni intermetallic is probably just overstress at some process (most likely ICT). The better board suppliers figured out how to avoid black pad years ago.
Electronics Forum | Tue Nov 10 07:35:04 EST 2009 | scottp
Step 1 is to find out what kind of opens you're getting through a cross-section or die & pry. Are they head in pillow, brittle fracture at the intermetallic, bulk solder cracks, ball separation from interposer? Without some basic failure analysis a
Electronics Forum | Thu Sep 07 08:50:45 EDT 2006 | Grant
Hi, We have seen a slight rise in failures in a product, and on investigation, the BGA ball has cracked off the PCB. It's below the intermetalic layer in the ball. Reflow otherwise looks good, and the raw components are clean. I am wondering what c
Electronics Forum | Tue Jan 10 11:51:16 EST 2006 | jax
I don't believe I have ever seen a non-destructive test for "Black Pad" that I could take back to a Fab house and collect monetary losses with... But if this test method actually does hold merit then collect away. I would like to know how this metho
Electronics Forum | Mon Oct 04 07:48:34 EDT 2010 | scottp
When you break them where is the failure? Is it the solder joint (doubtful), the part termination, the body of the part, or the board? If in the solder joint, is it in the bulk solder or intermetallic? If in the part, what direction is the crack?
Electronics Forum | Fri Sep 17 03:55:45 EDT 1999 | Brian
| We have some SMT components with gold plated leads. They're actually LCC led packages. A good solder alloy to use would be Indium / Lead to reduce tin dissolution into the gold and avoid the resultant brittle intermetallic compound. However, a reco
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