Electronics Forum | Thu Feb 21 13:08:06 EST 2002 | vincent_f
Hello, I had recently a problem of crack between the solder ball (SnPb) and the Ni layer of the PCB pad. We use Electroless Ni/Au technology for PCB. This phenomena is amazing because the crack is very clean (straight) and it creates a space betwee
Electronics Forum | Thu Apr 22 07:51:32 EDT 1999 | Vic Lau
after soldering transistors on a flex circuit (Ni/Au plated), one of the lead lift-up from the pad. under microscope (1,000 X), i find some cracks on the the pad surface. with edx analysis, the surface is mainly nickel. have you ever encounter suc
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 Oct 26 08:41:56 EDT 2004 | Bob R.
When we first got into BGAs on ENIG we were getting joint cracking at in-circuit test. The joints were breaking in the Sn-Ni intermetallic. We did a lot of pull testing while working with our board suppliers and our conclusion was that pull testing
Electronics Forum | Thu Apr 18 16:52:15 EDT 2002 | davef
General comments are: * First place I would look is the supplier of the pins that you are trying to install. Most suppliers that sell press fit components have done a good deal of work to qualify the component and will have all the specifications yo
Electronics Forum | Mon Apr 29 05:25:13 EDT 2002 | ianchan
Hi, we do Sn plated I/O pinning insertion into Ni/Au thru' holes. no problems here so far, as we cater for the "interference" (fit-allowances) of the I/O pin into the thru' diameter, via improved PCB thru' hole designs. before this cater/considerati
Electronics Forum | Wed Feb 02 20:53:34 EST 2000 | Dave F
Dennis: Several points: 1 If you're talking AlphaLevel process (?): � Good solderability, as HASL, even no-cleans bite well. � Planarity, uniform deposit, no bridgin� of FP. � Doesn't store as well as NiAu ... LT 6 months sealed � Very sensitive t
Electronics Forum | Wed Aug 26 05:24:42 EDT 2009 | ghepo
Ok Eric, finally we know that the problem should be the PILLOW (sincerely, your photo is not very clear) and not the crack of the joint. There is a big difference on the failure mode of the two defects... If the problem is realy a pillow I only ca
Electronics Forum | Wed Jan 17 20:48:14 EST 2001 | davef
We find that the raw BGA's pad sheared surface has the SnPb solder at various Z heights whereas the assembled BGAs pad leave a smooth layer of SnPb along the pad. Like to understand the cause for the difference. Who could guess? Solder joint streng
Electronics Forum | Wed Dec 09 10:02:10 EST 1998 | Earl Moon
| Does anybody out there have any special insights into utilizing no clean paste in high frequency RF applications? I would imagine there may be some issues with solder balls that would affect functional test (Earl, do you have something for me here?
| 1 |
winsouce.jpg)