Electronics Forum | Thu May 26 07:50:33 EDT 2011 | scottp
What process steps have been completed before the cross-section? What type of devices have solder cracks? Are the cracks found after just normal processing or after some type of validation testing? It is very unlikely to be a heating/cooling issue
Electronics Forum | Wed May 25 21:03:30 EDT 2011 | thanhnguyen22
Hi All, I am new the PCBA process fabrication. I have found many cracks in the PCB after we have cross sections analysis. The cracking has same kind of pattern. It happens betwen the solder and the PCB, or between the solder and the part, BUT not be
Electronics Forum | Mon Mar 24 12:11:11 EDT 2008 | jdumont
Thats the one I found while researching this AM also. Thanks for the assist. Any ideas if this can be process related? Im sure it can be but its odd that it only happens on one vendors board. I think because it is an 10 layer board that maybe they ha
Electronics Forum | Mon Mar 24 22:53:22 EDT 2008 | davef
As you say, just about defect can be tied to process, one way or another. If you want to think about it, search the fine SMTnet Archives for background on barrel cracking. Other things are: * How thick is the actual via plating from the two supplier
Electronics Forum | Thu Feb 19 12:45:05 EST 1998 | Earl Moon
| I have an Electrovert Ultrapak 445 Wavesolder machine with 3 IR preheat zones and a single wave with omega wave. | I want to run a DOE (Taguchi) to determine the optimum settings for soldering both single-sided and | double-sided boards. Can any
Electronics Forum | Tue Aug 21 21:39:19 EDT 2001 | davef
1) why is No-clean (NC) the preferred process, for BGA mounting by SMT? Probably the same reason NC is the preferred process for mounting non-area array SMT components. 2) why is water-soluble (WS) not a hot choice? There�s not reason not to use
Electronics Forum | Mon Dec 02 16:25:06 EST 2002 | jimlew
In doing process qualifications for 0201 caps, has anyone taken cross-sections and discovered cracks / hairline fractures / voids between the metalization on the end and the ceramic itself? (not cracks in the solder joint) We are well within the cap
Electronics Forum | Mon Apr 27 19:31:12 EDT 2009 | stevek
Remember that the 25% is a reduction in cross sectional area. A void in the middle of the ball that reduces the cross sectional area by 25% is about half the diameter of the ball. If it is closer to either termination, the corresponding size would
Electronics Forum | Thu Jul 05 13:47:10 EDT 2007 | arun2382
QFN assembled on a PCB indicates paramteric fails when tested. When the QFN on PCB is reflowed a second time, it recovers and passes testing. Visual, X-ray inspection revealed no anomalies. Cross-section images of solder joint revealed no anomalies (
Electronics Forum | Tue Aug 05 01:13:22 EDT 2008 | Sean
Dear all, As far as I know hot tear or shrink hole defect only happen at plated though hole soldering, especially for those lead free wave process. Recently, a laboratory engineer had done cross section on some of the SMT BGA ball and IC lead solde
