Electronics Forum | Wed Nov 14 01:00:20 EST 2007 | reypal
recently, we also have problem with QFN around 3% defect related to soldering. from the cross section it turns out to be solder crack. it could be the paste volume on the center pad is too much causing QFN to float that eventually will cause crack on
Electronics Forum | Fri Feb 15 17:50:30 EST 2008 | stevek
Creating a sound tin nickel intermetalic takes a bit more energy than other finishes (such as copper or tin). You can achieve wetting, but not have a viable intermetalic. You should cross section some intact boards from that process and see what th
Electronics Forum | Tue Mar 04 03:24:43 EST 2008 | reypal
I need some advise from those with experience on this component. We are facing soldering problem "pillow effect"(from cross section result)on this BGA. In the reflow profile point of view which area should we focused more? The soak time or the Total
Electronics Forum | Thu Mar 06 14:34:16 EST 2008 | srmlan
I have not had problems with ENiG panels, but they were made state side. We had Trace Labs cross-section them and found no problems. Whats this about yellow nails? Mine are full of grease from constantly having to fix the Jeep. I would try to pop my
Electronics Forum | Thu Apr 24 21:52:18 EDT 2008 | fowlerchang
We have measured the temperature of CSP solder joint. The peak temperature is 232oC and the wetting time above 217oC is 30s. But we use leaded solder paste instead of lead free solder paste. I doubt why no crack of solder joint was observed after cr
Electronics Forum | Thu May 01 15:42:53 EDT 2008 | ck_the_flip
Yes, the authors do give the caveat that small amount of lead contamination in a SAC/Lead-Free system is tolerated provided the Pb-BGA has sufficiently reflowed. This verbiage is on the bottom of Figure 10. For my own peace-of-mind, I would send yo
Electronics Forum | Wed Aug 27 13:15:50 EDT 2008 | vladig
Well, it's difficult to play with the profile without knowing the root cause for the problem. A simple cross-section can tell you whether the component is at fault or not. If it doesn't point out to the root cause then and SEM/EDS analysis on one of
Electronics Forum | Tue Sep 09 19:35:26 EDT 2008 | vladig
OK. Here it goes. It's a series images taken after cross-sectionning one of the components. I hope that it's obvious now that teh "knob turning" technique wouldn't work that time around :-) I have one more image in my "back pocket", which explains
Electronics Forum | Wed Aug 27 09:30:22 EDT 2008 | vladig
Hi Eyal, Sure you can do that. You might be able to use your "typical" reflow profile for eutectic, or tweak it slightly. it's a good idea to do a trial run and then get a couple of components cross-sectioned and checked for the microstructure of th
Electronics Forum | Fri Feb 13 19:51:07 EST 2009 | joeherz
Update Received cross-section analysis for ENIG plated boards and am happy to report that we have no voiding issues. Intermetalics look great and no copper dissolution. No process parameters were changed, only the PCB plating. For now, we are onl