Electronics Forum | Mon Aug 14 14:53:51 EDT 2017 | emeto
AIM, Indium , Alpha will be your top 3 choices. I did paste evaluation before with 4 paste manufacturers and Kester was my choice number 4. Profile according to the paste specs and observe results.
Electronics Forum | Thu Aug 10 07:29:43 EDT 2017 | stivais
How do you evaluate the soldering quality for those QFNs? X-Ray or AOI? For some QFNs (and other bottom termination components) it's not supposed to have solder fillets on toes. It's also noted in IPC-A-610 (Rev.F 8.3.13). Take a look at your QFN ch
Electronics Forum | Thu Aug 10 11:24:18 EDT 2017 | dleeper
The exposed metallization on the sides of the QFN probably aren't tinned and therefore not expected to have solder wetted to them. If previous parts formed nice toe filets, it might just be that those parts were fresher and the exposed metal did not
Electronics Forum | Wed Aug 09 20:03:22 EDT 2017 | ttheis
We're having problems with Kester pastes (NP545 pb free and EP265 60/40 no clean pastes.) All of our other components reflow just fine with either paste, but for some reason this QFN chip doesn't wick to the QFN's pads well. It seems like some type
Electronics Forum | Thu Aug 10 10:52:11 EDT 2017 | ttheis
We are just using a stereo microscope at this time. When we first started out with these parts a year ago they filleted very well but with no apparent change they began having problems. While the boards do work, we are concerned about the long term r
Electronics Forum | Sun Sep 12 12:45:56 EDT 2010 | tony1
Hi there, does anyone experience in NiPdAu solderability dip & look test? I experiencing solder non wet issue on side I/O & also center ground for QFN package. Appreciate someone can offer me a solution. Thanks
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 | Thu Jul 05 15:13:46 EDT 2007 | joeherz
We've seen non-functional QFNs cured by touching up the toe fillets. Especially with parts that are not plated on the edge/face where you get minimal/no wetting due to oxidation of bare copper. I'm not suggesting that you touch everything up but th
Electronics Forum | Thu Jun 23 17:59:02 EDT 2005 | davef
Jason: We'd like to help, but we don't know how to diagnose "bad solder quality". It's too broad of a complaint. Please be more descriptive, like: * Too much solder * Too little solder * Solder has too sharp of wetting angle
Electronics Forum | Fri Nov 09 10:46:24 EST 2007 | hussman
What is the real problem? No-solder can mean a variety of things. No-solder due to lack of paste? No wetting to the part? Co-planer part? Please specify......
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