Electronics Forum | Mon Feb 19 17:34:02 EST 2007 | GS
Thank You Pavel and Dave, Unfortunately I do not have IPC-4554. Anyway I 0.6-1.0umm is what I remember, and confirmed by reading also through leterature available on google. I was just going to understand if it possible to obtain more thickness
Electronics Forum | Wed Sep 10 12:56:09 EDT 2003 | davef
Intermetallic compounds [IMC]: * Form during the alloying process of some metals. In soldering these are Sn, Ni, Ag, Cu, Au. * Do not accept solder. * Increase in depth in logarithmic proportion to both time and temperature. [So during the solder
Electronics Forum | Wed Sep 03 07:43:13 EDT 2008 | davef
What do you mean by a "few micron thick"? IMC thickness pre-cycling (NEMI Lead-free) * Cu3Sn: 3um [118 uin] * Cu6Sn5: 1um [40 uin]
Electronics Forum | Wed Sep 03 16:59:13 EDT 2008 | glennster
At a former employer we required HASL thicknes to be a minimum of 0.75 micron (30 microinches), as measured at the thinnest point on any given pad. This would generally assure a minimum 1 year solderability shelf life. Usually when we saw a soldera
Electronics Forum | Thu Sep 21 20:59:55 EDT 2017 | davef
There is no standard minimum / maximum IMC thickness. * There needs to be an IMC * Thinner IMCs are preferred over thicker IMCs
Electronics Forum | Tue Jul 14 07:23:50 EDT 2020 | researchmfg
There is a misunderstanding that people think the IMC layer grows the thicker the stronger soldering strength. The IMC layer can be grown and distributed evenly at the interface location will be good enough. Once the IMC layer grows too thick and ove
Electronics Forum | Mon Feb 21 21:28:13 EST 2005 | abhirami
Davef, We see increased IMC thickness for electroless Ni and the brittle mode failure occurs much earlier in multiple reflows, exposing IMC layers. Not good for board level reliability.Regards. GV
Electronics Forum | Tue Sep 24 18:38:54 EDT 2019 | researchmfg
Well, there may be a misunderstanding that people think the IMC layer grows the thicker the more strong soldering strength. Actually, the IMC layer can be grown and distributed evenly at the interface between Cu-based, Ni-based and Sn-solder will be
Electronics Forum | Wed Oct 10 16:16:15 EDT 2001 | lisa
Hello all, I'm looking for some advice on inter-metallic formation. I have some circuit board finished with Immersion Tin, Immersion Silver and OSP. They have been reflowed with solder past and components,the joints look good. What can I expect fo
Electronics Forum | Wed Oct 10 20:58:30 EDT 2001 | davef
Several points are: * There�s quite a bit of background on IMC in the fine SMTnet Archives. I�ll try not to duplicate it. * If you have a smooth and well-formed solder connection using fairly common materials, you assuredly will have IMC. Any evide
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