Electronics Forum | Wed Sep 03 11:47:08 EDT 2008 | realchunks
That sounds like a "Coupla microns thick" Dave.
Electronics Forum | Tue Sep 02 13:26:52 EDT 2008 | vladig
You should have a few microns of Sn on a board. Vlad
Electronics Forum | Wed Sep 03 12:35:47 EDT 2008 | realchunks
I believe Vlad is a sales person for Sentec.
Electronics Forum | Tue Sep 02 09:32:45 EDT 2008 | eliezerk
In order to check pcb quality by HASL TIN thickness plating repeatability, looking for any specification for the above.
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 | Tue Sep 02 22:21:26 EDT 2008 | davef
IPC-6012 Table 3-2. States "Fused tin-lead or solder coat - Coverage and Solderable". The lack of any specific dimension criteria doesn't make this any less a requirement. There must be complete coverage of solder on the land, and it must be wettable
Electronics Forum | Wed Sep 03 07:36:39 EDT 2008 | vladig
That is why it has to be a few micron thick. Otherwise, it will form a layer of intermetallic which is extrremely difficult to solder to. Vlad
Electronics Forum | Wed Sep 03 11:52:58 EDT 2008 | stepheniii
But Vlad was talking tin and Davef gave intermetalic thicknesses which Vlad said needs to be avoided by having a few microns of tin. I'm not 100% sure but I suspect that DaveF is not convinced that Vlad knows what "intermetalic" means.
Electronics Forum | Wed Sep 03 09:27:19 EDT 2008 | stepheniii
Do you mean "at least a few microns" or "no more than a few microns"?
Electronics Forum | Thu Sep 04 11:06:44 EDT 2008 | realchunks
Not sure why you would... but here are a couple of links that may help if you are having manufacturing problems http://www.smtinfo.net/docs/Electronic%20Production/9.htm http://www.midwestpcb.com/capabilities/plating2.html Granted I only have a Ma
