Electronics Forum | Tue Jan 24 11:59:55 EST 2006 | Chunks
Tell your board house/customers you want "non-smobc". hich stands for non-solder maske over bare copper. MPMs love exposed fids in just about any finish. You can always use pads on an MPM too.
Electronics Forum | Wed Mar 08 17:51:27 EST 2006 | pms
Chunks nailed it. You should not expect to see a perfect side fillet on this part, especially using no-clean, it's probably bare copper, hard to wick solder up the side of the lead.
Electronics Forum | Tue Mar 25 11:43:48 EDT 2014 | sara_pcb
It is Solder Mask on Bare copper, The land finish is HASL as per MIL-PRF-55110G which accepts trace of HASL as acceptable. Wetting is acceptable. regards, R.Saravanan
Electronics Forum | Tue Aug 02 12:19:48 EDT 2016 | proceng1
Actually I considered that, but I was thinking to leave the fiducial pad bare copper. These are customer supplied boards, but hopefully they will be willing to make the change for the next spin. Any tricks for getting it to see the boards we alre
Electronics Forum | Thu Dec 14 19:38:28 EST 2000 | Dave F
OK, now let me ask the really dopey question ... so if the irregularity of the HASL surface is punching holes in the thermal gasket and causing shorts to the heat sink, why are you putting solder on that surface? I wonder how the thermal conductivit
Electronics Forum | Thu Mar 16 12:48:12 EST 2006 | russ
The copper based part is it copper that you are soldering to or did you tell us what the base material was for the lead. Generally all leads are plated with something such as Tin/Lead, palladium over nickel, tin, etc... You cannot solder to bare co
Electronics Forum | Thu Jul 29 23:21:51 EDT 1999 | CH Lee
I received a request from customer to assemble ceramic substrate (alumina oxide)that printed with a low temperature Copper thick film conductor (the overglaze layer is polymer). The Copper pads are exposed without any coating. This ceramic substrate
Electronics Forum | Thu Sep 03 14:21:29 EDT 2009 | davef
Creeping corrosion occurs on bare metal. Most commonly, it is seen on boards with thin protective coatings [eg, bare copper, immersion silver, organic solderability preservative]. Look here: * enthone.com/docs/AlphaSTARCreeping.pdf * circuitree.com
Electronics Forum | Fri Dec 08 13:01:35 EST 2006 | Cmiller
I cant seem to get to that link but we tried everything we could think of and there was no way we found to get solder to adhere to the pads. I guess if you took a burnishing brush and polished the nickel off and got down to the bare copper you may be
Electronics Forum | Fri Jul 10 13:55:16 EDT 1998 | Bob Willis
After reflow the paste on a copper pad should spread out from its original print dimensions it should ideally not prior to reflow as that is a hot slump. The better the solderability of the OSP or the higher the activity of the flux will greter flow
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