Electronics Forum | Fri Jul 23 06:48:23 EDT 2004 | mattkehoe
I am actually getting opinions that point to contaminated copper under the HASL finish. We've seen some "fish eyes" where the HASL is pulled away from the copper exposing a pin hole of copper that can be seen through the HASL finsh. We are planning o
Electronics Forum | Wed Jul 31 09:20:47 EDT 2002 | larryk
Dave, I'm assuming your unsoldered fids are exposed copper. Do you have any issues with machine vision due to the various color changes the copper goes through as it oxidies? Larry
Electronics Forum | Thu Jan 10 11:22:48 EST 2013 | pbarton
Looks to me like under etching of the underlying copper and the gold is just plated to all of the exposed copper surface. Is this characteristic the same on all solderable pads? You will not be able to remove this gold.
Electronics Forum | Thu Oct 14 16:38:29 EDT 2021 | SMTA-64387687
OSP is there to keep the copper from oxidizing. Once you wash the board, the copper is exposed. So, you have to either use it right away, or store it in a non-oxygen environment (vacuum/nitrogen).
Electronics Forum | Tue Jun 05 21:14:10 EDT 2001 | davef
You aren't going to post our stuff on your "Hey, I'm the wizard site", are you? Board fab, Pad coatings, OSP 1 OSPs: Imidazole (Via Systems) is good. Entek (Enthone) works, but requires strict thickness control in fab. 2 Enthone CU56 allows one t
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 | Thu Dec 13 20:54:23 EST 2001 | davef
There is neither �nominal thickness� nor �is there a set maximum� for via masking. We use some of our vias as test pads. So, as you�d expect, we get rabid when we get mask bleed onto these pads. IPC-6012 - Qualification & Performance For Rigid Pri
Electronics Forum | Wed Nov 17 10:03:29 EST 2010 | scottp
Instead of a minimum thickness, we require no exposed copper or SnCu intermetallic. We've been having a lot of trouble lately with suppliers of SN100 HASL boards giving us pads with very irregular solder deposits with areas of exposed intermetallic.
Electronics Forum | Thu Apr 14 15:27:05 EDT 2022 | ppcbs
If it was ROHS I would suspect copper migration. In my experience an acceptable copper finish should last up to at least 6 reflow cycles. If you have bubbles or blow holes in the solder joint, that is a sign of voids in the walls of the copper barre
Electronics Forum | Tue Dec 14 12:00:34 EST 1999 | Kris Wiederhold
We recently reduced our standard aperture reduction to aid in the reduction of solder on gold defects. Since this reduction in aperture size, we have been experiencing exposed copper at the end of the component pads. The heel and toe joints are per