Electronics Forum | Wed Jul 07 09:47:41 EDT 1999 | Peter Brant
| | Q #1) Is it more reliable to have the mask tent over the vias or risk getting vias half filled with solder? These are vias with an .020" hole and .040" or .050" pad. WIth regards to this question, and scott's follow up, I have used the "epoxy me
Electronics Forum | Wed Feb 01 18:11:43 EST 2006 | Chris
I wonder if they are concerned about getting chemicals trapped in the tented vias. If the tented vias have pin hole openings or even larger openings, chemicals from the ENIG process could become entrapped in the via holes and not washed away in the
Electronics Forum | Wed Jan 06 09:38:59 EST 2010 | lynn_norman
Via failure could be caused by cracks in the barrel, or thin plating, or fractures in the traces leading to the vias, . X-ray analysis could pick up a fractured trace and cross-sectioning of the vias could pick up the cracks and thin plating. Secon
Electronics Forum | Fri Sep 04 07:26:23 EDT 2009 | Sean
Dear Davef, Thanks for sharing with me..I observed this creeping corrosion tend to appear on PCB via hole rather than other PCB location. Why this problem did not appear on PCB traces? Besides, I also notice that this problem only appear on the PC
Electronics Forum | Tue Jan 20 11:54:12 EST 2009 | smt_guy
Is this Corrosion? We found our boards with this issue 45 days after they were delivered to us from supplier. The board finish is HAL Leaded. But I noticed that the corrosion like issues are coming form the tiny via holes with SILVER EPOXY FILLING.
Electronics Forum | Thu Sep 17 23:36:35 EDT 2009 | Sean
All, We know that incomplete immersion silver could potentially lead this creeping corrosion. Is there any way to check bare PCB for incomplete immersion silver coverage, especially on the via hole area? Thanks, Sean.
Electronics Forum | Tue Feb 23 08:46:11 EST 2021 | dianau
Hello, I have a topic with vias discoloration(that's what supplier said) and I don't know if it's an corrosion problem or something else. I believe that maybe the PCB's are not storage properly. I must mention that aren't any problem at soldering. D
Electronics Forum | Tue Oct 07 12:35:10 EDT 2008 | andy_pal
Hi All, I am using COB on my DOUBLE SIDED PCB. lastly we used Eletrolytic Ni / Flash Gold Plating. Our Boards vias Failed the UL corrosion Test. we did some cross-section analysis and found 10.75 �m of Nickel and 0.022 um of Gold and as the Process
Electronics Forum | Tue Jan 20 17:00:05 EST 2009 | davef
For lack of a better description, we'd say, "Yes, that could be corrosion." Regardless of what you call it, it looks nasty and should not be allowed on bare boards of any sort. Based on your picture, we can't tell you whether it's related to your con
Electronics Forum | Wed Jan 21 13:48:16 EST 2009 | smt_guy
hi davef, good idea! run one sample and see waht happens with the solderability. yeah we received them good and just happened after 45 days in our stock room. I suspect that during the HAL process some parts of the vias with epoxy fillings were no
