Electronics Forum | Wed Aug 11 18:36:03 EDT 2004 | davef
90 Knoop. Q2: Thickness is 4 to 10 u" for Au and 300 to 400 u" for nickel A2: This looks like a ENIG spec. Although, the Ni is quite heavy, 150 uin is sufficient for most applications. [IPC-4552 ENIG specification: * Gold thickness of 0.075 - 0.125
Electronics Forum | Fri Oct 29 10:02:28 EDT 1999 | John Thorup
Chris A lot of people have reported sudden, fab lot related problems with Ni/Au pads. These are usually characterized by a discoloration of the gold and called cheerful names like "black pad disease". This can be a process problem at your fab house
Electronics Forum | Tue May 19 12:54:55 EDT 1998 | Richard Jackson
| We had a similar problem. But whenever the solder came from the screen printer the solder would wet to the gold fingers, with the help of residual flux. But the problem is balls, that I assume are not wetted to the gold fingers but instead are jus
Electronics Forum | Mon Jul 03 23:11:04 EDT 2000 | Patrick Ng
hi, We are receiving PCBs with gold fingers "discolored". The "discolored" gold fingers can be removed if rub with soft eraser! We are working with suppliers to determine the root cause and eliminate this issue. Pls assist if you have encountered si
Electronics Forum | Thu Jul 06 20:10:06 EDT 2000 | Dave F
I agree. Make them quit doing this ugly thing to your boards!!!
Electronics Forum | Mon Oct 20 14:17:35 EDT 2008 | robinj
The discoloration/shadow appearance is a clear sign of black pad which is from nickel corrosion in the gold bath.
Electronics Forum | Tue Oct 26 12:18:53 EDT 1999 | Gary Kemp
We are having a discolorization problem with the gold fingers on our PCB's. I have been made aware that there is a gold touch-up paint (masking) that is available. Would anyone know where I can get my hands on some of it? Any help would be appreci
Electronics Forum | Fri Sep 12 17:58:30 EDT 2008 | robinj
Can someone let me know what is causing this black coloration around the pads? It is on the edge of all pads all over the board. The surface finish is OSP. I don't have any solderability issue. But the stencil printer is having trouble with picking u
Electronics Forum | Sat Sep 13 09:36:53 EDT 2008 | davef
Lemme tell ya, those are weird looking pix. If OSP boards have not been dried properly prior to bagging and sealing, water can leak from via and ruin the OSP, which will turn black.
Electronics Forum | Tue Oct 26 14:11:25 EDT 1999 | Dave F
Gary: Two things: 1 Reworking golding fingers is an old topic, check the SMTnet archives to get started. 2 Gold fingers should not be discoloring, unless: * You are doing something bad to them ... OR * Your supplier has doinked the process, which
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