Electronics Forum | Thu Nov 10 12:29:57 EST 2022 | stephendo
The G in ENIG is gold. It does not oxidise. Either you are thinking of OSP or your board shop is providing defective boards if your boards show oxidation. It would be the nickel that is oxidising but should be totally covered by the gold. Is there
Electronics Forum | Mon Jan 25 13:39:51 EST 2021 | grahamcooper22
Thanks for your reply. According to the manufacturer there isn't any palladium under the solderable coating on the chips...just nickel....i guess maybe the nickel is heavily oxidised. I have experienced the poor solubility (zero solubility at 210 deg
Electronics Forum | Fri Mar 07 21:10:31 EST 2003 | neil
Remember the gold is only deposited to provide an air barrier so that the nickel does not oxidise. Normally the gold is absorbed into the solder joint so that the solder forms a joint with the nickle. It is not unusual to see gold remaining on pads i
Electronics Forum | Fri Mar 01 03:16:01 EST 2013 | grahamcooper22
Solder paste flux formulation can make a difference when soldering to nickel silver...due to the alloy containing metals that oxidise easily like zinc and nickel then the flux has to be able to cope with the surface oxidation when the parts are in th
Electronics Forum | Mon Jun 17 13:45:29 EDT 2002 | genny
When the pad comes off, is it leaving behind a "black" area? Your board may be suffering from black pad - a condition that occasionally affects ENIG finish boards. It is a process control issue with your board fabricator. The nickel is oxidising b
Electronics Forum | Tue Apr 17 10:17:10 EDT 2001 | genny
Hi, ENIG finish is the same reason I came to this forum for the first time a few months ago. I found a bunch of useful information by searching the archives. Check it out. ENIG has some good properties like flatness, and the process control has i
Electronics Forum | Thu Mar 06 11:48:09 EST 2008 | muse95
Black pad with IAg??? Tarnish is NOT black pad. Tarnish is usually just some silver sulfide on the surface and can also usually be soldered through, by using a little additional, or slightly more agressive, flux, and still make a good quality solder
Electronics Forum | Fri Oct 01 04:03:31 EDT 1999 | Brian
| I am having problems processing immersion gold boards. The achieved solder joints appear acceptable a la IPC-A-610, but the resultant joint does not fully cover the land, i.e. you can still see an outline of gold pad. | What is the best way to achi
Electronics Forum | Thu Dec 15 02:09:22 EST 2005 | tk380514
SNAGGLETOOTH HOLDS HIS HANDS UP, HAVING JUST REACHED THE EDGE OF HIS OWN IGNORNACE. I just read up on black pads - http://www.emsnow.com/npps/story.cfm?ID=9784 when i checked the joints under the microscope they were a light grey slightly discolou
Electronics Forum | Mon Sep 13 06:23:06 EDT 1999 | Earl Moon
| | We have a product, with various PWBs, with over 600 parts each one (We are a low Volume/high mix company with an average component placement per PCB between 250 to 300 parts). This PWBs have 7 to 10, 20 mils pitch parts. We are having problems wi
