Electronics Forum | Fri Nov 08 08:52:54 EST 2002 | dphilbrick
Juan There are many things that cause this and the first thing I would do is request quality records from your board fab facility on that particular lot. If they are unwilling to give them to you this is a good sign they had a processing problem. Th
Electronics Forum | Thu Sep 30 16:28:51 EDT 2010 | 18424
Hello All, looking for some help from you guru's. I have several Enig boards with solderability problems. Components ranging from 0402's to ssop's. Using AIM W/S leaded solder paste, profile is beautiful and has been for years running the same produc
Electronics Forum | Thu Aug 01 08:58:47 EDT 2002 | Rick Lathrop
Good morning Dave F. I am not going to try to touchup the solder pad until I get surface analysis work done, don't want to ruin the evidence. I am getting XPS work done not XRF, XPS is X-ray Photoelectron Spectroscopy and can see very thin films of o
Electronics Forum | Thu Aug 29 07:46:39 EDT 2002 | nifhail
Hello Experts We ran into problem today when one of the board that we assembled having problem at Test, BGA failure. The joints looks good but no continuity. When trying to remove the BGA, i found that the pad on the PCB is intact but black in colou
Electronics Forum | Mon Jan 03 16:34:10 EST 2005 | davef
The main advantage if ENIG over HASL is that ENIG is flat and HASL generally is not. The main disadvanages to ENIG over HASL are: * Cost of ENIG is 1.5 - 2X higher than HASL * Selflife is less than HASL * You solder to nickel, rather than copper * E
Electronics Forum | Sat Mar 15 09:30:29 EDT 2008 | davef
Unlike other solderability protection, immersion coatings [eg, ImAg, ImSn, OSP, etc] can be reworked by the board fabricator prior to assembly operations. Reasons for selecting immersion are: * Until a supplier can demonstrate that they can turn bla
Electronics Forum | Wed Jan 21 04:14:19 EST 2009 | sachu_70
Hi Adam, I would suggest you refer IPC-2221 guidelines which define plating thickness as: Nickel 2.5-5.0 um , Gold 0.08-0.23 um. Although ENIG is a standard process, there is an associated risk towards Gold embrittlement, Porous Gold, or Black pad de
Electronics Forum | Fri Nov 08 17:49:05 EST 2013 | davef
First, it's a surprise that your failure analysis lab thought everything was OK with these boards. They look like shit. Second, a few years ago, there was a bunch of complaints about ENIG boards with issues similar to what you're observing. There wa
Electronics Forum | Wed Aug 12 22:18:42 EDT 2020 | stephendo
Almost all the people here buy boards with the metal already plated on. We are mostly assembly people. The ones you really want to talk to are PCB fab people. And if you want to look into plating PCBs, I would suggest you look up Black Pad. It hasn'
Electronics Forum | Mon May 20 21:29:52 EDT 2002 | davef
Q1: Are we saying then that IMC can occur at the solder / Cu pad join on the PCB when finished assembled? A1: Yes, but in a broader context I am saying that when someone solders correctly, they form an IMC. Q2: Will the tin diffuse with the Cu over