All, We currently apply ENIG prior to soldermask, or should I say our subcontractor recommended that we allow them to do so to prevent "black pad". I was told that the reason being was because they recieve such a wide variety of different soldermasks from so many different board shops that their could be sross contamination. The boards we build are very expensive so we yielded their advice and have not had a solderability problem with a customer since. Sometimes trying to save a buck is not worth the effort. I would rather have a satisfied customer than a few extra dollars saved, especially this day and age. Tony Steinke AIT-Atlanta Inc. ----- Original Message ----- From: Damon DeSilva To: [log in to unmask] Sent: Monday, July 22, 2002 11:47 AM Subject: Re: [TN] Au-Ni coating I suppose you could Au plate your entire panel prior to solder mask, if you like giving away $. Solder mask is applied prior too not as a post process. -----Original Message----- From: TechNet [mailto:[log in to unmask]]On Behalf Of [log in to unmask] Sent: Monday, July 22, 2002 1:56 PM To: [log in to unmask]; [log in to unmask] Subject: Re: [TN] Au-Ni coating Sorry, but in most cases the immersion gold process follows soldermask. We have a link to an article about black pad at http://www.protoengineering.com/immersion_gold.htm At 08:39 AM 7/22/02, you wrote: Bruce: My understanding of Black Pad was it is caused by too much phosphorus in the nickel (as I recall) plating bath. Solder mask contamination is a new one for me. With mask going on after the gold, how does it contaminate the nickel? Mask should not come in contact with the nickel at all in my experience I am interested in learning all nuances of black pad causation. Would appreciate your comments. Charlie McMahon Misner, Bruce wrote: Congratulations. Sounds like you are the proud owner of Black Pad Disease or better known as Black-line Nickel (BLN), an unpredictable low-level defect of ENIG. It has been traced to electroless nickel plating bath contamination by uncured soldermask, although I'm not convinced this is the only cause. Good Luck, Bruce Misner ---------- From: Marki Sasportas[SMTP:[log in to unmask]] Reply To: TechNet E-Mail Forum.;Marki Sasportas Sent: Monday, July 22, 2002 8:03 AM To: [log in to unmask] Subject: [TN] Au-Ni coating Hello All, I have problem in BGA rework, In some cases after, heating specific zone on the board ( gold finish) A near BGA joints are being defected. After taking off this BGA I noticed that some of the pads are black, What can cause the problem? Thanks in advance, Sasportas Marki, CreoScitex Corporation Ltd. -------------------------------------------------------------------------- ------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8e To unsubscribe, send a message to ------- --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------