The danger with "thin"gold is that it may be porous and if it is, the Nickel underneath will oxidise and give rise to solderability issues. The flash gold process, though, is self-limiting in the thickness it achieves, so you may be OK. Just in case, don't store the boards too long before using them. I usually specify 4-5 microinches gold on my boards. Peter Dave Chapman <[log in to unmask]> 04/01/2003 01:51 AM Sent by: TechNet <[log in to unmask]> Please respond to "TechNet E-Mail Forum."; Please respond to Dave Chapman To: [log in to unmask] cc: (bcc: DUNCAN Peter/Asst Prin Engr/ST Aero/ST Group) Subject: Re: [TN] 'Thin' Immersion Gold Finish? If the gold is going to be used under a contact switch where there is going to be movement or wiping, the gold should be thicker. If the gold will just be for component attachment we have used the thinner "Flash" gold. Dave Chapman Mfg. Engineer Circuit Service Inc. -----Original Message----- From: Rick Thompson [mailto:[log in to unmask]] Sent: Friday, January 03, 2003 11:29 AM To: [log in to unmask] Subject: [TN] 'Thin' Immersion Gold Finish? We have an overseas board supplier that is supplying an immersion gold finished board that is only 1-1.5 microinches of gold over 100 microinches of nickel. I believe this may be too thin a gold layer for adequate protection of the nickel but don't have any objective evidence for this. Can anybody give me any feedback or other information sources that might support this? IPC-2221 specifies approximately 3-9 microinches of gold which is what we generally require, but I'm looking for additional objective evidence for requiring thicker gold deposits. Thanks in advance. Rick Thompson Sr. SMT Process Engineer SMTEK International, Inc. +1 (805) 532-2800 [log in to unmask] --------------------------------------------------- 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 -----------------------------------------------------