Victor- I have three concerns about your situation: 1. Copper migration through the gold. Nickel is used as a barrier to prevent migration. I'm really not up on the theory regarding migration. Possibly someone would care to add some facts about how fast or under what conditions it occurs. 2. If the deposit is used for a contact or connector surface the lack of nickel will result in a short lived deposit. Nickel acts as a hard surface under gold that greatly extends the life of gold used as a contact surface. 3. If the vias will be exposed to the plating solution (especially if they are partially masked) there might be contamination or leakage from the vias that would result in adhesion problems. Hope this helps, Don Vischulis -----Original Message----- From: TechNet [mailto:[log in to unmask]]On Behalf Of Victor Hernandez Sent: Friday, November 01, 2002 7:23 AM To: [log in to unmask] Subject: [TN] Plating Au over Cu Fellow TechNetters, Can you please share your concern with plating hard gold, 25 micro inches, on fingers of a PCB over an area adjacent to PTH's where some unplugged via exhibit SnPb. I guess my main concern is Au/SnPb. Victor G. Hernandez --------------------------------------------------- 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 -----------------------------------------------------