Susan: We have built product similar to this using a process called "Selective First Gold". The Ni/Au feature(keypad, LCD pad, rotary switch etc,)is plated directly onto the electroless Cu. Sometimes these Au features contain vias which require a full build up of plated Cu in the hole. To accomplish this the Au feature is covered with plating resist except in the via area where it is opened up with a pad and overplated with Cu during the primary circuit Cu pattern plate operation. The cross section of the finished hole would be: els Cu 50u", Ni electroplate 200u", Au electroplate 25u", Cu electroplate 1200u". We have not experienced any reliability issues for these products based on this style of construction. Regards Michael Barmuta Staff Engineer Fluke Corp. Everett Wa. 425-356-6076 -----Original Message----- From: [log in to unmask] [mailto:[log in to unmask]] Sent: Monday, July 26, 1999 8:20 AM To: [log in to unmask] Subject: [TN] NI/AU UNDER BETWEEN COPPER I just looked at a product where the manufacturer has managed to overplate nickel/gold with copper. This occurs on the surface conductors and also in holes. I have looked in the design and board documents, but cannot find anything that addresses the reliability of such a condition. I know putting a "meltable" material between layers of copper can wreak havoc, but what about ni/au? Susan Mansilla Robisan Lab ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ############################################################## ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################