Howard, It is certainly possible to electroplate hard gold over immersion gold, obviously provided that the features to be hard gold are bussed in some manner. The remainder of the board would be appropriately masked off using a photoresist that only exposed the features to be plated, just like other selective plating operations. The real key is sufficient stripping of the resist and subsequently removing residual organics from the immersion gold features to allow acceptable wire bonding. Generally a soap cleaner, such as one would find at the start of a pattern plate process, will start this cleaning process. Clean rinsing and drying are important. Follow this with a plasma oxygen burn. Hope this helps...Andy Slade ______________________________ Reply Separator _________________________________ Subject: Re: [TN] Two kinds of surface finish Author: Paul Wilson <[log in to unmask]> at SMTPLink-Hadco Date: 03/03/99 6:18 AM Howard, It might be that the reverse order of application would be acceptable for a wire bond? Is this an "all gold board"? The tab plater would likely sheer the immersion gold off anyway? Paul Wilson R&D Manager / Plant Chemist Circuit Center, Inc. 4738 Gateway Circle Dayton, OH 45440 Phone (937) 435-2131 Fax (937) 435-7698 http://www.circuitcenter.com -----Original Message----- From: Howard Lin [SMTP:[log in to unmask]] Sent: Wednesday, March 03, 1999 12:07 AM To: [log in to unmask] Subject: [TN] Two kinds of surface finish Dear All, I got one inquiry from our customer on two kinds of surface finisf for one board. They need both immersion gold and hard gold plating. Can I dirctly apply hard gold plating over immersion gold on gold finger area? Is there any quality issue that I should concern? I am very appreciated for any input. Regards, Howard Maxedge Electronic Corp. [log in to unmask] ################################################################ TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################ ################################################################ TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################ ################################################################ TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################