We are using Electroless Nickel/Gold Immersion on both SMT and Mixed Technology Boards. The results have been fantastic on the 100% SMT boards and the only drawback on the Flow-soldered boards is that the pot becomes contaminated with Gold rather quickly. We have stepped up our solder samples and pot purges to overcome the contamination problem. I'm not sure of the exact terminology on your question #1 but I always refer to the Gold used on edge connectors as "Electroless or Electroplated" maybe someone else can help with the terminology. #2.) Our in-house specification calls for 100 microinches of Nickel and 2-6 microinches of Gold. Our PWBs measure 4 microinches of Gold consistently. #3.) Yes. #4.) Our PWB vendor recommends the 2-6 microinch spec. I have seen other company specifications range from 2-4 microinches minimum. Of course another drawback on Immersion Gold is the cost. We were able to justify the increased material cost on the improved yields. We are actively seeking out new PWB finishes,(OSPs, Palladium, etc.) This Months "Printed Circuit Fabrication" magazine covers several PWB finishes. ______________________________ Reply Separator _________________________________ Subject: FAB: Electroless Nickel - Immersion Gold Author: [log in to unmask] at INTERNET Date: 7/12/96 9:25 AM My company is in the process of evaluating the use of Electroless Nickel - Immersion Gold as a finish, for both SMT and mixed technology PWBs. Is this a good plating system to evaluate?? Is there any "conventional wisdom" that we're missing? Secondly, some questions about the gold deposition. 1. Is "electroless gold" the same as "immersion gold?" 2. How thick can we expect the gold to deposit? 3. Is the gold deposition process a self limiting one? 4. How much gold is required to adequately keep the nickel solderable? Any other comments regarding this topic is appreciated. *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * *************************************************************************** *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * ***************************************************************************