To my knowledge it is a myth, that SN62 alloy (with 2% silver) is effective in reducing silver metallization leaching during reflow. Solder has such high solubility in tin and silver/tin intermetallics rapidly disperse throughout the solder joint that a 2% silver content is not likely to any effect in the leaching--actually dissolution-- process of the silver into tin. That is really the reason why the nickel barriers came into widespread use. Werner Engelmaier Engelmaier Associates, Inc. Electronic Packaging, Interconnection and Reliability Consulting 23 Gunther Street Mendham, NJ 07945 USA Phone & Fax: 201-543-2747 E-mail: [log in to unmask] *************************************************************************** * 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. * ***************************************************************************