Arlene, A couple of the papers in the Proceedings of IPC National Conference " A Summit on PWB Surface Finishes and Solderability" Sept 22-23,1997 will give a bit of the information that you are looking for and a couple of other references . The Proceedings are available from the IPC office. Phil Hinton ################################################################ 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 web site (http://jefry.ipc.org/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ################################################################