There exists a phosphorous problem. Beyond that, it is inadvisable to solder to any nickel surface - that is: No solder termination area should be bare nickel. It should be coated or plated over with a metal, or other surface finish, not allowing its normally very rapid oxidation. More often now, people are talking about the deleterious affects phosphorous, and some other components in the electroless coating process, have on solderability, solder joint acceptance, and long term reliability. There have been many discussions on this forum and in others as the SMTNet. Under electroless gold, phosphorous goes to the solder termination area surface and forms intermetallics in amounts causing the problems mentioned. This is according to some SMD suppliers and others investigating this phenomonon. Earl Moon ################################################################ 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 ################################################################