ESCA is a few atom deep surface analysis tool that is useful for detecting trace contamination which can adversely affect adhesion. The contamination sensitivity is somewhat limited at 0.1% but it is a strictly SURFACE analysis as opposed to extraction contamination techniques such as hot liquid extraction ion chromatography. If you don't have ESCA equipment, I am sure there are commercial analytical labs which provide the service - the equipment and data intrepretation is not trivial. For more ppm level detection I have been told SIMS is useful but have not tried it yet. ############################################################## TechNet Mail List 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://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ##############################################################