Hello, Currently we are finding electromigration problem on SOIC16 resistor networks of a particular datecode (9551, pretty old) assembled on a particular card early July. We found from the component supplier that this lot (9551) was produced in a site in China (closed now due to business reasons as claimed by the supplier). Mystically this lot (produced on 9551) ended up in our assembly contractor several months ago. The analysis found Bromide inside the components. The component supplier claimed that there was no way that Bromide could be generated by their process and the problem was caused by the PCB assembly process. However, they were not aware of moisture sensitivity levels when asked (which is surprising I think). Checked with the assembly and found all processes, i.e. reflow, wave and clean, were not abnormal. The assembly uses water soluble paste. The resistor networks in question experiences 4 thermal excursions (top and bottom reflow, selective wave and fountain wave). These components are near a TH connector which is fountain soldered using mini-wave. From the above history, could anyone tell what might be the possible causes? The analyses we are doing are C-SAM looking for cracks and delaminations and moisture content. Appreciate any comments. Thanks, Yuan ############################################################## 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. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ##############################################################