Steve, We are using a Loctite material for underfill of BGAs. It does significantly improve interconnect reliability in thermal cycling and vibration. It is reworkable, and we have proven that reworked BGAs are just as reliable. On the down-side, rework is time consuming and it has to be done very carefully to prevent damage to the PWB. A well controlled process is essential. Tom --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------