Hello Genny, One option is to have you PCB supplier laminate a prepreg dielectric to the non component side, depending on the design layout it can be pretty inexpensive. If the layout is extremely dense then measures must be taken to ensure epoxy stays off your lands. You could also bond your heat sink at that point in the process, but I think it will interfere with your existing assembly process. Boston Brad --------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8e 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 or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) 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 -----------------------------------------------------