Delamination can be attributed to several factors but few a few apply in your case: - Excessive reflow temperature (unlikely in your case) - Excessive laminating temperature (also unlikely in your case) - Defective laminate material (quite possible) - Problem in oxide treatment of innerlayer (also possible, but less likely) - Contamination at the laminate interface (most likely, since your board seems to be isolated case) So the most likely case is external to your facility. Have a nice day, Alain Savard, B.Sc. Chemical Process Analyst CAE Electronics Ltd. e-mail: [log in to unmask] -----Original Message----- From: Stephen R. Gregory [mailto:[log in to unmask]] Sent: February 9, 2000 12:13 PM To: [log in to unmask] Subject: [TN] Delamination Hi ya'll! We just finished building a lot of 48-boards through SMT. Out of that 48 there was one board that we just discovered a big delamination blister on the backside...it's about 1.5" wide and maybe 2.5 - 3" long. There was no rework done on the board, and it was reflowed under the same profile in a Conceptronic HVA-70 that the rest of them were...and they don't exhibit any problems. There no sign of overheating at all around the blister, and the silkscreen is nice and bright white...we just have this big blister. What might cause that? The boards are polyimide. We didn't bake them, and they were real fresh boards date code was 0300. Like I said, it was the only board that had a problem...the rest are fine. TIA -Steve Gregory- ############################################################## 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 Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ############################################################## ############################################################## 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 Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################