Drill a hole in the top, attach a thermocouple to the silicon. You should be ramping at around 3 degrees C per second, and the top profle temperature on that thermocouple should be peaking at 218 Centigrade assuming you are using regular leaded solder. If you are not, you might want to share the alloy and thermal profiles with us along with the bake out times before aseembly, temps etc,. John John Burke Senior Manager - Operations , Optichron [log in to unmask] W: 510 249 5233 M: 408 515 4992 http://www.optichron.com Profile: https://www.linkedin.com/e/fps/2665502/ -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Azman Sent: Wednesday, May 03, 2006 6:47 AM To: [log in to unmask] Subject: [TN] BGA problem Hi TechNet members, I have one issue that I encountered recently whereby my BGA has warped after reflow. Please see attached link below to see how does the warped BGA look like. The BGA type is FPBGA and my reflow profile is OK. Your input and comment is greatly appreciated to help me solve this issue. http://img72.imageshack.us/my.php?image=bgawarp9ot.jpg Regards, --------------------------------------------------- Technet Mail List provided as a 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------