How about depositing a low temperature solder paste on the PWB pads and reflow the BGA at a reduced temperature? Jim Marsico Senior Engineer Production Engineering EDO Electronics Systems Group [log in to unmask] <mailto:[log in to unmask]> 631-595-5879 -----Original Message----- From: Rick Thompson [SMTP:[log in to unmask]] Sent: Thursday, April 24, 2003 12:46 PM To: [log in to unmask] Subject: [TN] 'Unique' BGA Reflow Problem We have a customer who had a custom BGA built with some additional components besides the die under the encapsulant. Unfortunately, these parts were soldered with Sn63Pb37 and the solder reflows and bridges under the encapsulant during reflow. Due to time constraints they would like to find a way to use these while they wait for new parts to be fabbed. We've tried various types of shielding, but the convection systems we have heat the entire part causing the internal reflow. Does anyone know of a focused reflow system that would allow reflowing the eutectic balls of a BGA but not apply enough heat to the top of the component to reflow the other parts? Would one of the focused IR systems (Ersa, PDR) do this? Other possibilities? Thanks in advance. Rick Thompson Sr. SMT Process Engineer SMTEK International, Inc. +1 (805) 532-2800 [log in to unmask] --------------------------------------------------- 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 ----------------------------------------------------- --------------------------------------------------- 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 -----------------------------------------------------