Evening here, Lisa, your name sounds very scandic. Yes please, send me image, maybe we have same problems, who knows. We use a 560 and smaller, and get sometimes strange joints with electrical opens or even worse. The solderings may work for one year or two or even more, but as we have seen rare intermetallics between balls and PCB land nickel, we think it's advisable to keep an eye on it and learn more. Ingemar Hernefjord Ericsson Microwave Systems -----Original Message----- From: Lisa Anderson [mailto:[log in to unmask]] Sent: den 18 januari 2001 14:06 To: [log in to unmask] Subject: [TN] PGBA Cold solder joints Good morning to all! Question for those with experience in the BGA arena .. lately, we have noticed cold solder joints on the outermost row of balls of a 357 Motorola PBGA package. The problem is not found at any testing stage since the ball and reflowed paste are making sufficient contact; it shows up later after, what is assumed, oxidation forms. At present, we are suspecting 1) coplanarity issues, 2) activation of the flux too early in the reflow soak stage, 3) cupping ("potato chipping") of the device as it is processed through the reflow oven. Has anyone out there experienced this problem? TIF file attached for viewing pleasure. Many thanks in advance for your help, Lisa Anderson Note: if file can not be viewed, send me a note. __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ --------------------------------------------------------------------------------- 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 the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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 1.8d 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 the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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 ---------------------------------------------------------------------------------