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 ---------------------------------------------------------------------------------