Hi Tom, You got me utterly confused. I understand you have opens HOWEVER, are the opens related to the underfill?—then they have to be fractured SJs; just because you verified the 'underfill profiles' does not mean that the underfill is doing what you are expecting [see my reliability column in the March 2006 issue of GSMT&P]. are the fractures of the vias?—then it is the PCB and has nothing to do with the underfill. Are you SAC-soldering? Then likely your PCB design is inadequate for the high soldering temperatures [see my White Paper on the proper specification of PCBs for lead-free soldering and my columns in the Sept. 2006 and January 2007 issues of GSMT&P]. Regards, Werner Engelmaier Engelmaier Associates, L.C. Electronic Packaging, Interconnection and Reliability Consulting 7 Jasmine Run Ormond Beach, FL 32174 USA Phone: 386-437-8747, Cell: 386-316-5904 E-mail: [log in to unmask], Website: www.engelmaier.com ************** Start the year off right. Easy ways to stay in shape. http://body.aol.com/fitness/winter-exercise?NCID=aolcmp00300000002489 --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 -----------------------------------------------------